เวชบำบัดวิกฤตพื้นฐาน Fundamental in Critical Care

446 ltnirria1nqndug'ru

7. Secretion fl-fll*tui$on pressure-volume loop o:fioinuru;to.inrldfllrjriu'u o1ofi

n-mrrurnfiruni!fiudoa1uur.rdr,,r dro, lorirrnlariolriflld nnrru:to{ secretion da, onlldrYt

tudroyrslqoon ilru13tfi n?onytaot:ir,:fllfi lou secretion drworo lflu:}grrornrir'lu ventilator
circuit via secretion luvn.rr6uvru'lEta.r{nlufild

aVfi uaat pressure-volume loop duan,sdnaruna\t secretion

8. Alveolar overdistension dng ;1a.1 pressure-volume loop ludr*rfiruro.:nr:vrulc

udr c:ilu'jrrija'lfi pressure '1fldul lilfilfild tidal volume urndub6n 6': pressure filrnrfiu
lldorqrhlfilfio barotraumas ld a-nururto.l pressure-volume loop 'lusirudfi alveolar

overdistension evendlurhn n mnflnr:io plateau pressure ld'lndr6u.: so or.rir nr:rirnr:
flo tidal volume flio inspires pressure fl\t fi1n plateau pressure u-.:i't{a'ln 30 ttl,fT nlfl1{!flc

tidat votume aarvlririrtrln-nunrv:JrnunttrEi udo{qrn anfitflruuln (restrictive lung) riu o;
fio,r'16nruer'rorlunr:rir,:rrru oor lqeriifinrrrrJduuurla.rno.r:J?*rrn: ootiou

tlfr4s uflat pressure-volume loop duant

AnVAtZA,t alveolar overdistension
1u?t'tut,tnaxdutlzzl

Respiratory V'aveform Inrerprerarion $nZunf nfrftr1tg 447

9. orForce inspiration n"nEfuJlan pressure-volume loop !fin,tflnnd1Jnfl.,1 pressure

ludrwrrul,*dr d.'omrfion' d'rto?o.in,.''il'ru1elfiil1d n.]:in'rdo unrrvd'hi:-nurnr,oluor

louraur; metaboric acidosis irrrirnr: illnio,ldrunrutl'birnm:ol tsrunr: ir-r tidat vorume

lfirfiu*u mrn fu tidar votume ud'rLildioro lrtrv'rnr:rfir inspiratory frow rate rrunfiorrurld

tht1.l

1) VCV mode rlilrfrl tiOat votume yrnlrjldnalfiuii:.t peax inspiratory ftow rare
2) PCV mode rJfirfil inspired pressure ldfltrr:nl:"u inspiratory ftow rate ld

Irfi o.ror n inspi ratory fl ow'lu pCV mode durilnr.r lfi ornr:l ot fi:Jr
3) PSV mode rJfltfil pressure support kidlulrn f:l inspiratory flow rate'ld

rfia{eln inspiratory flow 'lu pSV mode dudlnrrrfiornr:lo,:firJ.ru

vrnri'rnr:ufilllounr:r.lfirfir tidar vorume r.riorfrl peat inspiratory frow rate udrlri
ldflo alcfio.rli'rnrrtriuruounri'l (sedative orugsl fiio'hiflryEjounfiurdo (muscte retaxant) fi.I

alruu

ztlii fl uaot pressure-volume toop duan tinuutrfln force inspiration (ainutrtwht) nuuutfiu
force inspiration ifioduluittnm'ralcnaufru ntnait,rtfiu force inseimtion i6nlwh,t

fiTno,tn1tn1u?ctfr't

448 rrujlioinqndugru

'10. Combine restrictive lung disease and obstructive lung disease o11 :Jdnurutloit
pressure-votume toop frilnfi stotfluat'nuilvTtootloadfi compliance 4.r*n:ilooiifi compliance
ofrarsr.rriu rliu coPD dfi nnos drild?u firnriodr compliance l:lddr'lnfir6u.r:Jn6

'hd ru coPD d? rlu AFDS

aptd usw pr*sure-volune toop luStlza coPD ix tiu ARDi fi"qJlianntuJta,t compliance

LnflLnanvna

fl1tlltJf,flfl flow-volume loop

uou (l,tnFuloXw)-vno1tu:|,mr:JenNlonopflotwflu-vorelusmpieratloooryp"duM*.ffdi flo* aqjunu#,: (ttnu Y) trnt volume a{llnu

rr:lni]oldrtiurfiurriunr:tl:Jflotn flow-volume

toop rdorir spirometry lunr:n:recmrnnr aq uti flow-volume loop lun'mot:rlcxllnnlvt

an rjr,: narnrrvruhoonrfluunurrn airurirttrnrnrrvruhtdrlfluttnuau n:.lfitrril{ilrufi

ldrn4o,rtirflfi1u'h:ir,rnnrnr:vruhtd'rrfluunurrn drudr.rtrn't'lunr:firu'lqoontfluunun!

Flow

tthi sz uga't flow-volume toop tiialfrnia,niaantu'lt

Respiratory Sraeeform Interprelation nn^mi $frf,tx! 449

mlxfinilnf,la{ flow-votume toop #nuriou

!1. Bronchospasm vuarufi o:Jnfi1ud't.,:nr:uruhaan Tprus: curve ic'nsru:too

concave

gtti ss uant flow-wlume aop ififnaunat bronchos4sm
2. Fix obstruciion n'nurulta.t tlow-volume loop l:nu'jrfi blunt 10{ "ur. tfo'lurir':

nrrurulerdlrovnr:uru'lcoon

x ifigB uant flow-votume loop tix airway obstruction

3. Intrathoracic bronchial obstruction dnrrunol flow-volume loop eltuirarmuh
oonogndutn ftfinrr blunt so.r curve 'lurir.:nrt ruhaon

450 rmrirriorlnqrduEru

gA ss uan,t flow-volume loop dfr intrabrcnchial obstruction wnuitfimt blunt ltBn curve luil,t

nnnts'hoan

4. Extrathoracic bronchial obstruction onl'ructa.,,: flow-volume looo eJ U'irnl|rnulcd'l
r{rnhrrn i,D]'nr; blunt fla,! curve hdlnn, :vruhrdr

trrt A uaat flow-wlume nop fii extnthoracic bronchial obtruction wruilimt btunt uon

tc u rv e lud1,t n E n t u'l q tfl
5. Auto-PEEP n'nurusto,r flow-volume loop rvr::'lr ftow 'lutirty, ulqoonqohlduqo
fei4ur.i.rIefi"rhnr:ufi,tbnuirirflilr ldnr.imlr nfi'r

Respiratory Whyeform Inrerpreration nn?unf nfrfinJg 4SI

grffi 57 udnn ftow-votume toop fru*atdnwrunan auto-pEEp
6. Volume leakage a-nuguyla.J flow-volume loop cvtrl,ir curve ludl,:nr:ttutlaonco
votume lriduaodfluii

*Etli uto,t flow-votume toop frfi votume takage

np

n'llrJirfiutrY!n't?ulnr{n respiratory waveform finrrrirrijulunr:n$nffjxflyr'ifilni0{
tirunralelun'r:guouevrflr:virftJ'rulfi:inasn-u adr.irfrntr {dnun{rhudtdraio.nj,rurrulodo.r

bjn: lau'lunr:n:rcdr.:n'ruuavd.'rrnndnuru;vn,,rndf nror{ilrr nlr.r rirtclu 6o,,r nr: *r n ru n

respiratory waveform rvsird qcdrutl4nr:ouoprudldrnio.rrirunrulcldilr;lwridrriufl,:j.:u
otir.rfirh;6lyinu

452 r'rtJTrintnqrfrgru

lonfi?fi1it6{
r. rprdlnnd fifichfirnr. craphlc analy!*r in m€chamnical wntil*ion..1u rprfirnrd rlfi{arrrfi: Mschanical

vontltation and l€5ltralory cats : prindple and FEc1ic6. rloufhrnrf,urt nTlnlt: 2546t507'44.
2. Tobln MJ. Prinipl€3 8nd gaclicE of m€chanical r'fftllstlon' 2. 6d. Mccraw Hill' 2006.

H63- DR, lGcmar€k RM. Es8€ntal of Macl|8nbal wntilstlon. 2'' €d. Mccraw Hill' 2{D0.
4. Susan LB, Rohf DH. Det€minanb of Patl€nt-Ventilator Int€r8ction: Bedsldo waveform analysis, In: Martln JT, €d.

Princlpt€s and Prac'the ol Intorciw Car€ Monitoring. McGraw Hill, 1997:655-66

25

Noninvasive Positive Pressure Ventilation

nniuux n0tyurila$t

{rJrufifinrr;nr:nrfl'lcdrJr ar (respiratory faiture) finfiaddfunr:int'rlnunr:'laiviodT u
nru"[t lendotracheat tube) un:]ldrnia.,rrjrumru'lo {mechanicat ventitator atir,r'[:firnunr:'ldvio

drufirfl'lo unJldrnia.rtiranru'lcfuriotrtrfinnrr:ur:ndourir,llrrnuru rtiu nr:lro rfrraw'r,:

t6ufi1alq6i?uu1.l (upper airway trauma) logon[f,!e']nnr:ifila{o,rtjrutrttq (ventilator associated

pneumonia) Tr:toXndnrnr (sinusitis) rflufi! uoncrndnr:'ldyiodrflHru'h un:tdrnio,rtjrunruh

riu ri, tfifirtrtrdologluloigun;1:,:r'ruurnurunir nB rfir nnrnr:rdtnio{ri1flyru'tq (weaning
from mechanicat ventitator) dr#rr{u6rilnrrsrrr:n$aurirol'' 'lutjr{:;flcrrnrynrufldr.irurr

ldfinr:rir noninvasive positive pressure ventitation 1rueev1 ltldlu{'rlrudfinrrcnrrfl1u'[rr']u

rrndu drtriarrr:nndnrfiurn'r:'lairiorirufirflle (endorracheat intubation) rroyfla.JrTuntc

nrruu:ndoufr rfi oqrn nr:tdviatir ufi ru'lc un ; nr:ld lniartir uyr ule n6Jd

llnarrildc;ldljrroua uurrlr. unr:'ld Nppv irlyrltlfiffi il',re;ldn6imfirnr:rdan{rJ'ru
nr:rdanq n:niei'rr1 nr:oY,: rniatdrafiru'lc nr:6onr lfir::'l-run;nrr:u :ndaufirfioernnrr'ld

NPPV

n1x[68nf,il?u (Patient selection)

znr:rfi ond:-h urtufi :J:: rfi udda,rnerfirfu :ynr:fi a

1. . fmafia?anllyltaAtal"jxuLLalu

ullz. dnuru;n ot fl,rJr ujr ryrur : Rn rilnr:ldrn4o.:tiruyr utl trtppv yio'lri

454 rrniliainqnfruSrl

I:nrionlr#{rtzufiu

finr:finurrir,.r1 rrnrrulunrrld Nppv 'lunr:int'rnrlcnrtvrutqd tflnrfi.:ldnrnd rflufr
rirnoh d.:q:n:insiol:ld

1. Ghronic obstructive pulmonary disease (GOPD)

NPPV ld0ndlultd'h COPD fifi acute exacerbation unfiqo Brochard trnln r

ldrhnr:6nurru'irnr:td pr"ssure support ventilation r.jrulronirnrn (mask) d'lu'l:nnnn1l
lsiviorjrunru'lc :vuc nnr'lunrltdrn{o{'rirunruto rn;:;flvtrnrfida',ra$tulofigotirdriudrdq"
u"nmnd Brochard nru:ldlirnr:finurtu{ilxu coPD fifi hypercapnic respiratory failure lnu
nr:l:Jiu! rfiurnr:inrrlaruldraio.:iiruvru'(l Nppv un;nt:fnuurn:3lu (standard therapy)

vrrlirfil.rr:nnnnr:'ldrioriruflrutemniaunv 74 tfluiouav 26 antuv!?n1nr:og1:orurlra
?rn 35 iuriu 17 x'u nno'nr1nluqrntouos 3t tilutauat g ttnvnndq:rnrltfis:Jaod'ntwlqrn

iouac 48 rfluiounc to fi.:firitrdrn''ryrr,oof,6n Plant uatnruvldntrnr:finu'r'iu{rhu coPD fifi
acute exacerlcation 'tufirha.fruru eeo:ru d'Ifio'irlflunr:finuultt randomized dfiriruru

{rhulrndqo lourirnr:flnur r iti! rfi ulnr:ld NPPV ril5uu!fi uufiurirnr:fnrrmn:5ru mlir

o'n:rnrr'ldviarirunru'lenqn{trniounY 27 tflu{ounY 15 (p=0.02) tta:aoo-nltsl'luetniounc 20

rfluSoirn; i 0 (p=0,0s) uanerndr:r'ir'lun4#id rueev "iru'runi,,:ta.rnrtvrah rra;nrutflu
n:nturdandt*uori, .rrror5rrfiouliuurfi rununojldlrildlfi NPP\,P

uanrrndu'rfinr:6nur'lu{r-hu coPD dfin'rx; hypercapnic respiratory taiture fifi
coma o'rn CO, narcosis TounJiu:.rufiur:fl:-irli Gl"..got coma score 1GCS1 lrnn'lr 8 ttn;

rioun'ir e vuir'lunsjlto'l ccs fioun'fi I ::d'lraatomuj6lnq-rdt'uatjr'lforouriialt ttppvb
rudr t :irL,l (odd ratio= 2.32 (1,53-3.53)) rrdorjr':1:fiqrilnr:rir rueev ilr'ldlufiilrufi ccs

rioun'jr e riuda.:'lddruartr:srierct-,'rrda,:crnfiTonrniifilrulvrfinnr:drdn (aspiration) 1d6

ruurrruJfrffitru:d ulnir}ilfi rueev lu{lru coPD fifi acute exacerbation dfi

nrr:nrtr,rrulo':rsrfl uo"uo"lu:n firLifi{ofiu (contraindication} tra.rn'r:ld t'tppy'

2. Asthma
nr:fl nur nr:'ltfiilxu NPPV'lufi rhu asthma fi doudruiou fi nrff nuldournt 6etro-

spective study)'lu{rhu asthma r:Jtu!rfiuunrdd NPPV nilnr:inururn:Srulufrrhtrdruru 3s
:ru,rr.rirnr:uan l:Jdulffrt 1g"" exchange) uo:{rgqrru6r,r (vital signs) lunrim'td t'tppv 6t'u

adrrt'nreuu ndnr:ifnnrur.rnt:dinurulr'irnr:ld ueev tu{ilru astnma lrildrJ::lamitotoun

o*rdri.rLjfiniuu:rir'lunr:1fi Nppv 'lu{rl'ru astnma jrld:J:funir'nrourialri
rfioocrnnrrts NPPV lu{rJrtr asthma riuclfioofinrrtflrr:itorir',:6 lu:T:{rJra asthma firfi

ornr:udnr r;ueja,,,rodr,,r:rnr5r d,rdr'ldviadrufiruhdrestfinerntfiuriilfirhuld

Noninvasile Posirive Pressure Ventilation nn?uni nfrfit1t1 455

3. Upper airway obstruction

lifrnr:rir ruPev lrldtu{r-hudinr:oqn-uzo,t 1,rl6ufiu'lad1u:.tufirfioorn gtotric

edema qrnnr:'tsiriatirayrul,s odril:frnr:.rnr:ld rueev'lu{rhlndrdfio,,rGonuruo;rflr:y.l-r
odro6 drfi:Jrrfiornrludn.tornnr:onn"uramr,:l6urru'lodrulufrorldviorirflHruhrtiufi drunr:

rjr trtppv utff1u upper airway obstruction drfiatrncrrrstdu {tignt. fixed upper airway

obstruction) nr:'lrtnr:inurTeui66uidarrr:nufi}rnr:qqff-unfl{T1\trfiuyro'lold

4, Cardiogenic pulmonary edema
finrrfinrrnr:'lfi NPPV ot'1u? 1nlufirhu cardiogenic putmonary eoema los'ld

continuous positive airway pressure (CPAP) niu nr:finutto,l Rasanen rrayn c l6lirnr:
fintrlounr:ld cpAp '10 rr.rir tu{ltru cardiogenic putmonary edema r:J?tltlrfitltlfi':lnr:inur
rrn:t'tunu'irnnran r:Jduufrrrrtaca-n:rn1:firu'loono.loti.rcfiriurfrn'cg'o ntfinurto,l Bemsten
nnynnr;ninr:finrr'luriruorrdurrir.r urirhn{ffi'l.fi cpAp finr?rranul6tuffrrddu dor:rnr:

vrulqnon.r aonr:tdyiorjrrurutc un;nn:yEJl lrarnr:a{1u1a6g"

lunl.rrnqrfi Nppv lirc:fi{ofinil CpAp 'ludrJrtr cardiogenic putmonary edema

ldamrnOrlr:nnontyit,lturatnt:rrrLh (wo* ot breathing) dtlr:nnnotnt:rtrfiau rrfftd.trJt?n
aa:cq'':J?,o,: paco, ldn'n'j1 fie'rnu'jrnr:'ld ttppv c:fi{o6n.irnr:lfr cene lu{rhu cardiogenic

pulmonary eoema yialri finr:flnrruu randomized uliurfialnr:ld Nppv un! cpAp 1il
fi tu cardiogenic pulmonary edema ulirlu{ilrufi1d Nppv fin'l?aon\:so,:dn:rnr:firs'lc :;o"r
co, unvornr:rrdourSrn'hn{ldid cpnp uriadr,rl:finrdunsjrfitd Nppv riuyrudsrtrn.rlfio

nd, lrdori'rlocrr (acute myocardial infarction) dlnir'" lronr:dnurlrivru'jrfinruunnri drjlt
firiudrn"ry'lunr:lfiondrilrdor,rrlqnru'lunailfrld ruppv yia cpAp'3 lunr:dnuruu.r meta-anatysis

lrhrrirfinruumndr,:tunr:lfi cpnp yia Nppvtunr:fnurd tt cardiogenic putmonary edemaa

'lumr.rrJS^l?rdavufirhu cardiogenic putmonary edema firl'o.rnr:1ri1uu:,:nr:r6on1d

cPAP riou firu"rnrfiornr:unfiou iotysr'rro,J Fbco,Liflaa.:6,:rlduur*fi t'tppv odrtl:finrllfir

fi acute coronary syndrome illn"l cardiogenic putmonary eoema fia'jrrflu{ofiu'lunr:1fi

nppv nia cPAp d0,r'ldiad?unrfl1o?iufirdononr:dr,lrurolnr:rruh lwork of breathing)

5, Pneumonia

fi nr:dnurulu randomized nl'jrnr:ld rveev lu{ilrurJondnrcl aur.:nonrnr:'lei

riarirflvru'locrnSoun: 50 riuSoun: 23 (p=0.03) nnrrnriio{lulofigc'tn 6 itrrflu 1.8 1i1t (p=0.04)
ruo:flrlr:naoa-n:rnrutun{r4'rhu copo fifirlano-nlnldrlfiru'' finr:finurdrirtufi:-huilsetd'nrou
dlrilfirflu copD ixrJd'lu viuirn{1dl.fi Nppv in1:udnr duuflrsdn.ir ::d'uooniroudn.ir urd
lufi {niaua: oo fr do.,rndrm'ldriotirurrlhtrri'u

456 rrtrirrioinqmfiugru

nrorJflrifiu-,ililfir{ruu;rjrtrl'l'fi neev'lu{rlrerr.looo'nrnlfi'lrilfirflu coPD odrel:fin'u
fi rirufi riuiloo d'n rarlduriu coPD nlr'ld NPPV fi esldrhvTusf

6. Acute respiratory distress syndrome (ARDS)
finr:finurnrr'ld runev tu{rJrtr nRDS" orjr.l'l:finurirr'lrjfinrrdnurtetfrf,rrr:nron

ld'irnr:td Nppv d{fidnllnrsaoaoniolriluvrrlrJ$rihfirfio.rnr:ld rueev nr:tdlu{:-l'lu ARDS

dornr:1ri:uru:rryirrfu uacfio{finr:fiqntrflr::r-,,:otirr6 fir{:Jrufiornr:utda{do':ldvioriruvra'le

Ytull

7, lmmunocompromised Patient
tu{rJrufifi:rrr,lqfi{r.rniulnvldotdurilnrr;truhrrs nr:'ldvio:iruvruhorcf{fifi

nr:6ordoturlon ntilduld finr:flncrlrrlu randomized tu{rJrudfi:;uu4fi{lriu:lnn'iaodrHriu
n'prnralolu d'rdruln{rflu{:JrulvtS,lvrolnfinirur (hematologic malignancy) nuirlu{il':u

n{ffilfi teev nrr:r:nnotnr:tdviotiruv, uhorntoun; 76 tttfiotounc 46 (p=0 03) nqnl?:

urnndautto:o'n:rnruttnSoun: e0 tfifioiouav 50 (p=0.02)18 riioulSu:Jtfiallnir.rnr:ldviarieu
rr ule:Jn fi vru'itfi a"n:t nt u d'r' n

nmJfr fh nr*fi ru e rv lu{rJrufi fr : :u4fi {lriuundo,ti': ltdunm:ur uttrluriou{r,!
rirouh rdomrnsrrtnonnr:rfiqntl: urn:ndauetnnt:fin rdodrfinernnr:ldvioriruttrulclfi u,ti

odr.:1:finrrnT :flo.rniufi'lfirfionrrvrrr:ndauvrrnJaqlu{rlrafifi:;u14fi{rln"uunnda'lcsrflunr:

:!flu1Td9- n'l'],:J1n -

8. Trauma
finr:finurtoo Beltrame un:nru;1u{rl'luql5rrqfrfi flail chest frfi acute lung injury

irnlriluu:r rr:lirnr:td ttppv otrrrnrirlfinr:ttan t:Jfiuunrtddufitfoun: zz'o odr''rkfinrrfl:.Jru
n{1fi gnlrilnfi (burn) nolJd o.ttianr:'ld t tppv 1rj6

luvrrurlfi:ihrT'rlilfin"ruuvrjr}it'fi necv tln{rrf,:Jruq:j6rrErdo.:rrnti.:lrifinr:finurd

ruoo,:'ir NpPv ldrj:;Trrf ufi u.':uo

g. Restrictive lung disease
finr:finr*rflouvn-o (retrospective study) fiuoo,:'irnr:td ttppv !{l::Tutrilur{rhcl

kyphoscoliosis" ua;T:R neurorrsculal' 'lunr:iinnno{ Bach ttovnruvvtl'jln-ntd NPPV lu

{ xu restrictive lung disease fi fi acute exacerbation 6l't:J'tl0aqd'ntlnr:uou'luf:{ ururn.ld

0U1\:tJUUfllnrlJ*

tdo.:lrnl:nn{u restrictive lung'lul;uvfiru rinfinr:lurun':touJoo (lung compliance)
nna{ uacoon€tculurdonnontodr.lrln (severe hypoxemia) nTttfi ruppv tuflrhanq'd5'r
hiriauldil:vTusdM{:fn

Noninvasiye Po.sitir€ Pre.ssure \.'entilation nniunf nfrfi$S 457

10. Do not intubate patient

{r-hufilil0uuortunrrtdvioli?rrfl1u'le nio{rrufiurvr6a{a?1ilrfiuud?.j{rjn1:i6ivio
rirHfirflle nr:'ld nppv c:rflu6nrr.tr rfionvfi'rlunr:tira mfio{:Jrun{rdfifinr.llnralerru finr:

frnsrnr:'[d ueev lu{rrrudlriuailldriatiruvru'lqo:ruru r 3'r :'rr vrr.jro'n:rnr::aoiinm'oaan

crnl:' ruurnfiolfluSoEjnv zz tu{r.Lrurhviu:Jon (purmonary edema) udyiaufl; sz lu{rhu
copD 'lurru;ir'o"n:rnr::aoiinfiaun'jriofln: zs lunq'rfir-rrarJood'nrd:.r lpneumonia) rior; r5.r

(malignancy)'?4

11. Postoperative patient

finr:6nur1u{ilrurn"loirri'oiififi paco, 1nni1 50 rr . tayl r5o pao, riatnir oo
rr.rj:ov riofinr:firuledourr:s'irnrrr:ntd ntppv 'ld" finrrfinrr u:.r.r randomized tufirhu

fivrhnr:njrr,t"'n lung resection vll'fiorm:naodor:rnT :ogtulofig oori'nrrnr:'l6iviarirslrute uo:
on o'n:1n1fl a dr.,tflriu drdry*

nr.rrJ$l"no'rrr:nrir Nppv rJ1'ldlundrrftJrufifinrrlnr:r.rrstl.rrafifr.iro-e'ld lr'ifirrJ

tfi rueev tufl:-trufildilnr:rirq-ornoro1fi1r nt:r 11:oryr: yiorr,rr6uyrr'ledruilu

12. Facilitation of extubation and weaning

ttppv nnrj'rrlflu{rhlfrfiiftyurnr:yrttqrirlrnnrsnd.lnr:nasryiadrtyrulo io
ldlu nr:vd.ltn6ortiruvrulo finrrfinurtu{rJra copD e'1u.ru so :rflfildviori.rufirutlrrnnir
+a drTil-r unvlilcr r:onoerviotjrflvruiq6il5e tourir{rJrun{rdlrnaflyiodruyrfl'lq ua:lfi lrppv
oioriufi rujrtunq'rn-td ruppv orm:nvrLnnr:tdraia,rd.:uvrulqldiaun: eo rliur rfitrrLni:.rnrlr

lilllfitfi r.rppv 6ofia'n:rdrrtciounv 66 dr:rr:nnnr'ruruiulunrrog'lulo6g unr,fiuo-rr',nrr

:oofiisrfi 60 riurrnn.ir"

ilnr:finurul:.t randomized Tour:l5uu rfiuln{l{rlrudnooyiorjruyrul,cfirli6at:rnr
lla:nai fi:-hafinaoviotjruvrulc r5r (earty exrubation) s',rld r'tppv oion"ufi vrl.jrnajr{ilrunol.fi
t'tppv fir:u; rrnrtunr:ldloSo.rdrwruterru! invasive rioun'ir urn'::s:lrnrfrtdrn?o,:rirurrute
n'.rvlourun'jrtunalvr'lfi ruppv'"

'lufiriruioanviotirurrrlo udr lanroiido,ilsivioririlrru"htilri6nrfluiouac s-zo tu

planned extubation rrn:iaan:40-50 unptanned extubation rfiondnrfiurnr:fi6a.:ldviotiruyruler'l

r-.rld'finr:rjr rurev miflu{ilrurndrd Keenan ua;nuv ldrirnr:dnr*rtufiriruii rfldrn:yu:r

nrulcv?afix'leiivrhnr:oanviatiruvrr.r'loufirfinr:nruted rfin? (respiratory fairure) n1fllu 48 dxT .l

Iour!luurfiur:lv'jrm{ldtd rueev uavnr:inuurn:gru vrujrnrrfifiortdriotirunrulotrrjtunq'r
t'tppv ua:noildldiunr:inurmn:grukjunnn'r.,:riu (p=0.0g),'

13. Sleep apnea

rflunt;nfjrfr'ldfr-rn.r:6nurtuqcrurnl rornr:'lfi Nppv lrxmmo{ steep apnea fi

458 remilioinqnfrunu

lfilr;lurdqrnnrrld NppV fig central sleep apnea t[a! obstructive sleep apnea 6['llJ'l:0no

nlrix,i'lut?n1fl41{i1-t (daytime hypersomnolence) 11flcn1:flna{'?,anoonA[4u'[ut'Ifl1n41,]6u

(noctumal desaturation) f,1tJ15narlfl11;ttYllndouei, ,,l'i ld 6orflunr:insrillnr31utu{il'lun4:l

u-

finrrifnuua.r Esterban uaiarutlufl a.a.2oo4 6{nrrnalolnrr'l$ NPPV lunrr:nr:

r'ru'hfirJr fl?n1uxailnr:oooriodrurrflle rri'10i61'lnr:'tdviorjruvrutedrlu{rJrunep coPD Rq
n,r 'lurru:d{il?un4rududhl:; coPD fidmr. n'rugtdu lnunv.lRo':n{rfio"ntrnr:'ldviorirarru'lq

drrirrYu6oioua; 48 aT nnl?6inu1dil1eY6t,rfln'lfiflT rld NPPV hrd!'lsfllrjrflu copo fiottdotrl
:r -fl:ci{ rnrsu'Inflf,1il NPPV frr.J:;lutritu{:-l'lu coPD fifi acute exacerbation rrndqo

dnunxmr firilr ud tnmveuiu nr:'ld N P Pv
t. arnr:iirilfi.:nr':r,nu'lodr tnnr (respiratory failure) ldttri nr: ru'lcti? (tachypnea)

nrlrrutqlnfl'ldnfiurriodu (accessory musclel :irulunr:vrEJh n1:firulelnutdnfiurdofia.:

(abdominal paradox)

z. nr:r:Jfi uuu!nonr,onsrici:irardrdrlfi niunr:nrutedilrtnr
1) Acute on top chronic rqspiratory failure ttiu COPD dfi acute exacerbation

2) Acute hypoxemic respiratory failure niu cardiogenic pulmonary edema
3) Chronic respiratory failure niu obstructive sleep apnea (OSA)
4) Facilitate weaning from mechanical ventilator

s. flrJr a fi a.:fi n'nuru; n".:d

r1 {ilrufio.rfri'r 'lfinl:.rirlfia6 rdo.':rrnnr:'ld ruppv dattdvrirn"rn (mask) d',t

{ilrudo,,rnra'ldudunr {rlruur.:'iruorlna'':ld
z) :vu:.rnr:lun tiiuuloft ndo,rilnfi

s1 ror.ru:lrirrn drfi fi ooorm:nloosnld

+) nr:.trr nfl o,:niunrr drnnlfi

+. f,ariutunrrtd Nppv

t1 {:lrufirqonruh

2) {il?udlri'lfi n?rrierlfi o

3) {rJeufi na'rfi unr (claustrophobia)
4l {rJr udirurnr?anrun oG'lu {:Jru coPD fi fi Paco, d''r do,ildfi x antr:l:vfior:vit

ffli"rrtlrr1u?d0fnir?vuuRrnil\lvrdrbnnl?riEuudgllvai.f?isiliillr0i:qJn(cfai rdnijougenn'rircilop'u'ulm1aofnifaidrry fl'r'terdufiodonr;dlri

edema) dtlfi'l acute

coronary synorome

fi:-l'lafi fi uT rrunrnuirrnrhnrir

Noninvasire Posirive Pressure \-entilarion @niunf ]frfinJT 459

z1 firJrufi fi r:Jnrirfi erUn6!rn (faciat def ormity)

8) {rJrtrrn"e r.lrn'oflr.lr6unruledru! flaoo'ltr,n yion:;wrr;otn: rda{erndrtfi

ruHarirnio uun'ld

tnr:rofi unar': a-nrru;fi rJrafr n'l:'ldunyhjnr:ld r,t ppv,'

Appropriate diagnosis with potential reversibility
Establish need for ventilatory assistance
Moderate to severe respiratory distress
Tachypnea
Accessory muscle use or abdominal paradox
Blood gas derangement
pH <7.35. PaCO, > 45 mmHg. or

PaOlFiq <200
Exclude patients with contraindications to NPPV

Respiratory arrest
Medically unstable

Unable lo protect airway

Uncooperative or agitated

Unable to lit mask
Fecent upper airway or gastrointestinal surgery

n'l:r6an Nppv ffi cailn:niiilddrrui'u t'tppv

n1:r6sn NPPV
NpFry !iun1fli?gyrulqlouldnmiln'umnlouLifioildilflrirtryruhlpruiln6rnio,rrhmrah

inrrTrnnirflu NPPV16fi z l:;lny6a rnia..:tiru?rrutefildtulodu lcriticat care ventitator) r!fl!

lnda.:drir ru'hu u bilevet (BipAp) hjfirnio{ti?irrr l J:vrn lniidalrl:niulu [sio: :ymyl

fida6{orfi uri.ruonrlunr:r,:fi z'lun1r;l6uuvrau

nttriisn mask

::mlili'rnrn (mask) fi'lflu ruppv firnru 2uridldriuTnl urninfllufi ry[n 6a xfi.l

nlnn:oUe n (nasal mask) rrn;fifiln1nnto]ltiY,tl$n UnV rn (oronasal mask)

1. urjrnrnn:oroun (nasat mask) yrirnrnfi6nr:fidru:o,riulu'btfir (inner tip) ufio

iorriu'lrilfilfin unrannri:.l rrirnrnfr6axt't't{rruldiyrn- nr',rdruttrro,nun airulularrfirnrrl

R{rfiu z/g to':f,ucrn drunjr'rtrroduuiril 'rnuu da.:ryr"rnrrrrlufirnrnltgnenutd.tu medial

usrtrifinri, (air teak) Idrir,,r rn:r:rf u1il.lrildiir:1rifial:"rrau do6ro.:nrjrnr:n:auornfio

460 rrtrirfinlnqorduSru

znrr,$ r:l5r:,Jrfiur{oddordutlo{ tqiaadruvrutadld"tula€grra:rnio,tdrautu'htttttl bilevel@

Inspiratory pressure ++

Leak tolerant +

Different modes

Alarms +
l\4onitoring capabiliiy +

Battery

Oxygen blender ++

fry""= f

' += present +i = better; - = absent
t Newer bilevel devices incoporate graphic monitors, oxygen blenders, and sophisticated alarms for use in the

acute settino.

{:-hunrlr:n4nlfi narfi:J:;vttorrr:lridottormirnrnoon drudarfilfiofir{r.hahjaur:ntpfin
ldofivecdrlfibjld tidal volume iifio.rnr: frtarqrrfi1trl6'loulfif,rsioart (chin strap)

z. ntirnrnn:aun'.:e {nun: rn (oronasal mast<) udrnrnfidfiolfi3rudfi ila'lrTunr:no
rir nr:rrrvritnrntiod'Ioflil'x'hlrr,rttjur6urfiutlrirn'rnfin:ouo4n dadto'tndrnrnn:olllnttn:
:JrnFs ar:lrntdldtu{rJruddrrJrnrdovruh finr:irnatnrtiaufiqo dru{orfiu6odaororufir
nrntfindaon lrarild::vnua'ur: trn:{rlrulrjeur:n1old urirnrnil:;mu6u1 niu urirnrnd

nr:rod g uJiu!rfi uufiirnrnn:our4nuo:rrirnrndn:oun%tJrnnn;04n"

Claustrophobia + ++
Febreathing + +
Lowers CO, +
Permits expectoration' #
Permits speechs # +
Permits eatingd
Functions if nose obstructed +

+ = possibl€: r-+ = more likely: r-i-+ = most likely; - = not possible.

t ExDectoration is possible but requires the assistanc€ of a respiratory therapist with the oronasal mask

5 Speech js possible but may vary depending on the degree oI respiratory failure.
b Eatino necessiktes oronasal mask femoval and may be contraindicated in patients v'/ith se\,,ere respiratory tailure.

Noflinvasive Positive Pressure \-entilarion nniuni frfrfig 467

tgli uaat masx rfradt,t1

i za uan,tnitntndazoyyfunrttuaz7tur hetme1

v-nrouftfifil (fult face mask) r?arrrirnrnfinroun".rfi:u: (hetmet) ld'lufirlrE frl a'auirilfiofiia

fi:Jqnrnlii (air leak) rrn viorioyuorlrn (mouthpieces) fi:l:;lorrilu{rJrudtrjorrr:nldnrir

nrn fiorfifiijn:|nrdorieuoonr::'rlo,:nl orcldfiiloln'j'lrdrufirfinlirflr,:qtn riaRooluc n

of(nasal pi llows) tfl unrt rd gnlo,:yril n'tnnr oua { n il',r crl r:n n a rrru an fi

flri6

n1liofi'rur 1n1nrflufr.riidrd'rg rjaun{,,rrujrfinr:fqii udrrfiulJ {irarqria'lfirfio uflann
rftr lpressure sorel ldTourour:uirrruduo4n nrirnrnddnr:io'lfiuuluoilrilriuourfiul u:rnn
or nyrirn'rn6a,: lyirriunatvrrr fi rudrtr llo zdrurlr

Ventilator tubing unrmiarrt'rne'uCu (humidifier system)

ventilator tubing fl0't NPPV Tyno druviarirnrslfiu,J rdu16ur riordrrYrrrirn'rntf nrn"r.r1

rniomiruvrulofiaanu! d1rfx Nppv laulo lyoyti'1,,1il16lflilJrnfirfiafinrri'nro,rntr6nrias

462 rrtrirrininqndug,u
6,:fitiarruruffrso{drtoru tubing circuit vtadnrirnrn NPPV a?rilttLxrirnrudu rfio'llrn
nlff'ru'terolfllsfiufi,':curfiulildr'hirfinnrrrvnrut6otto,rldo:LJur4n rlrn rrnsvnonorl6 ttotd

unheated humidi{ier fr rflunllrfi u'!l',lottdr

nr:d.ruaio.niesr4lute N PPv

Modes

riuaqjrYlmiartard'rrdar:;n'jr,r{rJruun: rndo,rrirauruh ls,untTlilrrfir moae fifiuildfi

4 llulj
1. Bilevel positive airway pressure (BIPAP) fiotfro inspiratory positive airway pressure

(IPAP) ufls expiratory positive airway pressure (EPAP) d.Jfiri1 IPAP !!d: EPAP lriuhfiu lnu

{:Jr uri'rnuno"or:rnrrvru'h lo.l

2. Continuous positive airway pressure (CPAP) d,r tpnp not epnp wirriu lau{rJru
drvuo o'n :r nr:rr ulc la,l

3. spontaneous time mode rflu eipnp via cpnp dfinr:fria'm:rnr:uruh (respiratory

rate) Ud?s

4. Volume controlted ventilation flia Pressure controlled ventilation 'lutn4o{tirurrfl'tq
il,filuloig d,,rnn-nnrr'lunrrdlrn5o.,rrra'tm: miiourir{rtradlsiriarirun, ule eclritondtfi'flu

{

lJvr611U1-l

rdounvrfr6onrndoujruvrulc ua:urirnrnfitnrrvalnir{ilrlrrdr'hi{n{r-lruuauogitu

rirfr:x;g,: ls a,:or rilnrndot Nppv tiilfi.r IPAP :hc 1ru o-a til.fr ttn; EPAP rl::tru z-a

mr.rir n':ouvfirnrnua;tderulna.rr4roiurudr*rdu

glii e uaolln:n{ath{ttunuzfi?i neev

Noninvasive Positi\€ Pres$ure Venrilation on-zunf afrfimg 463

n11#.t inspiratory positive airway pressure (tpAp)

leurtdilrdil#,i:J:crJ'r 6-8 t*,.t|dsu homrr tidat votume ddriruldToutli! rpnp du

n:'oo, 2-3 tr.rh drulrqiudrfnLifiornr:rfiu rs lu.rir irrruror rpnp drrndurvduniuf

firLrlirrrunldoonlrnrn*o':fiurldu dlntrtfifinli:;orurfio,,r,no.,:riiauro.rrr.:16loln :Jrn ttacoo
(mucosat irritationl lrinr:#.rrfiu eo-zs tu.utr rdo{qrnfrtfix;nnrunr,:la.rvflon0ly1i (lower
esophageat sphincter) rfl q n1ltfi rfi onr:al'rdnld

*rrrir"nfialuoltfifi nr:i.nalarnraldrir.,:'lu,ruvfi':Jiu tpAp nr:fi norunr:ld rpnp Tns

nq'ln tidal volume, respiratory rate, minute ventilation, arterial blood gas pH !!ny paCO,

ntt#t exspiratory positive airway pressure lEpAp)
Iq ufltrlil il"neYol :crru z -4 sl,utr riori u n riu'tu{ilr u cardiogenic pulmonary edema E.tQ
ldsir epnp fi4.lnirfldTnu:.nfu epnp duni,lny z-s srJ.fr fionlic oxygen saturation !!oc

n"nrruvtalnr:yru'lo'irfioddndtldodu (accessory musctel rirulunr:rralwSaLi lun:nid
fio,:nr:rfir epnp arrfinorir'tri:co-tlro,i pressure support nnot rir'lfi tidar vorume LLfls minute
ventitation non'r airarntr{ paco, R-{ 6rdauJil tpnp nr^ilorilriudru

Pressure

Time (sec)

I **,nnnE uaw pressure time tazinu'lqTnu'li eipee

nrr"to rio,

nr:n".: nq r*lrirwsrBonrntal{fta lrrurfiLtfnfia.lnr: Fio, iior r:ninsr::auro,J
eaq fi oo *ru.r1:ovr nio oxygen saturation dSouny so donr:rliu riq rfud.:utnrlo;rir1fi1u

rnia.:dr uilr uhdtf'tulof u

nrmifit run{,rlunmiruurak (back up rospiratory rate)

nv,,:'lu spontaneous time mode Aruln{o:rastliii tz-ts n:;.ruisurfi

ntoo pr"""rr" rise time (pRT)

pressure rise time 1en1 llrufi,:nr,:n"rr;u: nnrtunr:duro{ tpnp culd,ryfr-udfia.:nr.r
rrnrdors.: rnriouc:dua4n-u rro* d{rtrufiarnr:'lurirryra'hrir fir{rJrudo.:nr: flow drir nr:#r

464 retrirUalnqnduSrl

pressure rise time du rrdfir{rhudonn1't flow d'l n?lns,.t pressure rise time u'l? 'lnuilnfiol:dr

oressure rise time lld o.g-o.s lurfi

nrt#rr percentage of inspiratory time (% Ftime)

dun-u'irda.:n,zrirfiun l:E rvirl: dirdolnrrnso l:E girrir t:z 1fiftir l+ime $% d.r

nlrufi,cldi'r E-rime 66zo drdoanr:fo t:E ri, rYu 1:3'hifr,rir Ftime 25% d.onlrldildrh e-time

zs% rfludu

nrfinn'uuf, cnrtlfl rtcar rdolf N PPv
t. rnioori'lunru'lc NPPV fi monitor un:::uuntttfiou (alarming system) fiounir

rnio,njruilrulcr!ilua::rqr drriuunvrti6':dorfinnrumvrilr:vftodrltndfiolouqn"nuruvnrrrruh

clurunillunr:firuh tioat votume ttnv minute ventilation nrrudulnfin ivrc: finnrladu}iflr
fi'rh (eXg monitoring) SaO, n:?eirnflsfflrslurfionrrnl (arterial blood gas) lrflvn1 d1ui.ta

Yll?it8n (chest X-ray)

z. rdoriuduld NePV 1 l*riuln fior1finor{ilrutunr:{utaurYl rueev dou ft{:.1ru

urrnuwfilndno-o nn''r'lunr.ln, ulltud unu n'.rrnn-unrrdnr.rr:Jl{rfrnrhcrnnr:srtt tpap llvrrf
un:{quodoroilrulfi{ilrurir1e tfinorn"r{rlra1unr::Jiun'r1fird'rrirnrdd t'tppv

s. Inufl'rlil dr{:-hucououo.rrhrnr:1d ruppv fnno!f,uo{nlalurrnr go urfifir t dr1l,r
(!'rnfl!o1onor,!r1ro.rdr6'r z 'fr1l.r1 firnrmn'.r t-z 'fr1l+rdr{ilrulrinorcuo,,loionr:td ruppv
niu nru'hrir rydouurnd, fi',ro',:nrulclnu'tinfirurdo accessory vis'ldndrurdofion (abdominal

paradox) riln.rfi hypoxemia dol'ldriotirurru'lcuodirnlosiruuru'lenruJnfin'ufi
a. fir{rlrufintvdudtrinln:n'ld Nppv dolilld nju rir'hrdufioq".rmv 6on nio acute

coronary syndrome fi oo'ldriorirufiru'lcunddrnloorirunrutrnrtJiJnfi fi'ufi

Irrrrd uno{ihr"udliruru'irnr:1d tlppv riros :coufl odr rSl"'

Prediclors of success of NPPV

Young€r age
Low€r acuity of illness (APACHE score)
Able to cooperate: betler neurologic scor€
Able to coordinate breathing with ventilator
Less air leaking, intact dentition
Hypercarbia, but not too severe

(PaCO. > 45, < 92 mmHg)
Aoidemia, but not too severe (pH < 7.35. > 7.10)
lmprovemsnts in gas exchange and heart and respiratory rates within first 2 hr

SANGEErA MEHTA and NICHOLASS. HILL Noninvasive Ventilation AJRCCM 2001;163:540-77

Noninva.sive Positive Pressure ventilation ron:Tunf nfrfrrng 465

R1?c[il:nfrou (complications) flnn1Ttfr NppV

ntr: urrndouernnr:lfi ltppv n:idriou dtrbr!dlr{lf,n-lnr:ldyrjrnrn LLfly ventilaror

airflow pressure druln{uufluerynuor fulxnrfluuHo finrr::Rrur6o.rtorr8o4 (mucosar pain)
d:Jrn na unvo4n f,rrr:nio.:fi'u'ldlnunr:nnruaruion,illi'lfiuilurfiul:J ifivlaerirruror6n:a,r
tud, udgnnor,l'uldiru dtunm;urtndoudnrLrioulduri nrrndrdunl (ctausrrophobia) n'n? n
(nasal congestion) :Jronr (eye painl :Jrnh.:,ooun (paranasal sinus pain) rfiolrrfi,t lmucosal
dryness) n'nltn1ut6o.,rfiqr (eye irritationl uorot'lun:: rur:oT11T 1n {gastric insufflation)s

nrr;ur:ndoufi:uurofivlildriouuln lduri fian nr:qnd'rdn (aspiration) ua:ar&lurdo{ iloo

(pneumothorax)3es

fi:J

nrt'ld ruppv rflu6nrr,: rdanyi!,rlunr:drrrn6ofirjrufifinr:firfl'lcdrrrnar d.rnr:'ld Nppv
oc ::arfl odrrfrniu.rlflf'uduadfiunr:rdan{rJru nr:16onrnia.niruurutruava rln:nidtd'lu ttppv
n1:6onr rfl1:citunvnr:rloofiunrl; un:nfou flfio1:Iiluronar:r1rgunnrtrdl arrr.rrdrlelu

frroirrl mrirde;d.:nntfidsnr:onfiinroa{rhun{ldq.rdu finm: urn:ndouaoo.: rrnrlunrroai
T:trrrrrnnnnt un ynn dt'lddr u'lunr:inurvrtrrrr n

FESPIRATOFY THEFAPY DFIVEN PROTOCOL
FOB CPAP AND iIIV USE IN ACUTE BESPIRATORY FAILURE (ARFI

l. Patient Evaluation
. Review history. diagnosis, inclusion. exclusion criteria and discuss with MD
. Ascertain whether new NIV us€ or an accustom€d Datient
. Assess for component of chronic respiratory lailure

ll. Indications and Goals

. Choose as p€r patient diagnosis. level ol distress, and whether ICU based
o Decide options in event of early benefit or poor initial response
. Reaflirm code status and patient prelerences regarding alternative therapy

lll. Location

. Detsrmine observation and monitoring needs per patient condition and equipment used (a

step-down unit may be appropriate lor single organ failure or patients clearly recovering trom
multi-organ lailure).

lV. EquiDment Conditions, Initial Settinqs, and Tarq€ts

. Airflow generator

1. CPAP. Presumed obstructive sleep apnea or cardiogenic ABF lor target of improved SpO,
and PaCO,

466 rrrniliolnrlndugru

2. Portable Bi-Level Device. Acute on chronic component for target of improved PaCO,
and reduced dyspnea using visual analog scale. Use with portable battery attachment for

transporting patients-

3. ICU Bi-L€vel Device. Choose for patients in lCU, more severe distress in emergency depart-
ment, or poor synchrony and need for wavefrom monitoring

4. Full Service ICU ventilalor. Severely distressed patients with poor synchrony in considera-
tion of pressure or volume control modes

. Ssttings

1. CPAP. sst at 10-12.5 cmHro and titrate as needed OSA or dyspnea
2. Portable Bi-Level Device. Initial EPAP at minimum for neuromuscular disease oatients. 5

cmHro for others. May increase EPAP tor OSA component or for hypoxemia Attention to
auto-PEEP, which may be counteracted by judicious use oi EPAP, Inilial IPAP at 8-'10 cmHro

and target patient tolerance. Increase to 15-20 cmHro as tolerance allows tor relief of

dyspnea and respiratory rate.

3. ICU BFLevel Device. Same EPAP ad IPAP issues as for portable device but may need more

aggressive tiitralion as situation demands, Alter flo',v rate, sensitivity and inspiratory time to
optimize synchrony-

4. Full Service ICU Ventlator. Same issues as for ICU Bi-level device but mav consider use of

volume conlrol and other modes.
5. Orygen. Guided by distress level and SpOr. In those at risk ol worsening hypercapnia on

CPAP. maintain between 88-90o/o.

. Masks

1. Nasal, Ulilize for less distressed patients and those with chronic component. Also consider
nasal pillows tor more claustrophobic patients

2. Full Face Mask. Patients with severe dislress or larqe oral air leaks

V. Mornitorinq

. oximelry. All patlents.
. Arterial Blood Gases. Baseline and discharge ABGS highly recommended. Useful for ICU

patients needing frequent monitoring of PaCO2

. Ventilator with waveform monitoring for poor synchrony problems

Vl. Dismissal {Education and Communicationl

. Anticipate early for patients with chronic componsnt
. Feview for diagnostic and reimbursement requirements

Vll. NNV reqisu,rrloximetrv (recommended but nol obliqatory)

. Documentation. Log progress and outcome for luture patient use and protocol quality

assessmenl

' Reproduced from Gay, PC. Hubmayr. RD: "Mechanical ventilation part ll: noninvasive" In lrwin

and Rippe's tntensive Care Medicine 5h ed. 2003. p. 647-60.

Noninvasive Positiye Pressure \-enrilarion antanl nfrfrfty 467
NPPV lb3 Acub R.3dr&ry F.llurE

Crdlot.dc Pdno|rtt Ellod.tor 3.r.r...Ndab (!+l <?2)
hrmonocqmttl..d G|[fpr coma |c& <lt
F.[td.66.de{r, Poat{pjanf

A,'$|' for posllble chrsnlc ptb Dtal cffilq

hypryanll|don or O8A consldrr shoit tri.l tof
Dlschrrge phnnlngi
rcut h€an fdur€TCOPO;
porslbl8 panrdv€ lher4|f

eqrt'lrD-tnrbdt{c|r..edb.nlnr-txdioltvhnrFtJhttLtatp}t}i.Prn6Vrry..thalool{pcdfhodb.t.olhli
mriynE*nd*chdb||Fr|lodsfoaittc|€itfl|cr|uLnrtlbo*ahrrr6rardq3uridnlnro.|.l.*|d|lodtf|.|ds.|bhaPo.Fdl,[r.

b abo rr|ontUr ar i gdlHiy| ttftr|lnt.

..Huliii 1 ufinn,f4xnlnlunllgun{Jtl?ai'1rt Nppvs5

tanflf,d1{6{

hty1. Staufer JL, Olson DE, TL. Complications and consequence ol endotracheai intubation and tracheolomy:

a prospective study of 150 critically ill adult patients. Am J Med 1981;70:65-76.

2. Fagon JY Chastre J, Hance AJ, et al. Nosocomial pneumonia in ventilated patients: a cohort study eva.luating

attributable mortality and hospital slay. Am J Med 1993:94:281-8.

3. Brochard L, lsbey D. Piquet J. et al. ReveEal of acute exacerbation of chronic obstructive lung disease by

inspiratory assistance with a face mask. N Eng J M€d 1930:323:1523-30.

4. Brochard L, Mancebo J. Wysocki M, et al. Noninvasive ventilation of acute exacerbations ol chronic obstruc,tice

pulmonary disease. N Eng J Med 19S5:333:817-22.

468 rrtdrrTnlnqotdr,rgru

5, plant pK, Owen JL Elliott MW. Early use of non-invasive ventilation of acute exacelbation of chronic obstructive

pulmonary diseas€ on general respiratory wards: a mullicer{er radomised controlled trial. tancet 2000;3351931-5.

6. Gumersindo G6nzalez Diaz, MD; Andres Cardllo Alcaraz, MD; Juan Carlos Pardo Talavera, et al. Noninvasive

positive-Pressure Ventitation To Treat Hypercapnic Coma Secondary to Respiratory Failure . Chesti 2005:127:952-60.

7. lnt€rnational Concencus Conterences in Intensi\,/e Care Medicine. Noninvasive po6itive pres$re ventilation in acute

respiratory failure. Am J Respir Crit Care M€d 2001J 63:283-91

e. Fernandez MM, Villagra A, Blanch L, et al. Non-invasive m8chanical ventilation in status asthamticus. Intensive Care

Medicine 2001 :27:486-92.

9. Holley MT, Morrissey TK, Seaberg DC, et al. Ethical dilemmas in a randomized tial of asthma treatment: can

Bayesian statistical analysis explain the reEults? Acad Emerg lvled 2001i8:1128-35.

'10. Rasanen J. Heikkila J, Downs J. et al. Continuous positive airway pressure by face mask in acute cardiogenic
pulmonary edema. Am J Cardiol '1985i55:296-300.

1 1. BeBten AD, Holt AW. Vedig AE, et al. Treatment of severe cardiogenic pulmonary edema with continuous positive
airway pre$sure dellvered by face mask N Engl J Med 1991:325:1825-30

12, Mehta S, Jay GD. Woolard RH, et aJ. Randomized. prqspective trial of bilevel versus continuous positive aiMay
pressure in acut€ pulmonary edema. Crit Care lvled 1997125,620-8.

13. Levitt MA. A prospective, randomized trial ol BiPAP in severe acute congestive heart failure. J Emerg Med 2001:21:

363-S.

14. Pang D. Ke€nan SP, Cook DJ. et al. The etfect of positive pressure airuay support on mortality and the need for
intubation in cardiogenic pulmonary edema: a systematic review. Chest 1998;114:1185-92

15. Contalonieri M, Potena A, Carbone G, et al. Acute respiratory fuilure in patients with se\rere community acquired
pneumonia: a prospective randomized elraluation of noninvasive ventilation. Am J F€spir Crit Care Med 1999:160:

1585-91.

16. Jolliet P, Abajo B, Pasquina P, et al. Non-invasive pressure support ventilation in severe community-acquired

pneumonia. lntensive Care Med 2001;27:812-1.

'17. Bockef, GM. Mackenzie, MG. Willians, B. et al. Noninvasive positive pressure ventilation: successful outcome in
patients with acute lung iniury/ARDs. Chest 19s9:115:173-7.

18. Hilbert G, Gruson, D Vargas, F et al. Noninvasive ventilation in immunosuppressed patients with pulmonary intil-
trates, fever. and acute respiratory failure. N Engl J lved 2001:344:481-7.

19. Crawford SW. SchwarE DA Petersen. FB. et al. Mechanical ventilation after manow transplantation: risk lactors and
clinical outcome, Am Rev Respir Dis 1988J37:682-7.

20. Beltrame F, Lucangelo U, Gregori D. et al. Noninvasive positive pressure ventilation in trauma patients with acute
respiratory failure. Monaldi Arch Chest Dls 1999:&109-14.

21. Finlay G. Concannon D. McDonnell TJ. Treatment ol rospiratory failure due to kyphoscoliosis with nasal intermittent
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22. Bach JR eds. Conventional approaches to managing neuromuscular ventilatory failure. 1996 Henley & Belfus.

Philadelphia.

23. Bach JR, lshikawa Y. Kin H. Prevention of pulmonary morbidity for patients with Duchenne muscular dystrophy.
ch€st 1997J 121m4-8.

24. Nelson DSK, Vespia J. et al. Outcomes ol do-notjntubate patienls treated with noninvasive positive pressure

ventilation. Crit Cafe lvled 2001.

Noninvasive Posirive pres$ure \.enrilarion Lln:runl pfrfrtr1g 449

2S Matte P. Jacquet L Van Dyck M, et al. Effects of con\entional physiotherapy, continuous positive airyay pressure

and non-invasive vefltilatory support with bilevel positive airway pressure after coronary artery bypass grafting. Acta
Anaesthesiol Sc€nd 2000:44:75,81.

26. Auiant l. Jallot A Herve P, et al. Noninvasive ventilation reduces mortality in acute respiratory failure following lung

resection. Am J Re6pir Crjt Care Med 2001J64J231-5.

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721 L

28. Girault C' Daudenthun l, Chevron V, et al. Noninvasive ventilation as a systematic extubation and weaning technique

in acute-on-chronic r€€piratory failure: a prospective, randomized controlled study. Am J Fespir Crit Care lved

1999:160:86-92.

29 Keenan SP Povters C, i/coormack DG, at al. Noninvaslve positive-pressure ventilation for postextubation respiratorv

distress. JAMA 2002:287:3238-44.

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20033. Mehta S. Hill NS Noninvasive ventilation. Am J Respir Crit Care i,4ed 63:540_77

34 Kramer N, Meyer TJ. Meharg J, et al. Randomized, prospective trial of noninvasive positive Dressure veatilation in

acute respiratory lailure. Am J Respir Cdt Care Med 1g9S:1S t:.l7gg-806.

35 Caples. Sean M. DOi Gay, Peter C. Noninvasive positive pressure ventilation in the intensive care unit: A concis€

review. Critical Carc Medicine 2005:33{1 1):265i -8.

470

26

Weaning from Mechanical Ventilator

iliat dn,ilnlzati

rnia.:rirurrderfluq:Jn:niiiinrudrdqtunr:inr*r{rlrunrr:inqn {fifintvnr:rrulo
drrrar16ornniu uanqtnc:inurntr; fiutrq nr:tdtoia 'rrjrur'tralofifla'jrfidrudrdqoianr:

:yniu :vna.rnr:rir.:rutordrrnru ttnvrti"irlfiufio*dr'lonr:rir'rrutatqrln:nirvrirdrfluorir'':6
ruoi{iildrnda.rrirunrulaEj.:uru frij.rrdurrionmc!rn:ndau rtju nrrfin rdoiidlr'liuff!nr:tdrnio.'r
ri':g ru'h (Ventilator-associated tracheobronchitis and pneumonial rfinnr':vamld'uTafinrl"r
firan:vvrnirnrrdrmuao.:oiut;rir't1 niu ln ri'rto fi.rn::riunr:rir{rJruoonorntnsoodrlvrsh

fi'lrirvrrvol firfrurtqlfi{rJru rflu{gianrrv0-uo:ru niu nr:n'or4'oturloo nrrv rvirlrJoold rdu

fi'l n{rtu uanqlnnrrrflunr:'ldrnSoorjruvrutlrrd? uurrifilirnr::"nurdt'irriudo.:ficrrtrflunr:
fi or:rurnqntdrniortjruvrflleodr.Jtv rvor:firu

:-ryrnrrrdfirfrarfruda4orfotfiu'lunr:drt6':to':rinfinurtt vrtirra:rrvr ricu'lrrilirh:nol
nr:g uof,ilra'lunr:rtjr rniattirutru'lc Toulfluo,rdol f;fidrrflurrn:llururiltr{rdrlei1u tfiorflu

i{"u gr utun r r duntr rfi ru r6 r ri ohl

flqnrto.:nr:rtdrm6o.rdruil'lste (weaning process)

nr:udr rniartirutru'lq tflun:;urunrrfrfinrr:rdrdrp:;u;trornr:lfiuniata'ttu't#iut*t',t

rfiurra{lrfufunoud nnirr6o l::rrruioun; 40-50 oro,r*rr"onrofr{:-tru'ldrnia':riruvrutq

td-hrrrnr:ndrrerio,r uanerndruilr.lt:r.trrutoun; so torfitrufro''rviavflaafl no (endotracheal
rube) 00nr0\r nril11nrrfltqlfr'Tnil#o.rtdrionrf,'illtril (reintubation) rrenttfrrfiuir eirunfi'l
ao.:firJruorotdroia,:urutfiuntrrdrtflu drulttqrunf,'rnnim 6tfinr1ltllururffio:uri6d6fiqolu
nr::J:vrfi unrrrn5ounrirrnio,rta,rfi rhu

Weaning from tr{echanical Vcntilaror tJisn in tlw[nd 47L

irdrrinaerilr,o\: weaning success mt weaning tailure

r'r n nrrfi nc't dlu'Ifi {linhoir rYonr r ln-ld

w€aning success firJ1ufi,i fi ruar r:o11un't$laia.:tiruyru'le*osflonviot4ffoanrJnaoafl

(extubation) ld'loulrjchrflufia,'Jtfinr:dramru'lo (ventitatory support) 'ln1 nrulu qe ri.:llruo-.:
n0nra

Weaning failure uuruflt finTl:lonrryvdtsiolll:

1) Failure of spontaneous breathing trial (SBT)
2) Reintubation and/or resumption of ventilator support (txr,fi\:n.t:1d Non-invasive

ventitation 1t'ttv11 un'rnonvionnonRrJna nru'lu +a rir1ut

s1 rfi ufiinnrttu +a drlrr-r yfl-.:naoyioynoonrno

rfiolcrnfinrtld Non-invasive ventitator 1t'ttv1 rrilrrndl {rhudtund,,r orqnnnon o

nooa nor".:fif{e'rrflufiortdrn{aui'urraha{ ua:nJduur:rl$ ruv uvru 6unn{rdrflu ..weaning
in progress"

.Failure of SBT l4rJ.rufi{ {n'1fi:ilnr:vrh SBT rflutrurr?fl1 go-tzo urfi udrbirir l5o
Failure of extubation (Bdubation failure) fi tufi.r tln"'rnaovlottnanatnorrdr firhu
irrfl udarldiunr:tdviand'l dr'hfluri nrr'lu 48 tirl .:yri.rnoeryiotiruyrule

lui yl.a. 2548 firiis?flru' lduri.rrYunounr:nun{rhudldrnia,:rirarrutqriu 6 :vuy

lstasesl ldrri 1:ild t1

1) Treatment of acute respiratory failure 1nnf1 riurir-rii1finr:fnrrun;fruy.lanrr;d
rirhi rfi ornrr vnr:nr uh fi l ry nreurfl u rnqlfi fi o,rtdrn4o.,:drunr u'lr

2) Suspicion that weaning may be possibte .rfumaudfio,jrd duurauyirdufiuirfinru
rfluhldfr {:lrurjrocyEjrrnio,ilddrr5o (weaning success)

3) Assessment of readiness to *ean riumaudiirfiurfi'a uuvrtirir.rnr;lrunr: :yrfiu.jr

{il'luntorrflrqi weaning process un:fi'uqnria rir.rrir ser
4) A spontaneous breathing trial 1Se1 nr:rir Sef fiolflunr:GrJdu weaning process

5) Extubation fl't?fi0 ayiflfi n 0 ontJ 6oaafl

6) Possibty reintubation lufidlrjorm:nnratrldrol arrdo.:tirianni:.rrdrhflnri

ortrqdtririfi lfi nnxrtrilddunl:yri'lrnia.:drurru'h (detayed weaning) dnur-iou rfi o
em{inu1fin?1il6ird{unr:oiurdrqirYunoufi 2 uny g olusu n"rn'llYunouryeirddrurf.rrdal.jr
n'l:rirfiunrylrunr:nrjrrniaotirlyrulqlnfl r5r 6n ns.r Ei,rdr u'h1{g ua n rrl r: nrir n r:y rir rn?o rtir u
nra'hldrfluohd'u wtaryr".ry'rdrrnRun:ufi}rldatirrrflu::uu

472 rrtdrfinlnqmfilSru

1)'oTfrAeaRlmFent 3) Assessing I s) e*tuo"tion 6) Rejntubation
readiness

to wean

||2) suspicion l+l ser

Admit I Discharge
I

tnJd ugmvitnaulun'nguafiJauflfitaia$hamalc 6 TJav ARF: acute respintory failure: sB7

spontaneous breathi ng trial

nr:J:vfillar1iluisilianr:tfi1{n:vurunr:udrmia{drs$ru'le lProcess of

initial weaning)

:rfl wfrum oufi rfi erdurio rdo,rcrnr v u:fi z l ot nr:ld rn{o,rdr uvr uto'hrYuduvrn driurir nT

rJ:;ul'uorir,: rfluttrr-ruau rrriildrflu z rYuotou 6a
1. Assessment of readiness to wean

2. Spontaneous breathing trial (SBT)

1. Assessment of readiness to wean 1nr:r',:# t1'

rfunoudflorflunr:cronra,tufiorl:nfiunrr tiousionlrytnna.ilri{r1rurrulo ron (screening

test for weaning trial) rfia'lfirfionrrun'utc'lunr:liriYutdo}J fia ser dlfiotflu confirmatory test

rotnr:rir screening test flrofiu tu;tfiurriu ser fi riiu screening test drvilnrll::tfiu

nrulSorc{onr:nonrionoonalno (screening test for readiness to extubate) tJ::noldrl
1) Clinical assessment tflunr:l:: tfiulr'tnfifin
2) obiective assessment (weaning predictors) druluqivrl'i'r parameter rndrd fi

sensiriviry rny specif icity lli4r {rLruirnlririrulr,:tnrud areytjr taiomirlyru'lolddr t5c tfiallrn
arrr.ruriudr'lrjurn {rdurtrrylr,:viru6,:tru;riT 'jrorqlriq'rrflufia.! :crfiu predictor rvsjrdrrritri
narrh sBT rnu odr,':l:frprtr tirricr:rurirlniu clinical assessment etd?u'lrtnrxo r{ftufllri

rrl.r'r;lirnrryrirrcriattirunrutqaEir.:d'n rlu iaa're'ldi!otatduornnr:aa,ivrulclatlddjn*u fu6o
rirfil:rur parameter rueirdrdur"l nru rt{io6oo;n'r rroiurnld{}Jrilnr:ri::rfiurrln6finudr

arrr:otdriruun{rJruiffTonraq,roia failure to r""n 1d tufidovaansirrfitri.rfifiul'firrn:drlfi

lilarnrin 60 Bapid shallow breathing index (BSBI)

\\ieaning from Nlechanical Venrilaror tliat tin nT:i'fi 473

1n1fl{fi llflo,t Consideration for assessing readiness to wean

Clinical assessment Absence of excessive tracheobronchial secretion
Resolution of disease acute phase tor which the patient was
intubated

Objective measurements Clinical stability

Stable cardiovascular status (i.e. fC < j40 beats.min-r, systolic
BP 90'160 mmHg. no or minimal vasopressors)

Stable metabolic status

Adequate oxygenation

SaO, > 90% on < FlOr 0.4 (or PaOrlFiO, > iso mmHg)

PEEP s I cmHro

Adequate pulmonary tunction

tR S 35 breaths.min'1
MIP < -20 - -25 cmHro
W > 5 mL.kg'
VC > 10 ml.kg
/TfR < 105 breaths.min '_L'1

No significant respiratory acidosis

Adequate mentation

No sedation or adequate mentation on sedation (or stable
neurologic patient)

rc: cafdiac trequenry; BP: blood pressure; SaO?:arterial oxygen satu'tion; FlO, inspiratory oxygen fraction: pao::

arterial oxygen tension: PEEP: positive end-expkatory pressure: fR: respiratory frequency: fulp: maximal inspiratory

pressurei W: tidal volume; VC: vrtal capacity. I mmHg=o 133 kpa.

Rapid shallow breathing index (RSBI, fR /VT!
yN'rufi.r drdldelnnitfraint.tnl?yluh (fR) yil.turflu nf,:siourfi trrd?u ridat volume

1w1 nilrurfludc: iorirdra spirometer lurru:fifi:Jrunrato lo,r rfllrrnrodr,niau t urfi rirfild
> tos ni.rriourfisioFmr ilr'irfiuudriilficvrdr rn4o.Idruvlltahi6i1r5r rn'nnr:ro.r Rset 6a rfro
nd'rrldov'uhzo.r{rJruoglunrrrejaufir d,rrolfi:rlur:.rnr:vru'lo r duucrnrlnfi rflunrryrrtlrir
,rovntuo*, rirtfiririin:roldfirirg.,odu o1u"u rir nser ii,rgr rfi,,rnr:mu'lor5r*n:dumn d.njr

q v ffilvfu5fl!n'trNfi r rynrr ar nr:nti'r rn{0.:drunr utefi ilr nflju

nr:indrda,,rrirrnrvfiurruarunr:urutc @reathing pattern) rlonft-lxun,lfirrdr rdo.:o.rn
nr:druyru'lodlurnio':arcl aonr:rir':ruqrn respiratory motor output rirlfi{rJrunruiedr
run:dun'irdrfluci,r iirr.r-nrfiotutir.:1urfiur:nrn'.:nr: norrn4o*rdrry.ru'lo pr-.ru'uuircultridrrnsl

nr:nrato{ilrulfin.:frriau5.,ruhnr::J::rfiu firldnorilrrlrru i urfi rn-rmnfirjrur?llrnutcro.,r

474 rrtdrrininqmdlgru

dor,{',,1:sfin6n!.1:sn1?yd.r 6o {:jru::r,lrTadfi fR/vr > 105 oreorur:ovdrtnCo.rtirt lulc
ld lutru;iur,:muufl tRAfi < i05 fiflEj1oonclnrnCs.:lild1rie ie{aduffiaraoiad'r RSBI ttju
alr:innfi'rta nrrllr6:lrJro rioynoonrturor6nfiu}J }n:londfia1jt6tJ Yi'luouy'r'lu c;lhtfi{eld

fi'r RSBt {.rdu nr:iqtulru:ld pSV fiio Cpnp r5o rfi':nonaancrntnCordrutlru'loliluru cr
rirtrlldrirn'rn.: a''rriu lu{frrir RSBI {n rdnr:ricr:rurludrudul rtiu nr:rJ::rfiurr,rafifinfi
nlrrrurr:f,rdon',rno.ttn.ulc,o.t lnu rorrvflrfirrqoilrunr:firir Rset 4orltu uurfarono't

rJ:: riuri:Jruh'ir"uri oUlourir ser 1d

sraolldofier:rur'lunr:rltvtfiunetrntarto,r{rJruariri'jrul{ ::nr:' 6o

r1 crmqdrhlf,gil':a'ldtis aoanruncliralo.triasilruhidunionruudr (re:lrifi

nrqtnrirfiniu6nlldfiioor-ofrunruri'r'jr{rJ'lunrtrdrfiuoloftnorc?drtnio..l dua{fi'uqaufifillo,:

ruvruJrfludrn'rp

2) Putmonary rcserve tfiu.r o fi.r:cfin'jrtirlrifieirloril6urdrrriudrrfiu"rto'lun't:n'odu

g) lrifiioft xilioqrJa::nionrorrrletoomnrsu du'luonlsulJtlltllru'lo lnon-

respiratory factorsl d,,roredrnro'hI{rhurru'hra,tlrild nloldlriuru nmvrtvr:ntoutnsirio:rfin

u.rnl'un.l:turrrnrii{r]ruldrniouiranra'lo udfn'lri'hi absolute contraindication niailli'l
{r-huo:ndtnio.rhidticodr,:rtriuou d,:riu rnruforqrirnr:rrfiltbuior.rl fiutiln:vltunt wean

{rhu nrr:rnrirflduri
g.t) icr-uddlnnn:ltleio respiratory muscle strength and endurancelduri n'r:rdu
crqo:ra',rrnfi aui triu :vq'rrn6oltr6ur.rlnrurariullurfiooq.triooir nrrvtroorrn:

nrriLl:fiun'r

3.2) fl e{uddnilfl ntyfludo ventilator mechanics niu fi o.r6nmn firir1udo,,:onn5o

rio.:r{oo:Jir.rrrumn nrrrtSlr.ho nrrturlrir

3.3) Acid base disturbance

3.4) lncreased metabolic demand tdu l{qo ornr:uutdu nm:fiqlds nr:'[diu

0'rn1:n151:iatnrorlilrrurrn nT rclil:oudtflufiu

3.5) Abnormal oxygen transport mechanisms niu nrlrTafinor.t

3.6) other organ system dysfunction nj! nrrc'lnmu tdsnoonlrotauoryl: nlxv

n1nu1fll0u1lnu

2. Spontaneous breathing trial (SBT)

vrrafi.'r nr:rnoo.:'1fi{rhunrutcro,'r ldstirufilrTu 1ln-tflnril screening test'lu:vH;fr

sf ir{rJrurjmvr'ffrdfl::ltunl:n0qriavnsernunold firnluii'lduri r-tuot or T-piece trial.

Pressure support ventilation (PSV), Automatic tube compensation (ATC) rflufiu tuddc:10

nrir r fi r ao,: iE u: J o r6ih, i6AAfrlail ur t rYu
nir-
Ld

$i'eaning from trlechanical Venrilator tfi,v't thrilxTnd 475

1) T{ube or T-piece triat 1fi{ilrunrdor0{r.jM'l,i t-piece doruaanfnunllrdrdl
rrirdlniounn'jrnidrJruldo{riau r ox

2) PSV with or without CPAP - tfifiilxufilute ro,rdxfl pressure support r:dlnrrl 6o

5-8 cmHro Tsrurdo'ir pressure :ydudl:rn rtun-u.r'rufr6otrartuJu:{fiuqrrunr:firu'loiru
riovnonarna n",rd orctfr cpAp (pEEp) -lrirfiu 5 cmH,o drllr{ruriohifild

ui'jrnr:ld pSv orcfida6in'jr T-piece triat luu,inrrrr oonriu n'rnr;i monitor uo:

::rrrdoufuqrn laia.:rirunrflledrufioorrrfiilru arjr,rlrfrnu lriulnrtrunnra'rt'lu adrrfee.tn
n'rrli'l sBT d?uda.ri6dr.,:du rnzurflunr:firr:rulirful, arir ser drr5?viadilr ox n",Jn1i1{d 2'

vu d'n:r nr:'ldviar'hio uo; t a 1u {rt, udrir sBT dl LSc ufi .l noqyioraoor n tna lfi ulnir nr:
noprrialnulrildfun'n ::rfiu sBT dou fia-n:rnr:'kiriauaaonrnorYrfl,,rrjr:rrnriaun: +o n-,rriu
nr:vrh s BT c',rdr fl : : rfi unrrl dr rSrla,rnr:n o ovi al a a nn:.r nold

:ssyr'rar1unrfl/ir sBT 6a nslrd so-tz0 urfi uoirfiil ser'ldrrnrrird z riilil{ udcrn

nr:frnursio!rvr!'i1 nlrdr SBT g0 u1fr druruarrrdrrillarnr:urirretio,:druy'rulcldki[fin

ntr.rd Z ttf,Fr{ Failure criteria of spontaneous breathino trials

i Clinical assessment and Agitation and anxiety
subjective indices Depressed mental status

Diaphoresis

Cyanosis

Evidence of increasing etfort

lncreased accessory muscle activity

Facial signs of distress

| *"0n"" < 50-60 mmHg on FiO, > 0.5 or SaO, < 90%
I Obiective measurements PaO, > 50 mmHg or an increase in PaCO, > 8 mmHg
< 7.32 or a decrease in pH > 0.07 pH units
PaCO, > 1OS breaths.min -.1-'
pH
> 35 breaths.min'l or increased by 2 50%
fRNT > 140 b€ats.min or increased by 2 2o9r'o

fR
HR

Systolic BP > 180 mmHg or increased by > 20%

Systolic BP < 90 mmHg

Cardiac anhythmias

PaOr: art8rial oxygefl tension: FiOr: inspiratory oxygen fractiont SaOr: arterial oxygen saturation: PaCOr: arterial

carbon dioxide tension: n: respratory frequencla W: tidal \olume HR: he€rt rate BP: blood pressure 1 mmHgJ].133

kPa.

476 retdlioinqndu3T u

sir.:d':r rzO urfi un:{dtilrjru SBT (SBT taiture) fnrfiodulu zo utfiu:n d'triu unvrri{ri'rnr:
::rfi unrrc:'lfinr:gun{rJralnd6nns{uoirirlu:ntolnr:ni sBt

arudtunr:rir sBT nxrr'1tifiu,:iun:nit ndrrfio fir{:Jrunjru ser ld twlrfficr:rur

nonriauaaontna uri:radrir SBT ufirdltrar unvrtinrrda{rhunirrnio.lti':afirulq rrdrlfi{rlT u
ldiilnr:tiruvru'loatir{rfiuo o ({ull ventilator support) lrtorfr.lfiurr rrn; ufial w qddrlfifir rrar
fior:ru, rir set'lnrirdacrruqriul 6du lnurir ser1rrjluiufrollttovrfiu,triun;nf*rwiliu

nrrgue{rt'rudfu tta'mnnnrtir sBT

r1 nrrfid sBT fixrfin? {rlruntildirnr:rirufirulosiodrurnCa{tirutru'tq Inu'ti moae
PSV fi?o assisted-controlled mode ttiu Pcv v5o vcv fr1d lnrltfir!:hu'[d full ventilator support

rfro'hivr'nadr{rfiuunro udlrido,ni'rsurnfiucundrtirdonru'hLildrirl, urnu tn:1vorq finflat6lu

cr nnr :rll o eYrn o.tn dr il rdold

2) x'rf,'ll q IJ5JIJJU q! 'i
llnYun [t[110!u

fiMrerro{ SBT tailure oro u:j,ildtflu a n4ilr'rqi' 6o

2.1 mrurilunrrudrrndoatirunrulari,ilrin:l niu T:nn?onm;firir1fido,,rtdrnio-:ri'ru

r:fi r utc ri.rlil 6fltu ril rii n fi q n rn fi o rrd'tuir,: n r u fi n:J n 6

2.2 finrr:ttr:ndaurfisfulruvr,r, uloral tdu congestive heart failure rirtorduftndtvr;,

n1't;fi nonfl fl9tlnit hypoxemia. secretion obstruction viavnannlnotfi ounrn

n"ruuritfilvm:ar

2.g dolnniolrrltlRfinn" fitru;vrahto'r6o.rrir.':T uguriu niu vionnonnlnafituro

r6nrir'tficr':trdrurrutru:uruhto.:4,: nr:doviThirtr.rr:arrirlfiviafinr:rin':o cutt

oressur. c'tftlfifiornrfi+ioanornr.lo:lrhr.rdu ldnlr.r rdtiuto.roonfinulri

r14tJ1gfltJ

a) arar6iufirfioorn{rhuldrTrnr:drurrute rruru rrju ndurdorrute eioutt:.t nmrriltn

nd'r nrmqofirtrlorni;vru'leto'J (psychological dependence)

+1 fier:rurud, rnio{tirufiru'lc6n nollrnufilsortlqtoletrrr&rtnntusul rrdr nrrJ nfi
firnrm4rfinorn 2.1 uvirriorefio'i:arJrvrfiurnrudlfiRlry:nirrnduriou rrdr6,:rdu weaning 6n
n*,r firnfiorcrnrfi E z.z nia 2.3 6n?r1fiiun1:1ir sBT 6nun-rufi1t druiurnq z.+ nr:vdrrn4o'r

afioioliorqdooldi6riourfluriou1rJ (gradual weaning)

rJrvr6udrra.ryfrqntunr:li'r sBT 6a nr:6nnrr.r{:-lruadr,i'lndin rda:J:;rfiun'rdinnrtr

drriedrrl nr rnnrdurn;ifiea'unrrvur':ndoufr lfioduldaair.r:rnr5r ldofla,:liudusr:rurrnnrr:

ndrurdonruhrjauu:.r rvr:r;nr:l:v rfiuddrdrou{:J':reiaufirurnlfiu o:fr'hl{r-trufiottfirrnr

lunr:r{nfruurun'jrqcv{So iunrr :;tfiu sBT 6ne'i.t usnmnd'lu{drir ser udrdltror orq
rfiernrrundr riorn fioufi Tnulq r:'lu:rufido,: tti8ryrilntur:urulutuvrir sBt rriu nrrrf6ln

lf.'eaninq from \fechanical \. entilaror tfim rhz,in[so{ 477

elnnr:n1oo1n'r6fi1!ie a1?lftifilri8uuolJlil SBT dn miorfiorlqnrvn,rin'locurflua a::nFio
, a, ru.l,c1.tuoLir,n'ot
nlrfl lillfi
rjr rnEa,Jd?ufi

n11 nn6o, un1::h:rr^uurin:lYuardu n21roru:olardrhrlfiu (sensibte ctinicians) uo:

nrun3omotfi:irudi:.rnrfll:c rfiu noirrFa uancrnfi:Jruo;fiqrunrffivrtarnu rnrud'ufir uvryri

:y6u"rdoroqrlo{ufiorerirhlfiil':uorudn'irdrfluq3{aanlilriaun1r lfiuri nr:yuo rianonr:'ld

sedation oir,r1 ulu4iol4Irfvir{{"dr-rhrotrroj'{l'u'(tuaannrryvrrffiiri,rr,irouSlorilroio'nrn::rJ::Jy:: rrffiiulnrnrnfrfrqnn flnlnrl;irdt@uur'tnn1"u-l riouilnr:

:J::riu{:Jranr:ldvrhaiauotir.rrfiatna ri',,utu udnr:rqn sedation aredralfinrr ::riugnfias

l*u usjnr:"ld sedation rioal 'lurire riounr::J:; lfiu lfnriutir.rnnr.rFuunylfisraanqvrii#uyro

qrdriaufin rrnrrJ:: riul 6ororjru'lfifirLrul{r{nnjouorir,: rfiu,:ro I'jounaro ua:lrioriunr:

rJ:yriuldrrndu

n1?nofi doilaonailna (Extubation)

rflurrtnauaofirrto{nl: rilmia{d?u 1utefia'naa,Jflruhdrupirro.rdrrSo fida'ils::finir

{:lrrfrrirudr ser drrSe orqhjnr r:n ra'lc ro,rflfl',Jnoqyiooon qrui{r-hunorir ser drrfefi
d'n:rldviodrriounir{finanvialoulilrir sar finrr; d'rriuidfr.:iido.ril::rfiurfil16r.rriaunoqyio

ON LOLLfl

1) Airway proiection
2) Airway patency

1) Airway protection

erttlfilrt:n'lunr:io{rTuvrr{rduyrutolat{firrrnnr:drfi'n (aspiration) t*ufi':-rflc,i'u

drdrp s arir.r'lduri nluaur:ntunr:1a nrtr!61nfi'r uov Sururorlv; nr: ::riurl::noldru

1.1) ilrrtfiu Cough strength fifloruifi Lt!
i. Semiobiective scale - unr6 :: tiunruu:flunr:laudr ttri..rrfu 6 grade 6a

Grade 0 = no cough on command,
Grade 1 = audible movement ot air through the ETT but no audible cough.
Grade 2 = weakly (barely) audible cough,
Grade 3 = clearly audible cough,
Grade 4 = stronger cough, and
Grade 5 = multiple sequential strong coughs

nl'jr fiilrufr finrrru:rtunr:lariou (weak: grade o-z; fi nlnrfi a.orio extubation

Ifailure rflu rrirro.rfl.dlol{u:n:l1 nar.rfinm.,t 'rn (moderate - strong; grade 3-5}

ii, White card test - Iount:a"r file card il,raln nruyioynona no 1-2 rru6lrn:
tfi{rhilo s-a nil .irfi:ourilun (wetness) lfiordufi caro fia'jr rflururn (posttive white card
testl {frzualflu "ar" finrtldutrn'a extubation fatture rflu s rrirlo,r{ir'ornrflu 'lrn"

478 reudljninqadug'ru

iii. Cough peak flow - ta0"nl1!5xgtqo10{a 'rutoaanrlruv'ls r:l'ir {r.hufi cough

peak expiratory flow (PEF) < oo Umin finrur6iu,llio extubation failure tflu s M'tto.rfifi cough

PEF > 60 Umin

1.2) Sputum production - {rlrlfifiorurduneio extubation faiture q.rdu niu {fr

fiorgororr:rjou (rjoun'ir1n z rirTru), {dfiromv > z.s ln-rtir1l.l'r finl:lrdutrflu 3 tvi'tto'r
raa LfltJ11:U-OUfl't',,tXU
avr'l

1.3) consciousness lflu:loiudorofi arudrn'rpriounir'ilodu1 rdowrnl'udr {fr fi

clasgow coma score (GCS) > 8 nooYiadlLS? rnn'jrflfifl GcS < 8' adrtl:frsrlrfinr:ifnur

urir{ifi ccs < I fiorrnonviold d'triu fififinrrrfflnn-r6niro1c:J:vo:rnrtrdrt5q'lunr:noo
nl{fryiotir uv'r shrr n n'ir uoi{fi fi
nd'rlilalrg:nifi 4".: oronoervio'ldniuflu

:touucdr

. drn:-r {r-h u dru'lvqitrnvrun'nuru: tr sird orrtr a o nr:n a aviotirutrr u'lclil ri ou 6 o

lohju?{ (weak cough), GCS < 8. gotont:riounirrln z-s t'r1rj.l rfiomvrrtufilt
eauLl1a,1ulotf-idftAflu

. rlqfliuri,il!firnruriduriudrtunr::v:1ir{rJT uloo:hif,rrrrn0anriovoaernraald
. firud4onr:fi'nfiu'lcnonyiarflufiirdtoturrr{{qunddo.rtJ:crfiuuavficr:m{:-lru

rflulur l:J

2l Airut/ay patency
vrr*6unrutoldrdnialri nr:tdvionoooornodrlfiii laryngeal injury unr laryngeal

edema'ld u:{'hdruh{{r-huc;fiornr:'lrj rn triu ::ntuna rfiu{un! *si'lu!r'::ru {rJruo;fi
mrrtdunruhqnniurfint*unruv{tognriald (postextubation stridor and ainnray obstruction) i6
n:rcfifiuil6o cuff leak test rflunrrnrrc?rnrtfrnroooniru:vwir.:viovaaanrna un:rr{ tduv'tfl'le
drudulnr;d{:Jrurrutooonun:qnnrJoanqln cufi udr ldrirura postextubation stridor ![o;

reinrubation finrror:rqld z ulr'lnrg1 6o

2.11 nr:n:ro rfi.,:4runru 1S stethoscope t{,,ruitrrurr.,lt6unnoonl'lrn{druu (upper

tracnea) firflili'tdrfiu{a aaor.jru 6o'jr Cuff leak test fin:Jnfr

z-21 nr:n:mr6.,,:rJimru ia ir.rrrunuiriruoonrr::uirrviaroooorRauavmrudu

yrutcdrufiurnnrd'n"nfiufiri,:rfluilimerornrfidicildqirtficir'1i0rn.uuiarlS rn:fiorflu5oun:

ro.l expired ridal votume pJir.nn:sirudniruvio; tdririaun: te-e+ ludruoinr:finur1 {rJe#
vrr16uvru'lqdrulufinr:qorYu rvioei'rlddrn'jrrnnrd iir.irvrfiuri.rnr:rld zu

ilco"ufi maodroa'lm:nri'r'hi cufi teak test lddlfiou loulrildlfi nnr.,:r6ufirulod?u!u
6rn,u ltju lfle]Ttlo1J"l yioxaaqnlno virto,:fi:u; unvna ?urqlo,:viotlnoonrnotr.rqirfrurnirru'to
ro.:nria.or5luo furiu {fildrirriaaorqhjnu postextubation srridor fltd {rdartrrgr.nliruniu'ir

nr:fi cuff teak volume riau lrilfiuorodq:lfitvaonrroostviofifl0nn no rfiuo llpinr:llarrr

Veaning from Mechanical Vemilator t[lttt i.tz,tlwbod 429

n1r1,id 3 tlflq.riint'i-g cuff leak votume

Betore performing the cuff leak test. first suction endotracheal and oral secretion and set the
ventilator in the assist control mode.

with the cuff inflated. record disprayed inspiratory and expiratory tidal vorumes to see

whether these are similar-

Deflate the cufl.

Directly record the expiratory tidal volume over the next six breathing cycles as the expira-
tory tidal volume will reach a plateau value after a few cycles.
Average the three lowest valuqs.

The ditticiency between the inspiratory tidal volume (measured betore the cuff r ras deflaled)
and the averaged expiratory lidal volume is the cuff leak volume.

Edited frorn Miller and Cole [24.

4nrrl,rii uf, rNllodsrdu,reionltlfi oy].Nr6umu'lflJx

female gender, traumatic intubation,
age > 80 years. aspiration.
a GCS score < 8. insulficient or lack ol sedation
an elevated APACHE ll score

prolonged intubation (variabty defined as > G6 hrs to 2 6 days).
a small ratio of patient height to ETT diameter,

Ia large ETT (> mm in men. > 7 mm in women).

excessive tube mobility due to insufficient fixation.

r:fn::r".:rflurironlunmnooyiafinonarrna'3 driuuniu.ir culf teak test lfluflu n?:fi?l:ru1i.t
fi:hd'urdu0dusianr:rfinvrr.rr6urru'lo6rLri'uvlolri rirhififiriro;noorio usifirfiiq{urdu{6uirlldru

fi orqo:riqrr rr:aanl?nfl oyio [ny'lfinlrouninri riau rd! nrrtfidrfiu:ofl d rfludu

nrdflriFirf, aoanrianasonlno fi af!if.rJ,lrril5au"

n1:lrElnn'lr'lfi0rfi1lrn;drdulrdrn:: rlryoryr:urififraroc;ldi!nr:naoyio lflurrntorir.r
tiou + rir1uriounoovio (o'raulun'jrdiu:rufifirlqurfl,r:dau01r41i) {!ruarraeiiuvird:uvc,r

30-90" a1n[u?:1r norclJx:turiovnoofl n0 tia{ rn uocyr"},r raurrutcsiruru louyurulrgo

tc :oon'lfivrtfr rfio.rornrarJrrvl'firroaiua;hnnlnovn-.rernnaavio Idr arrrir'lfirfio taryngo-

spas. Id lrrviruuuvuh'hinrnlfloerrsrvvl{'luviodoufiqvnno oonolfl cuff u,rtaonro ficdru

dorrc:fir,rorjrrfiodo cuff unvlvao'rrnonnrfia-.refiff aanq1ncufi Lsriu qrjn:nilfioonfireu

480 rrrrirrioinqndugru

liotf,Survhd{illu o:rtflu rdu o, cannula mask mask with bag nr:1fioon6roua?'ltJd {u

4,: rfiuehrfluoro rflun'r:duttl6a{ rrnvlu:1udfin't?YnrSuouloroon'[tri'n'.:a{ t6:r (chronic co,
retention) oredrtlinri!oulnoonlsdn'ordldu6nld finnrl{:haodr.:lndficr il:lrfiun?1 611111?n

'hnr:flo.rriuvr*rrdumuhuo:n1fll1ulo {ilrtorofirfiu{ttfi1r:in'lur]o tillStlrudoo:Jrnmiano

ldlfiinurnrilornr:'lu:rrdfirfiu,:uvrurun'it z+ ridr.r{aredo.:il:: tfiunrrvthtrulo,tarutfil.l

dru ldo{ilrurruleldd loldu:,tila t-r tnnvvoonldto.l orrrifindrkjrtrint untforqtirarvt:

vnr rnlrioor rio'rnrr'Ifi otir.il:frsrrltu:rudtdviounanfl nfltJll.l'lu urrfartt:aonrrlfrortr:

n.irunrt r6uarrr:1:l ri ouqun'irc: rrillo'irki dottdvis nd'rhfl u ri

Failure of extubation (Extubation failure)

nlrufi.: {r-huc'lflufiot1diunr:'ldviafin0nn no nd!rd,l1r1lvri nrulu +g Tir'lrnvnononYia
rnnrri ::rfiun-tnrl,td s'arrvfitfioldlrn nrtt6uvrutqdruluqofiu (upper airway obstruction)
airuhdfiarnr:nrrLtu s-tz drk.:vii'onoovio, tf,llt'tctlitJrru:trn un:nrr:6u1 fitiluarlvmo.t
weaning taiture firiurrlqro.:nm:flirdurTu {rhun{rdrvfio-et:rnrurfllq.:riu lnad'ot:rorrulu
n4lfilrildfirnqornnlrfio:lnGtalvr.,:t6unruto (non-ainvay cause) a:qnni'in{rifrfiorrnqlr

mnrn{rfiuvru'lc (airway cause)

rlodurdurrionrtrdlrunrlunr:oaaiafiflanfltJna fitaruadrl triu nr:fitaut:tlimrurrn
ldrnio.,rrirgnrulo u'runi't 72 tir1l,l nruftnrjnfitorvn.rtdumu'lodrutlu tnad tflo':n"lnr:uri't

rnia.rrirrurulelndau Paco, > 45 lru.:J:ar'o

o'fi:rnr:'ldyioraonarnonn"lLlhr.rlu{!rud sar success fi:J:llrruSounv 13 dxu'lfiqj
{:l'ruo:vrutdd6duriorll nur:nnnun:nqonr:tfioonfirculd adril:finu ioua: z-ao c:fi
nrr:nrfl'lotirlrn (postextubation respiratory distress) tfindu rrn:drutfi,:fiottdvia{tr da
drnqfionr:rfio postextubation respiratory distress arqtfiqduvirtmnrrnrfinonialduru l'u'jr
farnv 33 to,:nr:tdviofrrfiodunrutu 12 ddr,r u:nvn-tnonvia Saun: +e rfinduna"t e+ rirLo
hlufir" d,runnoir.roln sBT taiture fi lfiodulddturitir.ru:n1 va'trir.r sgt

nrtr,lfi S ulortnrud:J:rtfiunl1v extubation failure

fR > 25 breaths.min j {or 2 h
HR > 140 beats-min1 or sustained increase or decrease oI > 2OoA
Clinical signs of respiratory muscle fatigue or increased work of breathing
SaO" < 90%; PaO, < 80 mmHg on Fiq > 0.50
Hypercapnia (PaCO, > 45 mmHg or 2 20% from pre-extubation). pH < 7.33

fr: respiratory frequency; HR: heart ratei SaOr: arterial oxygen saturation; Paorl arterial oxygen tension;

FlOr: inspiratory orygen fraction: PaCO:: arterial carbon dioxide tension. 1 mmHg = 0.133 kPa-

\S'eanins from \{echanical \,tntilator tliut ti'nilnhqi 481

arnflndl'rii'r0\:nrryeirraio,:tiruyrEitorirtficTlr:nciluunfi xun't nxr u'tnilurrn:tyux

rrorlufi udtoio.,:tjrsfl ru'lq Bsnldrflu 3 ndrr

1. Simple weaning rrtrfi.: {durirrnio,rtirlmutlrirrie (extubarion ld) ri.rLreifl SBT

n:{ttJn

yDifficult weaning 'rflfr{ 4'!,frfl ryn't lunltli'] SBT *. tHn rtF]d1:]ltnfid,r d \[,d
1650'l
Ft5{

lnui.i'un1rfli SBT trirRu 3 nli,n unr nlidr?R'trdrt rnaiar trl,r-irfru 7 ivt-l 1-"V1-!d',rr!.rviidu.frd1

sBt nir*:n

3. Prolonged weaning nrrufi,: fifi Set taiture ru e ni,I fi?o'ldrrar weaning > Z riu

6sr'oud d'r set

Saua: og ra,rfifindrrnio.,rdtunreflco{lune$u:n 6noo.rn{rfr1116afirlr:r.rrru5aun: 3t
adrtn:nit nrudr6'q 6a {r-lrunairu:nfiairr:rnrurioufrqo (tCU mortatity 59/o: in-hospiiat mortatity

tzxl rfiurrTl6naornejrl ltcu mortatity 25%) ri'rriunr:nrirrnCo,rtirtyrulofidru'lun1i :cr u

{rJrulddru

Weaning process

rtl€aning "Success" Group 1-3
{exbbBtian & no ventilator
suppo.t ln 2a h. nii'{ Extubation)

Fail SBT or

Subjective indices - Tachypno€s, tachycardb,
- Hy0o/hyperte[sion,
- Agitation or dislress - Hytoxaemia or
- Deprersed menbl shius, - Acir6is,
- obpt|or€sis and
- l Effort

ofr€n relaled to
- cardiovss dJ6function or
- habilily of the .Eltralory pump

aattww-an 1 UfrO\t weanns Drocess

nr:vtir rnia.:tiruvrfl'h rfluretnrcn5#fio,r6nrrrilunrrrir un:rflufi.l6n:J nairrfia uvrnd

d. a.raiXir,i',rnruiun:nr: ::rnf(.dq'nrrlf,rvfAiurriuitrnt:uuntiutu.:drl1 lrrJ:;rfiu{rJruirlniu u".r

!.tdrivfrnirflr'4rh Infdrur.iud. 'rua .::rfiAufi!rrjra t!Ld nfl0'lunltrut d- ',:tfu nr:yfurlytrunrutdrrnilnr:oua

482 rrttirrTni n q ndu5'ru

{r-huorjrrlnd6o rirtcornT:r6u:jru1l0\:{il?u:tuvto.:nt:lldn.:nturar'illdrrri{ilra rj,l?vrflu
drudrdqluoTudulrvrriq:aur:nrfrrfiunr:rdr tnio,:drufiru'lcldadrlfiil::8rinlrl

R',tnHil2n

n'radr.r nrm'rrnau flow no\t T-piece

{r-hu:ruuuo,r urrrifio-:nr: wean d':u t-piece lorululru:dio rapio shallow breathing

index (Fr'vt) {:Jrunralo 1fu2o":i'old tio"l volume :vttltu 500 tJa. l:E tJ:vlrru 1:2 o:do.rrirnr:rflrt
T-piece dru ttow Mr'ln
nq rvi, fii o.s

Step of calculation

1. fiq inspiratory flow rate tu circuit
2. 9"1!?fU flow 1A{ T-Diece

6n inspiratory flow rate lu circuit
nru'lcfl'o rJo tz niosiaurfi uon,:'jr 1 respiratory time = 60/12 = 5 iurfi

dilruv, u'lc t:E lvi'rix 1:2

uao{'ir nr:rrutcr".'rvilnfi g Eiru rflu l+ime 1 dlrl uflv E-time 2 dxu

ohiu ftime 6.,,:riu t/s 1o,,t respiratory time

rda 1 respkatory time wirfi:-r s iurfi d'oriudtld Ftime = 5 x (1/3) iu1fi = 5/3 iu1fi
{ilrunra'llfir ys iurfi ld tidal volume rvhrYl o.s L

fir{rhunruhrdr oo irrfr'ldricat volume rrirfi:.-r 0.5 x 60 / (5/3) = 13 yrn1n

druT ot flow ra\t T-piece

ctnaztuffurfiui

C llu V 'lxtJ = C1Vl + C2V2

(Fio, ro\nyurJ) (flow 1o.,r::uu) = (Fio,o'rn oxygen tank)(flow 1a\t T-piece) + (Fio, l1n
o1fl'rfl room ak) (flow d{:-huo'.:rfirl

ll un1

Fio, flo{iYrr Mrrir o.s
Flow ralrJru MrrYl ta Umln
FiO, q'rn oxygen tank tvirrir.l t.o lrvr:'r:da.:rflu oxygen 100%)

Flow !o\t T-piece rvirrYu X Umin

Fio, q'tfl0'tn'tFl room air tYi1fiu 0.2

now d{:Jrunlrfil rvirnil tB-x L/min

\Feirning liorn Nlechanica|\-enrilaror tli l itzrt'lw[ffii 4Ej

(FiO, flo,J:;uu)(flow nontJUU) = (FiO, t.tn oxygen tankxflow n0{ T_piece) + (FiO, etn

o'rnlfl room ai4 (ftow fi{ilrufirrfiry

=(0.5X18) (1 .oXX) + (0.2)(18-x)
9 = X+3.6 - 0.2X
9-3.6 = x-0.2x
x0.8
= 5.4
x = 5.4/0.8 = 6.75 L

ri,,ttiu da'lrflq ftow ran T-piece adr,,rriau z finr/u1fi

tanfltd1\:6{

'1. Tobin [,4J. Bole and interpretation of weanirg predictors. As presented at the sth Intemational Consensus Conference

in lntensive care lvedicine: we€njng from Mechanic€t ventitation. Hosted by ERs. ATS, ESlcM, sccMand SRLF:
Budapest. April 28-29. 2005.

2. Boles JM, Bion J, connors A, et ar. weaning from mechanical ventiration. Eur Respir J 2007:2g:i038-s6.

:. nriut'a r1r1u:r,l:fr nrrrjr n:::rurrlrlurrrl6d6 Respiratory care in crinicar practrce riuiniri 2 25s3;444-s9.

4 Namen Ai,4' Ely EW Tatter SB. et al. Predictors of successfu I extubation in neuro$urgical patients. Am J Bespir Crit

Care Med 200'1163:658.

5. Rachel L Miller, MD: and Handolph P. Cole Associaton Eetween Reduced Cuff Leak Votume and poGtextubation

Stridor Chest 19961 10:1 035-40.

6 iBastiaan HJ Wittekamp. Clinical review: Post extubation laryngeal edema and extubation failure in critically adult
patients Critical Care 200913:233.

7. Kriner EJ, Shafazand S. Colice GL The eodotracheal tube cuff]eak test as a predicto. for postextubation stridor.

Hespir Care 2005:50:1632 8.

6. Deem S. Limned vatue of the cLff-teak test. Bespir Care 2005:501617-8.
I Laghi F.. lvorales D. Predictors of weaning from mechanical ventilation. Eur Respir Mon 2012:55:169-90.
l0 Carlucci A Richard JC, Wysocki M. Brochard L. Noninvasive versus conventional mechanical ventilation. An

epidemiologic survey. Am J Respir Crit Care Med 2001;163:874,80.

11. Epstein SK, Ciubotaru RL. Independent effec{s ot etiology of failure and time to reintubation on outcom€ for
patients failing extubation. Am J Respir Crit Care Med t gg8i158:489-93.

#4

27

Arterial Blood Gas Analysis and
Clinical Application

nnizuni qfrfiwg

nr:n:roitn:r:riflrttu16ootto,: (arterial blood gas analysis) rflunr:nlrcfirird'ry ttn:
oi riulunr:qun:'nur{rhunrin {alnfildcrnnr:n:rei rn:rvriffrtturfionrto.,tu"uarrr:nrj't'[ riru

'lunr:nuninrir{rhuldtnrs :;nr: triu nr:ufi'ltnmr hypoxemia. nr:ufi'ltnm: hypoventilation

run:nr:ufllanlqato,tn:ooirtfifinrl:nA (acid-base disorders) lvrn, udq:ldrjr rnuofi,tnr:iiru

Itnvnr:rr nnn arterial blood g"" rfioldtun'r:n rrninut{rlru drtfinr:u!nan venous blood

g""'hifinur'lulvrntrrtia,: tissue perfusion

fio# nr::v dnl{rgmtunr:eiruuns trila Hs arteri a I bl ood gas
t. odrtfidruun: u!flird arterial otooo gas 'lfin:ltt1n:h;r6ufr,: oxygenation. ventilation

lrn: acid-base disorder adl€ilutto: tt:Jorua tfiut acid-base disorder Etil{[fiu']
2. Arteriat blood gas lrildrflunr:n:rod'ldtunr:ifiq{i'ultn udrflunr:n:rodrj.rlonn'.1

n'tllrlurr:n (severig ao'r1:nrianm:rfu1
3. nr:druua;urJorta arteriat btood gas o;do,':f{nT:nnionm:ii{rhuriuatirtfi orjrdr

irfiardounii'ilrJqdnuruvvr.:n6fin:l:;noldrttnro oejrld arterial blood gas or"nRu'leinur{tJrtr
Toilrj gdnuu:vnrnfi fi nro'r{ilrurfl uduaro

4. nrreiruunvrnlne{fl arteriat otooo gas }iIfififu nrnr:nri' vurul:nun:nrr:oir,:1
turr,rarqrnrani nr'::inqor unvnr:inurfifizuon':Jnr: lrJfiuuu ni parameter drtl lu arterial

blood oas fittt

Arrerial Blood cas Aralysis and Clinical Application [an?uni AfrrtntS 485

fiafi nnarqurrrJ:cnr#a'leuulficrnnr:dtnr?e arteriat btood gas
1, n'rr'td neparin 'lurJirrrudtrjrru;sl rJ3xrru heparin dldnr:r:riauiiqnuirdrflu}.J

lfiyiadq:aru syringe n1T'lfi heparin dlrnrfiu}Jri,h&ir eaco, nerrr'rn,jrnrr rflucio rdo.rcrn
heparin fillirrzuno.rff'rrnriuaulooon'lrdoirrrn 6rar r:nriacrrn"?odrllfiaolu syringe'lfi nr:
ld n epari n fi'rlo u rfi ulildriti 16 a eo-:l n-? rfl ufl o u

2. Syringe fi1d'tunr:n:ro arteriat blood gas fi Z nlo6a syringe ufi.l [flr syringe

ra1fl6n syringe fln1fl6nil&ufiqrufll:i6uoillfiffrsooninuun;ffrrnriloulooanlrdl.,irurdroon

?'rn syringe {r::urnrnnruuonld drlfi::d'l eaco, n'rn.ir nn' eiru:tolto,l pao, acg\:y;a

n'rn'ir:JnfiriuduorjrT!:vn'!ra.: eao"tun"rotir.,r16on#drn:re.jro,J iosfrn.jroon€lculuu::urnrn

3, ra"'tld6"xsEj1,tt6oorrdr fia.:rir syringe'hJud'lurir u6oyriufirfioosr metabotism no,J[and

leruraylr:'hfi:Jrufifiriorfionutlo',r ln (hyperteukocytosis) r,do,lt'tnrnadrfinrdafismrfi6irdfi

metabol ism qtiiq run4r'fi o.l

+. nr:.lrivlotornrs'1ilru0 drlfi pao. fllni1n?'urfl oi{

rirrJnfilo.r arterial blood gas

eiroir,rl d"ldl, n arteriat btood gas fio{narrrir urirfluririiinl6'loun:.1 s rirryirfu6o

. -rpH. PaCO, Uflc PaO, rvirriu sirurdr Hco"- usu rfl ueirfildlrnnr:n'rurru Iosniurruldcrn

Handelson-Hasselbach eouation n{U

sxnei t pH = 6,1 + log HCO:- ]

our:n16uu'ldrflu 0.03 x Pa.CO,

H- : 24 x PaCO,

HCO3-

6'tfunr:u:.lanrnrir Hco3 aln arteriat btood gas rYuc'oarofiornloldLflo,Je'tnrfluFi16'1ux

lnurovlr:lu respiratory acidosis [ay respiratory atkalosis uucdr'lfrldrir HCO"- ernrfiaosir

(venous HCO.-) lunr:r nrua

drrln6dr,,rr 1o\t arterial btood oas finr:rn:rr rflu.bjn".,,:nr:rrfi t

rsunau'lunr:uilaflo arterial blood gas

t. nr:fiutiu'irrfiu arteriat blood qas ei,rfi?alri

2. n'rtrhttfiu oxygenation
3. nr::J:: lfiu ventilation
4. nr:rl:srfiunrufi orlnfiro.rolqon:ndr': lacid-base disorder)

486 rrtrjrrTninqmfir.rSru
nlrlitd I [fl0{d1lnfirir'r1 no.t arterial blood gas

PaCO, 35-45 . rovr
PaO,
80-100 r.Jr.r.l:o
It--HCO3 22-26 mEq/L
l-r*" *,Oxygen sa'turation 97-100%

nr:Eusu'jrlilu arterial blood gas ei{iltold

fia'iruiu'riunaudd'rnr1 tvi:r;firtrnlritri arterial blood gas nsirr6nriuilfi.l6o fi1tiiu
venous btood gas viafirfiaontrrdrrrnral'lu arterial blood gas ttdrfiwd{fidrfildfin}l

i6 nr:6urTu'jrrflu arterial blood gas ei,rniolri uoncrne:lfier:rurriroir,r1 dtuflunirrJnF

ri',r'iiunnJilunr:rtii z ufir 4".:orefluu-uldlnunltsr:tq't"o pulse oximetry lutu:fiter:n:re
arteriat blood gas 'jrfiri'rlnfir6u':liuvSolri iitfirlilu arterial blood gas e3'tnr:firirtat oxygen
saturation 'lnfitFu.rriu lunriu'lulrtnrr: ttiu nrrctflufiuc1nfll? cyanide, n'l'lY methemo-

globinemia)

lardrr.lnfrro.r venous blood gas finr:l:rl6o Pvo, fidr ::ltru 35-40 tJ . drn:trirl

venous oxygen saturation iouov 70-zs dturir Pvco. q:lrnn'irtu arterial blood gas Ldnflou

rrn:rir pH q:sl"rn'j{u arterial blood gas rfinfiotl

ntnli z ucq.trir nfiro.J venous blood gas t Saltfitllniu arterial brooq gas

ga3

pH 7.35-7.45 7.32-7.42
PaO, 85-100 95-45
PaCOz 35-45 40 50
O, saturation
97 -100% 7O-75Vo

oeir,rl:ffn'rr n1:frn:flluiyusfifi'.:r,rrl.ir nr:d': venous blood gas flur:nri,:lonfit tissue

oxygenation lddnir blood gas tt^lt1v[[tii1 eao, o"tj'lurnrudrJnfi filrilddrjlir tissue
"rt"riat
axygenation fio'roqjturnru{6 niu tunr:frnsuo{ Rivers rrflyn c drrirnr:finurtu{ ru sepsis

r'riolqnriulnlld earty goal directed therapy loutd Scvo. rrnn'jrriotvirrtt zox rflud'rri.':d

'jl tissue oxygenation 6n?o'lri uonornddr pH. Paco."lu venous blood gas finir"lnfi16u,tril

arterial blood gas d'.tliui,Jorold venous blood gas dtr.tfi'lnr:ot:'le orygen saturation 81n

putse oximetry ttvr nltqt'tc arterial blood gas Ifi

Aderial Blood Gas Analysis and Cljnical Applicarion MnSani nfrfrftT 4gj

n,l:il:ltfiu orygenation

r'i6rl:;rfiuld'varui6 udecron.irrfi.ri6frdrlfi,iruuo:cr*rrnrirlfl.filfi e ifi 6o pao.

,A-a gradient rLa: Pao,/Fio,

1. PaO,

eir eaq riurirdldtunr:rl:: rfiu oxygenation louot:,r.ir{rJruo{tunr.tc hypoxemia

r,riolrilouFir Rao, fir*uo{rftlarqta.rfirhu n6irr6afir01q 1n Fbq fio;fiFirn0rn.r rfio.:lrn capittary

membrane fi'ld'lunr:unnur6fluoon6rcuc:lurdrr,rnrsutu{rJrugra.ru riul rnrclnr:ii z

aun.:lfl 2 PaO, ,oo jr+litr1 _]

uonerndd'r eaq u'rdua{nbrJir.rrruaon6rcur'fuhu1df (rractionar inspired oxygen

concentration. Fior) firnr:biooniroulnaajru device tfiooirrl e;lfirir riq fiusrnrir,rniuaonh

o",t uno,:lunr:t.tfi 3

nr:rlfi 3 tcolrdr FRio"- ffiidfirrlte'lrurldirurrdLaial'dlfiaarJtn::nni.iHtfri-oo6riri.rr"r'l

Oxygen cannula 'I o.24
0.28
Oxygen mask 2 0.32
Oxygen mask with bag 0.36
3 0.40
4 0.44 j
5
6 0.40
b 0.50
7 0.60

r) 0.60
7 0.70
0.80
I 0.90
0.99
s
10

orjr'il:ffnrr rir rio, n"':ducnrr'lunrrrrii s riu l.filfirar,n:fitrufifinr:nrrLtErflurr:n6

(normal respiratory pattem) ndr16o a'n:rnr:vrtrlo to-ts n*!dourfi dnrdrurra.ryru'lo r{1rio

nr: rutoaan (r:E = 1:2 - r:e) drfirJrufidn:rnr:nrul,efirfrnird nionr:nrutcnodo.,rtdri'orlrfr

tolar.rrru'lqrdr (inspiratory ftow rate) g.:r8u nrirrfia rlalnr:yrulo rd1 (inspiratory time) dun.r

488 r:mitioinqafiuSru

c:d{lifio.rfin1r6.ro1fl1fl11nn,tsuonr{urnorriuoon6ro!d{rhuld rirtfi no, fi{r]rr'ldirnnnt

et',1 rroo ttud'r o dr^r dol:Jd

rfirarirsii {rJrutruorq 52 fl ldi! nllifila'rj tflu communitv acquired pneumonia tru:d

yrflto go u*ooiaurfi t:E = 1:2ld tidal volume ttrinvnit:J:vr.rrru soo un. orutd4rhuld o*vg"n

cannuta 5 dn:siourfi e.iirurru Fio, d{ilxurluftfii!

tiunaufi ei'ru't inspiratory flow rate dtsiu{:htrmud

flrhunrtrlo so nftriaulfi tlRo.'t'il nr:vrulcllqin;n*,fldrrnrrYird! 60/30 = z iurfi
{rhurrute t:E = 1:2 r!fi6,1'jltrnrlunr:vruleluurin;ai,lrf'trnro g dru uflunr:
vruhrdr 1 dru uac rflutrnr'lunrrvruhoon 2 dru

ft rfu {:-lT uurulo rdlrsin;n*ddr?orrrirri:-r z x (1 /3) lYilri! 2/s iutil

dvga\

LYIUUU 0J9[fr51.]1\tn

{rrron.ulc,tr 2B irll1fi nruhrrrie:n*.ild tidal volume 0.5 An:
{rJrun'ruhrdr oo iurfi nrutt|rdn:ni,ild tio"t volume 0.5/ (2/3) x 60 Anr

= +s dn:dourfi
d'.:riu {:-hunrulcr{rlou'lfi inspiratory flow rate rvirrfi-r +s finrriourfi

$uaaui z drurru Fio, ii4tlra:ruftd:",

aanireudtiJocrn gas flow tfluoanfinuu3qvrf too% ri'lriu{rJruo;fia,:6.tornrrt
crnnrituonfifi Fio, wi'ln-! o.z rdo1fi16 inspiratory flow rate nrrfi{:-lrudo.rnr:

Fio, = 1;ry.n.tryt: g,x1.0)+(iljillj!1llllluron'fifiot1rtllll x 0 2)
inspiratory flow rale
= 15! iL4(4s:5) x 02)

= 5+8

= 0,28

o''rrtu rio, fi{:-tru:ruftdfurvirri! o,za itorfiulfi'jrs't"rn'jr oxygen cannula 5 fiot:
riaurfi {i'rvrnnruhrjn6o;1d Fio. trirri:-r o.+o

nisiir,rfr z {:-l'rumu16rri'tri'rorjr,:d t oior:rld'irnrlinurdeutnrJfrfiructtastfiar:fr vruh ts

n{,rsiourfi l:e = 1:2 ld tidal volume uoin:aiq soo n, u-{n, 6 oxygen cannula s fin:siaurfi
o.:drurru Fio, dft il?u:lufldill

Arterial Bk)od Gas Analysis and Clinical Applicarion nn?uni r]frfrttr 4gg

tvitaau;i nhllru inspiratory ftow rate fitdlu{ftu:rud

rir-hunrutc ts ni.:riaurfi rrflo,r.j,t fl.trmu'louoia:ni.:ftnarrrirriu ootr s = q iurfi
{rJrernraio t:E = 1:2 udn.t.il!ror'lunr:rrutqtuudnvn{.on",lyl.to S riru rflunr:
rrulqrdr t dru ua: rflurrnrlunr:yru'haon e 6iru
a".rrfu {rJrarrutor{rurdarni,rlfirrnrrvi'rrir q x (1/3) lvirryr 4/3 iulfi

rfiuuriqr!6ln:ur.rd

f,rJrunruluir 4/3 iurfi flru'hudn:n*.tld tidat votume 0.s Ant

{rJrunrr'hrdr oo iu'rfi nru'lcrrinvni.ild tio"r votume o,s/ (4/3) x 60 An?

= zz.s Fn:ciourfi

diniu {:-trunru1erfirloul,fi inspiratory ftow rare rvirdl ez.s fin:riourfi

ziunoud o"rurru Fio, ii4rhl:rufldiu

=Fio, 1a"n:rnr:lmnra.0 o?x1.0)+( irJlruornrontulonfifioosr,l r{1 r x 0.2)

inspiratory flow rate

= (5x1.0) + ((22.s-5) x 0.2)

= 5+3.5

22,5

= U,J/

o'lrfu rio, dgrJru:ruf,ldiuuilrYu 0.32 druSuld.irlndr6u,,'iu orysen cannuta 5 fien

dourfi fi.,rnrnrra'lerJnfild Fio, rri-rril o.+o

drrf'.,rnioerirurru'lodru'lmr!c.lr:nrirnuo Ro.ldrnluor-. d,:n'nururnr:firuleroidrirfl

cvllifiilnsianr:r!duurr a,:to*l Rq rtiu16urn-l oxygen cannula, oxygen mask, oxygen mask

with bag Ins T-piece luifidounr{uefruirrnio'rtirervru'lq eiro loulfioonfirquur:.r air-mix d.:

rinrdrhftn'ir{rhuli nq wirril o.+ nr:lfiaanircuu air-mix d:}ur:ld no, hn.rdduog

fii n'n rru: nr:rr ulu a.r {rJr u'lut rurrneu
nrrfl:lolttir eao, orin.lrrnrudrJnfi fiold.jr{:_trufin12: hypoxemia fj,:rflunua;rlrl l6u

lirntr: hypoxia rr:r:{rJrrLfifinrr: hypoxemia ecfinrr: hypoxia drnfiraroraat-:riun.r'r

hypoxemic nypoxia urifiilrufrfinrl: hypoxia qvfinrrv hypoxemia riolrifi"ta rdr tu{il.rufrfi
circulatory (stagnant) hypoxia, anemic hypoxia tlnc cytopathic hypoxia orelrlfinrr: hypoxemia
dlrdru

490 rern-rhr.ininqnfruglr

riiofi rufi'tuttrorolflldRluuan (room air oxygenl rdrll d.rfidr rio, rvirril o zt rfu

f,l lrnrL n!{nlfiirfirhufi hypoxemia 3uttxttfi ut'ln

nr:rci + Ltfi n{nllxJlttrl:.,fl flnnl?t hypoxemia rijofi rutqlobldarnlf, room air

nfl Pltl{ta{ hyporemia 60-80 . l8Yl

Nlild hypoxemia 40-60 rJ .lioYr

Moderate hypoxemia fiosn'ir 40 u.rl:on

Severe hypoxemia
L

otjr.il:firrlrnrr'16rir Pao, tfirtadr,rrfiur'lrior:.rr:nrjril1il:tfiuldd1{l1u:lflfuodlu
nl'r: hypoxemia fi5olri tdu 4il?ultttvfj.l'lsirniomirufirii'lq1nufi'td rio, tilrrYu t.o a?14 arterial

btood gas ru'ir Pao, rvirril zoo lrtt.tJ:or f,rticr:rurnirr1 orl6oird:Jru:rlflrifint"

hypoxemia ud'lunrr tflue?,1rrdr{ilru:rudfi hypoxemia rrn rrfirrta:a{lun1:nt:firrLtq'yu
(respiratory failure) o{1;lfig6lrtriahfluri'r{o PaoJ Fio, o''.lrfunr:t$rir eao, rfia':rir16urtu
n'r:r.J::rfiu'jr{rJraoqjtunrr: lrypoxemia n?o1rjriulfildrarr:{rhuiirruleToutd ,*rn air oxvgen

tll'tuu

2. A-a gradient

Fi'r A-a gradient tfllrunsir.:lor PAO, (partial pressure of alveolar oxygen) uflt PaO,

firrir pno. qcfiFir lnn'ir Pao, LdxJa A-a gradient = PAOz - PaOz

t Jv"u:

Pulmonary capillary

Sitr:*:i::: Erythrocyte

PP.AAOc" 62 coz Plasma

A, A-a gradient =
PAO"-PaOt
lnleratitlum

flli t uaalmnx#urtuisznit t PAo,, Pao, uaz A-a gndient

Afterial Blood Gas Anall-sis and Clinical Appljcati()n nn?uni nfrftBtg 491

lrir n6ror A-a gradientletu nFqshirfiu 20 . ?a uoifirfioruilrnd'u Fi1 A-a gradient

fic:fiFirurnduorrilildru rfiamrn interstitiat capi ary membrane yurd-? rnnsu n-tnrnr:fi 4

' gxrnfr 4 rfA-a sradient = z.s + (orqrfluf,

6i,:fido.rrfrurruyrrfiotfil{eir A-a gradient 6onr:r{rurnryr eno, fi.le vfirdr u:.J: r.r'unu
Fio, ua: paCo, d.:our:na"rurruldnualnr:fi s

axnnfi 5 pAo, = (Fio,x 713) - (pacq / R)

Teud zte rflun'rdldcrnnrrrJniu 1 !:rurnro {r atm) fi,rfirirrrirnil z6o ru.:J:avr
ora o ndrunrun'urirfi t u::urnrq6r rvir nTu +z :.rr.:J:ovr

n rflurirnrd lcin RQ (respiratory quotieni) d.:r{rurru'ldcrn carbondioxide

production/ oxygen consumption lourJn6fidlrirrY! o.a udduorjri::dnuru;lo,roryr:ii

rfiilruli'fu lnudnrilulsrn:oifi no lilrfii 1.0 Tilrdulfi Re rillni! o.e Lrn:bil'u'lfi no

rrirn'u o.z

'lunr:ntrurru n-a graoient lnal'rlil#u fi1i.fi Fio, fiounjr o.o rir R firirryirril o.a

, rflyfirld rio, rrnn'jryiarvilriu 0.6 ri1 R fidldrrilr 1.0

I

oioriuocrfiu'jrrir A-a gradtent qsfirir:r1nyiofiouduoqjfi'l Ro" ua; paCO? n-.rlit-tfil Fio,

lrndu rir A-a gradient fiorrrnr*uo.lu1,J,{ru d:,rriurh:Jnhm.l A-a lraoient ,'.,run.rrd s ,f,

'ldldlarr:nr:yT ulelrruts room air oxygen rvirriu

iinlu':ru A-a gradient oril{t1o[5x oru:nrirldlouqernaro:'ll.llo.rrir paq rlay paco,

irtiafln'jr t t o rl. :oyrn?olr.i rrnruo:rlrorra'1 pao, ttfly paCo, riarn.jr 1 1o tr.l5oy] rLfifi.t

'jrtflu wioe A-a gradient d r.oor

",r.

rl::lugfta.ln'r:1S A-a gradient rfu our:ndur'lflunr:l:srfiufirdrryonB,JR'r't! hypo-

xemia un;riur'ldfinonrrh;fiyr6ntrr1unr:unnr filuffrroonirou'luiao"ld Inuflrl{ Fio, n.:fi
ri1 A-a gradient fig.:duuoa,r'jrrurBRntmar:Jon:uu:,r un:eir A-a gradient dfiounr lno,:ir

vr ur ionl'HJo.,t:l a o 618u

riialu{:-l': u hypoxemia fi uurnr.,rrJ$:ihlunr:yrolvnd.r rr unfi d t

t1 l1l41,O{fn?s hypoxemia

1. Decrease Fiq fiilrufi{nddfiL riO, fioun.: ru1dlu{,r-htddrdnniu}'l lsmore

inhalation injury)

2. Cenlralt neuromuscular hypoventilation rfio{rhufinrr: hypoventitation ovni'lfi
PaCO, Fr'.r arlrrnurj.,r hypoventilation oon'ldrflu 2 tl?;Lnfl 6o central/ neuromuscular

492 rerni'rrioinqnduS'll

Normal A-a gradieni {Fio, o.2) wide A-a gradient (Fio, o.2)
near normal Tao2lFioz Groz>o.2) Low PaO, /FiO, (FiOr>O.2)

U*rrfi Fi0, central / neuromuscular

hypoventilation

Ui!rfi minute ventilation

(rfilr tidal volume, rdr RR)

. PEEP uffLunrr; low

.Inverse ratto o, delivery /

ventilation h igh oxygen
a Prone
consumption

Dead space
{eg, pulmonary

embolism / severe
pulmonary artery

)

-Thrombolytics /

anticoagulant
-Pulmonary vasodilator

tuwgOi uaauwznrlJfitffitf,on.,srnn'lun'tzr hypoxemia

luhypoventilation dtfi A-a gradient:Jnfi tdtn{dhJlrifirurif,n'l aa LLflt alveolar hypoventilation

ii,rfi n-a gradient l'rnn'i'rdn6 d,tn{rdc:fiuurinnlvitu oqfilrru?,r

3. v/Q mismatch v 'lu6,l ventilation un: perfusion lrittlr:fl1 dtnT: hypoxemia d

rfiorlrnorrmqdo:oar.rcuardanr:'1fi 1007o oxlgen t'iiu pneumonia dfirurianrtlrjlrnrin
tun{ldfiuci perfusion trtibifi ventilation r-i{fi':'jrfiilurionrvl'luq.lnrfi1urr:tlrn d,l

,r'l'ls hypoxemia firfioorncttqdlv'lriotottsuo,tsionrr'hi 100% oxygen c;dolufihlqunrltd
PPEP (positive end expiratory pressure) violdnr:rjrunlutqii6u rdu IRV (inverse ratio

ventilation) nr:uoun'ir (prone position)

Anerial Blood Gas Anal-vsis and Clinical .A.pplication nn?uni gfiftttJy 493

iun{#tifi pe.tusion fi ud ventitaiion ri.ruanfi,0'jr urionrvrrfioduii putmonary vessets

miu lu$Jru putmonary embotism nrirdo:oroucuo.,roi0nr:r$i Fio, rir.,r usilslrjnolouarsio
n1ild PEEP da.rinurlounr:urior rlq niu nrr'tfi anticoagutant xio thrombolytics

4. Shunt tflrr V/Q mismatch grJrrutru',:frfiuoi perlusion rreilrifi ventitation fi z :J:crnyl
1) Intrapulmonary shunt rflunarion'rvrfrolntdfinr:n:so1unal U16dn'lilri.rd0{

dru :-j,:ronfi,rrurinnrvrluo.rolfiluut{rJln n'nrfjx Fio, c;lrif i 'rrnufil:rnrr:

hypoxemia ld dorufilndrunrr'lt pEEp fiion'lrinu{ouiidu rtiu tRV (inverse
ratio ventilation) ria prone position
2) Extrapulmonary shunt tflu urianr uonq{n rdu cyanotic heart disease.

putmonary AV fistuta d,lda.rufi'lnl:nir'rfrunrrrqMrriu nr:rfir Ro,nionr:'ld eree
'hior!'r:nufi1$ snunt miofld

5. Diftusion defect uiunejrfifi perfusion r!fl! ventilation :Jn6 neirrfio lrihi V/Q mis-

z,match ttdnt'utfiotU:nfioqjfi alveolar capillary membrane !'riu pulmonary fibrosis, interstitial

lung disease nai fio;norouo,rdon'urfir Ftor:ir,l udlrinalnuoroianrrld peep

6. Low SvO2 nr.l1afi.t venous saturation urtr f,rm:otfiurfioon'rd,,rs:?oldcln central
vein Q'ln superior vena cava (q'tnfllu central line r;ocru cut down) ioqln pulmonary artery
{elndlu pulmonary artery catheter. distal port) iilnr:d u"nous saturation oirfiolnqd],rd

1) Oxygen delivery nat d.:fiorrtqldorn cardiac output nrt (hypovolemic shock

cardiogenic shock, obstructive shock), nrrlin lanemia) [0tn1?: arterial

hypoxemia

2) lssue consumpiion 4..rzru nr.nufi,rnr#rdordadrurJnru (peripherat tissue) 'ld
aonirqurrn niu nrr:ldg.r. oiu lshiveringl, d'n

n'rori,cii e {:Jrrrrro,q so fl filfilri lo firorwlnuru z-g iu niar:rfiarnr:urusreiouu:,rf'r

n"r n:'rtdr',,:nrunl motor power grade 3+ all, deep tendon reflexes 1+ all extremities ufly

glove and slocking decrease pinprick sensation all extremities {r-lrrrrah tZ ni{siourfi loEJ

ld roor air oxygen nt?e arterial blood gas vryjr pH 7.28, Paco2 55 u. :oyr, Paor 65

url.:.har, Hcos 27 meqa- lfiruJnnrn arteriat blood gas 'tu:J:srffuro,r oxygenation

{rhaa{lunrr: mitd hypoxemia rfiomrn eaq agl ?hn G0-s0 rt . ro1,r

fior:ruryrcrrtqror hypoxemia lu:rudot r:nlfi A-a gradient ldrfio,:crnfi rutrutr
fitu room air oxygen

=PAo,nhurru (Fio? x 213) - (paco, / R)

= (0.2 x 713) - (s5 / 0.8)

494 rrtdrtTninqndugru

rdatorn Fio, fildrioun'i'r 0.6 ei, R 6.rrvirrTrl o.a

142.6-68.75

73.85:r.:hoYl

a"lurru A-a gradient = PAO, - PaO,
73.85 - 65

8.85 lttJ,U:olr

ic:lfiuld'hrir A-a gradient rln6 (d.rei, n-a gradient nfitufl]q 30 = 2.5 + (30/4) = 10

tJtJ,lJ:0Yl)

rfiofior:rurRT ntqta.r{rhu:ruua {rJrulrrlurrr''rvrtidrudnuru:flr.tnfifinsa,t acute poly-

neuropathy 6.:r{rlfirir cuittian-Barre syndrome dtdrtfiinfirrlrdotunr:nrutcEiouLL:.l'ld d'rfu
fl'rrflqfla{ hypoxemia 'lu{:hu:rud6.':a6uruldoln neuromuscular hypoventilation

'luyrr,,lnaun"ufirr{T urrurir A-a gradient ldrrnn'itlnfi viodr Pao2/Fio, drn'jr:Jn6tu

{r1'ran{l neuromuscutar disease dotFnn.o'jrfirrLrionufi:Joodudra dvuldrjoul ldrrri :.loo

uvfu latelecrasis) tto: ano-nrdu (pneumonia) ernnr:drn'n rf,o,rlrnT:nlunsjldo:fiorario butoa,

muscle

d'rod,rd + {ilrurruorq +s fl d:lq:rrflufive'r 'rv,,ruLrvirti6rua'rnr:1d 1o nolrruru 4 iu

dourrl:.,rnurrra nmdr.rnruvu'jr{rhu ru'lq ze ni.ltiourfi rflii'lo .oom air oxygen fi,,,:tfia.,,:

rjoovruirfirdut bronchial breath sound tLnY fine crepitation firlaonduudrul'lr lfilirnr:n:re

arterial blood gas l,ryjr pH 7.50, PaCO.25 r.D.:. :al, PaO. Z0 N.rilafl, HCO3- 19 o,,ttt:Jnrua

arterial blood gas lu :;l6ulo'l oxygenation

{rJruag'tunrr: mild hypoxemia rfiooarn Pao, a{ludrr 60-80 tJtr.:hofl
rilr:rurrrorwqoo.r hypoxemia tu:radarrr:o'ld A-a gradient 16tfjo,rrrn{rJrtl,trulo

dilu room air oxygen

rirurru PAo. = (FiO, x 713) - (PaCO, / R)
= (0.2 x 713) - (2s / 0.8)

rdomrn Fio, dldriaun'jr 0.6 ri. R 6.rMrrTr o.a

= 142.6-31.25
= 1 11.35 tJ .UloYl

fi1l.t?nr A-a gradient = PAo, - Pao,

= tt t_Jc - /u

= 41.35 l.rrJ. ror

Anerial Rlood cas . ,nal-ysis and Clinical Applicarion toniunf nfifrMS 495

rrrfiu'ld'jlFi1 A-a gradient n{r*rn'j1J:n6 (rir:Jnfiza,,r A-a gradient iiarq +s fl = z-s *
(45/4) = 13.75 lJtr.t:'r)

rfiafilr:rurorrt4fla.lfuhu:'tud firJru r u!!flytrid?un'num:r1nn6finro,J community

acquired pneumonia fl'rt14st?,o,t hypoxemia rirqvlfiacrn V/Q mismatch rJtnfif,u

3' PaO"/FiO,

at eaotrrto, rlnfifirirryirnil soo nhurruldornnuilndnrutcld Fio, rirrfi 0.2 fid'r

Pao, rlnfir 'rfi'rr 100 rrrt. toyt h'1 pao"/Fio, uiunirfifirl:;lmrilunr: :yrfiunrrv hypoxemia

rdo{ernnr r:nldltirfiu hypoxemia ldrfiatdrir Fio, ei.r,r"l riu driurfiourYrnr:ld eao. rio

A-a gradient fiorilr:n'ld1firaln:fi rio. o.z rrirrful eir pao,/Fio, firiouuon.:fi,rrur6ontrtu

rloo ttioynonrfioottu:Joo (putmonary vascutar tesion) 1oufil pao1Fio, frfioun'jr 200lu difiuse

alveolar lesion rrflno'ir{:Jruodlun't1y severe shunt d,rnrr: hypoxemia cylrjfio:Jouo.rnau

fl!o\:ri0n1rid FiO, t .o do{fiqr:mnrrls ppe p nio inverse ratio ventitation'lunr:ufih hypoxemia

inmurdr'lofifin'j :rat pao,lFio, n'riarn'ir goo uan.r'jrfi rurflu ARDS lacute

6lrespiratory distress syndrome) Berlin definition ro,: nnos rdo.lerndr PaOlFiO, fifioun'j1

rat{irtsoo fulil'ldLtcn,Jfi{ volume status rvr:r:'irfir-haiirflu congestive heart taiture !uu,:\:

fiarrr:nrirlfipir paolFio2 rioun'jr goo ld'niutdu?du udrflun:nisar votume drfiu uri nnos

tiun:niso.t volume lng

nr:'ldrir eaoyRo, orm:orjurtdlunr:rJ:"rrir Fio? dfiil'tuda,in1:'ldnuornrrri'.rd

sxntzfi o (PaO1FiO,) j = (PaOI FiO..),

n'eorirdi s {:Jru:runfl.:.ldfunrrifirdarflu ARDS TJrurdlfirnia.:delnru'hlndd Fio, wirril

1.0 Jd Pao, Lyilriu 100 l.u.r. :or fio,rnr: frJ Fio, ifildri1 oxygen saturation MrrY! go% q;

fia.:'ld rio" rrirlsr

ruitcrnnrr ffrJl'rYudnr hemoglobin oxygen dissociation curve (ra''.1*oat'lu?rlfi z)

oxygen saturation 90% oynr.Jrilfi1 PaOr 60 x. :flvr

ernnrr f, fiuf (pao,/Fio,), = (pao"/Fio"),
,0.100/1
= 60/FiO,

FiO, = 0.6

o"-rfuitnr:rlir rio, rrirni:.r o.o lfjotrild oxygen saturation ryirrY! sox

d nlr (PaOlFio ,11 = (PaO"/FiO!, fidanr:::i.':'lunrdd6a lunur6anrnso.r:loofifi

nr:l:JdEJuu n,torjr.rrrorfr ldu congestive heart faiture dmalauorn'anr:inurfiruurrTliof,rr: