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Debriefing and follow up

Make sure that a consultant visits the mother. Minor injuries are
common. Serious but rare morbidity includes trauma or perforation to
the larynx, pharynx, or oesophagus. Perforation, presenting with pyrexia,
retrosternal pain, and surgical emphysema, is associated with a high
mortality; if suspected, refer for urgent review by the ENT surgeons.
Awareness during anaesthesia is more frequent if intubation has been
difficult: enquire directly about this.
Make full documentation about the ease of mask ventilation, grade of
laryngoscopy, airway equipment or adjuncts used, complications and
other relevant information, and offer the mother a follow-up outpatient
appointment with an anaesthetist. Complete a clinical adverse event
form for each case.
You can download an airway alert form from www.das.uk.com. When
completed, send one copy to the mother’s records, one to the mother
and one to the GP. Ensure that an airway alert is added to CRRS, e.g., as
an ad hoc note.

25. Kinsella SM, Winton AL, Mushambi MC, Ramaswamy K, Swales H, Quinn AC,
Popat M. Failed tracheal intubation during obstetric general anaesthesia: a
literature review. Int J Obstet Anesth 2015 Nov;24(4):356-74.

26. Odor PM, Bampoe S, Moonesinghe SR, Andrade J, Pandit JJ, Lucas DN, Pan-
London Perioperative Audit and Research Network (PLAN), for the DREAMY
Investigators Group. General anaesthetic and airway management practice
for obstetric surgery in England: a prospective, multicentre observational
study. Anaesthesia 2021 Apr;76(4):460-71.

27. MBRRACE-UK. Saving Lives, Improving Mothers’ Care: Lessons learned to
inform maternity care from the UK and Ireland Confidential Enquiries into
Maternal Deaths and Morbidity 2013–15. Oxford: MBRRACE, December 2017,
page 67.

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Failed or difficult intubation

28. Cook T, Woodall N, Frerk C. Major complications of airway management in
the United Kingdom. 4th National Audit Project of the Royal College of
Anaesthetists and the Difficult Airway Society, 2011; page 185.

29. Rucklidge MWM, Yentis SM. Obstetric difficult airway guidelines – decision-
making in critical situations. Anaesthesia 2015; 70:1221-9.

30. Mushambi MC, Kinsella SM, Popat M, Swales H, Ramaswamy KK, Winton AL,
Quinn AC. Obstetric Anaesthetists Association and Difficult Airway Society
guidelines for the management of difficult and failed tracheal intubation in
obstetrics. Anaesthesia 2015; 70:1286-306

31. Ashraf-Kashani N, Kumar R. High-flow nasal oxygen therapy. BJA Education
2016; 17(2):57-62.

32. Shippam W, Preston R, Douglas J, Taylor J, Albert A, Chau A. High-flow nasal
oxygen vs. standard flow-rate facemask pre-oxygenation in pregnant patients:
a randomised physiological study. Anaesthesia 2019; 74:450-6

33. National Institute for Health and Care Excellence. Caesarean birth: NG192.
London: NICE, 31 March 2021; section 1.4.20.

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Obstetric haemorrhage

[Revised October 2018 with Dr Alastair Fairfield.]

Chapter contents 101
102
APH (antepartum haemorrhage) 103
PPH (postpartum haemorrhage) 109
DCR (damage control resuscitation) 115
Managing haemorrhage cases 118
Pharmacological treatment of uterine atony 121
Use of red blood cells 124
Use of haemostatic blood components 127
Use of systemic haemostatic agents 128
Mothers who refuse blood transfusion
Balloon occlusion catheters and fluoroscopy procedures

Obstetric haemorrhage is a common occurrence and can occur suddenly
at any time.

For active management with checklist® M-QRH

Major haemorrhage is defined as a haemorrhage more than 15% of
circulating volume: typically, 1000 mL using an estimated blood volume
at term of 100 mL kg-1. It will be 750 mL with a booking body mass of 50
kg. Massive obstetric haemorrhage (MOH) is usually defined as blood
loss in excess of 1500 mL in pregnancy, labour, or following delivery, or

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continuing loss in excess of 150 mL min-1. This may be appropriately
lower in mothers with a low booking body mass.

• The median blood loss at caesarean birth is about 500 mL.
Sometimes it can rapidly transform into massive haemorrhage.

• Tachycardia, hypotension, and vasoconstriction represent severe
maternal hypovolaemia.

• Coagulopathy may cause haemorrhage. Haemorrhage causes
coagulopathy.

Roughly 1 in every 10 mothers undergoing operative procedures will have
a massive obstetric haemorrhage. It is rare in planned caesarean birth
without a specific risk factor, such as abnormal invasive placentation or
low anterior wall fibroids. It is sometimes seen in intrapartum caesarean
birth, especially in induced or prolonged labours, but massive obstetric
haemorrhage is much more likely to occur in operations for examination
under anaesthesia, perineal repair, and manual removal of placenta.

The successful management of haemorrhage includes obstetric
management specific to the cause of the haemorrhage – usually delivery
for antepartum haemorrhage and uterine contraction or surgical repair
for postpartum haemorrhage.

A continuing massive haemorrhage threatens life: you must send for
help. Do not attempt to manage it on your own.

Consultant attendance

The authors of the maternal mortality reports made an unambiguous
recommendation [34]:

“If haemorrhage occurs, experienced consultant obstetric and
anaesthetic staff must attend.”

Massive obstetric haemorrhage call – MOH

With blood loss more than 1500 mL and continuing or continuing more
than 150 mL min-1, you must activate the MOH call [35]. With bleeding in
the 1500-2000 mL range, and well controlled, the MOH call may be stood
down swiftly.

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Call 2222 and state ‘massive obstetric haemorrhage at ….’.

This will ensure that blood bank staff are aware of the need for assistance
and portering staff will attend the operating theatre. Make sure to call
blood bank immediately so that the blood bank technician has the
mother’s identity details and specific clinical needs; they may be able to
send group-specific blood (if the mother has recent previous history in
this hospital) quickly instead of using the O Rh D negative units. The
porter will first come to the clinical area and then can be directed to pick
up emergency blood (from satellite fridge or blood bank) and take the
blood samples up to the blood bank as appropriate.

Although several bleeps in the theatre will sound with the MOH call,
make sure that everyone present understands the current clinical
situation. Reassure the mother if she is conscious.

Remember to call 2222 and stand down the MOH call once the clinical
situation is stable, and to make sure that the massive haemorrhage
proforma has been completed.

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The lethal triad

The initial insult is massive haemorrhage, which causes physiological and
biochemical derangement. Each component of hypothermia,
coagulopathy and acidosis will both worsen and be exacerbated by the
others. Delay in restoration of circulating volume may result in tissue
hypoperfusion, organ failure and disseminated intravascular
coagulopathy [36]. As obstetric haemorrhage becomes massive
haemorrhage, understanding this triad is the key to being able to prevent
its development.

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APH (antepartum haemorrhage)

APH is bleeding from or into the genital tract between 24 weeks and
birth. The most important causes of significant haemorrhage that you
may see are:
• Placenta praevia – see page 391.
• Placental abruption – see below.

For active management with checklist® M-QRH

Placental abruption

Clinical features of major placental abruption are:

• Abdominal pain and a tense, tender uterus.

• Shock.

• Vaginal bleeding in low proportion to the degree of shock.

• Fetal distress or death.

Coagulation disorders are more common in this condition. You should
request fibrinogen specifically on the coagulation screen, and order 4 RBC
and 4 FFP immediately on making the diagnosis of placental abruption.
Do not wait for haematological evidence of coagulopathy. In damage
control resuscitation, suspected disseminated intravascular
coagulopathy, placental abruption and intrauterine death are indications
for transfusing red cells 1:1 with FFP. Discuss with the on-call
haematologist whether cryoprecipitate would be a better choice. Aim to
keep the fibrinogen level ≥ 2 g L-1. Levels less than this are strongly
predictive of worsened postpartum haemorrhage (see page 123).

DIC or disseminated intravascular coagulopathy can occur in major
abruption and initial coagulation studies must be repeated at least hourly
during the massive transfusion phase. TEG is available in cardiothoracic

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critical care and can be used to guide transfusion; we aim to install a TEG
machine in obstetric theatres soon. Platelet transfusion may be required.
Avoid tranexamic acid in DIC; seek haematological advice if it appears to
be indicated.

PPH (postpartum haemorrhage)

Primary PPH is the loss of 500 mL or more of blood from the genital tract
within 24 hours after birth. Secondary PPH is abnormal or excessive
bleeding from the birth canal between 24 hours and 12 weeks
postnatally.

For active management with checklist® M-QRH

Unexplained tachycardia during caesarean birth, even when the mother
is awake with a reasonable blood pressure, is an ominous sign that you
must act upon. Check whether she could be bleeding, and then check
again. During any caesarean birth, observe the bleeding and query the
uterine tone. Establish basic measures including uterotonics and
tranexamic acid (see page 106).

The most common cause of primary PPH is uterine atony. The
obstetricians use the ‘four Ts’ mnemonic – Tone, Trauma, Tissue and
Thrombin.

Cause Incidence

Tone: uterine atony. 70%

Trauma e.g., cervical or vaginal tears, ruptured uterus, 20%
extension of uterine angles at caesarean birth.

Retained tissue e.g., placenta, membranes. 10%

Coagulopathy – often a late cause. 1%

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Remember the effect of Temperature – hypothermia is an exacerbating
factor.

There are also risk factors that you cannot control at the time, such as
having chorioamnionitis, multiple pregnancy, abnormal placentation, and
gestational age at delivery. The incidence of primary PPH is higher if the
woman is 41-42 weeks pregnant at delivery [37].

Examination under general anaesthesia is indicated by:

• Failure of uterine contraction with obstetrical methods.

• Persistent bleeding with uterine contraction.

Owing to its indications, EUA (examination under anaesthesia) is typically
associated with heavier blood loss than any other obstetric procedure.
Consider calling for help. Consider use of damage control resuscitation
principles – see page 103.

Consider critical care for the postoperative management of mothers who
have had hysterectomy performed to control haemorrhage. However,
this is not always indicated. With prompt and effective prevention of
shock (maintenance of arterial pH due to good resuscitation) mothers
who have had haemorrhages more than ten litres can be managed on the
labour ward in enhanced maternal care – but be careful to consult with
the labour ward coordinator as to whether the midwives have the
capacity to provide this at the time.

DCR (damage control resuscitation)

There is no single evidence-based management protocol for fluid
resuscitation in obstetric haemorrhage [38], but much attention has
recently been paid to studies of resuscitation for massive haemorrhage in
military and trauma anaesthesia. Improved survival has been attributed
to the practice of damage control resuscitation (DCR). Early recognition
and effective action prevent shock and its consequences.

Haemorrhage is a highly dynamic situation. In all cases of obstetric
haemorrhage, a key decision is whether the bleeding can be managed
with salvaged red cells alone, or if a massive haemorrhage will exceed the

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capability of a treatment strategy based on salvaged red cells. In this case
you should initiate DCR and acquire additional allogeneic blood products.

This decision is dependent on balancing several factors:

• The rapidity of the bleeding.

• The total blood loss.

• The efficiency of collection and processing salvaged red cells.

• The mother’s pre-existing condition, body mass and haemoglobin
concentration.

• Her physiological and biochemical response to the haemorrhage.

In this, the situation is not quite the same as that pertaining to the
military or polytrauma experience, where the initial injury is explicit and
severe, and DCR is initiated immediately on presentation.

DCR is an approach to devastating haemorrhage developed for the
management of trauma patients, but the principles can readily be applied
to massive obstetric haemorrhage. The principal aim is to mitigate the
lethal triad of hypothermia, coagulopathy and acidosis that arises from
massive haemorrhage. DCR is characterised by early blood product
administration, haemorrhage arrest and restoration of blood volume
aiming to rapidly restore physiological stability [39].

The infusion of large volumes of crystalloid is not appropriate (volumes
over about 2 litres of crystalloid); instead, the aim is to avoid dilution and
coagulopathy by replacing lost blood. While the inspiration for this came
from the military and trauma experience, it is increasingly recognised that
DCR is appropriate in other massive haemorrhages. The 2016 AAGBI
guideline on use of blood components states [52]:

“During major haemorrhage due to trauma and obstetrics, consideration
should be given to transfusing red cells and FFP in preference to other
intravenous fluid.”

Accordingly, the recommended strategy to manage massive obstetric
haemorrhage is to keep under constant review the point at which ABG
evidence of haemorrhagic shock prompts the move beyond use of

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crystalloid and a small number of red cell units towards the full
application of damage control resuscitation.
The main components of DCR include:

• Permissive hypotension, avoidance of routine vasopressors and
restrictive crystalloid administration.

• Use of balanced transfusions.

• Haemostatic resuscitation and tranexamic acid.

• Rewarming.

• Correction of acidosis by transfusion.

• Arrest of haemorrhage by surgical and non-surgical techniques.

• Maintenance of normocalcaemia.
Keep awareness of the situation – mothers can be seriously harmed by
over-replacement as well as under-replacement [40]. Record the fluid
balance regularly throughout the resuscitation process (including the
current urinary output and current estimated blood loss).

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Anaesthetic actions to take to achieve damage control resuscitation

This summary is an aide-memoire for active management and should be
read with the significant details on the subsequent pages.

Declare Massive Obstetric Haemorrhage – 2222

Request additional and senior staff to attend.
Assign one midwife as scribe with the MOH-CPR form.
Call blood bank 25398 (#2169) – give details and make requests.
Protect the mother
Prevent aortocaval compression if still pregnant.
Beware of cardiovascular collapse in GA. Use propofol in reduced
dose, or better use ketamine 0.5-1 mg kg-1.
Correct acidosis with transfusion
Restore blood volume and oxygen-carrying capacity to correct pH,
lactate, and base excess. Use red cell salvage if possible and warmed
allogeneic transfusion through rapid infuser as indicated.
Arms out for access.
Insert arterial line; send ABG every 30 minutes.
Large-bore IVs and consider Vascath; use the Belmont rapid infuser.
Hourly bloods: FBC, U&E, coagulation screen and fibrinogen levels.
Limit crystalloids and vasopressors.
Keep continual awareness: blood loss, fluids given, and urine output.
Maintain uterine tone
Oxytocin: cautious use if unstable cardiovascular status. Reduce or do
not use bolus. Increase infusion rate to 25 mL h-1 (20 units in 50 mL).
Ergometrine: 50-100 mcg by IV injection repeated as necessary.
Carboprost: 250 mcg IM repeated up to 8 doses.
Misoprostol: offer 1000 mcg at end of case.
Volatile agent: limit ET isoflurane to 0.8%; consider propofol TIVA.

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Ensure early haemorrhage control
Liaise with obstetricians and midwives: is senior help needed for
surgical haemostasis with brace suture, haemostatic square sutures,
internal iliac ligation, or hysterectomy?
Inflate internal iliac balloons if in place.
Administer tranexamic acid
Load 1 g over 10 minutes; maintenance 1 g over one hour.
Maintain normocalcaemia with calcium chloride
Use ABG as the prime guide.
Maintain ionised Ca2+ > 1 mmol L-1 with calcium chloride 10 mL slowly.
Minimum is 10 mL slowly per 4 units PRC or salvaged equivalent.
Maintain normothermia
Check the core temperature.
Use the forced air warmer if the warming mattress is not sufficient.
Keep on top of basic actions
Check the volatile dose again – isoflurane 0.8% end-tidal, with N2O.
Check uterotonic usage again.
Prevent and treat coagulopathy
After first box of 4 PRC, use a guide ratio of 4:2:1 PRC:FFP:platelets,
with cryoprecipitate as needed.
Check regularly against lab results to achieve aims:
Keep platelet count above 50 x 109 L-1 (transfuse at 75).
Keep fibrinogen level above 2 g L-1 with cryoprecipitate.
Review the mother
Keep records up to date – Obstetrics Perioperative Pathway &
MOH-CPR form.
Review blood results. How is the base excess and lactate? Is there
continued bleeding? Does she still need DCR?

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Decision making in massive haemorrhage
Review the mother’s status continually to determine whether she is
improving, or whether damage control resuscitation should be initiated.

MOH: review patient

Successful management Patient not improving;
with cell salvage; management needs exceed

processing quickly and cell salvage alone
keeping up with losses

Patient not Call blood bank if not already done so,
improving check patient status and give further
information; make appropriate orders

Order MOH pack or Use O Rh Neg
(4 RBC + flyers; not if red
cell antibodies
appropriate other than PD
other products)

Review Apply treatment; establish resuscitation
again priorities and commence damage

control resuscitation; arterial line and
regular samples; use Belmont rapid
infuser with blood and FFP; monitor
therapy by improvement in base excess
and lactate; regular fibrinogen tests

Patient improving; continue with regular review

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Managing haemorrhage cases

Conversion to general anaesthesia

If the mother has a neuraxial anaesthetic in operation when massive
haemorrhage supervenes, particularly with the activation of damage
control resuscitation, then general anaesthesia may be indicated. This is a
difficult decision that should not be done as a reflex response to massive
haemorrhage, but like any technique, for its indications. These are:

• Protection of the airway.

• Control of arterial blood gases through mechanical ventilation –
improving acidosis and oxygenation.

• Management of severe distress.

• Management of pain in prolonged surgery.

Emergency peripartum hysterectomy does not necessarily mandate
conversion to general anaesthesia if the above indications are not met.
Moreover, this is a high-risk operation due to the pregnancy itself: the
enlargement and hugely increased vascularity in the area and the
distorted anatomical relationships between pelvic and abdominal organs.
The surgeons will remind you that an emergency peripartum
hysterectomy risks its own haemodynamic instability, due to the
technical difficulty of undertaking the surgery. It is important to
endeavour to achieve control of the resuscitation before proceeding to
dissect, clamp and cut enlarged, tortuous and adherent vessels supplying
the haemorrhaging area.

However, if nothing else surgery is likely to become extensive and of long
duration and the mother overly anxious, restless, and uncomfortable. A
good practical course of action is to discuss with the surgeons gaining
control of the haemorrhage, doing a planned conversion to GA, and then
proceeding to complete the operation. Form your plan with the
anaesthetists who have arrived to help and make sure that a consultant is
in attendance.

Discussion of conversion to general anaesthesia is on page 377. In
massive haemorrhage, the surgeons will be reluctant to step back and so

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establishing a safe induction area will be difficult, and to add to the
physiological instability of pre-existing anaesthesia, the mother is actively
haemorrhaging. There is a significant chance that conversion to general
anaesthesia will be indicated during a damage control resuscitation
procedure.

Choosing the right moment is always challenging.

• The risk of failed intubation is significantly increased. Have
another anaesthetist in attendance and a backup plan.

• Put the arterial line in first and take ABG if possible.

• Communicate with the surgical team to indicate plans and establish
your space.

Where hypovolaemic shock is severe, few if any drugs may be required.
In the case of a conscious mother with severe ongoing haemorrhage, use
ketamine 0.5-1 mg kg-1.

Maintaining records

This is essential but can be forgotten, or taken as low priority, as the
clinical work proceeds. Use the MOH-CPR (Checklist, Prompt & Record)
forms available in labour ward theatres. This form will also prompt
appropriate actions in massive haemorrhage. Keep in close touch with
the midwife who will have been allocated to act as the scribe.

Complications of resuscitation

Iatrogenic complications of vigorous resuscitation are important, and you
should be alert for them.

• Hyperkalaemia. Detect this on the regular ABG. If K+>6.5 mmol L-1,
stabilise the myocardium by checking that calcium has been given,
and then shift potassium into the intracellular fluid compartment
with 10 units insulin in 50 mL 50% dextrose into a large vein over 30
minutes. An alternative is 10-20 mg salbutamol nebulised into the
ventilator tubing. [41]

• Hypocalcaemia: detect on ABG and give calcium as in DCR.

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• Pulmonary oedema, occurring because of over-vigorous fluid
therapy, or when associated with transfusion related acute lung
injury (TRALI).

• Dilutional coagulopathy, occurring because of giving imbalanced or
over-vigorous fluid therapy with insufficient blood components.
Send coagulation samples at maximum intervals of one hour. TEG
(thromboelastography) is available in cardiothoracic critical care.

Blood component transfusion is associated with risk and adverse
outcomes. It is positively correlated with an increased risk of multi-organ
failure, infection, critical care admission and mortality.

It is important to minimise transfusion by:

• Controlling haemorrhage effectively.

• Using red cell salvage as much as possible.

• Transfusing packed red cells for an indication, not just to improve a
number postoperatively (see page 118).

• Where red cell transfusion is indicated postoperatively, giving the
minimum number needed and rechecking. For example, many
mothers who do need a postoperative blood transfusion will only
need one unit, and the next unit should only be prescribed after a
further check.

• Using an appropriate amount of crystalloid. There is no single
figure: perhaps up to a couple of litres of Hartmann’s solution with
red cells. When blood loss exceeds 3,000 mL then empirical
transfusion of FFP as above becomes important.

Anticipation and prediction

Massive obstetric haemorrhage can happen in any delivery, whether
vaginal or caesarean, with no warning. Prediction is important but the
nature of obstetric practice is the experience of sudden bleeding.

Certain operations carry a greater risk. Women having intrapartum
caesarean birth are at moderate risk – though see risk factors below.
There is a high risk of massive obstetric haemorrhage in operations for

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examination under anaesthesia, perineal repair, and manual removal of
placenta.

Caesarean birth in labour, especially where labour has been induced,
labour is prolonged and an antepartum oxytocin infusion has been used,
is regularly followed by PPH. This situation becomes far worse if
chorioamnionitis is present – an exhausted and infected uterus may be
refractory to all oxytocic drugs.

Uterine angle tears and consequent haemorrhage may follow extraction
of a fetal head deeply embedded into the pelvis, especially in a deflexed
occipito-posterior malposition. Bleeding from angle tears can be
concealed even until after the mother has reached recovery.

Postpartum haemorrhage is more commonly associated with magnesium
infusions, multiple pregnancy, polyhydramnios, previous PPH, black and
south Asian ethnicity, social deprivation or isolation, obesity, prolonged
labour, and primiparous mothers over 40 years old.

Where a delivery is known to be one with a high risk of massive
haemorrhage, e.g., placenta praevia, especially with previous caesarean
birth, myomectomy scars, uterine fibroids, chorioamnionitis, placental
abruption or previous third-stage complications, anticipative steps are
essential.

• Antenatal anaemia should be checked and corrected in the
antenatal period if possible [45]. Iron-deficiency anaemia will reduce
the ability to tolerate haemorrhage and may contribute to uterine
atony through depleted uterine myoglobin levels.

• A consultant should perform all elective or emergency surgery.

• A consultant should give any anaesthetic.

• Adequate intravenous access (two large bore cannulas) should be in
place before surgery starts.

• Check blood availability, whether electronic issue compatible or
crossmatch.

• Consider inserting a preoperative arterial line.

• Ensure the availability of intraoperative cell salvage.

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Estimation of blood loss and its effects

Estimation is a continual process to keep the mother’s state under
review. Visual estimation of peripartum blood loss is inaccurate; include
clinical signs and symptoms in the assessment of haemorrhage [45].

The circulating blood volume at term can be taken to be 100 mL kg-1 [42]
(in the case of morbid obesity this will be less) you should calculate the
assumed starting blood volume, taking into account pre-theatre losses, to
determine the proportion of blood that the mother has lost, in order to
compare it with the standard haemorrhage classes.

The typical volumes are given for mothers with booking weights of 50 kg
or 90 kg. The effects of preoperative haemoglobin concentration should
also be taken into effect. This is not a treatment algorithm but rather an
indication of the effects of various volumes of blood loss.

Class 1 Up to 15% No change in vital signs; use
50 kg: up to 750 mL salvaged red cells.

90 kg: up to 1350 mL

Class 2 15-30% Peripheral vasoconstriction; use
50 kg: 750-1500 mL salvaged red cells, allogeneic
90 kg: 1350-2700 mL blood if not available.

Class 3 30-40% Peripheral vasoconstriction no
50 kg: 1500-2000 mL longer compensates, so systolic
90 kg: 2700-3600 mL blood pressure falls; use salvaged
red cells, check ABG and consider
transfusion or DCR.

Class 4 Over 40% Immediate threat to life with
50 kg: over 2000 mL cardiovascular collapse,
90 kg: over 3600 mL unconsciousness at 50% loss;
immediate ABG, DCR and
surgical intervention if not
already in progress.

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Large haemorrhages may be manageable with salvaged red cells alone if
bleeding is slower, and processing and reinfusion is done very well in
theatre.

With an arterial line in place you should make serial estimations of the
arterial pH, lactate and base deficit measurements to guide management.
Remember to send coagulation samples including fibrinogen levels
regularly in communication with the blood bank technician.

Obstetric surgical management

Surgical actions are as follows:

1. Inflate internal iliac artery balloons if present.

2. Call consultant to attend if not there.

3. Inspect and repair cervix.

4. Check for uterine cavity rupture.

5. Give uterotonics: rectal misoprostol 1000 mcg.

6. Tamponade uterine bleeding: uterine packing, Bakri balloon or
brace suture as indicated.

7. Attempt surgical haemostasis.

Bimanual compression staunches haemorrhage effectively.

Internal tamponade or packing may precede operative intervention.

If bleeding is excessive or of pharmacological measures fail to control
haemorrhage adequately, the obstetrician should consider further
surgical procedures, such as internal iliac ligation, hysterectomy, B-Lynch
suture (brace suture) or haemostatic square suture. Any obstetrician who
does not feel competent to perform any of the above should immediately
call a colleague to assist or, if necessary, a gynaecological or vascular
surgeon.

Hysterectomy is indicated if bleeding continues despite deployment of an
intrauterine balloon. It should not be delayed until the mother is in
extremis or while less definitive procedures with which the surgeon has
little experience are attempted [45].

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As the obstetric anaesthetist, you should check that the operating
obstetric surgeon has requested consultant assistance.

Pharmacological treatment of uterine atony

The drugs described here are oxytocic agents. Remember that in the case
of haemorrhage you should also administer tranexamic acid (page 124).

Syntometrine (oxytocin 5 units with ergometrine 500 mcg) is the
standard prophylaxis for vaginal delivery, given intramuscularly at the
delivery of the infant. This is used for most vaginal deliveries although it is
possible that it may be replaced by oxytocin as a result of the 2011
maternal mortality report [43] and 2016 RCOG guidelines [45]. Oxytocin
causes significantly less nausea and hypertension.

As the obstetric anaesthetist, you hold primary responsibility for the
following measures.

Oxytocin (Syntocinon) should be given by intravenous bolus (5 units;
dilute 10 units into 10 mL with sodium chloride 0.9% solution), usually
repeated once, (except as below). Follow this with an infusion of 20 units
oxytocin in 50 mL sodium chloride 0.9% solution starting at 15 mL h-1 as
standard, or 20 mL h-1 for higher-risk cases. Reduce this by 5 mL h-1 every
30 minutes or when the uterus has adequate tone.

Administer oxytocin in limited dose and slowly. Administering an
intravenous bolus injection of 10 units oxytocin can induce chest pain
accompanied by signs of myocardial ischaemia [44]. Especially but not
only in doses above 5 units, it can cause hypotension and circulatory
collapse if given in the presence of hypovolaemia or any form of shock,
through marked reduction in systemic vascular resistance. This drug must
be given by infusion at the slowest effective rate in cardiac disease or
pulmonary oedema. Oxytocics are however necessary to reduce blood
loss.

In these cases, and if there is no treatment plan in the notes, make up the
standard postpartum infusion, omitting the bolus dose altogether and
commencing the infusion at 25 mL h-1 for a maximum of 30 minutes. This
will deliver up to 5 units oxytocin. Keep in constant communication with

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the obstetrician about the state of uterine contraction. Reduce the dose
as soon as possible and in any case to 10 mL h-1 at thirty minutes. All such
cases must be discussed with a consultant.

Ergometrine 50-100 mcg by intravenous injection (make up 500 mcg to
10 mL with sodium chloride 0.9% solution; give 1-2 mL at a time repeated
as necessary). Intravenous ergometrine will act within 40 seconds; when
given intramuscularly (500 mcg) it acts within about seven minutes,
perhaps more with a shocked circulation. Ergometrine is a hypertensive
agent and so is relatively contraindicated in pre-eclampsia, other
hypertensive conditions, and migraine. This drug is best used with care in
severe pre-eclampsia and many cases of heart disease; if haemorrhage
control is needed nonetheless then use arterial line monitoring and doses
of 25-50 mcg. Ergometrine is safe and effective when given in small,
monitored, intravenous doses. If given IM, the dose may be repeated
after 2 hours [214].

Carboprost (Hemabate; a 15-methyl prostaglandin F2α analogue) is
indicated for uterine atony unresponsive to ergometrine or oxytocin. It is
given as an intramuscular dose of 250 mcg repeated up to every 15
minutes in severe cases (no more than eight doses or 2000 mcg).

Side-effects include nausea, vomiting, flushing, bronchospasm, hypoxia
(abnormal ventilation-perfusion ratio and intrapulmonary shunt fraction)
and hypertension. The mother is likely to suffer severe diarrhoea.
Excessive dosage may cause uterine rupture. 85% of mothers respond to
the first dose.

Carboprost is kept in the obstetric theatre refrigerator. Carboprost must
not be given intravenously. Intravenous administration is associated with
severe bronchospasm, systemic and pulmonary hypertension. Intra-
myometrial injection is no longer practised and should not be done.

Maternal asthma is a strong relative contraindication. It may be used with
caution in asthmatic mothers, weighing the severity of asthma against
the urgency of the need to increase uterine tone. Seek senior help and
advice.

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Oxytocin bolus followed by infusion
15-20 ml h-1

Good tone? Yes

No
Recheck all drug use; repeat oxytocin bolus
carefully and consider increasing infusion rate

Good tone? Yes

No Specific handover
Ergometrine; repeat as to midwife

necessary

Good tone? Yes Offer misoprostol

No

Carboprost; consider escalating case with
senior staff; offer misoprostol; specific
handover to midwife

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Misoprostol (a prostaglandin E1 analogue) may be given rectally at a dose
of 1000 mcg [45]. Offer this when the surgeon checks the birth canal. It is
often used when the mother has had some atony requiring higher dose
oxytocin or another uterotonic agent, to maintain tone in the postnatal
period. This will probably cause gastrointestinal symptoms such as
diarrhoea.

Use of red blood cells

The blood bank phone number is 25322 (bleep 2169). Use 25398 for
emergency haemorrhage.

Seek the advice of a consultant haematologist in coagulopathy or
massive haemorrhage.

Do not attempt to manage massive haemorrhage on your own.
Discuss potential cases with a senior colleague and call for help if it
happens.

Send samples (FBC and coagulation screen and fibrinogen) every hour
or more often as indicated.

If available, use TEG to guide therapy.

You must check every infused unit of blood against the mother’s verified
wristband, and verbally if she is conscious. There is detailed advice about
managing blood transfusions in the Anaesthetists Handbook. You must
make a record of a valid, defined, and justifiable indication for every
blood transfusion.

Emergency O Rh D negative blood

Several units are maintained in the blood fridge in labour ward theatres.
You should not use them if the mother has red cell antibodies – call blood
bank. (O-negative flyers are clinically safe with PD antibodies.) You must
inform blood bank if these units are used, using the green form kept with
the unit. Switch to group-specific blood as soon as is feasible [45].

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Electronic issue of blood

Blood issued electronically will be in theatre swiftly. To be suitable for
electronic issue of blood, a mother must fulfil all the following criteria:

1. Two serum samples processed by blood bank, at least one within
the previous three days for mothers in the third trimester. The
antenatal screen (listed as ANC, FAN or BAN on CRRS) can be used
as a reference sample but the current sample must be a valid ‘group
and screen’ (GA) tested here at UHCW within the last 72 hours. The
two samples must have been taken at different times.

2. Both samples to agree with each other on blood group.

3. Antibody screen negative on every current and reference sample.

In practice, if a recent GA (group and screen) sample and a BAN or second
GA sample are on CRRS without an antibody flag then the mother is
suitable for electronic issue. However, this is dependent on their recent
history of any blood transfusion.

Rhesus negative mothers will very likely have received prophylactic anti-
D. This makes them PD-antibody positive and currently unable to have
blood electronically issued.

Indications for perioperative transfusion

Try to maintain circulating haemoglobin with cell salvage if possible. If it
is not, then consider allogeneic blood transfusion or switch to DCR as
described above.

ICS (intraoperative cell salvage)

See page 323 for the main chapter on ICS.

ICS can be used in the management of obstetric haemorrhage. There is
some weak evidence that its use reduces allogeneic blood transfusion
[46,47]. If not already set up, it may be possible to set it up when
haemorrhage starts. It can be set up in less than five minutes and is
indicated in the emergency setting if bleeding continues and you expect
there to be more to salvage and process. Ensure that any large abdominal

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swabs used to mop up blood are soaked in sodium chloride 0.9% solution
(IV use) as soon as possible as this helps return of good quality red cells:
ask the scrub practitioner.

Always send for senior assistance if you are in this position – the mother
is haemorrhaging.

Check with the ODP and consider sending for another ODP.

Indications for postoperative transfusion

There are no firm universal criteria for initiating red cell transfusion in the
postoperative phase. Base your decision to provide blood transfusion on
both clinical and haematological assessment [45].

Tachycardia after the end of the operation warrants careful review. Use
the mother’s body mass and estimated blood loss to calculate the class of
haemorrhage. Postoperative transfusion may be indicated by a class 2
haemorrhage (more than 15% circulating volume) or above that has not
been treated with salvaged red cells. Check the mother’s lactate and base
deficit to inform this indication. For example, a mother with booking
mass 50 kg has suffered a 20% class 2 haemorrhage with 1000 mL blood
loss.

The following guideline is adapted from SIGN [48] and the BSH guidelines
[49]. The original guidelines were drawn up for elective surgery in non-
pregnant patients; we recommend this for mothers. Haemoglobin levels
will take a few hours to settle after massive haemorrhage and
transfusion.

• We have a single unit policy for haemodynamically stable patients.
‘Don’t use two until you review.’

• Transfusion is unlikely to be justified at haemoglobin levels above
100 g L-1.

• Transfusion is almost always required at haemoglobin levels below
70 g L-1.

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• Patients with cardiovascular disease, or those expected to have
covert cardiovascular disease are likely to benefit from transfusion
when their haemoglobin level falls below 90 g L-1.

• Transfusion at levels between 70 g L-1 and 100 g L-1 is at discretion;
you should consider any postoperative symptoms such as
tachycardia, dyspnoea, and failure to mobilise. You should also
consider the preoperative haemoglobin level and all other relevant
factors.

• Red cells also contribute to haemostasis by their effect on platelet
margination and function. The optimal haematocrit to prevent
coagulopathy is unknown, but sufficient red cells will be required to
sustain haemostasis in patients with massive blood loss.

• Red cells also contribute to haemostasis by their effect on platelet
margination and function. The optimal haematocrit to prevent
coagulopathy is unknown, but experimental evidence suggests that
a relatively high haematocrit, possibly 35%, may be required to
sustain haemostasis in patients with massive blood loss.

Remember that mothers considered for blood transfusion may need
critical care and will probably need postpartum iron therapy.

Use of haemostatic blood components

Postpartum haemorrhage associated with atony or trauma is unlikely to
be associated with haemostatic impairment unless the diagnosis is
delayed [50]. Be careful with excessive use of FFP.

During 2021 we are intending to adopt the management principles and
practices associated with the OBS Cymru project [51]. This will include
use of measured blood loss instead of estimated, a stage 2 PPH call at a
lower threshold than the MOH call (1000 mL), a TEG6 protocol with
maternity theatres installation of an analyser machine, and use of
fibrinogen concentrate. Further information will follow as appropriate.

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FFP (fresh frozen plasma)

Aim for prothrombin time less than 20 seconds and activated partial
thromboplastin time ratio less than 1.5. Above this level there will be
increased surgical bleeding to complicate PPH.

Order FFP when you declare massive obstetric haemorrhage and
anticipate transfusing more than four units of allogeneic blood or
1200 mL salvaged blood. FFP is not indicated with transfusions limited to
four units RBC, but is needed after that. Consider using proportionately
more FFP in the case of placental abruption, but cryoprecipitate might be
a better choice in anticipated coagulopathy as below. FFP numbers vary
in the MOH packs as follows.

MOH pack issue

Always discuss the mother’s needs with the blood bank technician and
make appropriate orders. MOH packs are usually issued as follows:

• First pack is 4 RBC. FFP is not usually needed.
• Second pack is 4 RBC and 4 FFP. The second pack includes FFP to

match the first and second packs of 4 RBC.
• Third and subsequent packs are 4 RBC and 2 FFP.
• Order platelets and cryoprecipitate as needed.

You should vary the orders appropriately after any usage of O-negative
flyers before the MOH pack arrives, and with significant quantities of
salvaged red cells.

Four FFP are kept defrosted in blood bank but when these are used you
will have to allow up to forty minutes defrosting and transport time. FFP
is a high-volume infusion at 250 mL per unit.

Defrosted FFP can be returned to blood bank so long as it has stayed
within the cool chain. It can then be issued to other patients (within 24
hours of defrosting).

If no haemostatic results are available and bleeding is continuing, then,
after four units of red blood cells, administer two units of FFP [45]. Also
consider this for conditions with a suspected coagulopathy, such as

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placental abruption or amniotic fluid embolism, or where detection of
PPH has been delayed. Discuss with the on-call haematologist whether
cryoprecipitate would be a better choice.

Platelets

The therapeutic goal is to keep the platelet level above 50 × 109 L-1 in
acutely bleeding mothers; to do this use a transfusion trigger of
75 × 109 L-1 [45,52,53]. Anticipate need and order early for when required
if there is a rapidly falling count on repeat sample, or if a mother’s entire
blood volume has been replaced (approximately 100 mL kg-1). Platelets
may need to come from Birmingham. Liaise with the blood bank to
ensure that two adult doses of platelets are available locally and request
them to be sent if not; a decision to transfuse can be taken later. Only
send for platelets from blood bank to the clinical area when a decision to
transfuse has been made.

Empirical treatment may be indicated in massive transfusion. Consider
giving one pool of platelets with each four units of packed red cells (after
the first four). Liaise with the consultant haematologist if unsure.

Fibrinogen and cryoprecipitate

Fibrinogen is important in primary haemostasis through platelet
activation and aggregation, and in secondary haemostasis through fibrin
polymerisation. Levels rise during the third trimester of pregnancy to
twice those of non-pregnant levels. Fibrinogen deficiency develops early
when concentrated red cells are used to replace lost whole blood – it is
likely to be the first coagulation factor to deplete in a massive obstetric
haemorrhage. Low fibrinogen levels during operative surgery point to
serious trouble. Levels below 2 g L-1 are strongly predictive of massive
PPH, transfusion needs, surgical intervention and the need for critical
care [54,55,56]. This work is compelling though it is unclear whether the
low fibrinogen levels are a causative factor; no convincing intervention
studies are reported yet.

Aim for fibrinogen levels greater than 2 g L-1 during ongoing PPH [45].
Ensure that you request fibrinogen levels with any coagulation screen.

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Allow forty minutes defrosting and transport time. Cryoprecipitate has
less volume than FFP.

The adult dose is two pools (each pool containing five units, 100-200 mL
per bag).

If bleeding has progressed so that the uterus is a large bag of blood, it is
likely that the uterine contents will be a large fibrin clot. In this case
administer four pools (twenty units) of cryoprecipitate empirically
without waiting for the coagulation screen results.

Haemostatic failure

If severe pre-eclampsia, consumption coagulopathy or amniotic fluid
embolism (AFE) is suspected or there seems to be widespread
haemostatic failure not responding to FFP, give a pool of cryoprecipitate
followed by one adult therapeutic dose of platelets if bleeding persists.
Suspected AFE will require larger volumes of cryoprecipitate. Obtain fresh
coagulation results and haematology advice.

Consider and use systemic haemostatic agents as below.

Hypothermia causes and will worsen coagulopathy.

Use of systemic haemostatic agents

Tranexamic acid (Cyklokapron) – TXA

TXA is an antifibrinolytic agent which stabilises the formation of blood
clots, by inhibiting the conversion of plasminogen to plasmin. (It is a
synthetic lysine analogue, competitively inhibiting plasminogen lysine
binding sites and interfering with the action of plasminogen activators.)
Tranexamic acid is indicated in postpartum haemorrhage as a first-line
measure.

NICE guidance mandates the offer of tranexamic acid to adults
undergoing surgery who are expected to have at least moderate blood
loss (greater than 500 mL), and the administration of tranexamic acid to
be used routinely when cell salvage is used [57]. Given that the median
blood loss at caesarean birth is about 500 mL, and we process and

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reinfuse salvaged red cells in about 10% of cases, NICE guidance supports
a liberal approach.

You should make sure to give tranexamic acid promptly in all cases of
postpartum haemorrhage, regardless of whether the bleeding is due to
genital tract trauma or other causes [58], unless contraindicated. Make
sure it has been given if blood loss is 500 mL or more at vaginal birth or
1000 mL or more at caesarean birth. It is also indicated for
coagulopathy, including AFE.

The WOMAN trial reported in 2017 and confirmed the place of
tranexamic acid in PPH, alongside uterotonics. Tranexamic acid reduces
death due to bleeding in women with postpartum haemorrhage with no
adverse effects; when used for postpartum haemorrhage, tranexamic
acid should be given as soon as possible after bleeding onset [59].

Early treatment is the most effective, and late treatment is unlikely to be
beneficial. Treatment delay in use of TXA appears to reduce benefit; the
benefit appears to decrease by 10% for every 15-minute delay after
childbirth, with no benefit seen after 3 hours [60,61].

The World Maternal Antifibrinolytic (WOMAN) trial involved 20,060
women with postpartum haemorrhage (PPH), defined as blood loss
of:

• more than 500 mL after vaginal delivery.

• more than 1000 mL after caesarean birth.

• any amount that caused haemodynamic instability (inability to
maintain blood pressure).

Tranexamic acid reduced the risk of death from bleeding by 19%.
There were 155 deaths (1.5%) in the tranexamic acid group compared
with 191 (1.9%) in the placebo group, (risk ratio [RR] 0.81, 95%
confidence interval [CI] 0.65 to 1.00). This reduction in risk was still
seen after researchers adjusted the results to take into account the
underlying risk of bleeding between mothers (RR 0.78, 95% CI 0.62 to
0.98).

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The benefits were greater in those given tranexamic acid earlier. If
given before three hours the risk of death from bleeding was reduced
by 31%: 89 deaths (1.2%) versus 127 (1.7%) in the placebo group (RR
0.69, 95% CI 0.52 to 0.91). Tranexamic acid did not reduce the risk of
dying from bleeding if given more than three hours after birth, 66
deaths (2.6%) versus 63 (2.5%) (RR 1.07, 95% CI 0.76 to 1.51).

There was no difference between the groups in adverse events due to
blood clots, such as deep vein thrombosis, pulmonary embolus,
stroke, or heart attack.

Check delivery plans, and use tranexamic acid for prophylaxis, in
mothers at higher PPH risk. Use it as a blood-sparing measure for those
who decline the use of blood transfusion.

Tranexamic acid crosses the placenta and is present in breast milk but use
in the mother is not known to cause significant side effects in the
neonate.

Start with tranexamic acid 1 g intravenous load over 10 minutes and, if
bleeding is not brought under immediate control, a further 1 g over the
next hour. Suggested regimes are:

• The loading dose is 1 g (2 ´ 5 mL) slow IV over 10 minutes.

• If still at risk or continuing to bleed 30 minutes after the loading
dose, give 1 g maintenance infusion over one hour. Make up a
50-mL syringe with 1 g (10 mL) tranexamic acid and 10 mL 0.9%
sodium chloride; set the syringe driver to 20 mL h-1.

There are some cautions to the use of tranexamic acid.

• The potential for promoting thromboembolism remains unclear and
lends importance to ensuring prophylaxis with LMWH. Use of TXA
after a confirmed thromboembolic event in pregnancy is a
consultant decision.

• Epilepsy: weak evidence prompts caution with high doses in those
with a history of epilepsy.

• Renal impairment: it is almost entirely excreted in urine.

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• Disseminated intravascular coagulopathy: use remains controversial
and complex. Seek haematological advice if considering use.

Prescribe postoperative thromboprophylaxis with enoxaparin to prevent
further fibrin deposition and an aggravated prothrombotic state. Do not
withhold enoxaparin thromboprophylaxis in mothers recovering from
haemorrhage.

Calcium chloride

Maintenance of calcium concentrations will help to prevent
coagulopathy. If transfusing donor red cells or reinfusing salvaged red
cells, administer 10 mL calcium chloride 10% solution slowly to maintain
ionised Ca2+ above 1.0 mmol L-1, or per four units of red cells or
equivalent.

Recombinant activated Factor VII (rFVIIa; NovoSeven)

Use of rFVIIa is only recommended as part of a clinical trial [45] and it is
no longer stocked in Coventry.

Mothers who refuse blood transfusion

Refusal of consent can be on religious grounds (Jehovah’s Witness due to
concern about the sacred nature of blood, Rastafarian due to concern
about contamination of the body etc.) or can be because of personal
beliefs whether apparently rational or not, or simply concern about the
risks of allogeneic blood transfusion. You may be asked to speak with a
mother who is considering declining blood transfusion. This may be done
because of our expertise in running the red cell salvage programme,
which is valued by the obstetricians and mothers alike. Give adequate
time to discuss these matters with the mother and record the disclaimer,
including the various types of blood components and fractions available
and whether they are acceptable to the mother [62]. Refer to the current
hospital guideline on refusal of consent for transfusion and complete the
paperwork as far in advance as possible – the form describing acceptable
components is on the hospital intranet.

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Red cell salvage will probably be acceptable – see page 326. Discuss the
process in detail so that she knows what she is agreeing to.

Clearly the principles of damage control resuscitation cannot be applied
to a mother declining consent for the primary blood components:
allogeneic red cells, FFP or platelets. Any such case in progress must be
immediately referred to a consultant if not already involved in
management, and to the labour ward coordinator to contact the hospital
legal team.

Extubation after massive obstetric haemorrhage

Management of massive obstetric haemorrhage as above involves
repeated ABG samples and monitoring of serial lactate and base deficit
levels to assess the adequacy of resuscitation. Extubating after such
haemorrhage must be an active decision in which this adequacy is
explicitly considered. Haematological deficits, metabolic derangement
and hypothermia must be corrected before extubation. Persistent
abnormal lactate and base deficit levels may indicate inadequate
resuscitation, but a deteriorating trend may also indicate unrecognised
ongoing bleeding. Consider reoperation, or, if ongoing bleeding has been
excluded, level 3 critical care.

Mothers must be adequately resuscitated, and bleeding stopped prior to
extubation following general anaesthesia [63]. Seek evidence of adequate
resuscitation prior to extubation.

Balloon occlusion catheters and fluoroscopy procedures

Bilateral placement of catheters into the internal iliac arteries, with
perioperative balloon occlusion or transcatheter arterial embolisation has
been used effectively to control massive obstetric haemorrhage. It
promotes safety but does not reduce the incidence of hysterectomy [64].

In this procedure, a radiologist inserts bilateral catheters into the
contralateral internal iliac arteries via the femoral arteries. Intravascular
balloon inflation provides temporary control.

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However, these are prolonged procedures usually needing careful
planning and taking place in the fluoroscopy suite in the radiology
department. (We hope to have a hybrid theatre in a few years’ time, but
this facility is not yet available.) Interventional radiology is very unlikely
to be effectively employed in an acute situation if catheters are not
already in place due to the difficulty of maintaining damage control
resuscitation procedures during transfer to fluoroscopy. It is not easily
available as an on-call procedure, if at all.

The exception to this is when the haemorrhage is under control
temporarily and it is possible to use foam embolisation for permanent
control. This might be appropriate, including as an on-call procedure, for
fibroid embolisation.

Indications

Perioperative balloon occlusion is indicated for a high risk of placenta
accreta based on a history of previous caesarean birth along with
sonographic findings pointing to anterior placenta praevia [65]. This
probabilistic approach does lead to a significant incidence of unnecessary
intervention. MRI imaging or transvaginal ultrasound should also be
available to augment the diagnosis. There is however no certainty in
diagnosis until direct surgical visualisation.

Management

Inform a consultant if they are not already involved.

Where a case is being planned, the consultant who will be responsible for
the case must be involved and decide on the anaesthetic technique.
Experience has shown that the catheter insertion is quite uncomfortable,
particularly as it requires two insertions. The choice of anaesthesia for
such a planned case may well be epidural catheter placement and dosing
followed by general anaesthesia. If so, we recommend placing the
epidural before the femoral artery catheters. Using an epidural will also
help to keep the mother’s legs still and reduce the chance of displacing
the arterial catheters once placed. The epidural can be placed in the
lumbar spine if horizontal incision is planned or higher in the thoracic

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spine if vertical incision is planned. General anaesthesia can be
administered when arriving back in the maternity theatre. This will need
planning around the insertion of a trauma line for massive transfusion
that is becoming standard in these cases.

The mother will need to have had a coagulation screen and renal function
check (urea and creatinine) before the procedure – make sure this has
been done within a week of the procedure if planning a case.

Liaise with the radiologist about timing and dose of any heparin they may
wish to use in relation to catheter removal after the case. It is not likely
that heparin will be used.

Balloon inflation will not halt all blood flow to the uterus but can be
expected to reduce pulse pressure distal to the occlusion, this reducing
intraoperative blood loss. This may prevent hysterectomy or reduce
blood flow into the operative field and reduce the incidence of
complications of emergency hysterectomy. This marked reduction of
bleeding at inflation gives time to assess the optimal management.

Complications

Thromboembolism of the iliac arteries, bladder and rectal wall necrosis,
leg ischaemia and cauda equina syndrome can result. Buttock
claudication may be the most common complication. There may be
anxiety at occlusion times over twenty minutes, though this must be
balanced against the risks posed by a haemorrhaging invasive placenta,
and many units use much longer times.

Catheter placement can result in uteroplacental insufficiency and fetal
compromise [66] – there should be fetal monitoring throughout the
procedure. Take terbutaline to fluoroscopy in case of fetal distress due to
contractions (250 mcg may be given subcutaneously).

34. Confidential Enquiries into Maternal Deaths. Why Mothers Die 1997-99.
London: RCOG Press, 2001; page 94.

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35. Maitra M, Woodman J, Porter M, Fairfield A. Post Partum Haemorrhage.
UHCW clinical guideline CG971, September 2019.

36. Macphail S, Talks K. Massive post-partum haemorrhage and management of
disseminated intravascular coagulation. Current Obstetrics and Gynaecology
2004; 14:123-31.

37. Butwick AJ, Liu C, Guo N, Bentley J, Main EK, Mayo JA, Shaw GM,
Stephansson O. Association of Gestational Age with Postpartum Hemorrhage:
An International Cohort Study. Anesthesiology 2021(June); 134:874-86.

38. de Lange N, Schol P, Lancé M et al. Restrictive Versus Massive Fluid
Resuscitation Strategy (REFILL study), influence on blood loss and hemostatic
parameters in obstetric hemorrhage: study protocol for a randomized
controlled trial. Trials 2018; 19:166.

39. Giannoudi M, Harwood P. Damage control resuscitation: lessons learned. Eur
J Trauma Emerg Surg 2016; 42:273-82.

40. MBRRACE-UK. Saving Lives, Improving Mothers’ Care: Lessons learned to
inform maternity care from the UK and Ireland Confidential Enquiries into
Maternal Deaths and Morbidity 2014-16. Oxford: MBRRACE, November 2018,
page 23.

41. Mahoney BA, Smith WA, Lo DS, Tsoi K, Tonelli M, Clase CM. Emergency
interventions for hyperkalaemia. Cochrane Database Syst Rev 2005; Issue 2
Art. No.: CD003235. DOI: 10.1002/14651858.CD003235.pub2.

42. MBRRACE-UK. Saving Lives, Improving Mothers’ Care: Lessons learned to
inform maternity care from the UK and Ireland Confidential Enquiries into
Maternal Deaths and Morbidity 2016-18. Oxford: MBRRACE, December 2020,
page 62.

43. Saving Mothers’ Lives: Reviewing maternal deaths to make motherhood safer
2006–2008. Br J Obs Gynaecol 2011; 118 supplement 1, page 69.

44. Svanström MC, Biber B, Hanes M, Johansson G, Näslund U, Bålfors EM. Signs
of myocardial ischaemia after injection of oxytocin: a randomized double-
blind comparison of oxytocin and methylergometrine during Caesarean
section. Br J Anaesth 2008; 100:683-9.

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Obstetric haemorrhage

45. Mavrides E, Allard S, Chandraharan E, Collins P, Green L, Hunt BJ, Riris S,
Thomson AJ on behalf of the Royal College of Obstetricians and
Gynaecologists. Prevention and management of postpartum haemorrhage.
BJOG 2016; DOI: .10.1111/1471-0528.14178 (Green-top Guideline no. 52).

46. Elagamy A, Abdelaziz A, Ellaithy M. The use of cell salvage in women
undergoing cesarean hysterectomy for abnormal placentation. Int J Obstet
Anesth 2013 Nov; 22(4):289-93.

47. Khan KS, Moore PAS, Wilson MJ, Hooper R, Allard S, Wrench I, et al. Cell
salvage and donor blood transfusion during cesarean section: A pragmatic,
multicentre randomised controlled trial (SALVO). PLoS Med 2017;
14(12):e1002471.

48. Scottish Intercollegiate Guidelines Network at
http://www.guideline.gov/summary/summary.aspx?view_id=1&doc_id=5693

49. British Committee for Standards in Haematology. Guidelines on the
Management of Massive Blood Loss. BCSH: web access January 2008.

50. Collis RE, Collins PW. Haemostatic management of obstetric haemorrhage.
Anaesthesia 2015; 70:78-e28.

51. Bell SF, Kitchen T, John M, et al. Designing and implementing an all Wales
postpartum haemorrhage quality improvement project: OBS Cymru (the
Obstetric Bleeding Strategy for Wales). BMJ Open Quality 2020; 9:e000854.
doi:10.1136/ bmjoq-2019-000854

52. Association of Anaesthetists of Great Britain and Ireland. AAGBI guidelines:
the use of blood components and their alternatives 2016. Anaesthesia 2016;
71:829-42.

53. Green L, Connolly C, Cooper TK, Cho G, Allard S on behalf of the Royal College
of Obstetricians and Gynaecologists. Blood Transfusion in Obstetrics (Green-
top Guideline no. 47), May 2015.

54. Charbit B, Mandelbrot L, Samain E et al. The decrease of fibrinogen is an early
predictor of the severity of postpartum haemorrhage. J Thromb Haemost
2007; 5:266-73.

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55. Cortet M, Deneux-Tharaux C, Dupont C, Colin C, Rudigoz RC, Bouvier-Colle
MH, et al. Association between fibrinogen level and severity of postpartum
haemorrhage: secondary analysis of a prospective trial. Br J Anaesth 2012;
108:984-9.

56. Butwick AJ. Postpartum haemorrhage and low fibrinogen levels: the past,
present and future. Int J Obstet Anesth 2013; 22:87-91.

57. National Institute for Health and Care Excellence. Blood transfusion. London:
NICE, November 2015; NG24.

58. World Health Organisation. Updated WHO Recommendation on Tranexamic
Acid for the Treatment of Postpartum Haemorrhage. WHO, Geneva; October
2017.

59. WOMAN Trial Collaborators. Effect of early tranexamic acid administration on
mortality, hysterectomy, and other morbidities in women with post-partum
haemorrhage (WOMAN): an international, randomised, double-blind,
placebo-controlled trial. The Lancet 2017; 389:2105-16.

60. Gayet-Ageron A, Prieto-Merino D, Ker K, Shakur H, Ageron FX, Roberts I;
Antifibrinolytic Trials Collaboration. Effect of treatment delay on the
effectiveness and safety of antifibrinolytics in acute severe haemorrhage: a
meta-analysis of individual patient-level data from 40 138 bleeding patients.
Lancet 2018 Jan 13; 391(10116):125-32.

61. Shakur H, Beaumont D, Pavord S, Gayet-Ageron A, Ker K, Mousa HA.
Antifibrinolytic drugs to treat heavy bleeding after childbirth. Cochrane
Database of Systematic Reviews 2018, Issue 2. Art. No.: CD012964. DOI:
10.1002/14651858.CD012964.

62. Klein AA, Bailey CR, Charlton A, Lawson C, Nimmo AF, Payne S, Ruck Keene A,
Shortland R, Smith J, Torella F, Wade P. (2019), Association of Anaesthetists:
anaesthesia and peri-operative care for Jehovah’s Witnesses and patients
who refuse blood. Anaesthesia 2019; 74: 74-82. doi:10.1111/anae.14441.

63. MBRRACE-UK. Saving Lives, Improving Mothers’ Care: Lessons learned to
inform maternity care from the UK and Ireland Confidential Enquiries into
Maternal Deaths and Morbidity 2013-15. Oxford: MBRRACE, December 2017,
page 67.

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64. Taylor NJ, Russell R. Anaesthesia for abnormally invasive placenta:
a single-institution case series. Int J Obstet Anesth 2017; 30:10-15.

65. Mok M, Heidemann B, Dundas K, Gillespie I, Clark V. Interventional radiology
in women with suspected placenta accreta undergoing caesarean section. Int
J Obstet Anesth 2008; 17:255-61.

66. Sadashivaiah J, Wilson R, Thein A, McLure H, Hammond CJ and Lyons G. Role
of prophylactic uterine artery balloon catheters in the management of
women with suspected placenta accreta. Int J Obstet Anesth 2011; 20:282-7.

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Intravenous infusion techniques

Intravenous infusion techniques

This section details unusual techniques that may become necessary in the
event of massive haemorrhage or lost intravenous access.

Belmont® rapid infuser

The Belmont® rapid infuser is a self-contained fluid management system.
It allows for the rapid and precise administration of blood products in an
emergency where there is profuse and ongoing haemorrhage.

It will automatically warm blood products (if the flow rate exceeds
5 mL min-1) and remove air bubbles from the system.

It would be appropriate to have a Belmont rapid infuser set up and
primed, ready to run, in cases where massive postpartum haemorrhage is
anticipated. The ODPs can set up and prime the infuser for you but it will
be your responsibility to operate it.

If you are unfamiliar with Belmont rapid infuser operation, ask someone
to demonstrate it to you.

The system consists of a machine and a disposable set with three fluid
spikes that lead into a central reservoir – see the picture below. Blood
products are drawn from this reservoir into the pump where they are
warmed. Air bubbles are automatically detected and drawn back into the
reservoir and eventually vented out of the system. The warmed products
are then delivered to the mother.

Flow rates from 2.5 mL min-1 up to 1000 mL min-1 can be achieved,
depending on the size and quality of the intravenous access. It is
therefore crucial that you obtain large-bore intravenous access. This
might mean placing a Vascath into the internal jugular vein, although be
careful not to get task-focused trying to achieve this if you have adequate
peripheral access. There is a pressure limiter that will help to prevent
damage to the mother’s veins.

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Belmont® 3-Spike Disposable Set OAH14-2021
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These high flow rates are necessary to keep up with the rapid
haemorrhage that can occur in certain circumstances, such as invasive
placentation as in placenta accreta, or in the presence of uterine fibroids
preventing adequate uterine tone. This system will sometimes be the
only piece of available equipment that will be able to sustain an infusion
rate high enough to manage these cases adequately.

To achieve these flow rates, it is necessary to not only have good, large
bore intravenous access but also a dedicated team to operate the
Belmont. You will need at least two and more likely three people
dedicated to the Belmont, including an ODP and an anaesthetist, so that
blood products can be quickly taken from the fridge or transfer box,
checked against the mother’s details, and then fed into the Belmont.

It is also useful to have an incontinence sheet on a Gratnell theatre
trolley, onto which empty bags of blood products can be placed. This will
allow you to go back and record exactly how many products have been
administered, their G number, and the volume of each product.
Recording all this information at the moment of haemorrhage can be
difficult.

Platelets and cryoprecipitate cannot be infused through the Belmont
rapid infuser.

Training on the Belmont

There are some very useful educational videos on the trust website that
will talk you through setting up, operating and troubleshooting the
Belmont. These can be found from the home page under:

Directorates & departments | Theatres |Belmont rapid infuser training
videos

Practising on the rapid infuser can use a lot of consumables, especially
intravenous fluids, when operating the system and giving bolus doses. To
avoid the waste of such fluid and the mess in a confined space, recycle
the fluid from one fluid bag [67]. This is done by setting up the rapid
infuser with a bag of crystalloid and cut a small opening in the top corner
of the bag. Pour out 200 mL and then feed the giving set into the hole,

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taping it into place. All fluid drawn from the intravenous bag is then run
through the system and fed back into the original bag.

Intraosseous access

All resuscitation and anaesthetic drugs can be given via the IO route. The
humeral route is now the preferred bony access for any intraosseous
access in obstetrics.
Fluids should be administered under pressure.
An EZ-IO driver is available for use – theatre 2.

Indications

The need for rapid reliable vascular access and fluid resuscitation in a
mother for whom intravenous access is difficult or too slow. Each
humeral needle will provide an approximate equivalent of an 18-swg
intravenous needle (green). You are unlikely to be able to get the
Belmont rapid infuser to work briskly on this.

Contraindications

Bone trauma, prostheses, or infection; intraosseous access through that
bone in the last 48 hours.

Intraosseous method

For obstetric haemorrhage, access above the uterus is necessary so that
fluids and drugs are not lost into the abdomen. Use the humeral head on
the side at which you have most access, usually the left. Using the
proximal humerus is associated with more rapid insertion and less pain
(in the non-anaesthetised patient).
Bend the mother’s elbow and put their hand on their abdomen to rotate
the humerus and remove the tendon of the long head of biceps; if this is
not possible use medial rotation of a straight arm. Palpate the surgical
neck of the humerus to locate the greater tubercle. The insertion site is
the most prominent aspect of the greater tubercle, approximately 1-2 cm

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above the surgical neck. This is said to feel like a golf ball on a tee, with
the surgical neck being the point where the golf ball meets the tee.

1. Clean the insertion site.

2. Attach the long yellow 45-mm needle to the EZ-IO driver.

3. Local anaesthesia to the skin is optional.

4. Support the limb and stabilise the bone.

5. Push the needle tip through the skin and soft tissue at a 45-degree
angle, angled horizontally towards the opposite iliac crest and at a
45-degree angle downward, until the tip rests against the bone of
the greater tubercle. Do not drill through skin or soft tissue.

6. For the needle to fit appropriately, at least 10 mm (one black
marker line on the needle) should still be visible before drilling.

7. Squeeze the driver trigger and apply moderate steady pressure.
Gently drill into the humerus 2 cm at full drill speed until there is a
sudden decrease in resistance or until the hub reaches the skin in
an adult. The hub of the needle set should be perpendicular to the
skin.

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8. After this change in resistance, stop and stabilise the hub with one
hand, pull the driver off and then unscrew the stylet counter-
clockwise and remove it.

9. The needle should still feel firmly seated in bone. Aspiration of
marrow helps to confirm placement, but this is not always possible.

10. Samples for laboratory analysis (e.g., group and save) can now be
taken. This is the only time that a syringe should be directly
connected to the catheter hub. Do not take an arterial blood gas
sample – marrow will block the analyser.

11. Place the stabiliser over the hub and attach a primed extension set.
12. Flush the system with 2 mL 2% lidocaine slowly to reduce pain, wait

60 seconds, give 10 mL sodium chloride 0.9% solution, and attach
an IV giving set. ‘No flush, no flow’.
The intraosseous needle should now be firmly seated. Secure the arm in
place and do not lift it – lifting will dislodge the IO needle. In the case of
pain on injection, flush a further 1 mL 2% lidocaine. Flush the needle with
at least 10 mL of fluid after drug administration.
Due to the intrinsic resistance of the intraosseous space, infusions
commonly do not flow effectively with gravity alone and need to be
administered under pressure e.g., using pressure bags, syringe driver or
manual flushing.
Assess the IO site frequently for signs of extravasation and do not leave in
place longer than 24 hours.

67. Seal G, Stables A, Mercer SJ. Training for damage control resuscitation using a
rapid infuser. J R Army Med Corps 2017; 163:76.

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Local anaesthetic toxicity

Local anaesthetic toxicity

For active management with checklist® M-QRH

Epidural injections and infusions create serious risks for mothers if given
inadvertently through the intrathecal or intravenous routes. All epidural
administrations must be given by doctors, nurses, or midwives and in
areas where there is immediate availability of an emergency team able to
treat subsequent problems.

All these cases must be reported on clinical adverse event forms.

Systemic toxicity to local anaesthetics leads to central nervous excitability
and convulsions. Cardiotoxicity also occurs and usually involves torsade
de pointes – a form of ventricular tachycardia characterised by a
polymorphous electrocardiographic appearance, delayed repolarisation,
and a prolonged QT interval – or refractory ventricular fibrillation [68].

Hypokalaemia and hypomagnesaemia are predisposing factors.
Hypomagnesaemia is an occasional finding in late pregnancy.

Avoid these adverse effects by minimising the use of strong
concentrations (above 0.1%) for epidurals as far as possible.

Life-threatening intravenous administration of local anaesthetic can occur
at any time that an epidural dose is being given, either down an epidural
catheter or wrongly into an intravenous cannula. The NPSA safety alerts
requiring incompatible NRFit connectors have now been implemented.
However, no physical barrier is absolute, and vigilance is still required,
especially during epidural top-up.

For life-threatening cardiotoxicity administer life support as necessary
followed promptly by the specific treatment for local anaesthetic toxicity.
There is now a professional consensus surrounding the use of
intravenous 20% lipid emulsion to treat severe local anaesthetic toxicity
with neurological or cardiovascular involvement [69].

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Recognition

Signs of severe toxicity:
• Sudden alteration in mental status, severe agitation, or loss of

consciousness, with or without tonic-clonic convulsions.
• Cardiovascular collapse: sinus bradycardia, conduction blocks,

asystole and ventricular tachyarrhythmias may all occur.
• Local anaesthetic (LA) toxicity may occur during or a little time after

an initial injection.

Immediate management

• Stop injecting the local anaesthetic.
• Call for help and ask someone to get the lipid rescue bag and

guideline from the resuscitation trolley in the maternity theatres
lobby. Use the Quick reference Handbook.
• Maintain the airway and, if necessary, secure it with an
endotracheal tube.
• Give 100% oxygen and ensure adequate lung ventilation
(hyperventilation may help by increasing plasma pH in the presence
of metabolic acidosis).
• Prevent aortocaval compression.
• Confirm or establish intravenous access.
• Control seizures: give a benzodiazepine, thiopental or propofol in
small incremental doses.
• Assess cardiovascular status throughout.

Treatment

• Check the protocol on the lipid bag.
• In circulatory arrest, commence CPR and give lipid rescue

continuing CPR throughout.

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