Awareness Anaphylaxis MH Airway algorithms

Question 1

Q2 — Accidental awareness

a) What is accidental awareness under general anaesthesia
(AAGA)?

Answer 1

Awareness is said to have occurred when the patient has an explicit recall of the intraoperative events associated with or without pain.

Question 2

b) What is the overall incidence of awareness under general
anaesthesia and the estimated awareness incidence for a
caesarean section under general anaesthesia as per the NAP5
study?

Answer 2

● The overall incidence of patients reporting an incidence of awareness under general anaesthesia is around 1:19,000.

● The estimated awareness incidence in a caesarean section under general anaesthesia is around 1:670 patients.

Question 3

c) List the monitoring devices that can be used to help reduce the incidence of awareness under general anaesthesia.

Answer 3

Bispectral Index and M-Entropy™ —
both provide a processed EEG as
a measure of cortical suppression.
They give a number (dimensionless
index) to be interpreted.

● Narcotrend®.

● aepEX® device —
uses auditory evoked potentials to derive the depth
of anaesthesia.

● Another technique is the isolated forearm technique.

Question 4

d) What are the factors contributing to the increased incidence of awareness?

Answer 4

● Females > males — 65% vs. 35%, respectively.

● Obese category patients > other
(underweight, normal, overweight
and morbidly obese groups of patients)
categories.

● Surgical specialty — obstetrics (highest incidence), cardiothoracic
surgery (second highest).
● Phases of anaesthesia — induction phase (more common) >
maintenance phase > emergence phase.
● Induction agents — more common with thiopentone, etomidate,
ketamine and midazolam compared with propofol.
● More common with TIVA.
● Reported more with the use of neuromuscular blockers than without
them.
● Use of neuromuscular blockers, not monitoring their effects and no
reversal of neuromuscular blockers — all increase the risk of
awareness.
● It is more likely to happen in patients with a history of awareness
under general anaesthesia in the past.
● Other over-representations for awareness in the NAP5 study included
early middle-age adults, out-of-hours operating under general
anaesthesia and junior anaesthetists managing the case.
● Drug errors including failure of anaesthetic delivery, e.g. malfunction
of the TIVA pump.
● Inadequate administration of volatile anaesthetic agent.

Question 5

e) How would you minimise the chances of awareness in
anaesthesia?

Answer 5

● Identify risk factors during the pre-assessment stage itself.
● Vigilance during anaesthesia — keep a watch on the physiological
parameters (HR, BP, RR, obvious movements, lacrimation).
● Minimise drug errors during anaesthesia.
● Supplementary doses of induction agent in cases of unexpected delay
in intubation, e.g. in a difficult intubation.
● Use of neuromuscular monitoring if neuromuscular blockers are used.
● Depth of anaesthesia monitoring if using a TIVA technique.
● Extra caution in certain surgeries prone to awareness, e.g. caesarean
section under general anaesthesia, cardiothoracic surgeries, etc.

Question 6

BJA Article

Key pts

Answer 6

Patients that experience distress during AAGA are prone to PTSD.

Evidence-based therapeutic management strategies for
AAGA-induced PTSD have been constrained
by the relatively low incidence of AAGA.

Treatment with antidepressants in combination with cognitive behavioural therapy is frequently used to treat PTSD.

Question 7

BJA article conclusions

Answer 7

Accidental awareness under general anaesthesia is associated

with ASD and PTSD in patients who experience distress,

such as paralysis and pain during the event.

However, evidence-based therapeutic management strategies for ASD and PTSD have been constrained
by the relatively low incidence of AAGA.

Thus, treatment strategies are based on extrapolations from patients with PTSD that is not associated with AAGA.

Because significant depression affects 30–50%
of patients diagnosed with PTSD,
drug treatment with antidepressants
in combination with cognitive behavioural therapy

can be especially helpful

All reports of AAGA should be taken very seriously and institutional guidelines should be in place to
follow the NAP5 awareness support pathway.

Anaesthetists should be aware of the
risk factors for AAGA and
choose their anaesthetic plan carefully,

especially regarding use of
neuromuscular blocking drugs and TIVA.

Future prevention research might study the effects of targeted psychological therapies in patients at risk for post-surgical PTSD.

Question 8

Incidence

Answer 8

. It is well established that the incidence of AAGA is significantly higher in paediatric, obstetric, and cardiac anaesthesia

heavily skewed towards women
AAGA in the UK showed that 117 out of 159 (74%) of AAGA claims were from women, and two thirds were related to obstetric care.
sex susceptibility to AAGA or possibly, a reporting bias.

Secondary analysis of 26,490 patients in the
B-Unaware trial, BAG-RECALL trial,
and MACS trial revealed that patients

with a history of AAGA were
five times more likely to experience AAGA again

The incidence of AAGA in NAP5 (∼1 out of 19,600) was remarkably lower than in previous reports

Study actively sought to report their personal experience of AAGA via a secure online portal. The authors of NAP5 argued that the occurrence of AAGA reported to NAP5 may be more relevant in clinical practice

Question 9

Risk factors

Answer 9

Obstetric patients 10-fold increase

Cardiothoracic patients and a 2.5-fold increase in

Female sex increased susceptibility as 91 out of 141 (65%) cases of AAGA involved female patients.

Obese patients were three times more likely to experience

Total intravenous anaesthesia was overrepresented in patients who experienced AAGA (18% in AAGA cases vs 8% overall)

Anaesthetic drug type,
or perhaps the use of anaesthetic drugs that are typically reserved for emergencies, increased the risk of AAGA.
Ketamine, etomidate and thiopental were used most often in the AAGA activity survey cohort

neuromuscular blocking drugs were used.

Importantly, monitoring and reversal of neuromuscular block were less frequent in those with AAGA.

Limited usage, the NAP5 investigators were not able to derive a meaningful statistical analysis between pEEG use and AAGA.

Question 10

The patient’s experience of accidental awareness during general anaesthesia

Answer 10

Spontaneous reports of AAGA did not occur routinely after the precipitating event.

Only 47 out of 141 (33%) reports were made on the day of the surgery and less than half within the first 24 h.

Many patients first reported AAGA during preparations for a subsequent procedure, as patients became understandably anxious about having general anaesthesia

postoperative checks on patients and may explain the disparity between patients’ and anaesthetists’ reports of AAGA.

NAP5 found that in 47% of AAGA cases, the recall of AAGA was described in a neutral way, involving few isolated aspects of the experience, such as auditory and tactile memory.

other 53% of the AAGA events were associated with distress. The primary causes of distress were paralysis and pain. Not surprising, all forms of distress were strongly associated with long-term psychological consequences, such as flashbacks, insomnia, fear of future surgery, and PTSD.

Question 11

Psychophysiological mechanisms of PTSD

Answer 11

The alert, non-stressed brain benefits from a top–down management system, such that the medial prefrontal cortex (mPFC) down-regulates amygdala-driven fear conditioning

stressed brain is marked by a diminished capacity of the mPFC and the hippocampus to act as checkpoints on the excitatory flow that emerges from the amygdala

mportance of the inhibitory control of the mPFC over the amygdala

Inhibition of long-term potentiation of the γ-aminobutyric acid type A receptor in the hippocampus

and other parts of the medial temporal lobe memory system – amygdala and the hippocampal region including perirhinal, entorhinal, and parahippocampal cortices –

are associated with amnesia during anaesthesia

downregulate glutamatergic and norepinephrine pathways emanating from the amygdala
ainful stimuli may further increase amygdala activity. +

Hence, the amygdalar activity surge during AAGA may lay down a permanent emotionally traumatic memory (PTSD) through excitotoxic long-term potentiation

Question 12

Psychological assessment and diagnosis

Answer 12

f panic, extreme fear, dissociation, suffocation, and fear of dying. In some, the distress persisted with long-term symptoms of post-traumatic stress. The distress of AAGA may emerge soon after the event, qualifying it as an acute stress disorder (ASD).

9 symptoms or more from the five categories of
intrusion,
negative mood,
dissociation,
avoidance, and
arousal is

required to make the diagnosis of ASD,

ASD ranges between 3 days and 1 month after exposure to the traumatic event

irritable behaviour, and angry outbursts
Sleep disturbance

Post-traumatic stress disorder is diagnosed when these symptoms last for more than 1 month after a traumatic event. Some patients do not initially present with PTSD, making the diagnosis challenging

h upsetting memories, nightmares, flashbacks, distress after traumatic reminders, and physical reactivity after exposure to trauma reminders.

(Psych SOS)
AAGA substantially increased the risk of PTSD.

Question 12

Risk Factors for post-surgical PTSD

Answer 12

poor social support;

history of PTSD;

prior mental health treatment;

dissociation related to the surgery;

perceiving that one’s life was in danger during surgery; and
intraoperative awareness.

Question 13

Management

Pharm

Answer 13

To our knowledge, there are no specific treatment guidelines for AAGA.
extrapolated from our current understanding of general PTSD.

no evidence-based psychopharmacological recommendation that prevents ASD and PTSD in patients at risk

selective serotonin reuptake inhibitors (SSRIs) can be used for both ASD and PTSD. SSRIs are recommended as first-line medication for PTSD because they can reduce symptoms of re-experiencing, avoidance, numbing, and hyperarousal

SSRIs are also effective for psychiatric disorders that frequently coexist with PTSD (e.g. depression, panic disorder, social phobia, and obsessive-compulsive disorder).

Benzodiazepines may reduce acute anxiety and help with sleep, but they have not been establised to prevent ASD or PTSD, or treat the core symptoms of PTSD.

Benzodiazepines may reduce acute anxiety and help with sleep, but they have not been establised to prevent ASD or PTSD, or treat the core symptoms of PTSD.

Question 14

Management

Answer 14

Early supportive psychotherapeutic interventions,

along with psychoeducation and
case management that encourage reliance on
inherent resilience and
good sound judgement,

can be very beneficial after acute trauma.

This is because they promote engagement in ongoing care

may also benefit from cognitive behavioural therapy with an exposure component.

Eye movement desensitisation and reprocessing, which includes a brief, interrupted exposure-based therapy, directed eye movements, along with recall and venting of traumatic memories in the setting of relaxation response elicitation, may also be helpful

Stress inoculation, imagery rehearsal, and prolonged exposure techniques may reduce PTSD-associated anxiety and avoidance symptoms.

Desipramine, fluoxetine, paroxetine, phenelzine, risperidone, sertraline, and venlafaxine were more effective than placebo for symptomatic PTSD

hus, evidence supports a choice of psychotherapeutic approaches as first-line treatments for PTSD. It is notable that treatment combining both psychotherapy and psychopharmacology was superior in the long term.

Question 15

The NAP5 awareness support pathway emphasises the importance of:

Answer 15

(i) face-to-face postoperative meeting with patients that experience AAGA;

(ii) early consultation with a psychiatrist or
psychologist and
early assessment of flashbacks,
nightmares, new level of anxiety,
and depressed mood; and

(iii) active follow-up at 2 weeks to assess
for new or ongoing needs for treatment referrals.

Question 16

Q3 — NAP6 report on anaphylaxis
a) List the four common triggers for perioperative anaphylaxis
according to the report of the National Audit Project 6 (NAP6)
from the Royal College of Anaesthetists.

Answer 16

● Antibiotics — 44%.

● Muscle relaxants — 33%.

● Chlorhexidine — 9%.

● Patent blue dye (used in breast surgeries) — 5%.**

Question 17

b) What is the estimated incidence of perioperative anaphylaxis?

Answer 17

One in 10,000.

Question 18

c) Outline the pathophysiological process of anaphylaxis.

Answer 18

● Immunologically-mediated response.

● The suspected antigen combines with immunoglobulins (IgE) causing mast cell degranulation
with the release of vasoactive mediators
(e.g. histamine, tryptase, leukotrienes, prostaglandins, etc.)
with its effects on various systems.

● Cardiovascular system —
intravascular volume redistribution causing reduced blood pressure associated with
reduced cardiac output and reduced coronary perfusion.

● Capillary leak —
causing angioedema,
laryngeal oedema, urticaria
and hypotension.

● Smooth muscle contraction in the
respiratory system and abdomen
leading to bronchospasm and
abdominal pain/cramps, respectively

Question 19

d) Describe your management of intraoperative anaphylaxis in an adult patient.

Answer 19

● Recognition of anaphylaxis from other differential diagnoses.

● Remove the trigger for anaphylaxis.

● Call for help.

● ABCDE approach,
monitoring of oxygen saturation, ECG and noninvasive
blood pressure as the minimum requirement.

● Treat life-threatening problems first,
e.g. if blood pressure is <50mmHg or cardiac arrest —
CPR in accordance with the ALS®
algorithm,
immediate adrenaline and IV crystalloid boluses.

● The drug of choice is adrenaline —
dose 500μg IM (1:1000) or
50μg boluses IV (1:10000) (boluses as needed).

● Consider an adrenaline infusion if needed —
administer in monitored settings.

● For refractory hypotension —
consider a vasopressin 2 IU bolus and repeat as necessary.

● IV crystalloid fluid boluses — 20ml/kg bolus as needed.

● Second-line drugs —
chlorphenamine 10mg IM or a slow IV in adults;
hydrocortisone — 200mg IV in adults.

● Serum mast cell tryptase levels —
as soon as possible after emergency treatment,
1-2 hours later and 24 hours later
(as a baseline).

● Other steps in management:

• 100% oxygen;
• if there are circulation problems —
  flatten the operating table with the legs up;
• if there are airway and breathing problems —
  early tracheal intubation in airway obstruction;
  head up (propped up position) to facilitate ventilation;
• if the patient has stridor —
  use an adrenaline nebuliser (400μg/kg);
• watch for the biphasic response of anaphylaxis;
• observation for 12-24 hours —
  consider transfer to the ITU if needed;
• appropriate documentation in the notes.

Question 20

e) What should be done after successful treatment of
anaphylaxis?

Answer 20

● Referral to an allergy specialist.
● Communication with the patient and family regarding the events and
actions taken must be done by the anaesthetists as well as allergy
doctors.
● Anaphylaxis education for patients — avoidance of the allergen.

Question 21

A healthy 39-year-old male is anaesthetised with a general anaesthetic for a laparoscopic cholecystectomy. As soon as the skin incision is made, it is noted that the core temperature is rising quickly. This is associated with a rise in etCO2 and an increase in heart rate.

a) What are the differential diagnoses in this condition?

Answer 21

● Malignant hyperthermia.

● Mechanical causes:
- inadequate FiO2;
- inadequate ventilation;
- problems with the anaesthetic machine or breathing circuit.

● Surgical:
- laparoscopy with gas insufflation;
- tourniquet ischaemia;
- endocrine emergencies.

● Anaesthetic:
- inadequate analgesia;
- anaphylaxis;
- cerebrovascular event.

● Patient-related:

• anaphylaxis;
• sepsis;
• neuromuscular disorders;
• phaeochromocytoma.

● Others — serotonin syndrome.

Question 22

b) What is malignant hyperthermia?

Answer 22

A progressive,
life-threatening hyperthermic reaction
occurring during general anaesthesia.

Question 23

c) Name some triggers for malignant hyperthermia.

Answer 23

● Neuromuscular blockers — suxamethonium.

● Volatile agents — halothane, enflurane, isoflurane, desflurane,
sevoflurane.

Question 24

d) What is the pathophysiology of malignant hyperthermia?

Answer 24

● Exposure of the trigger causes dysregulation of excitation —
contraction coupling (EC) in the skeletal muscle.

● Changes in ryanodine receptor (RyR) isoforms and dihydropyridine receptors (DHPRs).

● Sustained release of calcium into cytosol.

● Increased metabolic demand for ATP causes an increase in CO2 production and O2 consumption.

● A rise in CO2 stimulates the sympathetic system and the heart rate increases.

● Muscle contraction causes acceleration of heat production and
muscle rigidity progresses.

Question 25

e) How would you manage malignant hyperthermia?

Answer 25

● Early diagnosis is the key.

● Get more help.

● Stop the volatile agent,
use 100% oxygen, hyperventilate, eliminate all
triggers.

● Use activated charcoal filters in the circuit (
volatile-free machine).

● Intravenous anaesthesia.

● Dantrolene — start at 2.5mg/kg
(mixing in 60ml for each vial is time
consuming, and so ask for help by
assigning one other person the
responsibility to prepare this).

● Further doses of 1mg/kg dantrolene.

● A reaction can recur after up to 14 hours of resolution.

● Switch off warming devices.

● Active cooling measures.

● Blood samples, bladder catheter, CVP catheter.

● Treat hyperkalaemia with dextrose insulin or calcium chloride or haemofiltration (especially in rhabdomyolysis).

● Correct acidosis.

● Treat arrhythmias if any.

● Treat acute kidney injury — diuresis, alkalinise the urine.

● Treat coagulopathy.

● Monitor in intensive care unit

Question 26

f) How would you confirm the diagnosis of malignant
hyperpyrexia?

Answer 26

● In vitro contracture testing with a muscle biopsy
(European MH group guidelines, 2015).

● DNA sequencing technology.

Question 27

BJA Key pts

Answer 27

*
Enquiry about a family history of problems with anaesthesia is a mandatory part of the anaesthetic history.
*
Wherever possible, a patient suspected of being at risk of MH should have their status verified with confirmatory tests.
*
Conditions associated with variants in the RYR1 gene may also carry a risk of malignant hyperthermia.
*
Suxamethonium and potent inhalational anaesthetics are contraindicated in patients susceptible to MH.
*
Activated charcoal filters enable rapid preparation of the anaesthesia workstation for patients susceptible to MH.

Question 28

BJA MH

Answer 28

Malignant hyperthermia (MH) is a potentially lethal reaction to drugs used during general anaesthesia that occurs in genetically predisposed individuals

Another key element in reducing mortality and morbidity from MH is the identification of individuals who are genetically predisposed to develop MH (MH-susceptible) before anaesthesia so that they are not exposed to MH-triggering drugs.

n. Estimates based on clinical epidemiological data suggest a prevalence of up to 1:10,000, but those based on the prevalence in large genomic databases of genetic variants known to be associated with MH suggest that 1:1500 people may be MH-susceptible

MH-susceptible patients may have had several uneventful anaesthetics, which is why a family history of anaesthetic problems is a mandatory part of the anaesthetic history.

The Department of Anaesthesia at CUH, incorporating Intensive Care and Pain Medicine also provides support for patients with Malignant Hyperthermia (MH) and their families, and for clinicians caring for a patient with MH.

Dr. Peter Lee, Consultant Anaesthetist, is the lead in this area.

Question 29

DX

Answer 29

Diagnosis of MH susceptibility can be confirmed either through genetic testing or a muscle biopsy with in vitro contracture tests (IVCT) of the excised musc

If confirmation of the diagnosis is not in the patient’s medical records, the patient may carry correspondence or warning cards/tags issued by the diagnostic service that provided their diagnosis.

FH
amily have been tested and found susceptible to MH. We strongly recommend that the relevant diagnostic MH unit is contacted in order to verify the history.

if a relative between the family index case and the current patient has been shown not to be susceptible, the patient is not at risk

Question 30

Conditions associated with an increased risk of MH

Answer 30

1 Congenital myopathy
Only myopathies with an RYR1 or STAC3 genetic aetiology are implicated

2. Exertional rhabdomyolysis
   Some causes of rhabdomyolysis are known not to be associated with MH (e.g. CPT2 deficiency, McArdle disease)
3. Exertional heat illness
   Exclude extrinsic factors (e.g. drugs, concurrent illness, extreme environments)
4. Idiopathic hyperCKaemia
   Possible association with MH is a diagnosis of exclusion of other causes
5. Carrier of RYR1 variant of unknown significance Nonsense variants leading to a loss of function in the protein are not implicated in MH

Question 31

Perioperative management of patients with suspected MH susceptibility for elective procedures

Answer 31

If diagnosis established—proceed with trigger-free anaesthesia.

If diagnosis not established—consider the risk of proceeding with trigger-free anaesthesia or postponing the procedure until a diagnosis may be established.

The European Malignant Hyperthermia Group has recently published guideline recommendations for management of anaesthesia for a patient who is MH-susceptible

Question 32

Preoperative assessment

Answer 32

Other than establishing the risk of MH, there are no specific implications for preoperative assessment; a standard preoperative assessment should be performed for all patients who are MH-susceptible.

A thorough drug history should be taken. Patients susceptible to MH are not at increased risk of developing serotonin syndrome but it is recommended that they are not prescribed combinations of serotonergic drugs, as a perioperative serotonin syndrome may be confused with an MH reaction.

Routine investigations should be undertaken in line with national guidelines, but no extra tests are required routinely. Measuring baseline CK concentrations purely on the grounds that a patient is MH-susceptible will not change clinical management.

Question 33

Anaesthesia—generic considerations

Answer 33

Patients susceptible to MH should not be exposed to any of the triggering drugs (isoflurane, sevoflurane, desflurane, enflurane, halothane, methoxyflurane, suxamethonium).

There are no reports that indicate that MH can occur during anaesthesia when triggering drugs have been avoided

Trigger-free’ anaesthesia can be provided using regional anaesthesia or TIVA.

Advised that there is a higher risk of awareness with TIVA when compared with volatile anaesthesia.

However, if the anaesthetist is not experienced with TIVA, or does not perform TIVA on a regular basis,
it is suggested that they seek assistance from a colleague who is.

A plan is advised both to minimise the need for airway rescue should it occur, and to manage it without the use of inhalational anaesthetics or suxamethonium

Use of prophylactic dantrolene
Oral or i.v. dantrolene is not recommended for the prevention of MH in susceptible patients.

Question 34

Prepping machine

Answer 34

If short on time:

1. Remove Vaporisers
2. Flush Circuit for 90s with max flow
3. Insert ACF on both limbs
   (activated charcoal filters)
4. Change breathing circuit
   (T Piece, Circle, Reservoir bag)
   + Soda Lime

If enough time

1. Remove vaporiser
2. Change Circuit
3. Flush circuit for machine specific time

rom 5 min (Ohmeda modulus)

Question 35

Issue with machine

Answer 35

During inhalational anaesthesia,
volatile agents are adsorbed onto rubber and
plastic components of the machine, ventilator bellows, the soda lime canister, and the breathing circuit.

If adsorbed anaesthetic agent is not cleared before use of the workstation for an MH-susceptible patient,

there is a theoretical risk that an MH reaction could be triggered. It is therefore a requirement for an anaesthesia workstation to be prepared so that it delivers <5 parts per million (ppm)

Question 36

Use of activated charcoal filters

Answer 36

Use of activated charcoal filters
Activated charcoal filters have been a significant recent introduction to anaesthesia practice in relation to MH. Bench testing has demonstrated that they can reduce the concentration of volatile agent delivered from a contaminated workstation to <5 ppm within 3 min.

f they are kept in place, volatile agent concentration can be maintained <5 ppm with a fresh gas flow >1 L min−1 for at least 24 h, although recommendations are that the fresh gas flow is maintained at 3 L min−1 and the filters are changed after 12 h of use.

Question 37

Environmental exposure

Answer 37

There are no reports of MH episodes in susceptible patients from environmental exposure or healthcare workers who work in operating theatres.

. There are anaesthetists, surgeons and operating theatre staff who have MH susceptibility and who work in the operating theatre without any adverse effects. This is likely to be because triggering of MH in a susceptible individual is a time- and dose-dependent response and the environmental concentrations do not reach the threshold for triggering.

Recovery after anaesthesia
All patients can be recovered in a standard PACU. Environmental concentrations of sevoflurane measured in a PACU did not exceed 1 ppm

Question 38

Additional considerations for specific types of surgery

Obs

Answer 38

Obstetrics
When a pregnant woman is anaesthetised, so is her fetus, and triggering agents should be avoided if either is at risk of developing MH

we suggest that the risk of the fetus developing MH or significant rhabdomyolysis from the transfer of suxamethonium across the placenta is low after a standard maternal dose of 1 mg kg

he mother is known to be MH-susceptible
A detailed delivery plan should be made that minimises the possible need for an emergency Caesarean section under general anaesthesia. This includes starting epidural analgesia early in labour so that it can be rapidly extended if Caesarean section is needed

or rapid-sequence induction, neuromuscular block can be achieved with rocuronium but we recommend that sugammadex 16 mg kg−1 is drawn up and is ready to give in case early reversal is indicated. Maintenance of anaesthesia should be with a total i.v. technique. Nitrous oxide is safe to give, either during general anaesthesia or for analgesia in labour.

The father is susceptible to MH
In this case the unborn baby has a 50% risk of being susceptible to MH. Up until the time that the umbilical cord is clamped, the mother should be treated as MH-susceptible

Question 39

Emergency surgery and MH

Answer 39

For emergency surgery there is rarely time to explore a personal or family history that is suspicious of MH.

Patients in this category, along with patients with a definitive diagnosis of MH susceptibility, should be treated as at risk. In this situation, activated charcoal filters are likely to be of benefit (Fig. 1) in preparing a ‘vapour-free’ machine.

If charcoal filters are not available and there is insufficient time to prepare a workstation, oxygenation and ventilation of the lungs may be maintained on a temporary basis using a transport ventilator or even manually with a self-inflating resuscitation bag.

If general anaesthesia is required, we recommend direct supervision by a senior anaesthetist familiar with TIVA.

Question 40

Q4 — Emergency laparotomy and NELA
An 82-year-old male is listed on the emergency operating theatre list for an
urgent laparotomy. He presented with an acute abdomen and pain.

a) What is the 30-day mortality for a patient having an emergency
laparotomy? ?

Answer 40

15%.

Question 41

b) What are the common indications for an emergency
laparotomy as per the National Emergency Laparotomy Audit
(NELA) 2015?

Answer 41

● Intestinal obstruction.

● Perforation.

● Peritonitis.

● Ischaemia.

● Abdominal abscess.

● Sepsis.

● Haemorrhage.

● Colitis.

● Anastomotic leak.

● Intestinal fistula.

Question 42

c) How would you prepare this patient for anaesthesia?

Answer 42

● Risk stratification — history, examination, tests.
● Consider and treat sepsis.
● Antibiotics within the first hour of the diagnosis of sepsis.
● Fluid resuscitation.

Question 43

d) How would you anaesthetise this patient for an emergency
laparotomy?

Answer 43

● Secure the airway rapidly, minimising the risks of pulmonary
aspiration.
● Haemodynamic stability during RSI and throughout the perioperative
period.
● Optimal volume and type of fluids.
● Protective lung ventilation strategies.
● Analgesia.

Question 44

e) List the postoperative considerations in this patient.

Answer 44

● Analgesia — multimodal, regional techniques (central neuraxial, TAP
or rectus sheath).
● Intensive care — if predicted mortality is more than 10%.
● Risks of aspiration during extubation.
● Avoidance of hyperglycaemia and optimising nutritional status.

Question 45

f) As per the third National Emergency Laparotomy Audit (NELA)
2017, what are the nine key standards of care?

Answer 45

● CT scan reported before surgery.

● Risk of death documented before surgery.

● Arrival in the operating theatre within a
timescale appropriate to urgency.

● Preoperative review by a consultant surgeon and anaesthetist —
if the NELA risk of death is >5% (counted as two separate key
standards).

● Both the consultant surgeon and anaesthetist should be present in
the operating theatre if the risk is >5% (counted as two separate key
standards).

● Intensive care admission if the risk of death is >10%.

● Assessment by a geriatrician for a patient >70 years of age.

Question 46

g) What are the constituents of the Emergency Laparotomy
Pathway Quality Improvement Care (ELPQuiC) bundle

Answer 46

● Early assessment and resuscitation.

● Early antibiotics.

● Prompt diagnosis and early surgery.

● Goal-directed fluid therapy.

● Postoperative intensive care

Question 47

Q5 — Aspiration of gastric contents
A 60-year-old man is having an elective knee arthroscopy and has just
aspirated a significant amount of gastric fluid during anaesthesia. He has a supraglottic airway device in place and is breathing spontaneously. His
inspired oxygen fraction is 1.0 and the pulse oximeter shows an oxygen
saturation of 91%.

a) Describe your immediate management of this patient.
b) List the respiratory complications he could develop in the next
48 hours.

Answer 47

● Call for help.
● Rapid sequence induction with cricoid pressure.
● Secure the airway with an ETT.
● Suction the trachea through the ETT before commencing positive
pressure ventilation.
● Postoperative ITU care as prolonged periods of mechanical
ventilation may be required.
● Early bronchoscopy.
● Early chest X-ray.
● Antibiotics only if pneumonia develops.
_________________________________

● Chemical pneumonitis.
● Bacterial pneumonia causing consolidation.
● ARDS.
● Aspiration of solid particulate causes distal atelectasis and large
particles cause proximal airway obstruction and hypoxia

Question 48

c) What are the possible preoperative risk factors for
regurgitation and aspiration of gastric contents in this case?
d) What are the normal physiological mechanisms preventing
reflux?

Answer 48

Patient factors:

● Full stomach — inadequate fasting, gastrointestinal obstruction,
emergency surgery.
● Delayed gastric emptying — trauma, opioids, pregnancy and labour,
autonomic dysfunction as in DM and CRF, raised intracranial
pressure, previous GI surgery.
● Incompetent lower oesophageal sphincter — hiatus hernia, reflux
disease, morbid obesity, previous upper GI surgery.

Surgical factors:
● Laparoscopy.
● Lithotomy.
● Upper GI surgery.
Anaesthetic factors:
● Light anaesthesia.
● Difficult airway.
Device factors:
● First-generation supraglottic airways with positive pressure
ventilation.
● Long duration of surgery.

______________________

Lower oesophageal sphincter (LOS) reinforced by:
● Crura of the diaphragm.
● Acute angle between the stomach and oesophagus.
● Barrier pressure — pressure in the LOS is higher than the gastric
pressure.
Upper oesophageal sphincter formed by:
● Cricopharyngeus and thyropharyngeus.
Protective airway reflexes:
● Coughing.
● Laryngospasm.

Question 49

e) Describe the strategies available to reduce the risk and impact
of aspiration of gastric contents in any patient.
f) List the summary of recommendations from NAP4 on
aspiration.

Answer 49

● Reducing gastric volume:
- preoperative fasting;
- nasogastric aspiration;
- prokinetic premedication.
● Avoidance of general anaesthetic:
- regional anaesthesia.
● Reducing pH of gastric contents:
- antacids;
- H2 histamine antagonists;
- proton pump inhibitors.

Airway protection:
- tracheal intubation;
- second-generation supraglottic airway devices;
- prevent regurgitation;
- cricoid pressure;
- rapid sequence induction.
● Extubation:
- awake after the return of airway reflexes;
- position (lateral, head down or upright).

____________________

● Assess for aspiration risk before surgery.
● Airway management strategies should be consistent with identified
risk.
● The equipment and skills to detect and manage aspiration should be
available at all times.
● Rapid sequence induction remains the standard technique for
airway protection.
● Those applying cricoid pressure should be trained and practice
applying cricoid pressure regularly.
● In cases where tracheal intubation is not indicated, but when a
small increase in aspiration exists, second-generation supraglottic
airways should be considered.
● Strategies should be used to reduce aspiration at emergence.
● Anaesthetists should be aware of the prevention, detection and
management of blood clot aspiration.
● Active measures should be taken when a flat capnography trace
occurs when blood has been near the airway.

Question 50

Q6 — Phaeochromocytoma
A 45-year-old patient is reviewed in the preoperative assessment clinic
prior to surgery to excise a phaeochromocytoma.
a) What are the characteristic clinical features of a
phaeochromocytoma?

b) Which specific biochemical investigations might confirm the
diagnosis of a phaeochromocytoma?

Answer 50

● Pheochromocytomas are catecholamine-secreting tumours of the
adrenal medulla.

● Half of them are diagnosed on abdominal scans as an incidental
finding.

● Symptoms:
- classic triad — headache, palpitations and sweating;
- abdominal pain;
- anxiety;
- tremors;
- lethargy;
- nausea;
- visual disturbances.
● Signs:
- pallor;
- hypertension;
- weight loss;
- hyperglycaemia

Measurement of metanephrine and normetanephrine levels in plasma
(more sensitivity) or urine (more specificity).

Question 51

c) Which specific radiological investigations might confirm the
diagnosis of a phaeochromocytoma?
d) How would you pharmacologically optimise the cardiovascular
system prior to surgery?

Answer 51

● All radiological investigations need to be correlated with the clinical
picture.

● MRI abdomen — more commonly used.
● CT abdomen.

● MIBG scan.

● PET scan.

___________________________

● Arterial blood pressure control:
- preoperative alpha-blockade with
1. doxazosin or phenoxybenzamine,
to be started at least 1-2 weeks preoperatively
(prior to this if cardiomyopathy or refractory hypertension exists);

• calcium channel blockade —
  as an add-on drug if alpha-blockers
  are not sufficient, e.g. nicardipine 30mg BD
  .
  ● Heart rate control/arrhythmia control —
  use of beta-blockers, e.g.
  atenolol, metoprolol.
  Beta-blockade must be started only when
  complete alpha-blockade is established.

● Circulating volume optimisation —
measure the haematocrit to guide this.
The gradual control of arterial pressure will allow circulating
volume to return to normal over a period of time.

● Myocardial optimisation —
optimising tachyarrhythmias and
myocardial ischaemia as needed.

Question 52

e) How would you assess the adequacy of cardiovascular
optimisation preoperatively?
f) Mention the steps in the management of intraoperative
hypotension following tumour devascularisation

Answer 52

Arterial pressure readings must be <130/80mmHg consistently before the
surgery.
___________________________________

● Stop hypotensive medications.

● Optimise intravascular fluid volume.

● Noradrenaline infusion if needed — to titrate with blood pressure.

● Vasopressin bolus 0.4 U to 20 U followed by an
infusion for refractory hypotension.

Question 53

a) What are the indications for total intravenous anaesthesia
(TIVA)?
b) What are the main components of a target-controlled infusion
(TCI) system?

Answer 53

● A history of severe postoperative nausea and vomiting.

● Risk of malignant hyperthermia.

● Transfer of anaesthetised patients between different environments.

● Patient’s choice.

● Anaesthesia outside the operating theatre.

● If using a neuromuscular blocker,
this is a disadvantage for the
anaesthetised patient or surgeon.

● For airway surgeries with no endotracheal tube,
e.g. rigid
bronchoscopy with biopsy.

● Neurosurgery — for a smoother induction and awakening.
______________________________

● Interface for the user — to register the patient’s details and the target
concentrations.
● Software validated for the given drug to control the infusion.
● Communication between this software and pump hardware.

Question 54

c) What are the potential patient problems with TIVA?
d) How might each of these problems in question c be minimised?

Answer 54

● Awareness risk.
● TIVA methods are not validated in the morbidly obese population;
there is a risk of inadequate dosage (TIVA pumps are limited to a BMI
of 42 in males and 35 in females).
● Propofol-related infusion syndrome.
● Analgesia and hyperalgesia.
● Accidental overdose in the elderly and frail patients with
recommended dosages.

● Awareness risk — monitor the depth of anaesthesia, minimise
technical errors in the infusion system (e.g. watch for connection
issues with IV cannulas), understand the TIVA pharmacology.
● Morbid obesity — the use of ideal body weight in TCI pumps with a
supplemental bolus of propofol ready to administer. Use continuous
clinical assessment and depth of anaesthesia monitoring to assess the
need to administer this additional bolus.
● Propofol-related infusion syndrome — this is rare. Be vigilant for an
unexplained metabolic acidosis so that the infusion can be stopped
and the anaesthetic maintenance changed to an inhalational method.
● Analgesia and hyperalgesia — use a non-opioid-based analgesic plan
for the postoperative period; use local and regional analgesia.
● Accidental overdose in the elderly and frail patients — use slow
incremental doses to reach the intended effect site concentration
titrated to the haemodynamic and depth of anaesthesia monitor
response.

Question 55

e) What are the potential technical problems with TIVA?

Answer 55

e) What are the potential technical problems with TIVA?
● IV cannula malfunction, tubing disconnection, leakage issues — cause
a failure of delivery of TIVA.
● A risk of overdose with TIVA drugs in the absence of an antisiphon
valve and minimal dead space distal to the TIVA tubing attachment.
● Failure of pump programming with the combined loss of AC and
battery power.
● Drug errors with a remifentanil infusion.
● Forgetting to disconnect and flush the TIVA tubing at the end of the
case may cause the accidental administration of remifentanil in the
postoperative period if the cannula is flushed.

Question 56

Q8 — Obstructive sleep apnoea and STOP-BANG
A patient with obstructive sleep apnoea (OSA) but no other cardiovascular
or respiratory comorbidity is scheduled to have peripheral surgery with at
least one night stay in the hospital.

a) List all the elements of the STOP-BANG assessment for a
patient with suspected OSA.
b) How is the STOP-BANG assessment used to quantify risk?

Answer 56

● Snoring — do you snore loudly?
● Tired — do you feel tired, fatigued or sleepy during the day?
● Observed — has anyone observed you stopping breathing during your
sleep?
● Blood pressure — do you have high blood pressure or are you on
treatment for it?
● BMI — is your Body Mass Index >35kg/m2?
● Age — are you over 50 years old?
● Neck circumference — is your neck circumference greater than 40cm
(16 inches)?
● Gender — are you male?

● A score of 3 or more ‘yes’ answers — indicates a high risk of OSA
although a high proportion of false-positives will be included.
● A score of 5-8 ‘yes’ answers — identifies patients with a high
probability of moderate or severe OSA, the group most likely to
benefit from particular attention.

Question 57

c) What are the cardiovascular consequences of OSA?

Answer 57

● Arrhythmias, especially atrial fibrillation.
● Increased incidence of atherosclerotic coronary disease.
● Increased incidence of coronary events.
● Development of congestive heart failure.

Question 58

d) What steps can be taken to minimise perioperative risk in this
patient having peripheral surgery?

Answer 58

Preoperative assessment and preparation:
● Review of this patient in a dedicated high-risk anaesthetic clinic,
rather than on the morning of surgery.

● Ensure an adequate routine preoperative anaesthetic assessment
with a special focus on airway assessment.

● Encourage the patient to use CPAP regularly and to bring it into the
hospital.

● Explain the reasons for a postoperative overnight hospital admission.

Intraoperative care:
● The use of a local or regional technique may be possible as it is a
peripheral surgery.

● If using central neuraxial block, supplement with a long-acting local
anaesthetic in the peripheral nerve blocks to ensure longer-lasting
postoperative analgesia.

● General anaesthesia may be used if a local/regional block is
inadequate for surgery.

● Anticipate a difficult airway and make the appropriate preparations,
including considering the use of Optiflow THRIVE™.

● Extubate once fully awake.

Postoperative care:
● CPAP may be required to support the airway with or without
supplementary oxygen administration.

● Analgesic regimes used should cause no respiratory depression.

● Local/regional analgesia is preferred for the postoperative period.

● A prolonged period of monitoring may be required especially when
the patient is sleeping.

● Care should be provided in an appropriately staffed area that can
recognise and manage problems related to OSA.

Question 59

a) List the patient-related risk factors for postoperative nausea
and vomiting (PONV).

Answer 59

● Female gender.
● Non-smoking status.
● History of motion sickness, PONV or both.
● Low ASA physical status (ASA I-II).
● Preoperative anxiety.
● History of migraine.
● Age — in adults with increasing age, the risk of PONV decreases but
in the paediatric population, the incidence of PONV increases with
age.

Question 60

b) What are the anaesthetic-related risk factors for PONV in adult
patients?
c) What are the unwanted effects of PONV in adults?

Answer 60

● Use of volatile anaesthetics.
● Use of nitrous oxide.
● Intraoperative and/or postoperative opioid usage.
● Duration of anaesthesia.

● Delayed patient discharge.
● Increased unanticipated hospital admissions.
● Patient dissatisfaction.
● Suture dehiscence.
● Aspiration of gastric contents.
● Oesophageal rupture.

Question 61

d) Which non-pharmacological interventions have been shown to
be effective in reducing PONV in adults?
e) Briefly explain the proposed mechanisms of action of 5-HT3
antagonists such as ondansetron when used as an antiemetic

Answer 61

● Acustimulation of P6 — acupressure/acupuncture/electroacupuncture.
● Hypnosis.
● Aromatherapy

● Ondansteron is a potent, highly selective, competitive antagonist at
5-HT3 receptors.
● It lacks a dopamine receptor antagonist property.
● The mechanism of action is not clearly elucidated.
● It inhibits 5-HT3 receptors in CNS regions (area postrema, nucleus
tractus solitarius, amygdala and dorsal raphe nucleus).
● Ondansetron inhibits 5-HT3 receptors in the peripheral nervous
system also; it blocks the depolarisation of vagal afferent nerves and
myenteric neurones. This attenuates the 5-HT3 receptor-mediated
nociceptive response

Question 62

Q10 — Extubation problems
a) List the airway risk factors that may indicate a difficult
extubation.

b) List the patient factors that you can optimise prior to
extubation.

Answer 62

● Known difficult airway.
● Restricted access to the airway.

● Airway deterioration secondary to
haematoma, oedema, trauma,
bleeding, etc.

● Obstructive sleep apnoea/obesity.

● Risk of aspiration.

____________________

● Cardiovascular stability needs to be ensured.
● Respiratory factors — gas exchange and establishing a regular
breathing pattern.
● Metabolic factors — correct any metabolic/electrolyte abnormalities,
e.g. severe hypokalaemia, hypoglycaemia, etc.
● Temperature — correct hypothermia/hyperthermia.
● Neuromuscular block reversal

Question 63

c) What other factors can you optimise prior to extubation?

Answer 63

● Equipment — airway adjuncts and bite blocks, suctioning of airway.
● Location — it is safer to extubate in the operating theatre
environment if needed.
● Skilled assistance — to facilitate a sitting-up position.
● Facilitate monitoring and close observation

Question 64

d) Enumerate the strategies that you would employ to manage a
high-risk extubation.

Answer 64

● Plan — assess and optimise the airway and general risk factors.

● Optimise patient-related and other logistical factors that could
contribute to a difficult extubation.

● Perform an awake extubation if the above factors are optimised
followed by appropriate monitoring of the patient — by using
humidified O2, high-flow humidified nasal oxygen, epinephrine
nebulisation as needed.

● The use of advanced extubation techniques:
- laryngeal mask exchange technique — replace the tracheal tube
with a laryngeal mask to suppress cough and ensure smoother
emergence with non-traumatic extubation;
- use a remifentanil infusion technique — to suppress periextubation
coughing and to facilitate extubation whilst being
awake. A low-dose remifentanil infusion is maintained until
extubation;
- use an airway exchange catheter — the catheter must always be
above the carina and not >25cm inside in a typical adult patient.

● The decision to postpone extubation and monitor in an appropriate
setting until some of the high-risk factors are stabilised.

● The decision not to perform extubation and go for a tracheostomy
instead — for long-term protection of the airway.

Question 65

e) Outline the steps you would take to exchange an endotracheal
tube for a supraglottic airway device (SAD) to aid extubation.

Answer 65

● 100% oxygen supplementation to pre-oxygenate.
● Suction through the endotracheal tube.
● Aspirate stomach contents to minimise aspiration risk.
● Use a deeper plane of anaesthetic to aid extubation with minimal
coughing.
● Insertion of a supraglottic airway after extubation.
● Connect to the breathing circuit and check for ventilation.
● Check the correct seating of the LMA at the laryngeal inlet with a
fibreoptic scope to facilitate the reintubation with an Aintree catheter
if needed.

Question 66

Benfits of VL

Answer 66

That report, based on 64 studies,
provided evidence that videolaryngoscopy

improved laryngeal views,

reduced intubation difficulty scores,

and reduced failed intubations and airway trauma,

particularly among patients with a potentially difficult airway

Question 67

Factors to take into account for VL

Answer 67

1. Include the choice between single-use or reusable devices
2. range of required sizes (neonatal, paediatric, and adults from small to very large)
3. , preference for channelled vs non-channelled,

retractor-type blade or optical stylet,

conventional Macintosh shape vs non-conventional shapes
(acutely angled or J-shaped),

portability,

recording capability,

battery-enabled,

durability,

familiarity,

training,

cost, and of course,

performance-based evidence.

Question 68

Difficult intubation

Answer 68

Even if intubation is ultimately successful, blind intubation is more likely to be complicated by trauma, regurgitation, prolonged or multiple attempts, and their associated problems

If an indirect view can be achieved with less force than that required for a line-of-sight (direct) view, why do we persist in teaching and practising this method?

Question 69

DAS Extubation Guidelines

Answer 69

Plan
Assess airway and general risk factors

Airway
Deterioration
restricted access
obesity

Prepare through optimisation

Patient - CVS / Resp / Neuromuscular

Optimise
Location
Skilled help assistance
Monitoring
Equipment

Risk stratify

Low risk / At risk

Extubate

Post extubation care

Question 70

At risk algorithm

Plan

Answer 70

Plan

At risk

At Risk

Ability to oxygenate uncertain

Reintubation possibly difficulty

Is it safe to remove?

Question 71

Prepare

Answer 71

Patient factors

1. CVS
2. Resp
3. Metabolic / Temp
4. Neuromuscular

Optimise

1. Location
2. Skilled help / assistance
3. Monitoring
4. Equipment

Question 72

Perform extubation

Answer 72

Awake

Advance Tecnhiques
LMA exchange

Remi tech

Airway exchange

Not safe?

Postpone

Trachy

Question 73

Post extubation care

Answer 73

Recovery / ICU / HDU

Safe transfer

Handover / communicate

O2 and airway Mx

Obs + Monitoring

General medical and sx management

analgesia

staffing

equipment

documentation

Question 74

Awake extubation

Answer 74

Preoxygenate with 100% oxygen

Suction as appropriate

Insert a bite block (e.g. rolled gauze)

Position the patient appropriately

Antagonise neuromuscular blockade

Establish regular breathing

Ensure adequate spontaneous ventilation

Minimise head and neck movements

Wait until awake (eye opening/obeying commands)

Apply positive pressure, deflate the cuff & remove tube

Provide 100% oxygen

Check airway patency and adequacy of breathing

Continue oxygen supplementation

Question 75

Obstetric

Answer 75

Pre-induction planning and preparation
Team discussion

Rapid sequence induction
Consider facemask ventilation (Pmax 20 cmH2 O)

Laryngoscopy
(maximum 2 intubation attempts; 3rd intubation
attempt only by experienced colleague)

Verify successful tracheal intubation
and proceed
Plan extubation

if Fail
/
/
/

Declare failed intubation
Call for help
Maintain oxygenation
Supraglottic airway device (maximum 2
attempts) or facemask

Is it essential / safe to proceed with surgery?

If Fail

Declare CICO
Give 100% oxygen
Exclude laryngospasm – ensure
neuromuscular blockade
Front-of-neck access

Question 76

Algorithm 1– safe obstetric general anaesthesia

Answer 76

1. Pre-theatre preparation
   Airway assessment
   Fasting status
   Antacid prophylaxis
   Intrauterine fetal resuscitation if appropriate
2. Plan with team
   WHO safety checklist / general anaesthetic checklist
   Identify senior help, alert if appropriate
   Plan equipment for difficult / failed intubation
   Plan for / discuss: wake up or proceed with surgery (Table 1)
3. Rapid sequence induction

Check airway equipment, suction, intravenous access

Optimise position –
head up / ramping + left uterine displacement

Pre-oxygenate to FETO2

≥ 0.9 / consider nasal oxygenation

Cricoid pressure (10 N increasing to 30 N maximum)

Deliver appropriate induction / neuromuscular blocker doses

Consider facemask ventilation (Pmax 20 cmH2O)

1st intubation attempt
If poor view of larynx optimise attempt by:
* reducing / removing cricoid pressure
* external laryngeal manipulation
* repositioning head / neck
* using bougie / stylet

2nd intubation attempt
Consider:
* alternative laryngoscope
* removing cricoid pressure

Question 77

Algorithm 2 – obstetric failed tracheal intubation

Answer 77

Declare failed intubation
Theatre team to call for help
Priority is to maintain oxygenation

Supraglottic airway device
(2nd generation preferable)
Remove cricoid pressure during insertion
(maximum 2 attempts)

Facemask +/- oropharyngeal airway
Consider:
* 2-person facemask technique
* Reducing / removing cricoid pressure

Is adequate
oxygenation possible?

Follow Algorithm 3
Can’t intubate,
can’t oxygenate

Is it
essential / safe
to proceed with surgery
immediately

Question 78

Algorithm 3 – can’t intubate, can’t oxygenate

Answer 78

Declare emergency to theatre team
Call additional specialist help (ENT surgeon, intensivist)
Give 100% oxygen
Exclude laryngospasm – ensure neuromuscular blockade

Perform front-of-neck procedure

Oxygenation not restored?
Maternal ALS
Perimorten Section

Question 79

Table 1 – proceed with surgery?

Answer 79

1. Maternal condition

• No compromise *
  Mild acute compromise *
  Haemorrhage responsive to
  resuscitation
• Hypovolaemia requiring
  corrective surgery
• Critical cardiac or
  respiratory comp

Fetal condition

• No compromise * Compromise corrected with
  intrauterine resuscitation,
  pH < 7.2 but > 7.15
• Continuing fetal heart rate
  abnormality despite intrauterine
  resuscitation, pH < 7.15
  *Sustained bradycardia
• Fetal haemorrhage
  *Suspected uterine rupture

Anaesthetist
Novice / specialist

Obesity
Supermorbid / normal

Surgical factors

Complex surgery or
major haemorrhage
anticipated

Aspiration risk
Recent food / not

Alternative anaesthesia
* regional
* securing airway awake

Question 80

Proceed with surgery

Answer 80

• Maintain anaesthesia
• Maintain ventilation - consider merits of:
  ‰ controlled or spontaneous ventilation
  ‰ paralysis with rocuronium if sugammadex available
• Anticipate laryngospasm / can’t intubate, can’t
  oxygenate
• Minimise aspiration risk:
  ‰ maintain cricoid pressure until delivery (if not
  impeding ventilation)
  ‰ after delivery maintain vigilance and reapply cricoid
  pressure if signs of regurgitation
  ‰ empty stomach with gastric drain tube if using
  second-generation supraglottic airway device
  ‰ minimise fundal pressure
  ‰ administer H2 receptor blocker i.v. if not already given
• Senior obstetrician to operate
• Inform neonatal team about failed intubation
• Consider total intravenous anaesthesia