Airway Management Flashcards

A 52-year-old patient with ankylosing spondylitis presents for emergency laparotomy. Awake fibreoptic intubation is planned but fails due to excessive secretions. Direct laryngoscopy is impossible due to fixed cervical flexion. Videolaryngoscopy with a hyperangulated blade achieves a grade 1 view but tube passage is impeded. Which intervention is MOST appropriate as the next step?

Answer: Apply a stylet pre-shaped to the blade curvature and reattempt tube advancement under video guidance

With hyperangulated videolaryngoscope blades (e.g., GlideScope, C-MAC D-blade), a grade 1 view does not guarantee easy tube passage because the acute blade angle creates a mismatch with standard tube curvature. A stylet pre-bent to match the blade's angle — often 60–90° — is specifically required to navigate the tube through the acute angle into the glottis. Waking the patient or cricothyroidotomy are premature when oxygenation is maintained and a clear glottic view exists. An SGA may not provide adequate airway protection in emergency abdominal surgery and does not resolve the intubation problem.

During rapid sequence induction, rocuronium 1.2 mg/kg is administered instead of suxamethonium due to a personal or family history of malignant hyperthermia susceptibility. The patient develops unanticipated 'cannot intubate, cannot oxygenate' (CICO) crisis 4 minutes after induction. Bag-mask ventilation, two intubation attempts, and an i-gel insertion all fail to oxygenate. What is the SINGLE most important next action?

Answer: Perform emergency front-of-neck access (scalpel cricothyroidotomy)

In a declared CICO crisis, emergency front-of-neck access (eFONA) — specifically a scalpel-bougie-tube cricothyroidotomy — is the life-saving intervention and must not be delayed. While sugammadex can reverse rocuronium rapidly, its time to adequate reversal (even at 16 mg/kg) is 1–3 minutes, during which fatal hypoxia may occur. The Difficult Airway Society guidelines explicitly state that in CICO the priority is eFONA, not pharmacological reversal or further airway attempts. Sugammadex may be given concurrently but should never replace or delay eFONA once CICO is declared.

A 68-year-old with severe COPD (FEV1 28% predicted) is receiving high-flow nasal oxygen (HFNO) at 60 L/min, FiO2 1.0 during an awake fibreoptic intubation for elective thoracic surgery. SpO2 is 94% throughout the procedure. Immediately after the tube is secured and HFNO discontinued, SpO2 falls to 82% despite ventilation with FiO2 1.0 and PEEP 8 cmH2O. What is the MOST likely explanation?

Answer: Absorption atelectasis from prolonged 100% oxygen exposure compounded by airway closure at low lung volumes

Patients with severe COPD have markedly elevated closing volumes, meaning small airways close at functional residual capacity (FRC) during tidal breathing. Prolonged pre-oxygenation with 100% oxygen causes nitrogen washout; when airways close, the trapped 100% oxygen is rapidly absorbed (absorption atelectasis), causing acute shunt. This effect is compounded at induction by loss of consciousness and supine positioning, which further reduces FRC. The temporal pattern — saturation maintained during HFNO but immediately crashing after intubation — is the hallmark. Endobronchial intubation is possible but would more likely produce unilateral absent breath sounds and asymmetric chest rise, detectable on auscultation. Loss of intrinsic PEEP is more relevant to haemodynamic compromise than acute desaturation of this magnitude. Oxygen-induced hypercapnia does not cause this acute desaturation pattern.

You are managing a patient on veno-venous ECMO (VV-ECMO) for severe ARDS who requires airway exchange due to a cuffed tube with a ruptured cuff. Current ventilator settings: Vt 3 ml/kg IBW, PEEP 14, FiO2 0.8. ECMO flow 4.5 L/min, SpO2 88% (acceptable per team). What is the MOST important airway exchange consideration unique to this patient?

Answer: Increase ECMO sweep gas FiO2 to 1.0 and flow to maximum before the exchange to maximise oxygen reserve

In VV-ECMO for severe ARDS, the ECMO circuit is providing a substantial portion of oxygenation and CO2 removal. Unlike the native lung, the ECMO circuit's oxygen delivery can be transiently maximised by increasing sweep gas FiO2 to 1.0 and pump flow to maximum — this creates the greatest oxygen reserve during the brief apnoeic period of tube exchange and is the intervention unique to ECMO management. Using an AEC with insufflation is correct technique but risks barotrauma in stiff ARDS lungs with high PEEP, particularly with flow rates of 15 L/min which can generate significant pressure against a partially obstructed circuit. Maintaining PEEP is important but secondary to ensuring maximum systemic oxygenation via ECMO. Avoiding paralysis is incorrect — complete relaxation ensures the exchange is smooth and minimises coughing, which could dislodge the AEC or cause haemodynamic compromise.

A patient undergoing elective cervical spine surgery in the prone position suffers loss of airway integrity (tube displacement) 90 minutes into the procedure. The surgical table cannot be rapidly repositioned supine. Mask ventilation in the prone position achieves SpO2 of 95%. Which statement regarding prone airway management is MOST accurate?

Answer: Orotracheal reintubation in the prone position is feasible using videolaryngoscopy and represents an acceptable rescue strategy

Prone intubation, while rarely required, is a recognised and feasible rescue technique when airway loss occurs during prone surgery. Videolaryngoscopy is particularly suited to prone intubation because the operator can stand at the head of the table and the screen view is independent of operator position relative to the patient's mouth. Published case series and simulation data support its feasibility. Supraglottic airways (specifically second-generation devices like the i-gel or ProSeal LMA) have been used successfully in the prone position and are not absolutely contraindicated — they provide airway protection with an oesophageal drain. Bag-mask ventilation in the prone position does work (and arguably benefits from improved FRC), but the 90% figure is not evidence-based and continued BMV delays definitive airway control. Cricothyroidotomy is technically more complex in the prone position due to anatomical access and is a last resort, not first-line.

A 44-year-old with hereditary haemorrhagic telangiectasia (HHT/Osler-Weber-Rendu syndrome) requires general anaesthesia. She has a known pulmonary arteriovenous malformation (PAVM) in the right lower lobe. Which airway management consideration is MOST specifically relevant to her PAVM?

Answer: Use meticulous bubble-free IV technique and avoid nitrous oxide to prevent paradoxical embolisation through the PAVM

A pulmonary AVM creates a direct right-to-left shunt bypassing the pulmonary capillary filter. This means venous air emboli, thromboemboli, or paradoxical emboli of any kind can pass directly into the systemic circulation, causing stroke or coronary air embolism. Meticulous bubble-free IV technique (using air filters, avoiding air flushing of lines) is critically important, and nitrous oxide — which rapidly diffuses into and expands gas emboli — is specifically contraindicated. This is the most relevant airway/anaesthetic consideration for a patient with PAVM. Nasal intubation risk from telangiectasias is real and relevant, but not specific to the PAVM itself. Positive-pressure ventilation is not specifically contraindicated with PAVM. ETT tip positioning does not meaningfully alter PAVM ventilation/perfusion ratios.