On a Saturday morning, a 42-year-old male presents to the operating room for an urgent cystoscopy to remove a high ureteric stone. He is a smoker and has no known allergies. He has been taking subcutaneous hydromorphone for renal colic for several days as an inpatient, with little relief. He has had numerous uneventful previous cystoscopy and extracorporeal shock wave lithotripsy (ESWL) procedures in the past for nephrolithiasis. His last general anesthetic for a cystoscopy 6 months ago was completed uneventfully after the insertion of a LMA-Classic #5. He has been appropriately fasted for 8 hours when he arrives in the operating room.
The patient's cardiovascular and respiratory examination is unremarkable, his vital signs are stable and he is afebrile. The urology team does not feel that the patient has urosepsis at this time. His BMI is 27.3 kg·m−2. His airway exam is normal with no predictors of difficulties in bag-mask-ventilation (BMV), use of extraglottic devices (EGDs), tracheal intubation, or surgical airway.
He has a #18-gauge IV catheter in situ in his left forearm. Following denitrogenation, general anesthesia is induced with midazolam 1 mg IV, fentanyl 50 mcg IV, and propofol 250 mg IV. Immediately after propofol administration and as the patient loses consciousness, he complains of pain at the IV site, and bile-colored fluid leaks around the face mask. Projectile vomitus occurs when the face mask is removed. After suctioning the oropharynx in Trendelenburg position, oxygen saturation rapidly decreases to 80%, and there is an audible wheeze. Swelling is noted at the IV site and the gravity feed IV is no longer dripping.
Aspiration of gastric contents is still an important cause of morbidity and mortality associated with airway management. Aspiration was the most common cause of death in anesthesia cases reported to the Fourth National Audit Project—Major complications of airway management in the UK: Results of the Fourth National Audit Project of the Royal College of Anaesthetists and the Difficult Airway Society (NAP4). This report, published in 2011, illustrated that aspiration is not simply a historical anesthesia complication.1 Events in which death occurred were associated with significant hypoxemia and brain damage following aspiration.
The incidence of aspiration during anesthesia has been widely estimated, and this is reviewed in Chapter 5. One in five of all NAP4 anesthesia reports described aspiration of gastric contents as a primary or secondary event (17% and 5% respectively). In addition, many aspiration event survivors had prolonged intensive care stays. Common themes were incomplete assessment of aspiration risk and failure to alter the anesthetic technique when aspiration risk was present.
Great care is taken to discuss pre-induction preparation for prevention of aspiration in airway algorithms, but interestingly, little attention is given to management of ongoing aspiration in the setting of a “cannot intubate, cannot oxygenate” (CICO) difficult airway, and ...