A 60-year-old man with chronic obstructive lung disease, limited exercise tolerance, and new-onset pneumonia required tracheal intubation because of hypoxemic respiratory failure. Optimal positioning for direct laryngoscopy (DL) performed by an experienced practitioner using a Macintosh 3 blade yielded a Cormack/Lehane (C/L) 3 view, requiring the use of an Eschmann tracheal tube introducer (ETTI). After 6 days of assisted ventilation, he had now been weaned to an FiO2 of 0.4, positive end-expiratory pressure of 5 cm H2O, and pressure support of 5 cm H2O. The pulmonary infiltrates were much improved. His respiratory rate was 24 breaths per minute. A cuff-leak test was performed.
28.2.1 What Is a High-Risk Extubation?
In anesthesia, and most likely in critical and emergency care, adverse respiratory events are more frequently associated with extubation than intubation.1,2 Nonetheless, much less attention has been paid to the management of extubation. A stratification of risk associated with extubation has been proposed,3 and although unsupported by controlled, randomized clinical trials, the need for an extubation strategy has been advocated by expert panels.4,5 The extubation of patients, who were easily intubated and in whom no intervening event has occurred to jeopardize their airways, can be regarded as "low-risk extubations." Those who were easily intubated but who are at greater risk of requiring reintubation (due to hypoxemia, hypercapnia, inadequate clearance of secretions, inability to protect their airway, or airway obstruction) are "intermediate-risk extubations. " Those in whom airway management is likely to be challenging or complex if reintubation is required represent "high-risk extubations." The last group includes:
Patients with a difficult tracheal intubation (failure to visualize their glottis —C/L ≥ 3—requiring multiple attempts or alternative techniques).
Those with interval complications (airway edema, extrinsic compression, glottic injuries).
Those with clinical conditions associated with difficult ventilation and/or intubation. This latter group would include, for example, patients with paradoxical vocal cord motion, morbid obesity, obstructive sleep apnea, airway surgery, maxillofacial surgery (particularly when it involves inter-maxillary fixation), deep-neck infections, cervical surgery, angioedema, or prolonged intubation.3
For most patients, the risk of requiring reintubation is low. The results of three studies involving nearly 50,000 patients presenting for a wide variety of surgical procedures indicated that only 0.09% to 0.19% required reintubation.6-8 Certain surgical procedures such as panendoscopy and a variety of head and neck operations are associated with a risk of required reintubation approximately 10 times higher (1%-3%).9-13 Patients in critical care units often have limited physiologic reserve, altered secretions, or an impaired capacity to protect their airways. In this group of patients, required reintubation is substantially higher still.14-16
When patients require emergency reintubation, the airway practitioner may have limited clinical information, equipment, supportive personnel, or preparation time. Furthermore, the patient may be hemodynamically unstable with associated airway obstruction, hypoxemia, or acidosis. There may be a reluctance to administer paralytics ...