Airway management in critically ill patients, who have exhausted their physiologic reserve and are under undue stress, can have disastrous consequences. Further complicating matters, the critically ill often require airway management in settings outside of the intensive care unit (ICU) where experienced providers and appropriate equipment and medications may not be readily available. Hypoxia, hemodynamic instability, elevated intracranial pressure, emesis, gastrointestinal bleeding, and postextubation laryngeal edema are common conditions that make airway management challenging in the critically ill. Not surprisingly, complications during airway management account for a significant percentage of adverse events in the ICU.¹,²,³ The medical complexity of patients in the ICU is an important contributing factor to airwayrelated complications. Therefore, an understanding of the individual patient’s physiologic derangements can help formulate an airway management plan to avoid adverse events.

Although the majority of critically ill patients undergo tracheal intubation in the ICU setting, airway management may also occur in the inpatient wards or elsewhere in the hospital, such as the radiology suite or special procedures laboratories. In the ICU, equipment such as infusion pumps, dialysis machines and mechanical ventilators limit access to the patient. Air mattresses used to prevent pressure sores in ICU patients can make proper positioning difficult as well. Outside of the ICU, airway equipment, appropriate medications, and experienced personnel may not be readily available. Medical emergency teams staffed by expert personnel who are appropriately equipped and available 24 hours per day may help to overcome such challenges.⁴

Emergency tracheal intubation outside of the operating room (OR) is associated with a decreased complication rate when performed in the presence of an attending physician, rather than by unsupervised trainees.¹,⁵ Complications during airway management in the critically ill also can be minimized by having the proper equipment and medications necessary to manage the difficult airway. Unfortunately, only 50% of ICUs in the United States have a difficult airway cart and fewer than 5% have the equipment suggested in the American Society of Anesthesiology Practice Guidelines.⁶,⁷ At the University of Pittsburgh Medical Center, we have standardized the approach to airway management in the critically ill by creating a portable airway bag that contains the medications and equipment necessary to manage both routine and difficult airways (Table 49-1).⁸ The contents of the airway bag are uniform, such that any desired piece of equipment can be quickly located (Fig. 49-1). The standardized airway bag is stored in each ICU, is brought to all medical emergency calls within the hospital, and is restocked by the hospital central supply department after each use.

Predicting the difficult airway allows for preparation of the proper equipment and resources to ensure successful intubation on the first attempt. Unfortunately, many of the traditionally described predictors of difficult intubation have not been validated in the critically ill.⁹ In fact, Mallampati classification, thyromental distance, and neck mobility cannot be assessed in many patients undergoing emergency intubation due to lack of patient cooperation, altered mental status, or cervical spine immobilization.¹⁰ However, several conditions commonly encountered in the critically ill will likely cause difficulties during airway
management. Upper airway obstruction from a hematoma, abscess, angioedema, epiglottitis, or postextubation laryngeal edema can hinder mask ventilation, intubation, and the use of an extraglottic rescue device. The presence of blood, secretions, or vomitus in the airway can obscure laryngoscopic view. In addition, increased resistance from reactive airways; poor lung compliance in patients with significant airspace disease; and reduced thoracoabdominal compliance from ascites, abdominal compartment syndrome, or flail chest can make the use of mask ventilation or extraglottic rescue devices difficult. Thus, a patient who would be predicted to have a routine airway for elective
intubation can pose a challenge when critically ill, and it would be wise to over-prepare, rather than under-prepare during airway management in the critically ill.