Published in Br J Anaesth 2014 Nov 27
Authors: De Jong A et al.
Obesity and critical illness are dangerous in combination.
Obesity affects all components of airway management, including oxygenation, bag-valve-mask ventilation, and choice of pharmacologic agents, intubation surgical airway, and rescue devices. In a prospective, multicenter, observational study, researchers in France assessed the incidence of difficult intubation and its associated complications in obese patients in both the intensive care unit (ICU) and operating room (OR).
Of 1400 consecutive patients intubated in the ICU and 11,035 intubated in the OR, 282 (20%) and 2103 (19%), respectively, were obese. In both groups, anesthesiologists performed most intubations. Rates of obstructive sleep apnea, respiratory failure, and Mallampati class III and IV airways were higher in the ICU cohort, while use of difficult airway adjuncts (video laryngoscopy and bougies) was lower. Difficult intubation (defined as 3 or more intubation attempts, intubation duration >10 minutes, or both) was twice as common in the ICU group as the OR group (16.3% vs. 8.2%). In both groups, risk factors for difficult intubation were Mallampati score III/IV, obstructive sleep apnea, and reduced mobility of the cervical spine. Severe life-threatening complications occurred in 41% of ICU intubations versus 2% of OR intubations; most were related to severe hypoxemia or hypotension.
Although both groups included obese patients, their severity of illness differed and limits direct comparisons. In addition, lower use of video laryngoscopy may have contributed to higher intubation difficulty in the ICU cohort. In critically ill obese patients, airway managers should focus on robust preoxygenation, shock-sensitive pharmacologic dosing, and early use of difficult airway adjuncts such as video laryngoscopy.