Association of Obstructive Sleep Apnea With Difficult Intubation: Prospective Multicenter Observational Cohort Study

Abstract

BACKGROUND: Obstructive sleep apnea (OSA) has been found to be associated with difficult airway, although there is a paucity of prospective studies investigating thresholds of OSA severity with difficult airway outcomes. The aim of this study was to examine the association between OSA and difficult intubation or difficult mask ventilation. We also explored the utility of the Snoring, Tiredness, Observed apnea, high blood Pressure, Body mass index, Age, Neck circumference, and Gender (STOP-Bang) score for difficult airway prediction. METHODS: The Postoperative Vascular Complications in Unrecognized Obstructive Sleep Apnea (POSA) trial was an international prospective cohort study of surgical patients 45 years or older with one or more cardiac risk factor presenting for noncardiac surgery, with planned secondary analyses of difficult airway outcomes. Multivariable logistic regression analyses tested associations between OSA severity and predictors of difficult airway with difficult intubation or difficult mask ventilation. Overall, 869 patients without prior diagnosis of OSA were screened for OSA risk with the STOP-Bang tool, underwent preoperative sleep study, and had routine perioperative care, including general anesthesia with tracheal intubation. The primary outcome analyzed was difficult intubation, and the secondary outcome was difficult mask ventilation. RESULTS: Based on the sleep studies, 287 (33%), 324 (37%), 169 (20%), and 89 (10%) of the 869 patients had no, mild, moderate, and severe OSA, respectively. One hundred and seventy-two (20%) had a STOP-Bang score of 0–2 (low risk), 483 (55%) had a STOP-Bang score of 3–4 (intermediate risk), and 214 (25%) had a STOP-Bang score 5–8 (high risk). The incidence of difficult intubation was 6.7% (58 of 869), and difficult mask ventilation was 3.7% (32 of 869). Multivariable logistic regression demonstrated that moderate OSA (odds ratio [OR] = 3.26 [95% confidence interval {CI}, 1.37-8.38], adjusted P = .010) and severe OSA (OR = 4.05 [95% CI, 1.51-11.36], adjusted P = .006) but not mild OSA were independently associated with difficult intubation compared to patients without OSA. Relative to scores of 0–2, STOP-Bang scores of 3–4 and 5–8 were associated with increased odds of difficult intubation (OR = 3.01 [95% CI, 1.13-10.40, adjusted P = .046] and 4.38 [95% CI, 1.46-16.36, adjusted P = .014]), respectively. OSA was not associated with difficult mask ventilation, and only increasing neck circumference was found to be associated (adjusted P = .002). CONCLUSIONS: Moderate and severe OSA were associated with difficult intubation, and increasing neck circumference was associated with difficult mask ventilation. A higher STOP-Bang score of 3 or more may be associated with difficult intubation versus STOP-Bang score of 0–2. Anesthesiologists should be vigilant for difficult intubation when managing patients suspected or diagnosed with OSA.

Obstructive sleep apnea and perioperative management of the difficult airway

“…A recent large prospective international cohort study by Seet et al on 869 patients with unrecognized OSA reported that moderate (defined as AHI 15 to 30 events/h) and severe OSA (defined as AHI > 30 events/h) were independently associated with DI. 40 Multivariable logistic regression analysis showed that the incidence of DI was 3-fold higher in moderate OSA [odds ratio (OR): 3.26, 95% confidence interval (CI): 1.37-8.38], and 4-fold higher in severe OSA (OR: 4.05, 95% CI: 1.51-11.36). In the same study, a comparable relationship was demonstrated in patients with higher STOP-Bang scores, where the incidence of DI was 3-fold in patients with STOP-Bang scores of 3-4 (OR: 3.01, 95% CI: 1.13-10.40, P = 0.046) and 4-fold in patients with scores of 5 to 8 (OR: 4.38, 95% CI: 1.46-16.36).…”

“…7 One recent large prospective international cohort study demonstrated that moderate to severe OSA and STOP-Bang scores of ≥ 3 were independently associated with DI. 40 The Society of Anesthesia and Sleep Medicine recommends that patients with OSA and patients at risk of OSA should be considered at risk of DMV and/or DI. 7 Therefore, anesthesia providers should be vigilant, and adequate preparations should be made for these vulnerable patients to avoid adverse events.…”

Ambulatory surgical patients and sleep apnea

“…28 Physical examination findings common in patients with OSA include obesity, increased fat deposition in the neck and pharynx, an enlarged tongue, enhanced tonsils, and a small upper airway diameter. 1,29 This can result in difficult mask ventilation and poor visualization of the vocal cords during direct or video laryngoscopy. This can predispose patients to perioperative airway trauma and laryngeal injury leading to edema, more rapid oxygen desaturation, and aspiration.…”

Patients with sleep-disordered breathing for bariatric surgery

“…Patients with OSA and obesity can have more collapsible upper airways and reduced functional residual capacity (FRC) that predispose them to rapid desaturation, even after short periods of apnea or hypoventilation. [ 42 43 ] OSA has been found to be a risk factor for difficult tracheal intubation (DI)[ 43 ] and difficult mask ventilation (DMV). [ 12 44 45 46 47 ] Furthermore, the Fourth National Audit Project (NAP4), found that patients with obesity (BMI 30–35 kg/m 2 ) and morbid obesity (BMI >35 kg/m 2 ) had twice and four times as many serious airway complications as patients without obesity, respectively.…”