Patients underwent a sleep study preoperatively during which the apnea index and minimum oxygen saturation were determined.
Patients at significant airway risk:
(1) apnea index >= 70 (sum of apneic and hyponeic episodes per hour of sleep)
(2) minimum oxygen saturation < 80% preoperatively on room air
(3) unfavorable upper airway anatomy
Patients with unfavorable upper airway anatomy:
(1) short, thick neck
(2) relative macroglossia
(3) redundant soft palate and oropharyngeal soft tissue
(4) inferiorly placed hyoid bone
(5) history of difficult intubation
Management of a patient at significant airway risk:
(1) undergo awake oral or oronasal intubation, with direct fiberoptic visualization if needed
(2) avoid use of narcotics as much as possible and use minimal doses
(3) delay extubation postoperatively until the patient is fully alert, which may involve overnight intubation with monitoring in the ICU
A patient should have cardiac monitoring if preoperative assessment shows one or both of the following:
(1) cardiac arrhythmias
(2) minimum oxygen saturation < 60% during the sleep study
The authors note that criteria are set at high sensitivity and low specificity, favoring patient inclusion. The ROC curves for the apnea index and minimum oxygen saturation in Figure 1 and 2 are pretty poor. However, since the protocol is relatively benign and the complications potentially severe, they felt that it was reasonable.
