Introduction: Obstructive sleep apnoea (OSA) is associated with increased perioperative morbidity and mortality. Patients at risk of OSA as determined by pre-anaesthesia screening based on the American Society of Anesthesiologists checklist were divided into 2 groups for comparison: (i) those who proceeded to elective surgery under a risk management protocol without undergoing formal polysomnography preoperatively and; (ii) those who underwent polysomnography and any subsequent OSA treatment as required before elective surgery. We hypothesised that it is clinically safe and acceptable for patients identified on screening as OSA at-risk to proceed for elective surgery without delay for polysomnography, with no increase in postoperative complications if managed on a perioperative risk reduction protocol.
Materials and methods: A retrospective review of patients presenting to the preanaesthesia clinic over an 18-month period and identified to be OSA at-risk on screening checklist was conducted (n = 463). The incidence of postoperative complications for each category of OSA severity (mild-moderate and severe) in the 2 study groups was compared.
Results: There was no statistically significant difference in the incidence of cardiac (3.3% vs 2.3%), respiratory (14.3% vs 12.5%), and neurologic complications (0.6% vs 0%) between the screening-only and polysomnography-confirmed OSA groups respectively (P >0.05). There was good agreement of the OSA risk that is identified by screening checklist with OSA severity as determined on formal polysomnography (kappa coefficient = 0.953).
Conclusion: Previously undiagnosed OSA is common in the presurgical population. In our study, there was no significant increase in postoperative complications in patients managed on the OSA risk management protocol. With this protocol, it is clinically safe to proceed with elective surgery without delay for formal polysomnography confirmation.