Management Plan to Reduce Risks in Perioperative Care of Patients with Obstructive Sleep Apnoea Averts the Need for Presurgical Polysomnography

Abstract

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 pre anaesthesia 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. Key words: Postoperative complications, Preoperative screening, Risk management, Undiagnosed OSA

Pulmonary assessment and optimization for older surgical patients

“…Retrospective data suggest that the initiation of OSA treatment before surgery is associated with decreased risk for postoperative complications 57,58. However, at least 1 randomized controlled trial of patients screened as high-risk for OSA found that preoperative initiation of positive airway pressure (PAP) therapy before surgery provided no benefit when added to a program of perioperative measures designed to reduce OSA-related risk 59. Consistent with these data, the Society of Anesthesia and Sleep Medicine only recommends evaluation by sleep medicine before elective procedures for patients at high risk for undiagnosed OSA (eg, STOP-BANG ≥5) who also have uncontrolled comorbidities, hypoxemia, or elevated serum bicarbonate level (indicative of possible obesity hypoventilation syndrome) 60.…”

“…As described earlier, at least 1 study found that preoperative evaluation and treatment of OSA was not necessary when a risk reduction protocol was utilized for patients suspected to have sleep apnea. Elements of that protocol included multimodal, opioid-sparing analgesic regimens; avoiding long-acting NMB; extubating only after fully conscious; elevation of the head of the bed during recovery; and continuous respiratory monitoring (pulse oximetry and/or capnography) during and after surgery 59. Guidelines from the Society of Anesthesia and Sleep Medicine also recommend regional anesthesia over general anesthesia, avoidance of IV benzodiazepines, preparations for difficult airway management, and anticipation of varied opioid responses 83…”