Anaesthesiologists' role in diagnostic drug-induced sleep endoscopy and subsequent management strategy planning in obstructive sleep apnoea syndrome

Abstract

Background and Aims: Obstructive sleep apnoea is characterised by repetitive partial or complete obstruction of the upper airway during sleep, leading to the reduction or cessation of airflow despite ongoing respiratory effort. Obesity, dyslipidaemia, hypertension, diabetes mellitus and cardiac arrhythmias are common co-existing comorbidities, placing patients at high risk for anaesthesia should they present for incidental or corrective surgeries. These patients are sensitive to opioids, induction and inhalational anaesthetics. Drug-induced sleep endoscopy (DISE) helps in assessing the exact site of airway obstruction and gives valuable inputs for surgical correction. The procedure includes stage-wise induction of sleep and airway visualisation during pharmacologically-induced sleep. Patients and Methods: Thirty patients, aged between 20 and 60 years, with a history of snoring and night arousals, were selected for DISE after taking informed consent. Intravenous propofol 0.5 mg/kg loading dose, followed by a titrated infusion of up to 50 μg/kg/min, was given throughout the procedure. The lowest value of oxygen saturation (SpO2), apnoeic episodes, total propofol used and DISE findings were documented. The airway was managed after the procedure till the patients regained full consciousness. Results: Lower SpO2 readings were observed in patients with complete collapse at the tongue base and in patients with floppy epiglottis. Conclusion: DISE is a dynamic, safe, easy-to-perform procedure that visualises the precise site of airway obstruction and guides in the planning of surgical correction thereafter. DISE findings provide valuable information for titrating doses of anaesthetic agents for incidental surgeries and perioperative management. However, the fine balance between identifying the obstruction and preventing desaturation is often challenging.