The predictive value of obstructive sleep apnoea severity on clinical outcomes following maxillomandibular advancement surgery

We aimed to evaluate whether the severity of preoperative obstructive sleep apnoea (OSA) has potential predictive value for the clinician assessing patients referred for maxillomandibular advancment surgery. We performed a retrospective analysis of consecutive patients who underwent maxillofacial operations for OSA at our institution. We stratified them into 2 groups according to apnoea/hypopnoea index (AHI) scores calculated from a preoperative sleep study: mild-moderate OSA (AHI less than 30) and severe OSA (AHI 30 and above). Both groups were matched for baseline demographic and clinical characteristics. We compared postoperative scores for the AHI and Epworth sleepiness scale (ESS), and lowest recorded oxygen saturation between groups. We identified 51 patients of whom 39 had complete data available for inclusion in our analysis. We found no statistically significant difference in the postoperative AHI scores between the two groups. The reduction in the mean ESS after operation was greater in the severe group than in the mild-moderate group (mean (SD) ESS 4 (3) compared with 9 (6), p < 0.05). There were high rates of surgical success (postoperative AHI less than 15) in both groups, and results were comparable (mild-moderate group 82%, severe group 86%). The preoperative AHI does not appear to be a good predictor of surgical success after maxillomandibular advancement surgery. Patients with severe OSA postoperatively demonstrated a greater improvement in their subjective symptoms, when compared to subjects with mild-moderate OSA.