Background: Obstructive sleep apnea (OSA) has been identified as a risk factor for perioperative complications in various patient cohorts1. However, there is a lack of data on the prevalence of OSA and its association with outcomes in patients undergoing hysterectomies, one of the most frequently performed surgeries among women2.
We analyzed the impact of OSA on perioperative outcomes among patients undergoing hysterectomy. Analogous to other surgeries, we hypothesized that OSA in patients undergoing hysterectomy would be associated with an increased risk of perioperative complications as well as with increased cost of hospitalization and length of stay.

Material and Methods: We extracted a sample of patients who underwent a hysterectomy between 2006 and 2014 from a large nationwide administrative database (Premier Perspective Database, Premier Inc., Charlotte, North Carolina). Among this patient sample we identified OSA-patients by using ICD-9 CM codes and subsequently compared them for perioperative outcomes with those patients who had no diagnosis of OSA. These perioperative outcomes included opioid utilization, cost of hospitalization and length of stay, need for blood transfusion, ICU admission as well as cardiac, central-nervous, gastrointestinal, genitourinary, renal, respiratory and thromboembolic complications. Multilevel multivariable models were fitted to determine associations between OSA status and outcomes. Odds ratios (OR) and 95% confidence intervals (CI) are reported. Since only de-identified data was used, this study was exempt from patient consent by the Institutional Review Boards of the Hospital for Special Surgery and Icahn School of Medicine at Mount Sinai.

Results: Of N = 459,508 patients undergoing hysterectomy, n = 11936 (2.6%) had a diagnosis code for OSA listed. On average, OSA-patients were older (52.3 ± 11.4 years vs. 48.4 ± 12.1 years; p < 0.0001) and had a higher Deyo-Charlson comorbidity score (1.13 ± 1.79 vs.0.55 ± 1.49; p < 0.0001) than non-OSA patients. When controlling for relevant covariates, OSA status was associated with increased cost of hospitalization (+6.24%; p < 0.0001) and longer length of stay (+2.58%; p < 0.0001) compared to patients without OSA. In addition, OSA-patients had higher opioid utilization than non-OSA patients (+1.24%; p = 0.04). A similar pattern was seen for complications: OSA (compared to non-OSA) was associated with substantially higher odds for ICU admission (OR 2.28; CI 1.77 – 2.94) and renal (OR 1.98; CI 1.70 – 2.31) or respiratory complications (OR 3.25; CI 2.97 – 3.56).

Conclusion: In this cohort of patients undergoing hysterectomies, OSA prevalence was low but associated with substantially (up to >300%) increased risk of complications. Further research is needed to assess currently used perioperative care strategies for OSA patients undergoing hysterectomies, with the goal to improve outcomes.

References:
1.	Opperer M, Cozowicz C, Bugada D, Mokhlesi B, Kaw R, Auckley D, Chung F, Memtsoudis SG. Does Obstructive Sleep Apnea Influence Perioperative Outcome? A Qualitative Systematic Review for the Society of Anesthesia and Sleep Medicine Task Force on Preoperative Preparation of Patients with Sleep-Disordered Breathing. Anesthesia & Analgesia 2016;122:1321-34.
2.	Wright JD, Herzog TJ, Tsui J, Ananth CV, Lewin SN, Lu Y-S, Neugut AI, Hershman DL. Nationwide Trends in the Performance of Inpatient Hysterectomy in the United States. Obstetrics and gynecology 2013;122:233-41.

Obstructive sleep apnea increases the odds for perioperative complications in patients undergoing hysterectomy