PURPOSE: Anesthetics, analgesics and surgery may have a tremendous impact on the sleep of patients in the postoperative period. The objective of this study is to explore the factors that affect postoperative Apnea-Hypopnea Index (AHI).
METHODS: Following REB approval, all preoperative patients giving consent were invited to undergo polysomnography (PSG) with a portable device (Embletta x100) preoperatively at home; on the first, and third postoperative night in the hospital or at home. The PSG recordings were scored by a certified PSG technologist. Then the AHI on different perioperative nights were treated as repeated measurements and analyzed with mixed model.
RESULTS: A total of 202 patients completed the study, 93 males and 109 females. Age was 59 ± 11, and BMI 31± 7 . 161 patients had major surgeries, 23 intermediate surgeries and 18 minor surgeries, with 94 under general and 108 under regional anesthesia. ASA physical status: I-3 (1.5%), II-98(48.5%), III-100 (49.5%) and IV-1 (0.5%).The total dose of opioids used in first 3 postoperative days was equivalent to 61± 100 mg morphine intravenously. AHI on preoperative, postoperative night 1, and night 3 was 19± 20, 29± 30, and 37± 35 respectively. Compared to preoperative value, AHI was significantly increased on postoperative night 1 and night 3. The severity of preoperative OSA and male gender were the two significant factors predicting postoperative AHI. Compared to no OSA, the effect size of mild OSA , moderate OSA and severe OSA on postoperative AHI was 7.7 (1.5), 20.5 (1.5) and 48.8 (1.8) [ beta estimate (standard error)]. Age>50, BMI>35, ASA physical status, the dose of opioids , type of anesthesia or surgery were not found significant.
CONCLUSION: Compared to preoperative value, AHI was significantly increased on postoperative night 1 and night 3, more on night 3 than night 1. The severity of preoperative OSA and male gender were the significant factors predicting the postoperative AHI.
CLINICAL IMPLICATIONS: The male patients with moderate and severe OSA are more likely to experience an exacerbation after surgery.
DISCLOSURE: Frances Chung, No Financial Disclosure Information; No Product/Research Disclosure Information