Occurrence of rapid eye movement sleep deprivation after surgery under regional anesthesia.

ABSTRACT

BACKGROUND: Sleep disturbances after general surgery have been described. In this study, we assessed rapid eye movement (REM) sleep in patients undergoing knee replacement surgery using a regional anesthetic technique. METHODS: Ambulatory polysomnography (PSG) was performed on 3 nights the night before surgery (PSG1), the first night after surgery (PSG2), and the fifth postoperative night (PSG3). Postoperative analgesia was maintained with peripheral nerve catheters for the first 3 days and with oral opioids thereafter. In addition, nonsteroidal antiinflammatory drugs were administered. Postoperative pain was monitored using a visual analog scale. RESULTS: PSG was performed in 12 patients, 6 men and 6 women, with a mean age of 61 (±12) years. REM sleep was reduced from PSG1 (median 16.4%) to PSG2 (median 6.3%; P = 0.02). The Hodges-Lehmann estimate for the median reduction is -7.8% (95% confidence interval -14.8% to -0.7%). During PSG3, significantly more REM sleep was detected (median 15.4%) compared with PSG2 (P = 0.01). The Hodges-Lehmann estimate for this median increase is 10.0% (95% confidence interval 1.7%-25.3%). CONCLUSION: Postoperative reduction of REM sleep also occurs after surgery and regional anesthesia.