BackgroundPostoperative sleep disturbance (POSD) caused by postoperative pain can impede the enhanced rapid recovery of elderly patients with colorectal cancer. We propose that perioperative intravenous lidocaine infusion may enhance postoperative sleep quality by alleviating postoperative pain in elderly patients undergoing laparoscopic radical resection for colorectal cancer. MethodsSixty-three elderly patients were divided into two groups: the lidocaine group (group L) and the placebo group (group C). Patients in group L received intravenous injection of lidocaine 1.5 mg/kg during the induction of anesthesia, followed by lidocaine 1.0 mg kg−1 h−1 during surgery and for 24 h after surgery. Patients in group C received the same volume of normal saline. The primary outcome was postoperative sleep function, which was evaluated using the Athens Insomnia Scale (AIS). The secondary outcomes included the pain-at-rest and pain-on-movement of patients at 2, 4, 6, 12, 24, 48, and 72 h after surgery, opioid and propofol consumption, bowel function recovery time, postoperative complications, and lidocaine side effects. ResultsCompared to group C, AIS scores in group L were significantly lower on day 1 (12.9 ± 4.0 vs 10.6 ± 3.9, P < 0.05), day 3 (8.6 ± 4.2 vs 6.2 ± 3.9, P < 0.05), and 1 week (4.3 ± 3.1 vs 2.2 ± 2.5, P < 0.05) after surgery. There were no significant differences in VAS scores between the two groups. The intraoperative consumption of propofol and remifentanil was significantly reduced in group L. Lidocaine infusion significantly shortened the recovery time of bowel function. There were no statistical differences between the two groups regarding the incidences of PONV and postoperative pulmonary complications. No cases of local anesthetic toxicity occurred in either group. ConclusionsPerioperative intravenous administration of lidocaine can facilitate the restoration of postoperative sleep function in elderly patients undergoing laparoscopic radical resection of colorectal cancer.