Intraoperative Intravenous Infusion of Esmketamine Has Opioid-Sparing Effect and Improves the Quality of Recovery in Patients Undergoing Thoracic Surgery: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Postoperative thoracic surgery is often accompanied by severe pain, and opioids are a cornerstone of postoperative pain management, but their use may be limited by many adverse events. Several studies have shown that the perioperative application of esketamine adjuvant therapy can reduce postoperative opioid consumption. However, whether esketamine has an opioid-sparing effect after thoracic surgery is unclear. To explore the opioid-sparing effect of different doses of esketamine infusion during thoracic surgery and its impact on patient recovery. Randomized controlled study. A single-center study with a total of 120 patients. Patients were randomly allocated to 1 or 3 groups receiving intraoperative intravenous infusions of esketamine 0.15 mg · kg-1· h-1 (group K1), esketamine 0.25 mg · kg-1· h-1(group K2), or placebo (group C). Postoperative opioid consumption, and postoperative indicators like extubation time, PACU stay time, and adverse events were recorded for each group. The consumption of hydromorphone during the first 24 and 48 postoperative hours was significantly reduced in patients of group K2 compared to those of group C and group K1. The time to extubation and post anesthesia care unit (PACU) stay were significantly shorter in group K2 than in group K1 and group C. The time to first feed and off the bed time after surgery were shorter in groups K1 and K2 than in group C. Patients in group K2 were significantly satisfied with patient controlled intravenous analgesia (PCIA) than in groups K1 and C. The sample size calculation was based mainly on the index of hydromorphone consumption. Intraoperative intravenous esketamine at 0.25 mg · kg-1 · h-1 reduced postoperative opioids consumption by 34% in postoperative 24 hours and 30% in postoperative 48 hours in patients undergoing thoracic surgery. It also improved the quality of perioperative recovery.