The Median Effective Dose of One Intravenous Bolus of Oxycodone for Postoperative Analgesia After Myomectomy and Hysterectomy With Local Ropivacaine Wound Infiltration: An Up–Down Dose-Finding Study

Abstract

BACKGROUND: Oxycodone has been shown to be an effective analgesic for early postoperative analgesia, especially for abdominal operations associated with severe visceral pain. However, the dose needed varies depending on the operation and application of multimodal analgesia, such as local ropivacaine wound infiltration. Therefore, we conducted this study to estimate the median effective dose (ED50) of oxycodone that provides analgesia for hysterectomy and myomectomy with local ropivacaine wound infiltration. METHODS: In this dose-finding study, the ED50 of oxycodone for postoperative analgesia was estimated separately for laparoscopic hysterectomy, transabdominal hysterectomy, laparoscopic myomectomy, and transabdominal myomectomy. We used the sequential allocation designed by Dixon. Trials were conducted simultaneously in the 4 surgical type groups. A predefined dose of oxycodone was injected 30 minutes before the end of the operation with an initial dose of 0.1 mg/kg. A series of trials were performed following the rule of a relative 10% increase in dose after inadequate analgesia and a relative 10% decrease in dose after adequate analgesia. The study was conducted until the collection of 7 crossover points was achieved. Local ropivacaine wound infiltration was administered during abdominal stitching. The mean blood pressure (MBP) and heart rate (HR) were analyzed to assess the hemodynamic changes associated with oxycodone administration. RESULTS: A total of 113 patients were included in the estimation of ED50: 28 each in the laparoscopic hysterectomy group and transabdominal myomectomy group, 27 in the transabdominal hysterectomy group, and 30 in the laparoscopic myomectomy group. The estimated oxycodone ED50 (95% confidence interval [CI]) after laparoscopic hysterectomy, transabdominal hysterectomy, laparoscopic myomectomy, and transabdominal myomectomy was 0.060 mg/kg (0.053–0.068), 0.079 mg/kg (0.072–0.086), 0.060 mg/kg (0.051–0.071), and 0.092 mg/kg (0.086–0.098), respectively, for postoperative analgesia with local ropivacaine wound infiltration. The ED50 of oxycodone was different between laparoscopic surgeries and transabdominal surgeries (P < .001). The MBP and HR before and after oxycodone injection were different, regardless of surgical type. CONCLUSIONS: The oxycodone ED50 for postoperative analgesia was lower for laparoscopic hysterectomy (0.060 mg/kg) and laparoscopic myomectomy (0.060 mg/kg) than for transabdominal hysterectomy (0.079 mg/kg) and transabdominal myomectomy (0.092 mg/kg) when combined with local ropivacaine wound infiltration. A single intravenous injection of oxycodone is associated with an acceptable decrease in MBP and HR within a short time.

WITHDRAWN: Efficacy of Dexmedetomidine as an Adjunct to Ropivacaine in Bilateral Dual-Transversus Abdominis Plane Blocks in Patients with Ovarian Cancer Underwent Cytoreductive Surgery

“…Oxycodone was given when the abdomen was closed and non-steroidal anti-inflammatory drug was used as rescue drugs. Oxycodone as a peripheral κ-opioid agonist provides effective visceral analgesia by activating receptors expressed on afferent nerves within the gut [22]. We observed a definite analgesic effect in TAP-DR group, due to the potential risks, the use and dosage of the drugs need to be quantified.…”

RETRACTED ARTICLE: Efficacy of dexmedetomidine as an adjunct to ropivacaine in bilateral dual-transversus abdominis plane blocks in patients with ovarian cancer who underwent cytoreductive surgery

“…Oxycodone was given when the abdomen was closed, and non-steroidal anti-inflammatory medication was used as a rescue drug. Oxycodone as a peripheral κ-opioid agonist provides effective visceral analgesia by activating receptors expressed on afferent nerves within the gut [ 27 ].…”

Sedation and Analgesia for Liver Cancer Percutaneous Radiofrequency Ablation: Fentanyl and Oxycodone Comparison

“…The perioperative NRS scores seemed to have statistically significant differences between two groups in this study, but the clinically significance remain controversial as NRS scores in both groups were low during the postoperative period even through the NRS scores in OXY group were lower than those in FEN group at all time points. Different from FEN, a µ-opioid receptor opioid, OXY acting on µ and κ receptors and has been shown as an effective analgesic for postoperative pain management after abdominal surgery with severe visceral pain [22,23]. One of possible mechanisms for treating visceral pain is the activation of sodium channels expressed on gut afferent nerves by peripheral κ receptor agonists [24,25].…”