Perioperative use of ketamine infusion versus dexmedetomidine infusion for analgesia in obese patients undergoing bariatric surgery: a double-blinded three-armed randomized controlled trial

Abstract

Background Bariatric surgery depends on the development of novel anesthetic techniques to reduce the incidence of complications and improve postoperative outcomes. Ketamine and dexmedetomidine have been used for perioperative analgesia and we hypothesized that they would decrease postoperative morphine requirements. The objective of this trial is to study whether choice of ketamine or dexmedetomidine infusion would affect postoperative total morphine consumption. Methods Ninety patients were equally randomized into three groups. The ketamine group received a bolus dose (0.3 mg/kg) of ketamine over 10 min, followed by an infusion of the same drug (0.3 mg/kg/h). The dexmedetomidine group received a bolus dose (0.5 mcg/kg) of dexmedetomidine over 10 min, followed by an infusion of this drug (0.5 mg/kg/h). The control group received a saline infusion. All infusions were given till 10 min before the end of surgeries. Intraoperative fentanyl was given when patient developed hypertension and tachycardia despite adequate anesthesia and muscle relaxation. Postoperative pain was managed by a rescue dose of 4 mg of IV morphine, with a minimum interval of 6 h between morphine doses if the numerical rating scale (NRS) score was ≥ 4. The primary outcome was the total morphine dose, and the secondary outcomes were intraoperative fentanyl requirement, time to extubation, postoperative nausea and vomiting (PONV), NRS scores, and modified observer’s agitation/sedation scale (MOASS) scores. Results Compared with ketamine, dexmedetomidine decreased the need for fentanyl intraoperatively (160 ± 42 µg), shortened the time to extubation (3 ± 1 min), and improved MOASS and PONV scores. In turn, ketamine decreased postoperative NRS scores and the need for morphine (3 ± 3 mg). Conclusions Dexmedetomidine treatment was associated with lower fentanyl doses, a shorter time to extubation, and better MOASS and PONV scores. Ketamine treatment was associated with significantly lower NRS scores and morphine doses. These results indicated that dexmedetomidine effectively decreased intraoperative fentanyl requirement and the time to extubation, while ketamine decreased the need for morphine. Trial registration This trail was registered on the clinicaltrials.gov registry (NCT04576975) on October 6, 2020.

Non-Opioid Analgesics and Adjuvants after Surgery in Adults with Obesity: Systematic Review with Network Meta-Analysis of Randomized Controlled Trials

“…The characteristics of the included RCTs are available for consultation in SMC2. An analysis shows that out of the total participants, 1795 patients were allocated to the control (1491 placebo or no intervention and 304 to a comparator), while 1775 were allocated to treatment (135 to Ibuprofen [28,33], 207 to acetaminophen (or paracetamol) [25,27,29,33], 329 to ketamine [16,20,37,39,40,42,43,45,49,50,52], 23 to ketamine plus clonidine [18], 68 to ketamine plus magnesium [39,42], 391 to dexmedetomidine [15,17,22,26,31,36,47,49], 341 to lidocaine [21,26,38,41,44,46,47,51], 70 to magnesium [34,48], 112 to gabapentin [23,32,35], 69 to pregabalin [19,30], and 30 to pregabalin plus dexmedetomidine [24]). Regarding the comparison between treatment and the comparator, acetaminophen was compared with ibuprofen in 89 patients …”

“…The detailed reasons for the risk of biased judgments are available in SMC4. [25,27,29,33], 329 to ketamine [16,20,37,39,40,42,43,45,49,50,52], 23 to ketamine plus clonidine [18], 68 to ketamine plus magnesium [39,42], 391 to dexmedetomidine [15,17,22,26,31,36,47,49], 341 to lidocaine [21,26,38,41,44,46,47,51], 70 to magnesium [34,48], 112 to gabapentin [23,32,35], 69 to pregabalin [19,30], and 30 to pregabalin plus dexmedetomidine [24]). Regarding the comparison between treatment and the comparator, acetaminophen was compared with ibuprofen in 89 patients [28,33], clonidine with dexmedetomidine in 30 patients [22], ketamine with dexmedetomidine in 54 patients [47,…”

“…Postoperative pain was evaluated at different time points postoperatively, at the end of anesthesia [17,18,22,23,27,30,33,35,38,42,47,49], 30 min [17,18,31,40,[48][49][50], 60 min [15,17,18,20,23,30,31,38,40,47,[49][50][51], 2 h [15,20,23,31,33,38,40,[48][49][50][51], 4 h [23,32,33,35,36,38,42,48,51], 6 h…”

The nuts and bolts of multimodal anaesthesia in the 21st century: a primer for clinicians

“…In MMA, ketamine is primarily used for its analgesic properties and ability to reduce the need for opioids [ 86 ▪ , 87 ]. However, it also has an antidepressant effect that can be beneficial during surgery [ 88 ▪ ].…”

General Anesthetic Care of Obese Patients Undergoing Surgery: A Review of Current Anesthetic Considerations and Recent Advances

“…Therefore, current research on ketamine use in obese patients is focused on determining if ketamine reduces the risk of respiratory complications in obese patients and provides adequate pain control during and after surgery. Several clinical trials are showing promising results when ketamine replaces opioids by reducing the risk of respiratory distress in obese patients while still maintaining adequate pain relief [ 99 , 100 ].…”