Discussion
obesity, postoperative pain, HTN, cancer, amputation, chronic diseases, pain, agitation, postoperative chronic pain, Alertness, acute postoperative morphine-resistant pain, PONV, metabolic syndrome, NRS, drug dependence
OBESITY, CHRONIC PAIN SYNDROMES, BLOOD, CANCER, CHRONIC DISEASES, HTN, SYMPATHOMIMETIC, METABOLIC SYNDROME, DISEASES
Herein, we compared the analgesic effect of ketamine and dexmedetomidine during bariatric surgery on postoperative total morphine consumption and found that ketamine significantly reduces the total morphine consumption postoperatively and dexmedetomine significantly reduces intraoperative total consumption of fentanyl.Around half a million treatments for obesity are performed each year globally. Most of these procedures are performed under laparoscopy [Our study showed lower intraoperative fentanyl doses, a shorter time to extubation, and improved MOASS and PONV scores which were all linked to dexmedetomidine infusion. Significantly lower NRS scores and postoperative morphine doses were linked to ketamine infusion. These findings showed that while ketamine reduced the need for morphine, dexmedetomidine effectively reduced the intraoperative fentanyl required and the time to extubation. Compared to dexmedetomidine, ketamine infusion minimizes the requirement for opioids for postoperative pain control with little side effects. Our findings were similar to those of Garg et al., who demonstrated that ketamine and dexmedetomidine provide good and safe analgesia, decrease the need for morphine, and increase the pain-free period during the postoperative period in patients undergoing spinal surgery [In our cohort, demographic data were similar among the three groups. The most common diseases were DM and HTN, which are correlated with obesity as components of metabolic syndrome [Intraoperative MAP tended to be higher in the ketamine group than in the other groups. Conversely, HR values were similar between the ketamine group and control group, suggesting that the sympathomimetic action of ketamine does not preclude an analgesic effect. HR values were significantly lower in the dexmedetomidine group, probably because of decreased sympathetic outflow, and this finding supports the analgesic effect of this drug. Blood pressure and HR did not decrease significantly across the groups, suggesting that both drugs can maintain stable hemodynamics during surgery.In our cohort, the need for analgesics intraoperatively was significantly lower in the dexmedetomidine group than in the other groups. Further, ketamine group was associated with a lower fentanyl requirement than control group. Consistent with our finding, Bakhamees et al. found that dexmedetomidine decreased the need for fentanyl intraoperatively in patients with MO undergoing laparoscopic bypass surgery [Dexmedetomidine marginally decreased the time to extubation and marginally improved MOASS scores. Alertness returned to normal within 60 min postoperatively in all groups. There were no cases of emergencies or agitation during recovery from anesthesia. Consistent with our results, Zeeni et al. observed that dexmedetomidine and morphine infusions administered during laparoscopic bariatric surgery led to the same level of postoperative sedation [NRS scores correlated with the need for morphine as rescue analgesia in the postoperative period. NRS scores were significantly lower in the ketamine group at most time points. Our primary outcome was the effect of ketamine and dexmedetomidine on total morphine requirement 24 h post-surgery. The need for morphine was lowest in the ketamine group (mean: 3 ± 3 mg). Further, the need for morphine was marginally lower in the dexmedetomidine group than in control group; however, the benefits of reduced postoperative morphine requirement cannot be ignored. Similar to our results, Mehta et al. found that ketamine infusion decreased postoperative analgesic requirements compared with a control in patients undergoing laparoscopic bariatric surgery [In terms of postoperative pain control, ketamine can also help reduce the development of chronic post-operative pain, in addition to its opioid-relieving effect. This can be achieved through the inhibition of the receptors of the N-methyl-D-aspartate and by reduction of wind-up and central sensitization [Our results demonstrated that dexmedetomidine infusion reduced PONV scores, suggesting that this drug had an anti-emetic effect during the postoperative course. Hussein and Mostafa showed that dexmedetomidine reduced PONV in patients undergoing bariatric surgery compared with controls [For these reasons, we suggest that ketamine or dexmedetomidine should be considered as part of multidisciplinary therapy for all patients with chronic diseases or with chronic pain syndromes undergoing painful surgeries. Future long-term studies are essential to address the issue of prevention of postoperative chronic pain syndromes. Additionally, we suggest that the effects of ketamine and dexmedetomidine in patients that are at high risk for developing acute postoperative morphine-resistant pain (cancer patients, chronic pain syndromes, amputation, and drug dependence) should be investigated. Combined effect of both drugs is a point of future study.