Effectiveness of different doses of dexmedetomidine on intraoperative haemodynamic profiles and postoperative pain in patients undergoing abdominal surgery at Dilla University Referral Hospital, Ethiopia, 2024: a double-blind randomized controlled trial

Abstract

Background and objective: Abdominal surgery stands as one of the most frequently conducted procedures across surgical specialties, accounting for up to half of surgery-related expenses. Hemodynamic instability emerges as a significant concern during anaesthesia and surgery, provoked by the stress of intubation, surgical incision, and anaesthetic agents. Following abdominal surgery, pain is an inevitable consequence, typically managed with opioid-based analgesia. However, the adverse effects associated with opioids often overshadow their analgesic benefits, particularly in the context of abdominal surgery. Consequently, there exists a necessity to explore and assess alternative non-opioid pain management options post-abdominal surgery as part of a broader strategy to reduce opioid usage. The primary aim of this investigation is to assess the effectiveness of varying doses of dexmedetomidine in regulating intraoperative hemodynamics and alleviating postoperative pain in patients undergoing abdominal surgery.

Methods: Ethical clearance and institutional review board were obtained from the ethical clearance committee of Dilla University College of Medicine and Health Sciences with protocol unique number of duirb/008/22-01. Our trial has been prospectively registered on the Pan African Clinical Trial Registry with a unique identification number for the registry PACTR202208813896934. Statistical package and analysis were performed by using SPSS version 25. The distribution of data was checked by using Shapiro-Wilk test and the homogeneity of variance was checked by Levene's test. Analysis of variance (ANOVA) and Kruskal-Wallis H test were used for normally distributed continuous data and non-normally distributed or non-parametric data, respectively. P value less than 0.05 with a power of 90% was considered statistically significant.

Result: There was a statistically significant increase in mean SBP in the control group at the different critical time points (P<0.05), as compared to the baseline value, while there was no significant difference in mean systolic blood pressure (SBP) between the baseline and all other levels for group 2 and group 3. A statistically significant increase in mean arterial pressure (MAP) was detected in the control group at immediately after intubation (P=0.009) as compared to the baseline value, while a statistically significant reduction in mean heart rate (HR) was observed in group 3 at 15th min after infusion and at 30th 30 min after induction compared to baseline with a P value of 0.002 and 0.008, respectively.Conclusion:Perioperative low-dose infusion of dexmedetomidine at the rate of 0.4 mcg/kg/h is a useful anaesthesia adjuvant to control hemodynamic stress response to critical periods. It is wise to use this infusion dose as part of general anaesthesia to achieve better hemodynamic stability.

Keywords: Anaesthesia; Ethiopia; dexmedetomidine; haemodynamic; perioperative; surgery.

Figure 1

Flow diagram of the study.

Figure 2

Trends of mean arterial pressure (MAP). Hint:1- baseline, 2- at 15th min after infusion, 3- at immediately after intubation, 4- at 5th min after induction, 5- at 10th min after induction, 6- at 15th min after induction, 7- at 30th min after induction, 8- at immediately after extubation, 9- at 5th min after extubation, 10 at 10th min after extubation.

Figure 3

Trends of mean heart rate (HR). Hint:1- baseline, 2- at 15th min after infusion, 3- at immediately after intubation, 4- at 5th min after induction, 5- at 10th min after induction, 6- at 15th min after induction, 7- at 30th min after induction, 8- at immediately after extubation, 9- at 5th min after extubation, 10 at 10th min after extubation.