Ultrasound-Guided Quadratus Lumborum Block Using Bupivacaine and Verapamil versus Bupivacaine as Postoperative Analgesia in Abdominal Surgeries

Abstract Background Postoperative pain control is significant challenge in medical practice, and insufficient postoperative pain control can increase the incidence of many postoperative complications. Regional anesthesia can efficiently alleviate postoperative pain, avoid opioid- related side effects and decrease the risk of developing postoperative chronic pain. Ultrasound-guided quadratus lumborum block (QLB) is a posterior abdominal wall block. It was proved to reduce postoperative opioid consumption. In recent years, the practice of adding adjuvants to local anesthetics in nerve blocks emerged to decrease dose of anesthetics and prolong time of analgesia. Among such adjuvants is verapamil which showed efficacy in prolongation of the action of local anesthetics in several studies when used in supraclavicular brachial plexus block. Objective To evaluate the analgesic effect of quadratus lumborum block (QLB) with and without the addition of verapamil in the postoperative period after abdominal surgeries. Methods Twenty patients scheduled for abdominal surgeries under general anesthesia were recruited in this prospective randomized comparative clinical study from Ain Shams University hospitals, Cairo, Egypt within a period of 6 months and were divided into two groups. Results This study showed that there was no statistically significant difference between both groups according to demographic data, age, sex, ASA and BMI, with p-value (P = 0.611; P = 0.371; P = 1.000 and P = 0.869) respectively. There was statistically significant higher mean value of heart rate “beat/min” after 2 hrs. and after 4 hrs. in control group was 82.20±9.58 and 87.50±10.61 comparing to verapamil group was 70.40±9.83 and 75.00±11.42, respectively, with p-value (p = 0.014 and p = 0.021). While, the rest have insignificant difference, with p- value (p > 0.05). Statistically significant higher mean value of MAP (mmHg) in control group was 86.90±6.44 and 87.00±6.78 comparing to verapamil group was 76.60±6.48 and 80.90±5.76, respectively, with p-value (p = 0.002 and p = 0.044). While, there rest have insignificant difference, with p-value (p > 0.05). An increase in median of VAS score in the two groups over the periods from the after 1hr, but the most increase in the control group comparing to verapamil group; as there was a statistically significant difference between groups according to VAS score at after 6 hr., after 12 hrs. and After 18 hrs., with p-value (p < 0.05). Need of analgesia was statistically significantly faster in control group was 5.80±2.39 compared to verapamil Group was 13.20±6.20, according to time of 1st rescue analgesia “hrs.”, with p-value (p = 0.002). Statistically significant higher mean value of total morphine (mg) in control group was 18.50±4.12 compared to verapamil group was 11.50±3.37, with p-value (p < 0.001). Conclusion The study showed that the addition of verapamil to bupivacaine in QLB improved the qualities of the block which was proved by longer time before rescue analgesia, lower VAS scores and lower morphine (mg) consumption in verapamil group compared to control group.