Mayank Gupta, Priyanka Gupta1, Dhananjay Kumar Singh1. 1. Department of Anaesthesia, ICU and Pain Shri Guru Ram Rai Institute of Medical and Health Sciences, Shri Mahant Indiresh Hospital Patel Nagar, Dehradun, Uttarakhand-248001.
Abstract
BACKGROUND: The extended analgesic efficacy of intrathecal dexmedetomidine (ITD) has been investigated in a few clinical trials; however, there is a lack of conclusive evidence upon its ideal dosage. OBJECTIVES: To elucidate the dose-response relationship between ITD and subarachnoid block characteristics, particularly the duration of analgesia and differential analgesia (DA: defined as time difference from the offset of motor blockade to the first analgesic requirement on numerical rating scale = 4.0). STUDY DESIGN: Prospective, randomized double blind active control trial. SETTING:Medical college teaching hospital. METHODS:Ninety adult (18 - 60 years) patients undergoing elective lower abdominal and lower limb surgeries were randomized into 3 groups to receive intrathecal 0.5% bupivacaine 3 mL with 2.5 µg (group BD2.5), 5µg (group BD5), or 10 µg (group BD10) dexmedetomidine in 0.5 mL normal saline. The 2 segment sensory regression times (TSSRT), duration of motor blockade analgesia, DA, and perioperative adverse effects were assessed. The primary outcome was duration of analgesia and DA. STATISTICS: ANOVA, Kruskal Wallis test, Chi-square (x2), and Fisher's exact test, significance: P < 0.05. RESULTS: The onset of sensory block was significantly earlier in group BD10 compared with group BD5 (P = 0.035) and BD2.5 (P = 0.010) while the onset of motor block was significantly earlier in group BD10 compared with BD2.5 (P = 0.020). There was a significant and dose-dependent prolongation of the duration of sensory block (127.50, 149.17, and 187.50 minutes; P < 0.001), motor block (258.50, 331, and 365 minutes; P < 0.001), analgesia (306.17, 396.50, and 512 minutes; P < 0.001), and DA (47.67, 65.50, and147 minutes; P < 0.001) with escalating doses of ITD, respectively. Group BD10 required significantly fewer rescue analgesics compared with other 2 groups (P = 0.001). Except for mild sedation which was significantly higher in group BD10; all the groups were comparable with respect to hemodynamic and other adverse effects. LIMITATIONS: Lack of placebo group, exclusion of higher doses (15µg) of ITD, and short duration of postoperative follow-up. CONCLUSIONS: The addition of 10 µg compared with 2.5 µg or 5µg ITD to 0.5% hyperbaric bupivacaine is associated with significantly earlier onset of sensory and motor block as well as prolonged duration of sensory block, motor block, analgesia, and DA with a comparable adverse effect profile.
RCT Entities:
BACKGROUND: The extended analgesic efficacy of intrathecal dexmedetomidine (ITD) has been investigated in a few clinical trials; however, there is a lack of conclusive evidence upon its ideal dosage. OBJECTIVES: To elucidate the dose-response relationship between ITD and subarachnoid block characteristics, particularly the duration of analgesia and differential analgesia (DA: defined as time difference from the offset of motor blockade to the first analgesic requirement on numerical rating scale = 4.0). STUDY DESIGN: Prospective, randomized double blind active control trial. SETTING: Medical college teaching hospital. METHODS: Ninety adult (18 - 60 years) patients undergoing elective lower abdominal and lower limb surgeries were randomized into 3 groups to receive intrathecal 0.5% bupivacaine 3 mL with 2.5 µg (group BD2.5), 5µg (group BD5), or 10 µg (group BD10) dexmedetomidine in 0.5 mL normal saline. The 2 segment sensory regression times (TSSRT), duration of motor blockade analgesia, DA, and perioperative adverse effects were assessed. The primary outcome was duration of analgesia and DA. STATISTICS: ANOVA, Kruskal Wallis test, Chi-square (x2), and Fisher's exact test, significance: P < 0.05. RESULTS: The onset of sensory block was significantly earlier in group BD10 compared with group BD5 (P = 0.035) and BD2.5 (P = 0.010) while the onset of motor block was significantly earlier in group BD10 compared with BD2.5 (P = 0.020). There was a significant and dose-dependent prolongation of the duration of sensory block (127.50, 149.17, and 187.50 minutes; P < 0.001), motor block (258.50, 331, and 365 minutes; P < 0.001), analgesia (306.17, 396.50, and 512 minutes; P < 0.001), and DA (47.67, 65.50, and147 minutes; P < 0.001) with escalating doses of ITD, respectively. Group BD10 required significantly fewer rescue analgesics compared with other 2 groups (P = 0.001). Except for mild sedation which was significantly higher in group BD10; all the groups were comparable with respect to hemodynamic and other adverse effects. LIMITATIONS: Lack of placebo group, exclusion of higher doses (15µg) of ITD, and short duration of postoperative follow-up. CONCLUSIONS: The addition of 10 µg compared with 2.5 µg or 5µg ITD to 0.5% hyperbaric bupivacaine is associated with significantly earlier onset of sensory and motor block as well as prolonged duration of sensory block, motor block, analgesia, and DA with a comparable adverse effect profile.
Authors: Mohammad K Al Nobani; Mohammed A Ayasa; Tarek A Tageldin; Abduljabbar Alhammoud; Marcus Daniel Lance Journal: Local Reg Anesth Date: 2020-12-15