A Comparative Clinical Study between Clonidine and Tramadol with Bupivacaine in Caudal Epidural for Postoperative Analgesia in Pediatric Surgery

Analgesic efficacy of Clonidine as an adjuvant in ultrasound-guided rectus sheath block for midline incisional hernia repair - A randomized double-blind controlled trial

Background and Aims

Clonidine as an adjuvant has not been evaluated in rectus sheath block (RSB) for postoperative pain management in incisional hernia repair. The study aims to evaluate clonidine as an adjuvant in single-shot RSB along with general anesthesia (GA).

Material and Methods

This randomized, double-blind controlled study was conducted following IEC-Human approval and written informed consent from 30 patients of either sex, aged 16 to 60 years, ASA physical status I or II undergoing midline incisional hernia repair under GA. All patients received ultrasound-guided bilateral RSB following administration of GA. The subjects enrolled in the study were randomly allocated to receive either normal saline 1 mL (group B) or clonidine 1 μg/kg diluted to 1 mL with normal saline (group BC) as adjuvant along with 9 mL bupivacaine hydrochloride 0.25%. Inj. tramadol 1 mg/kg was administered for rescue analgesia. The primary outcome was the time to first request for analgesia, and secondary outcomes were total consumption of rescue analgesic over 24 h, numerical rating score (NRS), patients' satisfaction, hemodynamics, and side effects. Unpaired t-test and Chi-square test were used.

Results

On intergroup analysis, the mean time to first request for analgesia (in min) was significantly higher in group BC i.e., [9.60 (± 5.23) vs 5.33 (± 3.53); (P < 0.034]; whereas, the mean rescue analgesic consumption in 24 h (in mg) was higher in group B i.e., [(88.00 ± 60.97) vs (46.00 ± 48.08)]; (P < 0.045)]. Hemodynamic parameters i.e., mean blood pressure and heart rate were comparable between the two groups, and there were no side effects.

Conclusion

Clonidine as an adjuvant in single-shot ultasonography (USG)-guided RSB along with GA is efficacious for postoperative pain management following midline incisional hernia repair.

Analgesic Efficacy of Adjuvant Medications in the Pediatric Caudal Block for Infraumbilical Surgery: A Network Meta-Analysis of Randomized Controlled Trials

Various adjuvants are added to local anesthetics in caudal block to improve analgesia. The comparative analgesic effectiveness and relative rankings of these adjuvants are unknown. This network meta-analysis (NMA) sought to evaluate the comparative analgesic efficacy and relative ranking of caudal adjuvants added to local anesthetics (versus local anesthetics alone) in pediatric infra-umbilical surgery. We searched the United States National Library of Medicine database (MEDLINE), PubMed, and Excerpta Medica database (Embase) for randomized controlled trials (RCTs) comparing caudal adjuvants (clonidine, dexmedetomidine, ketamine, magnesium, morphine, fentanyl, tramadol, dexamethasone, and neostigmine) among themselves, or to no adjuvant (control). We performed a frequentist NMA and employed Cochrane's 'Risk of Bias' tool to evaluate study quality. We chose the duration of analgesia (defined as 'the time from caudal injection to the time of rescue analgesia') as our primary outcome. We also assessed the number of analgesic dose administrations and total dose of acetaminophen within 24 h. The duration of analgesia [87 randomized control trials (RCTs), 5285 patients] was most prolonged by neostigmine [mean difference: 513 min, (95% confidence interval, CI: 402, 625)]. Dexmedetomidine reduced the frequency of analgesic dose administrations within 24 h [29 RCTs, 1765 patients; -1.2 dose (95% CI: -1.6, -0.9)] and the total dose of acetaminophen within 24 h [18 RCTs, 1156 patients; -350 mg (95% CI: -467, -232)] the most.  Among caudal adjuvants, neostigmine (moderate certainty), tramadol (low certainty), and dexmedetomidine (low certainty) prolonged the duration of analgesia the most. Dexmedetomidine also reduced the analgesic frequency and consumption more than other caudal adjuvants (moderate certainty).

Clonidine as an Additive to Local Anesthetics in Caudal Block for Postoperative Analgesia in Pediatric Surgery: A Systematic Review and Meta-Analysis

Background: Clonidine is an anesthetic with favorable efficacy and safety profiles for caudal epidural block, but comparisons with other adjuvants need to be confirmed in pediatric patients. Aim: To investigate the effects of clonidine as an adjuvant in caudal epidural block to improve the intraoperative and postoperative analgesia in pediatric surgery. Methods: PubMed, Embase, and the Cochrane Library were searched for available papers published up to February 2021. The outcomes were pain score, duration of analgesia, complications, and number of analgesic requirements. The meta-analysis was performed using random-effects models. Results: Fifteen randomized controlled trials (RCTs) were included. There were no differences between clonidine and the control drug regarding the duration of analgesia (SMD = -0.71, 95%CI: -1.64, 0.23; I ² = 95.5%, P_{heterogeneity} < 0.001), pain score (SMD = 0.35, 95%CI: -0.28, 0.98; I ² = 80.8%, P_{heterogeneity} < 0.001), and requirement for additional analgesia (OR = 8.77, 95%CI: 0.70, 110.58, I ² = 81.9%, P_{heterogeneity} = 0.004), but using clonidine resulted in fewer complications than the control drugs (OR = 0.33, 95%CI: 0.20, 0.54, I ² = 21.8%, P_{heterogeneity} = 0.217). The sensitivity analysis showed that the results were robust. A publication bias was observed. Conclusion: Clonidine has the same efficacy as the other adjuvants for caudal epidural block for pediatric surgery but fewer complications. These results support clonidine as an adjuvant to local anesthetic, but additional studies should be conducted.