Dexmedetomidine versus clonidine adjuvants to levobupivacaine for ultrasound-guided transversus abdominis plane block in paediatric laparoscopic orchiopexy: Randomized, double-blind study

Ropivacaine combined with dexmedetomidine in ultrasound-guided axillary brachial plexus block in children, a randomized controlled trial

OBJECTIVE

In this study, we evaluated the efficacy and safety of 1 μg/kg dexmedetomidine as an adjuvant treatment to ropivacaine in children undergoing upper limb surgeries under ultrasound-guided axillary brachial plexus blocks and general anesthesia.

METHODS

We enrolled 90 children (aged 1-8 years; ASA I-II) undergoing closed reduction and internal fixation for upper extremity fractures at the Xiamen Children's Hospital and randomly assigned them to one of two groups: L (injection with 0.25% ropivacaine) or D (injection with 0.25% ropivacaine containing 1 μg/kg dexmedetomidine) using the random number table method. The main outcome indicators recorded were the facial expression, leg activity, position, crying, and Face, Legs, Activity, Cry, and Consolability (FLACC) scale scores of children after surgery and the duration of block and analgesia maintenance. The secondary outcome indicators were vital sign data at the time of ultrasound probe placement (T1), at the time of block completion (T2), prior to the beginning of surgery (T3), 5 min after the beginning of surgery (T4), and at the end of surgery (T5), as well as the time of postoperative recovery, the number of cases of remedial analgesia, and complications.

RESULTS

There was no statistical difference between the two groups in terms of general data, block completion time, postoperative recovery time, and complications (P > 0.05). Compared to the L group, the D group had significantly lower FLACC scores at 6 h after surgery, as well as significantly lower systolic blood pressure, diastolic blood pressure, and heart rate values at T4 and T5, and significantly longer duration of postoperative analgesia maintenance (all P < 0.05).

CONCLUSION

Dexmedetomidine (1 μg/kg) as a local anesthetic adjuvant to ropivacaine can alleviate pain at 6 h postoperatively, prolong analgesia maintenance, and reduce intraoperative blood pressure and heart rate in pediatric patients undergoing closed reduction and internal fixation for upper extremity fractures, with no obvious complications or delayed recovery.

CLINICAL REGISTRY NUMBER

Registration website: www.chictr.org.cn, Registration number: ChiCTR2200065163, Registration date: October, 30, 2022.

Efficacy of adjuvant dexmedetomidine on penile block for pediatric hypospadias repair

INTRODUCTION

The management of postoperative pain, particularly in younger children, presents a challenge due to their limited ability to articulate the intensity of pain, lower pain threshold, and restricted availability of approved analgesics for pediatric use. Peripheral nerve blocks may be favored over neuraxial blocks because they allow quicker mobilization after surgery.

OBJECTIVE

The present study aims to investigate the potential impact of adding dexmedetomidine to a local anesthetic (bupivacaine) on the analgesic efficacy in dorsal penile nerve block in hypospadias repair surgery.

METHOD

In this prospective double-blinded clinical trial, 50 children aged between 6 months and 6 years old undergoing hypospadias repair surgery participated. Analgesia was administered through a dorsal penile nerve block (DPNB) at the end of surgery. Participants were divided into two groups; one received bupivacaine alone, and the other received dexmedetomidine and bupivacaine in DPNB. Pain and sedation levels were assessed with FLACC score and MOAA/S score, respectively, at 0,1,2 and 4 h after surgery. Vital signs and adverse effects were also recorded, including hemodynamic changes, nausea, and vomiting.

RESULT

There was no statistically significant difference in demographic variables. As illustrated in Figure, the median of FLACC score in group BD was significantly lower compared to group B at every measured time point. MOAA/S score was significantly lower in group BD than in group B (p < 0.001), indicating a higher sedation level. None of the participants in either group experienced any adverse effect except for vomiting, which was not statistically significant (8 % in group B vs. 4 % in group BD, p > 0.999).

DISCUSSION

Several studies have documented the supplementary analgesic properties of dexmedetomidine when used in conjunction with local anesthetic during various surgical procedures and nerve blocks. The present study provides evidence for the additional analgesic efficacy of dexmedetomidine and bupivacaine in the context of dorsal penile nerve block during hypospadias repair surgery while not yielding any significant adverse outcomes. Although the patients in our study were monitored for 4 h in the postanesthesia care unit (PACU), conducting a more comprehensive assessment of patients is advisable.

CONCLUSION

The findings of our study indicate that incorporating dexmedetomidine alongside bupivacaine in dorsal penile nerve block during hypospadias repair surgery may lead to enhanced management of postoperative pain. The lack of adverse effects implies it may be a potentially safe supplementary pain reliever for surgical procedures.

Effect of ultrasound-guided femoral nerve block with dexmedetomidine and ropivacaine on postoperative analgesia in patients undergoing total knee arthroplasty: a randomized controlled trial

Background

Dexmedetomidine, a potent and highly selective α2-adrenoreceptor agonist, has become a popular adjuvant to local anesthetics. This study was designed to investigate the effect of dexmedetomidine with ropivacaine for femoral nerve block on postoperative analgesia after total knee arthroplasty.

Methods

Forty-six patients after total knee arthroplasty received ultrasound-guided femoral nerve block with either 0.3% ropivacaine alone (group R) or 0.3% ropivacaine with 0.5 μg/kg dexmedetomidine (group RD). Total 24-h sufentanil consumption, visual analogue scale (VAS) pain scores, frequency of patient-controlled analgesia (PCA) pressed, Ramsay sedation score, the incidence of bradycardia and hypotension, and incidence of postoperative nausea and vomiting (PONV) were recorded.

Results

Compared to group R, the total 24-h sufentanil consumption was significantly reduced (110.76 ± 11.56 vs. 99.09 ± 13.31; P<0.05), the VAS scores were lower at 10 and 12 h postoperatively [3(2-3) vs. 2(1-2) and 3(2-3) vs. 2(1-3), respectively; P<0.05], the frequency of PCA pressed was lower at 8-12 and 12-16-h time intervals [(5(3-6) vs. 2(1-3) and 4(3-4) vs. 2(1-3), respectively; P<0.05]. However, there were no differences in Ramsay's sedation score and the incidence of PONV. Also, no patient experienced bradycardia and hypotension.

Conclusions

0.5 μg/kg dexmedetomidine with 0.3% ropivacaine for femoral nerve block significantly decreased the total 24-h sufentanil consumption, prolonged and enhanced the analgesic efficacy of ropivacaine, without clinically relevant cardiovascular depression or over-sedation in patients undergoing total knee arthroplasty.

Dexmedetomidine as an Adjuvant in Peripheral Nerve Block

Peripheral nerve block technology is important to balanced anesthesia technology. It can effectively reduce opioid usage. It is the key to enhance clinical rehabilitation as an important part of the multimodal analgesia scheme. The emergence of ultrasound technology has accelerated peripheral nerve block technology development. It can directly observe the nerve shape, surrounding tissue, and diffusion path of drugs. It can also reduce the dosage of local anesthetics by improving positioning accuracy while enhancing the block's efficacy. Dexmedetomidine is a highly selective drug α₂-adrenergic receptor agonist. Dexmedetomidine has the characteristics of sedation, analgesia, anti-anxiety, inhibition of sympathetic activity, mild respiratory inhibition, and stable hemodynamics. Numerous studies have revealed that dexmedetomidine in peripheral nerve blocks can shorten the onset time of anesthesia and prolong the time of sensory and motor nerve blocks. Although dexmedetomidine was approved by the European Drug Administration for sedation and analgesia in 2017, it has not yet been approved by the US Food and Drug Administration (FDA). It is used as a non-label drug as an adjuvant. Therefore, the risk-benefit ratio must be evaluated when using these drugs as adjuvants. This review explains the pharmacology and mechanism of dexmedetomidine, the effect of dexmedetomidine on various peripheral nerve block as an adjuvant, and compare it with other types of adjuvants. We summarized and reviewed the application progress of dexmedetomidine as an adjuvant in nerve block and look forward to its future research direction.

Ultrasound-guided quadratus lumborum block provided more effective analgesia for children undergoing lower abdominal laparoscopic surgery: a randomized clinical trial

BACKGROUND

Postoperative pain treatment for pediatrics is often inadequate and the evidence of pediatric postoperative analgesia is scarce. To our knowledge, no report regarding the comparison among caudal block, transversus abdominis plane (TAP) block and quadratus lumborum (QL) block for children undergoing lower abdominal laparoscopic surgery was found at present. Thus this trial aimed to compare the efficacies of them for children undergoing lower abdominal laparoscopic surgery.

METHODS

One hundred and eighty children aged from 1 to 12 years undergoing lower abdominal laparoscopic surgery were included and randomized to receive caudal block, TAP block or QL block. The primary outcome was the Face, Legs, Activity, Cry, and Consolability (FLACC) score at 30 min, 1 h, 4 h, 8 h, 12 h, and 24 h and tramadol consumption during first 24 h postoperatively. Secondary outcomes included the number of children received tramadol, time to first tramadol request, parents' satisfaction and postoperative adverse reactions.

RESULTS

The QLB group had lower postoperative FLACC scores at 8 h (median difference - 0.43, P = 0.03) than the Caudal group and at 4 h (median difference - 0.6, P = 0.001) and 8 h (median difference - 0.43, P = 0.03) than the TAPB group. The tramadol consumption was lower in the QLB group (28.43 ± 6.55) than the TAPB group (37.17 ± 6.12, P = 0.023). Although the number of children received tramadol did not differ among the three groups, the time to first tramadol request was longer in the QLB group (7.20 ± 0.79) than the caudal group (8.42 ± 0.61, P = 0.008). No statistical difference was observed concerning other secondary outcomes.

CONCLUSIONS

QLB produced more effective postoperative analgesia for children undergoing laparoscopic abdominal surgery compared with the TAPB and caudal block.

Injectable electrospun fiber-hydrogel composite sequentially releasing clonidine and ropivacaine for prolonged and walking regional analgesia

Rationale: Peripheral nerve block is a traditional perioperative analgesic method for its precise pain control and low systemic toxicity. However, a single low dose of local anesthetic merely provides a few hours of analgesia, and high dose results in irreversible toxicity, whereas continuous infusion of anesthetics is expensive and complicated. Therefore, it is necessary to develop a long-acting and sensory-selective local anesthetic for safe perioperative analgesia. Methods: An injectable composite comprising ropivacaine-loaded poly (ε-caprolactone) electrospun fiber and clonidine-loaded F127 hydrogel (Fiber-Rop/Gel-Clo composite) was developed for long-acting and walking regional analgesia with barely one dose. The peripheral nerve blockade effect of the composite was evaluated in a rat sciatic nerve block model. Also, the biodegradability and biosafety of the composite was evaluated. Results: The preferentially released Clo from the hydrogel rapidly constricted the peripheral arterial vessels, reducing the blood absorption of Rop and thus enhancing the local Rop accumulation at the injection site. The subsequently sustainable release of Rop from the fiber, significantly prolonged the sciatic nerve block of rats. Remarkably, an amazing sensorimotor segregation effect was achieved, as the sensory blockade (32.0 ± 1.4 h) lasted significantly longer than the motor blockade (20.3 ± 0.9 h). Additionally, the Fiber-Rop/Gel-Clo composite presented good biodegradability and biosafety in vivo. Conclusions: Our designed Fiber-Rop/Gel-Clo composite with minimal invasion, prolonged synergistic analgesia, and strikingly sensorimotor segregation effect, posted a promising prospect for regional long-term walking analgesia in clinical treatment.

Dexmedetomidine as an adjunct to peripheral nerve blocks in pediatric patients

BACKGROUND

Combining local anesthetics with dexmedetomidine (DEX) for nerve blocks has been tested and confirmed as an alternative technique to strengthen analgesia in adults, but the evidence supported this proposal in pediatrics was not convincing enough. Thus, we intend to conduct a meta-analysis to make an appraisal of the effects of DEX as a local anesthetic adjuvant on peripheral nerve blocks in children.

METHODS

The analysis has been registered on https://www.crd.york.ac.uk/prospero/ with the registration number CRD42021254029 on June 10th, 2021. PubMed, Ovid MEDLINE, Embase and Cochrane central register were searched for the randomized controlled trials (RCTs) that are relevant to child/pain/DEX or block up to April 30, 2021.

RESULTS

Eight RCTs were included for data analysis. The pooled results showed a significantly reduced number of patients who required postoperative analgesics within DEX groups [odds ratio = 0.1, 95% confidence interval (CI) 0.03-0.32, P < 0.001]. And DEX significantly prolonged the duration of analgesia of local anesthetics in the meantime [standardized mean difference (SMD) = 4.93, 95% CI 3.02-6.83, P < 0.001]. Nevertheless, adding DEX as an adjunct to local anesthetics would significantly decrease heart rate (SMD = - 0.95, 95% CI - 1.45 to - 0.45, P < 0.001) and increase sedation score (SMD = 1.6, 95% CI 0.53-2.66, P = 0.003) simultaneously.

CONCLUSIONS

Adding DEX as an adjunct to peripheral nerve blocks can prolong analgesia until postoperative 8 hours in pediatric patients. However, the benefits should be weighed against the increasing risk of bradycardia and sedation in critical children.

A Comparative Study on the Effects of Ketofol, Dexmedetomidine, and Isofol in Anesthesia of Candidates for Dilatation and Curettage

Background

Dilatation and curettage (D & C) is one of the relatively common surgeries among women. Familiarity with the analgesics, along with their different uses and specific characteristics, can help to determine the best and most appropriate drug to control pain in the patients.

Objectives

This study aimed to compare the effects of ketofol, dexmedetomidine, and isofol in anesthesia of candidates for D & C.

Methods

In this double-blind clinical trial, 150 candidates for D & C surgeries with ASA class 1 and 2 were included. Patients were randomly divided into three groups. The first group received ketamine + propofol, the second group received dexmedetomidine, and the third group received isofol (isoflurane + propofol). Any hemodynamic changes or respiratory disorders, including apnea or hypoventilation, drop in the level of blood oxygen saturation, and the need for respiratory support, were recorded and compared.

Results

Hypoventilation was observed in 47 patients in isofol group, 18 in the dexmedetomidine group, and 42 in ketofol group. Also, 48 patients in the isofol group, eight in the dexmedetomidine group, and 33 in the ketofol group experienced apnea. Moreover, 17 patients in the dexmedetomidine group, 35 in the ketofol group, and eight in the isofol group experienced bradycardia. The rate of bradycardia was significantly higher in the dexmedetomidine group (70%) compared to the other two groups, and the rate of hypotension was significantly higher in the isofol group (P = 0.001).

Conclusions

According to the results, dexmedetomidine was associated with fewer complications during general anesthesia in D & C surgery.