A comparative study of dexmedetomidine and fentanyl as adjuvants to levobupivacaine for caudal analgesia in children undergoing lower limb orthopedic surgery

Reconsidering injection volume for caudal epidural block in young pediatric patients: a dynamic flow tracking experimental study

INTRODUCTION

Caudal epidural block is a commonly used analgesic technique in pediatric patients. Ultrasound could be used to increase the accuracy of the block by visual confirmation of the drug-spreading. Therefore, we aimed to estimate the cephalad spread of injection volume by caudal route using dynamic ultrasound imaging in young pediatric patients.

METHODS

Forty patients, aged 6-24 months, undergoing foot surgery were included. After inducing general anesthesia, an angiocatheter was inserted into the sacral canal under ultrasound guidance. Thereafter, the probe was placed in the paramedian sagittal oblique position, and prepared 0.15% ropivacaine was injected, 1 mL at a time, up to 1.0 mL.kg-1. The ultrasound probe was moved cranially following the bulk flow of local anesthetics. Our primary outcome was the required volume of local anesthetics to reach each level of interlaminar space.

RESULTS

The dynamic flow tracking was available in 39 patients, and the required volume of the injectate to reach L5-S1, L4-L5, L3-L4, L2-L3, L1-L2, T12-L1, and T11-T12 was 0.125, 0.223, 0.381, 0.591, 0.797, 0.960, and 1.050 mL.kg-1, respectively. The required volume to reach the immediate upper spinal level was inconsistent across various spinal levels.

CONCLUSIONS

Local anesthetics of 0.223, 0.591, and 0.797 mL.kg-1 could provide sufficient analgesia for localized foot, knee, and hip surgeries, respectively. However, since the required volume of the local anesthetics could not be calculated linearly, the real-time dynamic flow tracking technique for the caudal epidural block is recommended in young pediatric patients.

TRIAL REGISTRATIONS

ClinicalTrials.gov (NCT04039295).

Evaluation of ropivacaine combined with dexmedetomidine versus ropivacaine alone for epidural anesthesia: A meta-analysis

BACKGROUND

Ropivacaine is considered the most commonly used for epidural anesthesia. We compared the efficiency and safety of ropivacaine alone (R group) and ropivacaine combined with dexmedetomidine (RD group).

METHOD

PubMed, the Cochrane Library, Google Scholar, Ovid Medline, the Web of Science, Scopus, Embase, and ScienceDirect were searched. We considered sensory and motor block, duration of anesthesia, time to rescue, hemodynamics, and adverse effects as the primary endpoints.

RESULTS

Eleven randomized controlled trials were included with 337 patients in the R group and 336 patients in the RD group. The RD group had a shorter time to onset of sensory (mean difference [MD]: 3.97 [1.90-6.04] minutes; P = .0002) and motor (MD: 2.43 [0.70-4.16] minutes; P = .006) block and a longer duration of anesthesia (MD: -164.17 [-294.43 to -33.91]; P = .01) than the R group. Comparison of the time to rescue between the groups showed no significant difference (MD: -119.01[-254.47-16.46] minutes; P = 0.09). The R group showed more stable hemodynamics than the RD group in heart rate and arterial pressure at 10 minutes. The R group had a lower incidence of bradycardia and a higher incidence of shivering than the RD group.

CONCLUSION

RD may be a more suitable choice for epidural anesthesia with better anesthetic outcomes than R alone. However, the safety of the combination must be carefully assessed.

Dexmedetomidine and Ketamine as an Adjuvant to Levobupivacaine for Pediatric Caudal Analgesia: A Randomized, Controlled Study

Background:

Ketamine and dexmedetomidine as an adjuvant to caudal block are used in the pediatric population.

Aims:

We aimed to compare the analgesic and safety profile of dexmedetomidine with ketamine for single-shot caudal block.

Settings and Design:

This was a randomized controlled study conducted in a tertiary care university hospital.

Materials and Methods:

Ninety patients admitted for routine infraumbilical surgical procedures under general anesthesia were enrolled in this double-blind randomized study. Following caudal block under general anesthesia, patients were allocated to one of three groups; Group LS received 0.75 mL.kg ^{− 1} levobupivacaine 0.25% diluted in saline 0.9%, Group LK received 0.75 mL.kg ^{− 1} levobupivacaine 0.25% with ketamine 0.5 mg.kg ^{− 1}, and Group LD received 0.75 mL.kg ^{− 1} levobupivacaine 0.25% with dexmedetomidine 1 μg.kg ^{− 1}. Postoperative pain was assessed by the Face, Legs, Activity, Cry, and Consolability (FLACC) score, and the duration of analgesia (time from caudal block to time at which FLACC score 4 or more) was recorded. Hemodynamic parameters and oxygen saturation were also monitored.

Statistical Analysis Used:

Categorical data were analyzed by Chi-squire test and numerical continuous data were analyzed by Student's t-test for comparison between two groups. Mann–Whitney test was used to compare score. One-way analysis of variance was used to compare the means between three groups.

Results:

The addition of dexmedetomidine and ketamine to levobupivacaine resulted in significant prolongation of postoperative analgesia duration (467 min and 385 min, respectively) compared with 0.25% levobupivacaine alone (276 min). No significant side effects requiring intervention were observed in any group.

Conclusions:

Dexmedetomidine as an adjuvant to levobupivacaine provides a longer duration of analgesia as compared to ketamine without any significant side effect.

Dexmedetomidine and Bupivacaine Association in Caudal Epidural Injection in Mares

The objective of the study was to compare the effects of caudal epidural bupivacaine and dexmedetomidine (DEX) combination, with bupivacaine or DEX plain for perineal analgesia in mares. Six healthy saddle mares weighing 330-370 kg and aged 10-15 years were used in this study. Each mare was assigned to receive three treatments: 0.04 mg/kg 0.25% bupivacaine (BP), 2 μg/kg DEX (DX), or 0.02 mg/kg bupivacaine and 1 μg/kg DEX (BPDX). The order of treatments was randomized. All drugs were injected into the caudal epidural space (Co1-Co2) through a 16-G Tuohy epidural needle. After the epidural injections, heart rate, respiratory rate, arterial blood pressures (systolic, diastolic, and mean), and rectal temperature were measured at 5, 10, 15, 30, 60, 90, and 120 minutes, and after this time, every 60 minutes until the end of the experiments. A subjective score system was used to assess analgesia, behavioral and motor blockade at the same time points. The BPDX treatment produced analgesic action with twice the duration (200 minutes) of the BP treatment (97 minutes), but with an analgesic duration shorter than the DX treatment (240 minutes) in the regions of the tail, perineum, and upper hind limbs in mares. All treatments showed mild motor blockade. No behavioral changes were observed in any of the animals. There was hemodynamic stability without significant changes in respiratory rate for all treatments. Epidural analgesia using DEX alone or the combination of DEX and bupivacaine may be an option for painful obstetric and gynecological procedures in mares.

The Efficacy and Safety of Dexmedetomidine Combined with Bupivacaine on Caudal Epidural Block in Children: A Meta-Analysis

BACKGROUND This meta-analysis was conducted to evaluate the analgesics effect and safety of dexmedetomidine (DEX) combined with bupivacaine (BU) on caudal epidural block. MATERIAL AND METHODS Published studies were identified using the PubMed, EMBASE, Web of Science, and the Cochrane Library from inception until October 2017. Relative risk (RR), the standardized mean difference (SMD), and the corresponding 95% confidence interval (CI) were calculated using the STATA 12.0. RESULTS Ten randomized controlled trials (RCTs) were selected for this meta-analysis, involving a total of 691 patients. There was a longer duration of postoperative analgesia in children receiving DEX (SMD=3.19, 95% CI: 2.16-4.22, P<0.001). Furthermore, there was a lower number of patients requiring rescue analgesics in the (BU) + (DEX) group (6 hours: RR=0.09, 95% CI: 0.05-0.17, P<0.001; 12 hours: RR=0.50, 95% CI: 0.32-0.79, P=0.003; 24 hours: RR=0.66, 95% CI: 0.51-0.85, P=0.002). Finally, the occurrence of adverse events, between BU and DEX + BU group, was not statistically significant (RR=0.96, 95% CI: 0.58-1.58, P>0.05). CONCLUSIONS DEX seems to be a promising adjuvant to BU increase duration of caudal analgesia without an increase in side effects in children. However, the result may be influenced by clinical heterogeneity. More large-scale, multicenter, approaching, double-blinded RCTs are required to confirm our results.

Pharmacological advances in the multimodal management of perioperative analgesia

The concept of multimodal analgesia is currently widespread in our clinical practice. The aim of multimodal analgesia is to reduce the side effects derived from the drugs or techniques used for the control of pain together with greater effectiveness (combination of multiple mechanisms of action) with the maximum efficiency, that is, to combine different pharmacodynamics (synergistic or additive effects) and pharmacokinetics, in the context of a predictable acute pain model, thus allowing a prior strategy such as the model of acute postoperative pain. Pain is a complex physiological phenomenon. Postoperative pain involves multiple pathways including nociceptive, inflammatory, and neuropathic sources. In the transmission of pain therefore, different molecules participate, which means that there are multiple pharmacological targets on which to act, and therefore a wide range of drugs to be used following the physiology of pain.