Bayesian enhanced meta-analysis of post-operative analgesic efficacy of additives for caudal analgesia in children

Methods of prolonging the effect of caudal block in children

Caudal epidural blockade is one of the most frequently administered regional anesthesia techniques in children. It is a supplement during general anesthesia and for providing postoperative analgesia in pediatrics for sub-umbilical surgeries, especially for genitourinary surgeries. However, the duration of the analgesic effect is occasionally unsatisfactory. In this review, we discuss the main advantages and disadvantages of different techniques to prolong postoperative analgesia for single-injection caudal blockade in children. A literature search of the keywords "caudal", "analgesia", "pediatric", and "children" was performed using PubMed and Web of Science databases. We highlight that analgesic quality correlates substantially with the local anesthetic's type, dose, the timing relationship between caudal block and surgery, caudal catheterization, and administration of epidural opioids or other adjuvant drugs.

Comparison of Caudal Block and Dexmedetomidine Infusion in Pediatric Patients Undergoing Hypospadias Repair Surgery: A Prospective, Randomized, Double-blinded Clinical Study

Background

Many parents continue to reject caudal block since they worry about a rare neurological consequence that may happen. A parenteral surrogate is sought because it can induce recovery with features such as local analgesia.

Objectives

To compare the efficacy and safety of intravenous dexmedetomidine versus caudal and general anesthesia (GA) in children undergoing hypospadias surgery repair.

Methods

A randomized prospective study was conducted on 135 pediatric patients scheduled for hypospadias repair surgery in the hospital affiliated to Tanta University. The participants were divided into a control group (Group C) receiving GA, a caudal group receiving caudal block after GA, and a dexmedetomidine group (Group D) receiving intravenous dexmedetomidine after GA. The postoperative modified objective pain score (MOPS), the total pethidine received in the first 24 h postoperatively, and complications were recorded.

Results

The patients receiving GA required a significantly higher pethidine dose than the other two groups without a significant difference between caudal and dexmedetomidine. The patients receiving dexmedetomidine were extubated significantly later than patients in the other two groups. Regarding the MOPS score, there was a significant difference between Group C and the other two groups 30 minutes and one hour after operation regarding movements, posture, and agitation. Moreover, a significantly larger number of patients developed tachycardia in Group C compared to the other groups.

Conclusions

With the caudal block, the benefits of smooth emergency can be obtained by intravenous dexmedetomidine; however, it had less analgesic efficacy in the pediatric patients undergoing hypospadias repair surgery.

The Assessment of Prolonged Inferior Alveolar Nerve Blockade for Postoperative Analgesia in Mandibular Third Molar Surgery by a Perineural Addition of Dexamethasone to 0.5% Ropivacaine: A Randomized Comparison Study

Background: Perineurally adding dexamethasone to local anesthetics could enable postoperative analgesia. Our aim was to investigate the efficacy of 4 mg dexamethasone and 0.5% ropivacaine on the prolonged duration of mandibular anesthesia for postoperative analgesia during third molar surgery. Materials and method: The patients of both sexes, and in the age range of 17 to 50 yrs of age, received the Gow-Gates anesthesia. Group I received 4 mL of plain 0.5% ropivacaine, with perineurally added 1 mL/4 mg of dexamethasone; group II received 4 mL of plain 0.5% ropivacaine with perineurally added 1 mL of 0.9% saline; group III received 4 mL of plain 0.5 bupivacaine with perineurally added 1 mL of 0.9% saline. The prime anesthesia outcome was the duration of conduction anesthesia (DCA); the secondary outcome was the duration of analgesia (DAN) and analgesia before analgesic intake. Results: In 45 randomly selected subjects (mean age 27.06 ± 8.20), DCA was statistically longest in group I (n = 15) (592.50 ± 161.75 min, p = 0.001), collated with groups II (n = 15) and III (n = 15) (307.40 ± 84.71 and 367.07 ± 170.52 min, respectively). DAN was significantly the longest in group I (mean: 654.9 ± 198.4 min, p = 0.001), compared with group II (345.4 ± 88.0 min) and group III (413.7 ± 152.3 min), with insignificant adverse reactions. One-third of the operated patients absented from the use of analgesics. Conclusion: A amount 0.5% ropivacaine with dexamethasone usefully served as an analgesic with a success rate of 93.4% of the given anesthesia.

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.

When the Safe Alternative Is Not That Safe: Tramadol Prescribing in Children

Children represent a vulnerable population in which management of nociceptive pain is complex. Drug responses in children differ from adults due to age-related differences. Moreover, therapeutic choices are limited by the lack of indication for a number of analgesic drugs due to the challenge of conducting clinical trials in children. Furthermore the assessment of efficacy as well as tolerance may be complicated by children's inability to communicate properly. According to the World Health Organization, weak opioids such as tramadol and codeine, may be used in addition to paracetamol and ibuprofen for moderate nociceptive pain in both children and adults. However, codeine prescription has been restricted for the last 5 years in children because of the risk of fatal overdoses linked to the variable activity of cytochrome P450 (CYP) 2D6 which bioactivates codeine. Even though tramadol has been considered a safe alternative to codeine, it is well established that tramadol pharmacodynamic opioid effects, efficacy and safety, are also largely influenced by CYP2D6 activity. For this reason, the US Food and Drug Administration recently released a boxed warning regarding the use of tramadol in children. To provide safe and effective tramadol prescription in children, a personalized approach, with dose adaptation according to CYP2D6 activity, would certainly be the safest method. We therefore recommend this approach in children requiring chronic or recurrent nociceptive pain treatment with tramadol. In case of acute inpatients nociceptive pain management, prescribing tramadol at the minimal effective dose, in a child appropriate dosage form and after clear instructions are given to the parents, remains reasonable based on current data. In all other situations, morphine should be preferred for moderate to severe nociceptive pain conditions.

Effect of magnesium added to local anesthetics for caudal anesthesia on postoperative pain in pediatric surgical patients: A systematic review and meta-analysis with Trial Sequential Analysis

BACKGROUND

Magnesium has been investigated as an adjuvant for neuraxial anesthesia, but the effect of caudal magnesium on postoperative pain is inconsistent. The aim of this systematic review and meta-analysis was to evaluate the analgesic effect of caudal magnesium.

METHODS

We searched six databases, including trial registration sites. Randomized clinical trials reporting the effect of caudal magnesium on postoperative pain after general anesthesia were eligible. The risk ratio for use of rescue analgesics after surgery was combined using a random-effects model. We also assessed adverse events. The I2 statistic was used to assess heterogeneity. We assessed risk of bias with Cochrane domains. We controlled type I and II errors due to sparse data and repetitive testing with Trial Sequential Analysis. We assessed the quality of evidence with GRADE.

RESULTS

Four randomized controlled trials (247 patients) evaluated the need for rescue analgesics. In all four trials, 50 mg of magnesium was administered with caudal ropivacaine. The results suggested that the need for rescue analgesia was reduced significantly by caudal magnesium administration (risk ratio 0.45; 95% confidence interval 0.24-0.86). There was considerable heterogeneity as indicated by an I2 value of 62.5%. The Trial Sequential Analysis-adjusted confidence interval was 0.04-5.55, indicating that further trials are required. The quality of evidence was very low. The rate of adverse events was comparable between treatment groups.

CONCLUSION

Caudal magnesium may reduce the need for rescue analgesia after surgery, but further randomized clinical trials with a low risk of bias and a low risk of random errors are necessary to assess the effect of caudal magnesium on postoperative pain and adverse events.

TRIAL REGISTRATION

University Hospital Medical Information Network Clinical Trials Registry UMIN000025344.

Caudal Analgesia for Hypospadias in Pediatrics: Comparative Evaluation of Adjuvants Dexamethasone and Dexmedetomidine Combination versus Dexamethasone or Dexmedetomidine to Bupivacaine: A Prospective, Double-Blinded, Randomized Comparative Study

Background:

Caudal block is the most commonly used regional anesthetic technique in pediatric surgeries; different additives have been used for better and safer outcome.

Aim:

The aim of this study is to compare the combination of dexamethasone and dexmedetomidine as adjuvants to bupivacaine versus using each agent solely with bupivacaine in pediatric caudal block as regards their efficiency in pain relief (the duration of postoperative analgesia, first time to request analgesia, and modified objective pain score [MOPS]).

Study Design:

This was a prospective, double-blinded, randomized study.

Patients and Methods:

Patients and Methods: Sixty-three children scheduled for hypospadias surgery wererandomized into three groupsaccording to the adjuvant drug added to caudal bupivacaine : Group I (n = 21): dexamethasone 0.1 mg/kg + 0.5 mg/kg bupivacaine 0.25%, Group II (n = 21): dexmedetomidine0.01 μg/kg + 0.5 mg/kg bupivacaine 0.25% and Group III (n = 21): dexamethasone 0.1 mg/kg + dexmedetomidine 0.01 μg/kg + 0.5 mg/kgbupivacaine 0.25%. Intraoperative and postoperative hemodynamics were recorded. In postoperative anesthesia care unit and then the ward, MOPS and sedation score were recorded at 30 min and 1, 2, 3, 6 and 12 h. Further, the time of first analgesic request and side effects were recorded.

Statistical Analysis:

Categorical data were presented as frequencies (%) and analyzed using Chi-square test. Continuous data were presented as mean (standard deviation) and median (quartiles). Continuous data were analyzed using one-way analysis of variance for single measures and two-way mixed model for repeated measures. Kaplan–Meier analysis was performed for the duration of analgesia.

Results:

In Group III, MOPS was lower than Groups I and II at the study times. Further, Group III had prolonged time for first request of analgesic. Sedation scores were prolonged in Group III and Group II than in Group I. There was a reduction in heart rates in Group III more than Group I and Group II but with no significant difference. However, there was a significant reduction in mean arterial blood pressure 30 min intraoperatively and postoperatively in Group III as compared to Groups I and II.

Conclusion:

The addition of combined dexmedetomidine at a dose of 1 μg/kg and dexamethasone 0.1 mg/kg to caudal bupivacaine seemed to be an attractive alternative to each drug if used alone with more prolonged analgesia and almost no adverse effects.

A study to compare caudal levobupivacaine, tramadol and a combination of both in paediatric inguinal hernia surgeries

Background and Aims:

Caudal block is a safe and simple method of pain relief in young children with the drawback of a short duration of analgesia which can be overcome by adding various adjuvants to the injected local anaesthetic. We compared the effects of caudal levobupivacaine, tramadol and a combination of both in paediatric patients undergoing inguinal herniotomy.

Methods:

A total of 78 children aged 1–7 years, planned for inguinal herniotomy were randomly allocated into three groups. Group L received levobupivacaine 0.125% 1 ml/kg, Group T received tramadol 1.5 mg/kg in 0.9% NS and Group LT 1 ml/kg of 0.125% levobupivacaine with 1.5 mg/kg tramadol caudally. The primary outcome was the duration of analgesia. Rescue analgesic doses required, the duration of motor blockade and adverse effects were recorded for 12 h post-operatively. Data was analysed by analysis of variance test, Kruskal-Wallis and Chi-square tests.

Results:

All groups were comparable with regard to age, sex and duration of surgery. No motor block was observed in any of the patients. The mean duration of analgesia in Group L was 321.46 ± 84.76 min, in Group T was 565.19 ± 107.08 min, and in Group LT was 720 min (P < 0.001). The requirement for rescue analgesia in tramadol group was significantly less as compared to levobupivacaine group. Sedation scores and adverse effects were comparable among all groups.

Conclusion:

Addition of tramadol to caudal levobupivacaine significantly increased the duration of postoperative analgesia.

Effect of an Intravenous Dexamethasone Added to Caudal Local Anesthetics to Improve Postoperative Pain: A Systematic Review and Meta-analysis With Trial Sequential Analysis

BACKGROUND

Caudal anesthesia has been used for postoperative pain control in pediatric surgical patients, but the duration of the analgesic effect is occasionally unsatisfactory. Intravenous steroids have been shown to be effective for postsurgical pain management after certain surgeries. The aim of this meta-analysis with trial sequential analysis (TSA) was to evaluate the analgesic effect of steroids in patients administered with caudal anesthesia.

METHODS

This study was a systematic review and meta-analysis. A search of published literature was conducted in the MEDLINE, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials databases and in trial registration sites. Randomized controlled trials that compared intravenous steroids with a placebo in pediatric patients who had received caudal anesthesia for surgery were included in the study. The primary outcomes from the present meta-analysis were the analgesic duration and the number of patients who required rescue analgesics. The analgesic duration and incidence of rescue use were summarized using mean difference or risk ratio with a 97.5% confidence interval (CI), respectively. If the 97.5% CI of the mean difference or risk ratio included a value of 0 or 1, respectively, we considered the difference not to be significant. We used the random effects model to combine the results. Heterogeneity was quantified with the I statistic. The quality of the trials was evaluated using the Cochrane methodology. Moreover, a TSA with a risk of type 1 error of 2.5% and power of 90% was performed. We established the minimum clinically meaningful difference of analgesic duration as 3 hours. The target sample size for meta-analysis was also calculated in the TSA. We also assessed adverse events.

RESULTS

Six trials with 424 patients were included; 211 patients received intravenous steroids. All trials compared dexamethasone of at least 0.5 mg/kg dose with a placebo. Dexamethasone prolonged the duration of caudal analgesia (mean difference, 244 minutes; 97.5% CI, 188-300). Heterogeneity was considerable with an I value of 94.8%. Quality of evidence was very low. The TSA suggested that only 17.0% of the target sample size had been reached, but the cumulative Z score crossed the trial sequential monitoring boundary to indicate a benefit. Rescue use was reported in 4 studies with 260 patients. Rescue use was not significantly reduced in the dexamethasone group (risk ratio, 0.53; 97.5% CI, 0.09-3.30; I, 98.7%). No increase in adverse events was reported.

CONCLUSIONS

Intravenous dexamethasone prolongs the analgesic duration of caudal anesthesia. Trials to investigate the effectiveness of a lower dose of the dexamethasone in prolonging analgesic effects would be of interest. Further trials with a low risk of bias are necessary.

Epidural analgesia in a paediatric teaching hospital: Trends, developments, and a brief review of literature

Introduction:

Continuous epidural analgesia has proven to be a good tool in the anaesthetist’s quest to provide excellent pain relief for an extended perioperative period. Pharmaceutical advances provide us with a larger array of both local anaesthetic (LA) drugs and additives that can prolong the duration or enhance the quality of analgesia, or both. The avoidance of LA toxicity is of paramount importance for safe prescription, especially in the high-risk neonatal and infant cohort, and all patients stand to benefit from ‘safer’ LA agents and adjuvants that promote the use of a lowered concentration of epidural LA infusions. We present a descriptive review of trends in epidural prescription and technique in our hospital.

Methods:

Our observational study was conducted over a period of 19 years in a tertiary paediatric teaching hospital. Prospectively collected data that included patient demographics, level of epidural catheter insertion, LA drugs and adjuvants used, as well as postoperative infusion rates, were then analysed retrospectively.

Results:

There was a decline in the use of paediatric epidural analgesia. Over the study period, we also observed a shift in preference of LAs and adjuvant drugs toward safer alternatives.

Conclusion:

Paediatric epidural analgesia is gradually being superseded by other analgesic modalities with superior safety profiles (e.g. peripheral neural blockade). However, indications remain for its continued use, and anaesthetists should be familiar with its technical aspects and pitfalls.

Interventions for postoperative pain in children: An overview of systematic reviews

The aim of this study was to conduct an overview of systematic reviews that summarizes the results about efficacy and safety from randomized controlled trials involving the various strategies used for postoperative pain management in children. We searched the Cochrane Database of Systematic Reviews, CINAHL, Database of Reviews of Effect, Embase, MEDLINE, and PsycINFO from the earliest date to January 24, 2016. This overview included 45 systematic reviews that evaluated interventions for postoperative pain in children. Out of 45 systematic reviews that investigated various interventions for postoperative pain in children, 19 systematic reviews (42%) presented conclusive evidence of efficacy. Positive conclusive evidence was reported in 18 systematic reviews (40%) for the efficacy of diclofenac, ketamine, caudal analgesia, dexmedetomidine, music therapy, corticosteroid, epidural analgesia, paracetamol, and/or nonsteroidal anti-inflammatory drugs and transversus abdominis plane block. Only one systematic review reported conclusive evidence of equal efficacy that involved a comparison of dexmedetomidine vs morphine and fentanyl. Safety of interventions was reported as conclusive in 14 systematic reviews (31%), with positive conclusive evidence for dexmedetomidine, corticosteroid, epidural analgesia, transversus abdominis plane block, and clonidine. Seven systematic reviews reported equal conclusive safety for epidural infusion, diclofenac intravenous vs ketamine added to opioid analgesia, bupivacaine, ketamine, paracetamol, and dexmedetomidine vs intravenous infusions of various opioid analgesics, oral suspension and suppository of diclofenac, only opioid, normal saline, no treatment, placebo, and midazolam. Negative conclusive statement for safety was reported in one systematic review for caudal analgesia vs noncaudal regional analgesia. More than half of systematic reviews included in this overview were rated as having medium methodological quality. Of 45 included systematic reviews, 10 were Cochrane reviews and they had higher methodological quality than non-Cochrane reviews. As evidence concerning efficacy and safety is inconclusive for most of the analyzed interventions, our review points out the need for more rigorous trials concerning pain management in children.

Evaluation of caudal dexamethasone with ropivacaine for post-operative analgesia in paediatric herniotomies: A randomised controlled study

Background and Aims:

Caudal analgesia is one of the most popular regional blocks in paediatric patients undergoing infra-umbilical surgeries but with the drawback of short duration of action after single shot local anaesthetic injection. We evaluated whether caudal dexamethasone 0.1 mg/kg as an adjuvant to the ropivacaine improved analgesic efficacy after paediatric herniotomies.

Methods:

Totally 128 patients of 1–5 years age group, American Society of Anaesthesiologists physical status I and II undergoing elective inguinal herniotomy were randomly allocated to two groups in double-blind manner. Group A received 1 ml/kg of 0.2% ropivacaine caudally and Group B received 1 ml/kg of 0.2% ropivacaine, in which 0.1 mg/kg dexamethasone was added for caudal analgesia. Post operative pain by faces, legs, activity, cry and consolability tool score, rescue analgesic requirement and adverse effects were noted for 24 h.

Results:

Results were statistically analysed using Student's t-test. Pain scores measured at 1, 2, 4, and 6 h post-operative, were lower in Group B as compared to Group A. Mean duration of analgesia in Group A was 248.4 ± 54.1 min and in Group B was 478.046 ± 104.57 min with P = 0.001. Rescue analgesic requirement was more in Group A as compared to Group B. Adverse effects after surgery were comparable between the two groups.

Conclusion:

Caudal dexamethasone added to ropivacaine is a good alternative to prolong post-operative analgesia with less pain score compared to caudal ropivacaine alone.

Alpha-2 adrenoceptor agonists as adjuncts to peripheral nerve blocks in children: a meta-analysis

BACKGROUND

Adult meta-analyses have verified that adjunct use of alpha-2 adrenoceptor agonists (A2AA) together with local anesthetics (LA) will prolong the duration of peripheral nerve blocks. The standard use of A2AAs for peripheral nerve blockade has recently been recommended also in children, but the evidence base in support of this suggestion has to date been equivocal. The purpose of this meta-analysis was to produce evidence-based data regarding the effect in children.

METHODS

Following a thorough literature search, five randomized controlled trials were included in a meta-analysis. Raw data from all studies were gathered and aggregated into patients randomized to receive plain LA (Group PLA) or LA mixed with either adjunct clonidine or dexmedetomidine (Group ADJ). The main outcome parameter was block duration (time to first administration of supplemental analgesic based on predetermined pain scores) analyzed by survival statistics. The total number of supplemental analgesic doses during the first 24 postoperative hours and serious side effects were included as secondary outcomes.

RESULTS

Pooling of the study data generated 141 patients in Group PLA and 142 patients in Group ADJ (overall n = 283; age: 0.8-13 years; weight 8-47 kg). Block duration was significantly prolonged (9.75 h vs 3.75 h) compared to the use of plain LA. Survival statistics verified a beneficial effect of using adjunct A2AAs [the log rank (Mantel-Cox) test (P = 0.0078), Gehan-Breslow-Wilcoxon test (P = 0.0027), and hazard ratio (1.653; 95% CI: 1.142 to 2.395)]. The number of patients that needed ≥ 2 doses of supplemental analgesics was higher in Group PLA (n = 19) compared to Group ADJ (n = 6) (P = 0.0088). No serious side effects were reported.

CONCLUSION

This meta-analysis provides evidence-based support for the use of adjunct alpha-2 adrenoceptor agonists when performing peripheral nerve blocks in children.

Is the pharmacokinetics of bupivacaine equivalent after lumbar epidural administration through a needle or a catheter in male and female adults?

We assessed possible pharmacokinetic modifications due to different epidural injection techniques using either a needle or a catheter. Adult patients (n=23) undergoing lower abdominal or lower extremity surgery were randomly assigned a single bupivacaine epidural injection anesthesia (0.5%, 15 mL, 0.3 mL/s) through needle or catheter device. Plasma bupivacaine concentration was quantified using a validated HPLC method and non-compartmental pharmacokinetic parameters estimated. CMAX and TMAX were similar in both groups: 952 ± 346 ng/mL, 0.65 ± 0.5 1h in the needle group; 810 ± 307 ng/mL, 0.43 ± 0.29 h in the catheter group respectively. Plasma AUC₀→∞ was also similar in both groups: 3868 ± 1687 ngh/mL for needle versus 4096 ± 1748 ngh/mL using catheter. The catheter group showed slower disposition than the needle group: t₁/₂=3.9 ± 2.3 h, MRT=6.0 ± 3.1 h versus 2.7 ± 1.03 h and 4.5 ± 1.2 h with needle administration respectively though it did not reach statistical significance, Cl/F and V/F were also similar. Lastly, female patients showed significant longer t1/2 after administration through catheter (5.7 ± 2.0 h) than needle (2.7 ± 0.6 h) group (P=0.0279). The device type does not affect the pharmacokinetics which is similar in both groups although sex-based differences might exist.

Adjuncts should always be used in pediatric regional anesthesia

A number of different adjuncts to local anesthetics can be used to prolong and optimize postoperative pain relief following regional anesthesia in children. The present text provides a slightly opinionated but evidence-based argument in favor of this practice.

Magnesium as an adjuvant for caudal analgesia in children

BACKGROUND

There is a need for an adjuvant agent of caudal block that prolongs its duration and improves the analgesic efficacy to fasten functional recovery. Magnesium is an N-methyl-D-aspartate receptor antagonist that functions as an analgesic. This study was aimed to evaluate whether magnesium as an adjuvant for caudal block in children can improve postoperative analgesia and functional recovery.

METHODS

Eighty children, 2-6 years of age, undergoing inguinal herniorrhaphy, were included in this prospective, randomized, double-blinded study. For caudal block, Group R received ropivacaine 1.5 mg·ml(-1), 1 ml·kg(-1) and Group RM received the same dose of ropivacaine mixed with 50 mg of magnesium. The Parents' Postoperative Pain Measure (PPPM) score, analgesic consumption, functional recovery, and adverse effects were evaluated at 6, 24, 48, and 72 h after surgery, as well as daily thereafter until the child showed full functional recovery.

RESULTS

The PPPM score after hospital discharge was significantly lower for Group RM than for Group R at all times (P < 0.05). Children in Group RM required less fentanyl for rescue analgesia in the recovery area (16.2% vs 39.5%, P = 0.034) and less oral analgesics after discharge (20.5% vs 52.6%, P = 0.007). The time to return of normal functional activity was shorter in Group RM (P < 0.05). The incidence of adverse effects did not differ between groups.

CONCLUSIONS

As an adjuvant for caudal analgesia, 50 mg magnesium provided superior quality of analgesia and faster return of normal functional activity than local anesthetic alone in children.

Adjuvants in pediatric regional anesthesia

SUMMARY Local anesthetics have a limited duration of action. Adjuvants are used to prolong the duration of action and to augment analgesia allowing lower concentrations of local anesthetic to be used. Adjuvants have been used more extensively with neuraxial blocks, particularly caudal epidural blocks, but more recently to supplement peripheral nerve blocks. Intrathecal adjuvants are not covered in this review since spinal anesthesia is not widely used in children except in ex-premature infants. Morphine is the historical gold-standard with which other adjuvants are compared. Clonidine is most useful and is becoming increasingly popular, while the side-effect profile of other agents reduces their utility. Concerns with regard to the neurotoxicity of ketamine in animal models has led to its withdrawal in some countries.

Analgesic efficacy of caudal dexamethasone combined with ropivacaine in children undergoing orchiopexy

BACKGROUND

Epidural administration of dexamethasone might reduce postoperative pain in adults. We evaluated whether a caudal block of 0.1 mg kg(-1) dexamethasone combined with ropivacaine improves analgesic efficacy in children undergoing day-case orchiopexy.

METHODS

This randomized, double-blind study included 80 children aged 6 months to 5 yr who underwent day-case, unilateral orchiopexy. Patients received either 1.5 ml kg(-1) of 0.15% ropivacaine (Group C) or 1.5 ml kg(-1) of 0.15% ropivacaine in which dexamethasone of 0.1 mg kg(-1) was mixed (Group D) for caudal analgesia. Postoperative pain scores, rescue analgesic consumption, and side-effects were evaluated 48 h after operation.

RESULTS

Postoperative pain scores at 6 and 24 h post-surgery were significantly lower in Group D than in Group C. Furthermore, the number of subjects who remained pain free up to 48 h after operation was significantly greater in Group D [19 of 38 (50%)] than in Group C [four of 37 (10.8%); P<0.001]. The number of subjects who received oral analgesic was significantly lower in Group D [11 of 38 (28.9%)] than in Group C [20 of 37 (54.1%); P=0.027]. Time to first oral analgesic administration after surgery was also significantly longer in Group D than in Group C (P=0.014). Adverse events after surgery including vomiting, fever, wound infection, and wound dehiscence were comparable between the two groups.

CONCLUSIONS

The addition of dexamethasone 0.1 mg kg(-1) to ropivacaine for caudal block can significantly improve analgesic efficacy in children undergoing orchiopexy. Clinical trial registration NCT01604915.

Neuraxial analgesia in neonates and infants: a review of clinical and preclinical strategies for the development of safety and efficacy data

Neuraxial drugs provide robust pain control, have the potential to improve outcomes, and are an important component of the perioperative care of children. Opioids or clonidine improves analgesia when added to perioperative epidural infusions; analgesia is significantly prolonged by the addition of clonidine, ketamine, neostigmine, or tramadol to single-shot caudal injections of local anesthetic; and neonatal intrathecal anesthesia/analgesia is increasing in some centers. However, it is difficult to determine the relative risk-benefit of different techniques and drugs without detailed and sensitive data related to analgesia requirements, side effects, and follow-up. Current data related to benefits and complications in neonates and infants are summarized, but variability in current neuraxial drug use reflects the relative lack of high-quality evidence. Recent preclinical reports of adverse effects of general anesthetics on the developing brain have increased awareness of the potential benefit of neuraxial anesthesia/analgesia to avoid or reduce general anesthetic dose requirements. However, the developing spinal cord is also vulnerable to drug-related toxicity, and although there are well-established preclinical models and criteria for assessing spinal cord toxicity in adult animals, until recently there had been no systematic evaluation during early life. Therefore, in the second half of this review, we present preclinical data evaluating age-dependent changes in the pharmacodynamic response to different spinal analgesics, and recent studies evaluating spinal toxicity in specific developmental models. Finally, we advocate use of neuraxial drugs with the widest demonstrable safety margin and suggest minimum standards for preclinical evaluation before adoption of new analgesics or preparations into routine clinical practice.