Caudal anesthesia with sedation for inguinal hernia repair in high risk neonates

Awake caudal anesthesia in ex-premature infants undergoing lower abdominal surgery: A narrative review

BACKGROUND AND OBJECTIVES

The aim of this narrative review is to evaluate the literature describing the use of caudal anesthetic-based techniques in premature and ex-premature infants undergoing lower abdominal surgery.

METHODS

All available literature from inception to August 2023 was retrieved according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines from Medline, PubMed, Embase, and the Cochrane Library. Two authors reviewed all references for eligibility, abstracted data, and appraised quality.

RESULTS

Of the 211 articles identified, 45 met our inclusion criteria yielding 1548 cases with awake caudal anesthesia. The review included 558 (36.0%) cases of awake caudal anesthesia, 837 cases (54.1%) of "awake" caudal anesthesia with sedation, and 153 cases (9.9%) of combined spinal caudal epidural anesthesia without sedation. The overall anesthetic failure rate was 7.2% (71.9:1000 caudals). Failure rates were highest for CSEA (13.7%, 7.7-18.4), intermediate for awake caudal (6.6%, 5.26-9.51), and lowest for sedated caudal anesthesia (5.85%, 4.48-7.82). The incidence (range) of perioperative apnea was highest for sedated caudal anesthesia (8.16, 0%-24%), intermediate for awake caudal (7.62%, 0%-60%), and lowest for CSEA (5.53%, 0%-14.3%). High spinal anesthesia occurred in 0.84%, or 8.35:1000 caudals overall. The incidence was highest in awake caudal anesthesia cases (1.97% or 19.7:1000 caudals), intermediate with caudal with sedation (1.07% or 10.7:1000 caudals), and lowest in CSEA (0.7% or 6.6:1000 caudals). Our review was confounded by incomplete data reporting and small sample sizes as most were case reports. There were no high-quality randomized controlled trials, and the eight single-center retrospective data reviews lacked sufficient data to perform meta-analysis.

CONCLUSIONS

There is insufficient evidence to validate or refute the benefits of the use of "awake" caudal anesthesia in premature and ex-premature infants. The high doses of local anesthetics used, the high failure rate, and the increased incidence of high spinal anesthesia would suggest that the techniques offer no real advantages over awake spinal anesthesia or general anesthesia with a regional block.

Cardiovascular Effects of Adding Epinephrine to Bupivacaine in Children Undergoing Caudal Block: A Double-blind Randomized Clinical Trial

Background: Caudal block is a common, safe, and effective anesthetic technique for lower abdominal, urological, and lower extremity surgeries in pediatrics. Objectives: This study aimed to evaluate the cardiovascular effects of adjuvant epinephrine in the caudal block on heart rate and blood pressure changes in children. Methods: This double-blind, randomized clinical trial was performed on 60 children who underwent elective infra-umbilical surgeries. They were under general anesthesia with midazolam, fentanyl, lidocaine, and propofol. The patients were ventilated through laryngeal mask airway (LMA), and anesthesia was maintained with sevoflurane in O2 and N2O mixture. The intervention group received a caudal block with 0.2% bupivacaine and 1/200000 epinephrine (1 mL/kg), while the control group received a caudal block without epinephrine. Heart rate, blood pressure, and ECG were monitored before the block and in the first, fifth, and 20th minutes after surgery. Results: The two groups showed no statistically significant differences in demographics and systolic and diastolic blood pressures. However, sinus arrhythmia was more prevalent in the study group in the first minute after the block (P < 0.001). No differences were observed in the incidence of arrhythmia in the fifth and 20th minutes after the block. Conclusions: It appears that epinephrine as an adjuvant to the caudal block does not have long-lasting effects after the block, except sinus tachycardia in the first minute. Considering that no changes in blood pressure and other hemodynamic parameters were observed, it seems that epinephrine can be used safely in the caudal block in pediatric patients.

Postoperative emergence agitation and intraoperative sevoflurane sedation under caudal block in children: a randomized comparison of two sevoflurane doses

BACKGROUND

Sub-umbilical surgery under caudal block in conjunction with sevoflurane sedation may be safe in terms of maintaining spontaneous breathing and avoiding complications associated with general anesthesia. However, sevoflurane-induced emergence agitation (EA) continues to be a clinically important phenomenon in children. To compare the incidence of EA in children undergoing sub-umbilical surgery under caudal block with two different doses of sevoflurane.

METHODS

Forty children (aged 1-5 years) scheduled to undergo inguinal hernia repair under caudal block with sevoflurane sedation via a face mask were randomized into either the low-dose (1.0%) end-tidal sevoflurane concentration group (Group LS) or the high-dose (2.5%) end-tidal sevoflurane concentration group (Group HS). We monitored EA episodes at 5 and 30 min in the post-anesthetic care unit (PACU) by using the fourpoint agitation scale and the Pediatric Anesthesia Emergence Delirium (PAED) scale.

RESULTS

The four-point agitation scale scores and PAED scores were not different between the groups at 5 min. However, the agitation score was higher in Group HS than in Group LS at 30 min after arriving in the PACU. The time required to recover from sedation was longer in Group HS than in Group LS.

CONCLUSIONS

Face-mask sedation with 1.0% sevoflurane in conjunction with caudal block may be more effective than that with 2.5% sevoflurane in preventing EA.

Clonidine versus other adjuncts added to local anesthetics for pediatric neuraxial blocks: a systematic review and meta-analysis

Background

Clonidine is a common adjunct to local anesthetics for pediatric neuraxial block; however, the pros and cons between clonidine and other adjuncts remain unclear. Thus, we performed this meta-analysis of randomized controlled trials to assess the efficacy and adverse effects between clonidine and other adjuncts added to local anesthetics.

Materials and methods

The systematic search, data extraction, critical appraisal, and pooled analysis were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Randomized controlled studies were searched in Cochrane (to present), Medline (1946 to present), Embase (1974 to present), and Biosis (1995 to present). Relative risks (RRs), standard mean difference (SMD), and associated CIs were calculated using RevMan statistical software to assess continuous and dichotomous data. Heterogeneity in studies was measured by forest plots and I² values. Subgroup analysis was performed for continuous and dichotomous variables, while meta-regression was applied for continuous data with high I² values.

Results

A total of 15 randomized controlled studies met the inclusion criteria. There was a longer duration of postoperative analgesia in the clonidine group than for other adjuncts (SMD=1.54, p=0.005, I²=96%). The number of patients requiring rescue analgesia was lower in the clonidine group without the addition of epinephrine (RR=0.55, p=0.0002, I²=0), while the RR for the comparison with epinephrine was significant (p=0.62, I²=95%). The duration of motor block was longer in the clonidine group (mean difference [MD]=1.06, p<0.00001, I²=0). The clonidine group also had a lower incidence of postoperative nausea and vomiting (PONV; RR=0.49, p<0.00001, I²=0). Postoperative bradycardia, hypotension, and urinary retention were not significantly different between clonidine and other adjuncts (p>0.05).

Conclusion

Clonidine, compared with other adjuncts, added to local anesthetics for neuraxial block, provides a longer duration of postoperative analgesia with lower incidence of PONV. However, the duration of motor block may also be prolonged by clonidine.

Transversus Abdominis Plane Block for Inguinal Hernia Repair in a Premature Infant: A Case Report

In this report, we describe the case of a premature infant (36 weeks' postgestational age) who underwent left inguinal hernia repair under general anesthesia without the use of any airway device. Anesthesia was induced and maintained with sevoflurane in oxygen and nitrous oxide. An ultrasound-guided transversus abdominis plane block was performed that provided effective analgesia, obviating the need for opioids in the intraoperative period. The infant's hemodynamics remained stable throughout the surgery. This report also briefly explains the advantages of using a transversus abdominis plane block, compared with neuraxial blockade, for hernia repair surgery.