A survey of pediatric caudal extradural anesthesia practice

Ultrasound guided quadratus lumborum block versus interlaminar epidural block for analgesia in pediatric abdominal surgery: a randomized controlled trial

BACKGROUND

Although the efficacy and safety of epidural block (EB) are fairly high, complications such as inadvertent dural puncture may limit its use. Ultrasound-guided quadratus lumborum block (QLB) is a relatively new regional technique that provides perioperative somatic and visceral analgesia for pediatric patients. This trial compared the quality of pain relief in pediatric patients undergoing abdominal surgery who received either QLB or EB.

METHODS

Patients were randomly allocated into two equal groups: Group E(n = 29): received EB; Group QL(n = 29): received QLB. Both groups were injected with 0.25% bupivacaine (0.5 ml/kg). Assessment of total analgesia consumption was the primary outcome measure, whereas the secondary outcome measures were assessment of postoperative analgesic effect by Children's Hospital of Eastern Ontario Pain Scale (CHEOPS) and time of first analgesic request.

RESULTS

Our study showed that the mean total fentanyl consumption was comparable between both groups(38.67 ± 5.02 and 36.47 ± 5.13 µg in the E and QL groups, respectively, P = 0.246). Only five patients did not require rescue analgesia (3 in the E group,2 in the QL group, P = 0.378). The mean duration of analgesia showed no significant difference between the two groups (9.9 ± 1.58 and 11.02 ± 1.74 h in the E and QL groups, respectively, P = 0.212). Evaluation of CHEOPS score values immediately in PACU and for the initial 24 h following operation showed no significant difference between the two study groups(P > 0.05).

CONCLUSION

QLB can achieve analgesic effects comparable to those of EB as a crucial part of multimodal analgesia in children undergoing abdominal surgeries.

CLINICAL TRIAL REGISTRATION NUMBER

PACTR202203906027106.

Transversus abdominis plane block versus caudal block with bupivacaine and dexmedetomidine for unilateral inguinal hernia repair in pediatric patients: a randomized clinical trial

BACKGROUND

This study compared the transversus abdominis plane (TAP) block with bupivacaine and dexmedetomidine to the same mixture in the caudal block in delivering postoperative analgesia in children after unilateral inguinal hernia surgery.

METHODS

The current study included 80 children aged two to eight years who were scheduled for unilateral inguinal hernia surgery under general anesthesia. A caudal block (1 mL/kg 0.25% bupivacaine and one µg /kg dexmedetomidine) or a TAP block (1 mL/kg 0.25% bupivacaine and one µg /kg dexmedetomidine) was given to each participant at random. The time it took to request analgesia for the first time, the postoperative pain score, total analgesic use, sedation, family satisfaction, and side effects were all measured. The primary outcome was time to first analgesic request.

RESULTS

The caudal block group had a considerably shorter time to first analgesic request than the TAP block group. The caudal block group received more rescue analgesia doses within 24 hours than the TAP block group. The mean total dose of intravenous paracetamol within the first 24 hours postoperatively was greater in the caudal block group. The caudal block group had much higher family satisfaction.

CONCLUSIONS

The TAP block and caudal block provide good postoperative analgesia in children undergoing unilateral inguinal hernia repair. Adding dexmedetomidine to the TAP block was superior to the caudal block in terms of extending the length of the initial analgesic request, lowering analgesic requirement, and lowering pain scores without causing substantial adverse effects.

Caudal block vs. transversus abdominis plane block for pediatric surgery: a systematic review and meta-analysis

Background

The caudal block and transversus abdominis plane block (TAP) are commonly used in combination with general anesthesia for pediatric lower abdominal, inguinal, and genitourinary surgeries. There is limited data directly comparing the impact of these techniques on recovery. In this meta-analysis, we compare the duration of postoperative analgesia between these two techniques.

Objective

This review examined the duration of analgesia in pediatric patients (age 0-18 years) undergoing surgery who received caudal or TAP block after induction of general anesthesia. The primary outcome was duration of analgesia, defined as the time to first rescue analgesic dose. Secondary outcomes included number of rescue analgesic doses, acetaminophen usage within 24 h postoperatively, 24 h pain score area under the curve, and postoperative nausea and vomiting.

Evidence review

We systematically searched Pubmed, Central, EMBASE, CINAHL, Google Scholar, Web of Science citation index, the US clinical trials register, and abstracts from prominent 2020-2022 anesthesia conferences for randomized controlled trials that compared these blocks and reported analgesia duration.

Findings

Twelve RCTs inclusive of 825 patients were identified. TAP block was associated with longer analgesia duration (Mean difference = 1.76 h, 95% CI: 0.70-2.81, p = 0.001) and reduced doses of rescue analgesic within 24 h (Mean difference = 0.50 doses, 95% CI: 0.02-0.98, p = 0.04). No statistically significant differences were detected in other outcomes.

Conclusion

This meta-analysis suggests that TAP block provides greater duration of analgesia than caudal block after pediatric surgeries. TAP block was also associated with fewer rescue analgesic doses in the first 24 h without increased pain scores.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=380876, identifier: CRD42022380876.

Postoperative analgesic effects of the quadratus lumborum block III and transversalis fascia plane block in paediatric patients with developmental dysplasia of the hip undergoing open reduction surgeries: a double-blinded randomised controlled trial

OBJECTIVE

To evaluate the analgesic effectiveness of two novel regional nerve blocks in paediatric patients with developmental dysplasia of the hip (DDH) after open reduction surgeries.

DESIGN

Prospective, double-blinded, randomised controlled trial.

SETTING

2 tertiary teaching hospitals in China between August 2017 and July 2018.

PARTICIPANTS

110 paediatric patients aged 2-10 years with DDH undergoing open reduction surgeries were recruited, 95 were randomised and 90 were included in the final analysis.

INTERVENTIONS

Random assignment to quadratus lumborum block III (QLB III) group, transversalis fascia plane block (TFPB) group and the control (no region nerve block) group.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was the Face, Legs, Activity, Cry and Consolability (FLACC) Scale Scores. Secondary outcomes included perioperative opioid consumption, the time until first press of nurse-controlled analgesia/patient-controlled analgesia (NCA/PCA) pump and the total counts number of pressing, length of postanaesthesia care unit (PACU) stay, length of hospital stay, parental satisfaction with pain management and adverse events.

RESULTS

Mean FLACC Scores were significantly lower in QLB III group and TFPB group while in the PACU and for 48 hours postoperatively, compared with control group (p<0.0001, p<0.0001, respectively). No differences were found for FLACC Scores between QLB III group and TFPB group, neither at rest (p=0.0402) nor while posture changing (p=0.0306). TFPB prolonged the first-time request for NCA/PCA analgesia, and decreased the total number of pressing counts, compared with QLB III (22.5 (16.2 to 28.7) vs 11.7 (6.6 to 16.8), p<0.0001; 2.4 (1.3 to 3.6) vs 3.8 (2.8 to 4.8), p=0.0111, respectively). No patient experienced any adverse events.

CONCLUSIONS

We suggested that both ultrasound-guided QLB III and TFPB should be considered as an option for perioperative analgesia in children with DDH undergoing open reduction surgeries. TFPB was superior to the QLB III because it prolonged the first-time request for NCA/PCA analgesia and decreased the total counts number of pressing.

TRIAL REGISTRATION NUMBER

NCT03189966/2017.

Effect of caudal ketamine on minimum local anesthetic concentration of ropivacaine in children: a prospective randomized trial

Background

Caudal ketamine has been shown to provide an effective and prolonged post-operative analgesia with few adverse effects. However, the effect of caudal ketamine on the minimum local anesthetic concentration (MLAC) of ropivacaine for intra-operative analgesia is unclear.

Methods

One hundred and sixty-nine children were randomized to five groups: Group C (caudal ropivacaine only), Group K_0.25 (caudal ropivacaine plus 0.25 mg/kg ketamine), Group K_0.5 (caudal ropivacaine plus 0.5 mg/kg ketamine), Group K_0.75 (caudal ropivacaine plus 0.75 mg/kg ketamine), and Group K_1.0 (caudal ropivacaine plus 1.0 mg/kg ketamine). The primary outcome was the MLAC values of ropivacaine with/without ketamine for caudal block.

Results

The MLAC values of ropivacaine were 0.128% (0.028%) in the control group, 0.112% (0.021%) in Group K_0.25, 0.112% (0.018%) in Group K_0.5, 0.110% (0.019%) in Group K_0.75, and 0.110% (0.020%) in Group K_1.0. There were no significant differences among the five groups for the MLAC values (p = 0.11). During the post-operative period the mean durations of analgesia were 270, 381, 430, 494, and 591 min in the control, K_0.25, K_{0. 5}, K_0.75, and K_1.0 groups respectively, which shown that control group is significantly different from all ketamine groups. Also there were significant differences between K_0.25 and K_0.75 groups, and between K_1.0 groups and the other ketamine groups.

Conclusions

Adding caudal ketamine to ropivacaine prolong the duration of post-operative analgesia; however, it does not decrease the MLAC of caudal ropivacaine for intra-operative analgesia in children.

Clinical trial registration

ChiCTR-TRC-13003492. Registered on 13 August 2013.

Comparison of ultrasound-guided transversus abdominis plane block, quadratus lumborum block, and caudal epidural block for perioperative analgesia in pediatric lower abdominal surgery

Background/aim

Despite different regional anesthesia techniques used to provide intraoperative and postoperative analgesia in pediatric patients, the analgesic effectiveness of peripheral nerve blockades with minimal side effect profiles have not yet been fully determined. We aimed to compare the efficacy of ultrasound-guided transversus abdominis plane (TAP) block, quadratus lumborum (QL) block, and caudal epidural block on perioperative analgesia in pediatric patients aged between 6 months and 14 years who underwent elective unilateral lower abdominal wall surgery.

Materials and methods

Ninety-four patients classified under the American Society of Anesthesiologists physical status classification system as ASA I or ASA II were randomly divided into 3 equal groups to perform TAP, QL or Caudal epidural block using 0.25% of bupivacaine solution (0.5 ml kg−1).

Results

Postoperative analgesic consumption was highest in the TAP block group (P < 0.05). In the QL block group, Pediatric Objective Pain Scale (POAS) scores were statistically significantly lower after 2 and 4 h (P < 0.05). The length of hospital stay was significantly longer in the caudal block group than the QL block group (P < 0.05).

Conclusion

We suggest that analgesia with ultrasound-guided QL block should be considered as an option for perioperative analgesia in pediatric patients undergoing lower abdominal surgery if the expertise and equipment are available.

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.

Postoperative analgesia in children: A comparison of three different doses of caudal epidural morphine

Background and Aims:

Caudal epidural block is the most commonly used neuraxial block in children. Morphine has been used as a caudal additive for more than three decades. The aim of our study was to evaluate the efficacy and duration of analgesia of three different doses of caudal epidural morphine (CEM), and to find out the incidence of side effects.

Material and Methods:

This study was conducted on 75 patients of American Society of Anesthesiologists grades I and II, aged 2-12 years, undergoing lower abdominal and urogenital surgeries. Patients were randomly allocated to one of the three groups according to the dose of morphine. Group I received 30 μg/kg, group II 50 μg/kg, and group III 70 μg/kg. Heart rate, blood pressure, oxygen saturation, electrocardiogram, pain score, sedation score, duration of analgesia, and side-effects were noted.

Results:

The mean duration of analgesia was 8.63 h in group I, 13.36 h in group II and 19.19 h in group III. Respiratory depression was noted in three patients in group III. One patient in group I had itching. One patient each in groups I, II, and III had nausea/vomiting.

Conclusion:

CEM significantly prolongs the duration of analgesia, though with a higher dose the risk of respiratory depression should always be kept in mind.

Analgesic effect and adverse events of dexmedetomidine as additive for pediatric caudal anesthesia: a meta-analysis

BACKGROUND

Dexmedetomidine has become a popular additive for regional anesthesia. Aim of this meta-analysis was to assess the effect of this additive on the duration of postoperative analgesia and possible adverse events in pediatrics undergoing orchidopexy or lower abdominal surgery.

METHODS

The literature databases of PubMed, Google Scholar, and Cochrane Library were searched for randomized, controlled trials (RCTs). Odds ratio (OR), weighted mean difference (WMD), and the corresponding 95% confidence intervals (CIs) were calculated using the RevMan software, version 5.2, for data synthesis and statistical analysis, which in accordance with the PRISMA statement.

RESULTS

Six RCTs were selected for this meta-analysis, involving a total of 328 pediatric patients. There was a significant longer duration of caudal analgesia (time to first analgesic requirements) in patients receiving dexmedetomidine with CA compared with CA alone (WMD: -8.21 h; 95% CI: -11.40 to -5.02; P < 0.00001). Side effects in these two groups were comparable (OR: 1.02; 95% CI: 0.51-2.04; P = 0.95). Subgroup analysis indicated there was no significant difference in hemodynamic changes during operation (WMD: 1.78; 95% CI: -3.20 to 6.77; P = 0.48) and the emergence time (time from the end of surgery to opening the eyes on calling) after surgery (WMD: 0.47 min; 95% CI: -5.27 to 6.22; P = 0.87).

CONCLUSIONS

Dexmedetomidine as an additive to local anesthetic provides a significantly longer postoperative analgesia with comparable adverse effects and hemodynamic changes, when compared to local anesthetics alone. There were insufficient data of the effects of different concentrations of dexmedetomidine; further studies are required to explore this issue.

A comparative study of the effect of caudal dexmedetomidine versus morphine added to bupivacaine in pediatric infra-umbilical surgery

BACKGROUND

One of the most commonly used regional anesthetic techniques in pediatric surgeries is the caudal epidural block. Its main disadvantage remains the short duration of action. Hence, different additives have been used. Dexmedetomidine is a potent as well as highly selective α2 adrenergic receptor agonist. The aim of this randomized, double-blinded, study was to compare the duration of postoperative analgesia of caudal dexmedetomidine versus morphine in combination with bupivacaine in pediatric patients undergoing lower abdominal or perineal surgery.

PATIENTS AND METHODS

A total of 50 pediatric patients 1-5 years old The American Society of Anesthesiologists status I, II scheduled for lower abdominal and perineal surgeries were included in the study. The patients were enrolled into 2 equal groups: Group A patients (n = 25) received dexmedetomidine with bupivacaine while Group B patients (n = 25) received morphine with bupivacaine. Patients were placed in a supine position then inhalational general anesthesia was induced, and laryngeal mask airway (LMA) was placed. Patients were then given caudal epidural analgesia. By the end of surgery reversal of muscle relaxation was done and the LMA was removed. Post-operatively, the sedation as well as pain score were observed and recorded.

RESULTS

The current study showed that minor complications were recorded in the post-anesthesia care unit; in addition, significantly longer periods of analgesia and sedation were detected in Group A. However, no significant differences in demographic data, as well as in the duration of surgery, and the time of emergence from anesthesia and patient condition during recovery were detected.

CONCLUSION

The present study suggested that use of dexmedetomidine, during single dose injection, as an additive to the local anesthetic bupivacaine in caudal epidural analgesia prolongs the duration of post-operative analgesia following lower abdominal as well as perineal surgery compared with caudal morphine with no side-effects on the vital signs. Postoperative side effects were seen with caudal morphine injection rather than with dexmedetomidine.

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.

Perioperative epidural analgesia in children undergoing major abdominal tumor surgery--a single center experience

PURPOSE

The purpose of this study was to assess the use of continuous epidural analgesia in pediatric patients undergoing major abdominal tumor surgery.

METHODS

Children undergoing major abdominal tumor surgery at our institution between 2008 and 2012 (n=40) received continuous epidural analgesia via an epidural catheter. Surgical trauma scores, pain scores, and clinical data of the children were compared to a pair-matched historical control group operated on between 2002 and 2007 without epidural analgesia.

RESULTS

Pain levels in the study group on day 1 and 3 after surgery were lower compared to the control group. The differences did, however, not reach statistical significance (p=0.15 and 0.09). Children in the study group received significantly fewer additional doses of piritramide or morphine (45% versus 82%, p<0.001). Despite significantly higher surgical trauma scores in the study group (p=0.018), there were no statistical differences regarding clinical parameters, such as mechanical ventilation time, time on intensive care unit, and total hospital stay. There were no catheter-related complications.

CONCLUSIONS

Continuous epidural analgesia is beneficial for children undergoing complex abdominal tumor surgery with regard to pain levels, postoperative recovery, and general clinical course. Expertise of the managing team, a careful patient selection, and a continuous quality assessment are essential for success.

Caudal dexmedetomidine decreases the required concentration of levobupivacaine for caudal block in pediatric patients: a randomized trial

BACKGROUND AND OBJECTIVES

Dexmedetomidine (D) can prolong the duration of local anesthetics, but the effect of caudal dexmedetomidine on the potency of levobupivacaine (L) for caudal block has not been investigated. This study was designed to determine the effect of caudal dexmedetomidine on levobupivacaine for caudal block in pediatric patients.

METHODS

Eighty-nine children scheduled for elective inguinal hernia repair or hydrocele were randomly assigned to one of the three groups: Group L (caudal levobupivacaine), Group LD1 (levobupivacaine plus 1 μg·kg(-1) dexmedetomidine), or Group LD2 (levobupivacaine plus 2 μg·kg(-1) dexmedetomidine). The primary endpoint was the minimum local anesthetic concentration (MLAC), which was determined using the Dixon up-and-down method. The secondary endpoints were the duration of analgesia and sedation.

RESULTS

The MLAC values (sd) of caudal levobupivacaine were 0.103 (0.01)%, 0.068 (0.02)%, and 0.055 (0.03)% in Groups L, LD1, and LD2, respectively. The values of EC50 and EC95 (95% CI) of caudal levobupivacaine from logistic regression analysis were 0.094 (0.083-0.105)% and 0.129 (0.1-0.159)%, 0.058 (0.044-0.072)% and 0.106 (0.067-0.144)%, and 0.046 (0.033-0.059)% and 0.091 (0.055-0.127)% in Groups L, LD1, and LD2, respectively. The mean durations of analgesia in the postoperative period were 141, 378, and 412 min in Groups L, LD1, and LD2, respectively (L vs LD1 or LD2, P < 0.001). The mean durations of sedation in both Groups LD1 and LD2 also were significantly prolonged, compared with Group L (P < 0.01).

CONCLUSIONS

Caudal dexmedetomidine reduces the MLAC values of levobupivacaine and improves postoperative analgesia in children without any neurological side effects.

A survey of aseptic precautions and needle type for paediatric caudal block in Australia and New Zealand

This cross-sectional survey was designed to evaluate the current practice of anaesthetists in Australia and New Zealand with regard to aseptic technique and needle type during the performance of single-shot caudal blocks. Professional bodies suggest that full aseptic precautions be taken during the administration of caudal or epidural blocks. It has been suggested that using an intravenous cannula or a styletted needle may obviate the occurrence of epidermoid tumours. A total of 202 members of the Society for Paediatric Anaesthesia in New Zealand and Australia were invited to participate in this internet-based survey. Eighty-four responses were received. Most respondents used some form of antiseptic handwash (81%), wore sterile gloves (85.7%), used antiseptic skin preparation (100%) and draped the site (57.1%). When performing caudal blocks, 43.1% used unstyletted needles, 27.2% used styletted spinal needles and 29.6% used intravenous cannulas. However, 11.9% did not wash hands, 10.7% did not wear gloves and 42.9% did not drape the site. Three respondents reported neither handwashing, wearing gloves or draping, instead only using an alcohol swab for skin preparation. The majority of respondents in our region appear to use some level of aseptic precautions, albeit to a variable degree. Published recommendations may either be perceived as overly cautious or as ambiguous in that they do not specify caudal practice as distinct from other epidural blocks. There is a need for clearer professional guidance to support a minimum level of aseptic precaution for single-shot caudal epidural blocks.

[Pediatric caudal anesthesia : importance and aspects of safety concerns]

Caudal block is a safe procedure commonly used for pediatric perioperative analgesia. Complications are extremely rare but nevertheless local and systemic contraindications must be excluded. Optimal safety and quality result when strict attention is paid to technical details. These are discussed in detail in this review. A local anesthetic (LA) containing epinephrine allows early detection of inadvertent intravascular LA administration; therefore an epinephrine/LA mixture is recommended at least for the test dose. In terms of safety the choice of LA itself is probably of secondary importance. Clonidine as an adjuvant has an excellent risk/benefit profile with minimal side effects. Inadvertent systemic LA intoxication is a rare but potentially fatal complication of regional anesthesia and measures for prevention and early detection are essential. Should circulatory arrest occur, immediate resuscitation following standard guidelines is to be initiated including the use of epinephrine as the first line drug. Intravenous administration of lipid solutions may be beneficial as a secondary adjunct to stabilize hemodynamics but is not an alternative to epinephrine.

[Pediatric caudal anesthesia: importance and aspects of safety concerns]

Caudal block is a safe procedure commonly used for pediatric perioperative analgesia. Complications are extremely rare but nevertheless local and systemic contraindications must be excluded. Optimal safety and quality result when strict attention is paid to technical details. A local anesthetic (LA) containing epinephrine allows early detection of inadvertent intravascular LA administration; therefore an epinephrine/LA mixture is recommended at least for the test dose. In terms of safety the choice of LA itself is probably of secondary importance. Clonidine as an adjuvant has an excellent risk/benefit profile with minimal side effects. Inadvertent systemic LA intoxication is a rare but potentially fatal complication of regional anesthesia and measures for prevention and early detection are essential. Should circulatory arrest occur, immediate resuscitation following standard guidelines is to be initiated including the use of epinephrine as the first line drug. Intravenous administration of lipid solutions may be beneficial as a secondary adjunct to stabilize hemodynamics but is not an alternative to epinephrine.

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

BACKGROUND

The authors calculated the effect size for post-operative analgesia of three additives, clonidine, neostigmine, and tramadol to bupivacaine, ropivacaine, or levobupivacaine used for single-dose caudal extradural blockade in children.

METHODS

A meta-analysis was performed for three end points of efficacy: the increase of time until administration of analgesic drugs, the proportion of patients requiring analgesic drugs during the initial 24 post-operative hours, and the amounts of post-operative analgesic drugs. A Bayesian inference supporting direct statements about the probability of the magnitude of an effect was used to compare the effects size.

RESULTS

Neostigmine increased the duration of analgesia by 9.96 h (95% confidence interval: 7.75 to 12.16), as compared with 3.68 h (2.65 to 4.7) with clonidine and 4.45 (2.84 to 6.07) with tramadol. There is a 95% probability that neostigmine increases the duration of post-operative analgesia by more than 8 h, clonidine by more than 2.8 h, and tramadol by more than 3.25 h, as compared with local anesthetics alone. The odds ratios for the proportion of patients requiring analgesic drugs were 0.22 [0.13 to 0.37] for clonidine and 0.28 [0.10 to 0.75] for neostigmine. With tramadol, there was no statistically significant difference. All three additives reduced the amounts of post-operative analgesic drugs. Neostigmine and tramadol increase the probability for post-operative nausea or vomiting (PONV).

CONCLUSIONS

Neostigmine provides the longest post-operative analgesia. With clonidine, the duration of analgesia is shorter and sedation is increased, but the probability for PONV could be decreased.

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.

Intrathecal clonidine in the neonatal rat: dose-dependent analgesia and evaluation of spinal apoptosis and toxicity

BACKGROUND

Neuraxial clonidine is used for perioperative analgesia in children of all ages. Preclinical studies in the postnatal rat allow comparison of the relative toxicity and safety of spinal analgesics throughout postnatal development.

METHODS

Rat pups aged 3, 7, or 21 postnatal (P) days were briefly anesthetized for intrathecal injections of saline or clonidine. At each age, the maximum tolerated, antinociceptive (increased hindlimb mechanical withdrawal threshold) and antihyperalgesic (hindpaw carrageenan inflammation) doses were determined. Lumbar spinal cord sections were assessed for apoptosis and cell death (histology, activated caspase-3 immunohistochemistry, Fluoro-Jade C staining), histopathology (hematoxylin and eosin staining), and increased glial reactivity (microglial and astrocytic markers). P3 intrathecal ketamine sections served as positive controls. In additional groups, thermal latency and mechanical withdrawal threshold were measured at P35.

RESULTS

Intrathecal clonidine produces age- and dose-dependent analgesia in rat pups. Maximal doses of clonidine did not alter the degree or distribution of apoptosis or increase glial reactivity in the neonatal spinal cord. No spinal histopathology was seen 1 or 7 days after injection at any age. Intrathecal clonidine did not produce persistent changes in reflex sensitivity to mechanical or thermal stimuli at P35.

CONCLUSIONS

Intrathecal clonidine in the postnatal rat did not produce signs of spinal cord toxicity, even at doses much larger than required for analgesia. The therapeutic ratio (maximum tolerated dose/antihyperalgesic dose) was >300 at P3, >30 at P7, and >10 at P21. These data provide additional information to inform the clinical choice of spinal analgesic drug in early life.

Pediatric pain management

Regional anesthesia has become an integral part of adult anesthesia. Although not routinely used in children because of the need for general anesthesia that is necessary to keep the patients from moving and cooperating with the operator, regional anesthesia has been gaining immense popularity in the last decade. Although there is not much objective evidence, large prospective databases and expert opinion have favored administering regional anesthesia in the asleep child safely because major neural damage has not been reported in children. This review discusses a comprehensive approach to acute pain management in infants, children, and adolescents using regional anesthesia.

Caudal blocks

Caudal anesthesia is the single most important pediatric regional anesthetic technique. The technique is relatively easy to learn (1), has a remarkable safety record (2), and can be used for a large variety of procedures. The technique has been reviewed in the English (3) and French (4) literature, as well as in German guidelines (5) and in pediatric anesthesia textbooks (6).

Caudal additives do not improve the analgesia afforded by levobupivacaine after hypospadias repair

Background:

Caudal analgesia is commonly employed to provide excellent intra- and postoperative analgesia for primary hypospadias repair in children. Several additives to local anesthetics are commonly employed to increase the block duration, although these have uncertain benefits.

Objectives:

This study investigated whether, in caudal analgesia with levobupivacaine 0.25%, the addition of S (+)-ketamine, clonidine, or both agents combined, would prolong postoperative analgesia in patients undergoing primary hypospadias repair.

Patients and Methods:

We conducted a retrospective chart analysis for all patients who underwent hypospadias repair with caudal analgesia over a consecutive 3-period at this institution. The study examined four patient groups, classified according to the analgesia used:

Primary outcome measures were as follows: time to the first postoperative request for analgesia, total first 24-hour postoperative analgesia, and time to hospital discharge.

Results:

The 87 patients included had a mean ± SD age of 21.4 ± 13.5 months and weight of 11.9 ± 2.4 kg. The median doses of levobupivacaine, S (+)-ketamine, and clonidine were 0.7 mg/kg (range, 0.4–1.3), 0.5 mg/kg (0.2–1.1), and 1.8 μg/kg (0.8–2.3), respectively. The addition of S(+)-ketamine, clonidine, or both did not increase the time to first oral analgesia request. Neither did it reduce the total first 24-hour postoperative analgesia requirements or alter hospital discharge time. However, the additive drugs in combination did increase postoperative sedation.

Conclusions:

The addition of S (+)-ketamine or clonidine to levobupivacaine 0.25% in caudal analgesia for hypospadias repair appears to be of no benefit. However, use of the additives in combination increased postoperative sedation.

Psoas compartment block for acute postoperative pain management after hip surgery in pediatrics: a comparative study with caudal analgesia

BACKGROUND

Lower-limb peripheral nerve blocks in pediatrics have gained much more popularity in the last few decades. Our purpose of this study was to compare the postoperative analgesic effects between psoas compartment block (PCB) and caudal block in small children undergoing open hip reduction/osteotomies.

METHODS

Forty American Society of Anesthesiologists physical status I-II children aged 1 to 6 years planned to undergo open hip reduction/osteotomies were administered general anesthesia and then randomly assigned to receive 1 of 2 regional anesthetics: caudal block (group C, n=20) or PCB (group P, n=20). Ropivacaine 0.25% with epinephrine (5 μg/mL) was used in both blocks. The primary outcome of the study was the total consumption of morphine in the first 24 postoperative hrs. Secondary outcomes included dose of intraoperative fentanyl, occurrence of intraoperative hypotension or bradycardia, postoperative pain scores, time to first morphine analgesia, and occurrence of postoperative vomiting or urine retention.

RESULTS

The cumulative dose of morphine administered in the ward in the first postoperative 24 hrs and the time to first rescue morphine dose were higher in group C than in group P (P<0.001). There were no differences between the 2 groups regarding intraoperative and postoperative complications except for the incidence of urine retention, which was higher in group C than in group P (P=0.037).

CONCLUSIONS

Use of single-shot PCB is superior to single-shot caudal block regarding length of postoperative analgesia and cumulative dose of morphine in small children undergoing open hip reduction/osteotomies.

Efficacy and safety of clonidine as additive for caudal regional anesthesia: a quantitative systematic review of randomized controlled trials

BACKGROUND

Clonidine is still the most popular additive for caudal regional anesthesia. Aim of the present quantitative systematic review was to assess the efficacy and safety of the combined use of clonidine and local anesthetics in comparison with caudal local anesthetics alone.

METHODS

The systematic search, data extraction, critical appraisal and pooled analysis were performed according to the PRISMA statement. The systematic search included the Central register of controlled trials of the Cochrane Library (to present), MEDLINE (1966 to present), EMBASE (1980 to present) and CINAHL (1981 to present). Relative risk (RR), mean difference (MD) and the corresponding 95% confidence intervals (CI) were calculated using the Revman(®) statistical software for dichotomous and continuous outcomes.

RESULTS

Twenty randomized controlled trials (published between 1994 and 2010) including 993 patients met the inclusion criteria. There was a longer duration of postoperative analgesia in children receiving clonidine in addition to local anesthetic (MD: 3.98 h; 95% CI: 2.84-5.13; P < 0.00001). Furthermore, there was a lower number of patients requiring rescue analgesics in the clonidine group (RR: 0.72; 95% CI: 0.57-0.90; P = 0.003). The incidence of complications (e.g., respiratory depression) remained very low and was not different to caudal local anesthetics alone.

CONCLUSIONS

There is considerable evidence that caudally administered clonidine in addition to local anesthetics provides extended duration of analgesia with a decreased incidence for analgesic rescue requirement and little adverse effects compared to caudal local anesthetics alone.

Efficacy and adverse effects of ketamine as an additive for paediatric caudal anaesthesia: a quantitative systematic review of randomized controlled trials

BACKGROUND

The aim of this quantitative systematic review was to assess the efficacy and adverse effects of ketamine added to caudal local anaesthetics in comparison with local anaesthetics alone in children undergoing urological, lower abdominal, or lower limb surgery.

METHODS

The systematic search, data extraction, critical appraisal, and pooled data analysis were performed according to the PRISMA statement. All randomized controlled trials (RCTs) were included in this meta-analysis and relative risk (RR), mean difference (MD), and the corresponding 95% confidence intervals (CIs) were calculated using the Revman(®) statistical software for dichotomous and continuous outcomes.

RESULTS

Thirteen RCTs (published between 1991 and 2008) including 584 patients met the inclusion criteria. There was a significant longer time to first analgesic requirements in patients receiving ketamine in addition to a local anaesthetic compared with a local anaesthetic alone (MD: 5.60 h; 95% CI: 5.45-5.76; P<0.00001). There was a lower RR for the need of rescue analgesia in children receiving a caudal regional anaesthesia with ketamine in addition to local anaesthetics (RR: 0.71; 95% CI: 0.44-1.15; P=0.16).

CONCLUSIONS

Caudally administered ketamine, in addition to a local anaesthetic, provides prolonged postoperative analgesia with few adverse effects compared with local anaesthetics alone. There is a clear benefit of caudal ketamine, but the uncertainties about neurotoxicity relating to the dose of ketamine, single vs repeated doses and the child's age, still need to be clarified for use in clinical practice.

Efficacy of clonidine as an adjuvant to bupivacaine for caudal analgesia in children undergoing sub-umbilical surgery

Caudal epidural analgesia with bupivacaine is very popular in paediatric anaesthesia for providing intra- and postoperative analgesia. Several adjuvants have been used to prolong the action of bupivacaine. We evaluated the efficacy of clonidine added to bupivacaine in prolonging the analgesia produced by caudal bupivacaine in children undergoing sub-umbilical surgery. One hundred children, age one to three years, undergoing sub-umbilical surgery, were prospectively randomized to one of two groups: caudal analgesia with 1 ml/kg of 0.25% bupivacaine in normal saline (Group A) or caudal analgesia with 1 ml/kg of 0.25% bupivacaine with 1 µg/kg of clonidine in normal saline (Group B). Post-operative pain was assessed for 24 hours using the FLACC scale. The mean duration of analgesia was significantly longer in Group B (593.4 ± 423.3 min) than in Group A (288.7 ± 259.1 min); P < 0.05. The pain score assessed using FLACC scale was compared between the two groups, and children in Group B had lower pain scores, which was statistically significant. The requirement of rescue medicine was lesser in Group B. Clonidine in a dose of 1 µg/kg added to 0.25% bupivacaine for caudal analgesia, during sub-umbilical surgeries, prolongs the duration of analgesia of bupivacaine, without any side effects.

Effect of epidural clonidine on minimum local anesthetic concentration (ED50) of levobupivacaine for caudal block in children

BACKGROUND

Clonidine has the potential to significantly prolong the duration of caudal epidural anesthesia. We investigated the effect of the addition of clonidine to the MLAC of levobupivacaine in a randomized controlled dose-response trial.

METHODS

A group of 120 children aged <6 years of age received caudal anesthesia with levobupivacaine and 1, 2, or 3 μg·kg(-1) of clonidine. The MLAC was determined according to a Dixon-Massey protocol. The primary outcome was effective surgical anesthesia. Secondary outcomes were the duration of postoperative analgesia, postoperative pain scores, clonidine side effects, and time to hospital discharge.

RESULTS

The MLAC of caudal levobupivacaine was 0.106%, 0.077%, and 0.035% with 1, 2, and 3 μg·kg(-1) of clonidine, respectively. There were significant dose-dependent increases in median duration of analgesia. The incidence of delayed discharge, somnolence, and PONV was significantly increased in the 3 μg·kg(-1) of clonidine group.

CONCLUSIONS

Clonidine produces a local anesthetic sparing effect with a dose-dependent decrease in levobupivacaine MLAC for caudal anesthesia. In addition, there is a dose-dependent prolongation of postoperative analgesia following lower abdominal surgery in children. A dose of 2 μg·kg(-1) of clonidine provides the optimum balance between improved analgesia and minimal side effects.