The efficacy and safety of a clonidine/bupivacaine combination in caudal blockade for pediatric hernia repair

A Comparative Clinical Study between Clonidine and Tramadol with Bupivacaine in Caudal Epidural for Postoperative Analgesia in Pediatric Surgery

Context

Adjuvants to bupivacaine for single shot caudal block in children.

Aims

This study entitled was conducted to compare the effects of addition of tramadol to bupivacaine over addition of clonidine to bupivacaine as a single shot caudal block in children.

Settings and Design

Sixty children of ASA grade I and II in the age group of 2-12 years coming for various infra-umbilical surgeries were included.

Materials and Methods

They were divided into two groups of 30 each. Group BC received caudal bupivacaine 0.25% 0.5ml/kg with clonidine 2 mcg/kg Group BT received caudal bupivacaine 0.25% 0.5 ml/kg with tramadol 2 mg/kg. The main parameters studied were hemodynamic changes, duration of post-operative analgesia and incidence of adverse effects.

Statistical Analysis Used

The results of continuous variables are given as mean ± SD and proportion as percentage. The difference between the two groups was assessed by student's - t test and chi-square test.

Results

The mean duration of post-operative analgesia in group BT was statistically significant (P <0.001), reducing the requirement of analgesics in group BT. There was no difference in sedation score, nausea, vomiting, urinary retention.

Conclusions

The present study demonstrated that caudal administration of bupivacaine 0.25% 0.5 ml/kg with tramadol 2 mg/kg resulted in superior analgesia with longer duration of action and reduced requirement of analgesics in first 24 hours postoperatively when compared with 0.25% bupivacaine 0.5 ml/kg with clonidine 2 mcg/kg.

Caudal Levobupivacaine Supplemented with Caudal or Intravenous Clonidine in Children Undergoing Infraumbilical Surgery: A Randomized, Prospective Double-blind Study

BACKGROUND

Caudal analgesia is the most popular regional anesthesia technique in pediatric population for intraoperative and postoperative analgesia. Clonidine, an α₂ agonist, prolongs analgesia without causing significant respiratory depression after systemic or neuraxial administration. However, the most beneficial route of its administration is still controversial. Thus, we compared the effects of caudal and intravenous (i.v) clonidine on postoperative analgesia produced by caudal levobupivacaine in children undergoing infraumbilical surgery.

METHODS

A comparative three group study was carried out in seventy-five pediatric patients who underwent elective surgery for infraumbilical procedures, under general anesthesia with caudal block. Group A (n = 25) received levobupivacaine 0.25% 1 mL/kg caudally and 5 mL of normal saline i.v, Group B (n = 25) received levobupivacaine 0.25% 1 mL/kg with 1 μg/kg clonidine caudally and 5 mL of normal saline i.v, and Group C (n = 25) received levobupivacaine 0.25% 1 mL/kg caudally and 1 μg/kg clonidine in 5 mL normal saline i.v. Postoperative pain was assessed for 24 h using the Children and Infants Postoperative Pain Scale Score. Ramsay sedation scale and modified Bromage scale were assessed at predetermined time intervals for sedation and motor blockade, respectively.

RESULTS

The mean duration of postoperative analgesia was significantly longer in Group B (16.68 ± 4.7 h) than in Group A (4.24 ± 1.42) and Group C (9.44 ± 3.88 h): P < 0.001. The number of patients not requiring rescue analgesia in Group B was 5, which was significantly higher than in Group C (one patient) and Group A (zero patient): P < 0.001. No motor blockade or sedation was observed in any of the groups.

CONCLUSIONS

Clonidine in a dose of 1 μg/kg added to 0.25% levobupivacaine for caudal analgesia significantly prolongs the duration of analgesia, without any side effects.

Efficacy and Safety of Clonidine as an Adjuvant to Bupivacaine for Caudal Analgesia in Paediatric Infra-Umbilical Surgeries

INTRODUCTION

Caudal analgesia, has gained popularity in paediatric intraoperative and postoperative pain management, more so with the use of adjuvants to prolong its duration, each of them having various results. Clonidine, an alpha2-adrenergic agonist is being used for its analgesic effects in various doses with 0.25% Bupivacaine.

AIM

The study was conducted to compare the analgesic efficacy, haemodynamic safety and side effects of 1 μg/kg Clonidine added to 1 ml/kg of 0.125% Bupivacaine solution for caudal analgesia.

MATERIALS AND METHODS

A prospective, randomised, double-blind, controlled study was carried out in 60 children of ASA Physical Status I, aged 1-10 years, scheduled for infraumbilical operations in a tertiary care centre. They were randomly assigned for caudal analgesia, to either group B: 1ml/kg of 0.125% Bupivacaine solution or group BC: 1ml/kg of 0.125% Bupivacaine and preservative free Clonidine 1μ/kg. All were premedicated with midazolam 0.75 mg/kg orally 30 minutes prior to induction of anaesthesia. Heart rate (HR), Mean Arterial blood Pressure (MAP) and oxygen saturation (SpO2) were monitored. General anaesthesia was induced with thiopentone (1.25%) 5mg/kg and inhalation of oxygen, nitrous oxide and sevoflurane. Postoperative pain, sedation and motor block was assessed by the various scores and patients were monitored for adverse effects.

RESULTS

The mean duration of postoperative analgesia was 3 times longer in group BC. Group B received significantly more doses of rescue analgesic than group BC (p-value of 0.004). There was no significant bradycardia, hypotension, sedation or urinary retention in either of the groups. There was no residual motor blockade at 6 hours. Incidence of vomiting was similar in both the groups.

CONCLUSION

Caudal Clonidine in the dose of 1 μg/kg in children is a satisfactory and efficacious adjuvant to caudal Bupivacaine for producing prolonged postoperative analgesia with minimum side effects.

Dexmedetomidine as an adjuvant to bupivacaine in caudal analgesia in children

Context:

Postoperative pain management is becoming an integral part of anesthesia care. Various techniques of pediatric pain relief have been designed among which the most commonly practiced is caudal epidural block. Several adjuvants have been used to prolong the duration of caudal analgesia such as clonidine, neostigmine, ketamine, opioids, and ephedrine. We have designed the study using dexmedetomidine as an adjuvant to assess analgesic efficacy, duration of postoperative analgesia, hemodynamic stability, postoperative sedation, and any adverse effects in children.

Aims:

The aim is to study the effects of dexmedetomidine as an adjuvant to bupivacaine in caudal analgesia in pediatric patients posted for infraumbilical surgeries.

Settings and Design:

This is a randomized, double-blind study in which effect of dexmedetomidine is studied when added to bupivacaine in the caudal epidural block. The observations are made intraoperatively for hemodynamic stability and postoperatively for the duration of analgesia.

Subjects and Methods:

This study was conducted in 100 children of American Society of Anesthesiologists physical status I and II, aged 2–10 years, undergoing elective infraumbilical surgeries. They were divided into two groups as follows: Group A: (0.25%) bupivacaine 1 ml/kg + normal saline (NS) 1 ml. Group B: (0.25%) bupivacaine 1 ml/kg + 1 μg/kg dexmedetomidine in 1 ml NS. As this study was double-blind, patients were randomly assigned to receive either (bupivacaine + saline) or (bupivacaine + dexmedetomidine) in each group. The patients were observed for hemodynamic stability, respiratory depression, and postoperative pain using face, legs, activity, cry, consolability (FLACC) pain scale for 24 h postoperatively.

Statistical Analysis Used:

Unpaired Student's t-test.

Results:

The mean duration of effective analgesia in Group A patients was 4.33 ± 0.98 h versus 9.88 ± 0.90 h in Group B patients. Likewise, the difference in mean FLACC score of both the groups was also statistically significant, 7.21 ± 0.76 and 6.49 ± 1.72 in Group A and Group B, respectively.

Conclusion:

Dexmedetomidine as adjuvant to Bupivacaine increases duration of caudal analgesia and improves hemodynamic stability without an increase in adverse effects in children undergoing infraumbilical surgeries.

Effect of caudal clonidine on emergence agitation and postoperative analgesia after sevoflurane anaesthesia in children: Randomised comparison of two doses

BACKGROUND AND AIMS

Sevoflurane, a popular inhalational anaesthetic for children, has been associated with significant emergence agitation in the recovery phase. This study was intended to compare two doses of caudal clonidine added to ropivacaine 0.2% in order to decide on the optimal dose for prevention of sevoflurane induced emergence agitation (EA) and to get a meaningful prolongation of postoperative analgesia with minimal side effects.

METHODS

Sixty-one children aged 1-7 years (American Society of Anaesthesiologists physical status I-II) received standardized general anaesthesia with inhaled sevoflurane and caudal epidural block with 0.2% ropivacaine 1 ml/kg for sub-umbilical surgeries. They were assigned randomly to two groups: (I) clonidine 1 μg/kg added to caudal ropivacaine; (II) clonidine 2 μg/kg added to caudal ropivacaine. EA and postoperative analgesia were assessed using pain/discomfort scale score and face, legs, activity, cry, consolability (FLACC) score respectively.

RESULTS

EA was observed in 8 children (26.6%) in group I when compared to only 2 children (6.4%) in group II after first 15 min postoperatively. Incidences of EA at 15 min, as well as total incidence of agitation, were both significantly lower in group II when compared to group I with P < 0.05. Duration of analgesia in group I (12 [8-20] h) and group II (16 [8-20] h) was statistically comparable (P > 0.05). There was no difference in the incidence of sedation or complications.

CONCLUSION

Caudal clonidine 2 μg/kg added to 0.2% ropivacaine 1 ml/kg is suggested to be the optimal dose, for prevention of EA and meaningful prolongation of postoperative analgesia with minimal side-effects.

Comparison of caudal analgesia between ropivacaine and ropivacaine with clonidine in children: A randomized controlled trial

Background:

Addition of clonidine to ropivacaine (0.2%) can potentially enhance analgesia without producing prolonged motor blockade. The aim of the present study was to compare the post-operative pain relieving quality of ropivacaine 0.2% and clonidine mixture to that of plain ropivacaine 0.2% following caudal administration in children.

Methods:

In a prospective, double-blinded, randomized controlled trial, 30 ASA 1 pediatric patients undergoing infraumbilical surgery were randomly allocated to receive a caudal injection of either plain ropivacaine 0.2% (1 ml/kg) (group A) or a mixture of ropivacaine 0.2% (1 ml/kg) with clonidine 2 μg/kg (group B). Objective pain score and need for supplemental analgesics were compared during the 1^st 24 hours postoperatively. Residual post-operative sedation and motor blockade were also assessed.

Results:

Significantly prolonged duration of post-operative analgesia was observed in group B (P<0.0001). Heart rate and blood pressure were not different in 2 groups. Neither motor blockade nor post-operative sedation varied significantly between the groups.

Conclusion:

The combination of clonidine (2 μg/kg) and ropivacaine 0.2% was associated with an improved quality of post-operative analgesia compared to plain 0.2% ropivacaine. The improved analgesic quality of the clonidine-ropivacaine mixture was achieved without causing any significant degree of post-operative sedation or prolongation of motor blockade.

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.

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.

Caudal ropivacaine-clonidine: A better post-operative analgesic approach

The aim was to determine qualitative and quantitative aspects of caudal block, haemodynamic effects, and post-operative pain relief of ropivacaine 0.25% versus ropivacaine 0.25% with clonidine for lower abdominal surgeries in paediatric patients. A double-blind study was conducted among 44 paediatric patients in the Department of Anaesthesiology and Intensive Care of our institute. A total of 44 ASA-I paediatric patients between the ages of 1 and 9 years, scheduled for elective hernia surgery, were enrolled in this randomised double-blind study. The caudal block was administered with ropivacaine 0.25% (Group I) and ropivacaine 0.25% and clonidine 2 µg/kg (Group II) after induction with general anaesthesia. Haemodynamic parameters were observed before, during and after the surgical procedure. Post-operative analgesic duration, total dose of rescue analgesia, pain scores and any side effects were looked for and recorded. All the results were tabulated and analysed statistically. The variables in the two groups were compared using the non-parametric tests. For all statistical analyses, the level of significance was P < 0.05. Forty-four patients were enrolled in this study and their data were subjected to statistical analysis: 22 patients in both the groups were comparable with regard to demographic data, haemodynamic parameters and other vitals and were statistically non-significant (P>0.05). The duration of analgesia was significantly prolonged in Group II (P<0.05). The dose requirement for post-operative pain relief was also significantly lesser in Group II. The incidences of side effects were almost comparable and non-significant. A caudal block with 0.25% of isobaric ropivacaine combined with 2 µg/kg of clonidine provides efficient analgesia intra-operatively and prolonged duration of analgesia post-operatively.

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.

Parent-controlled analgesia in children undergoing cleft palate repair

The aims of this study were to find an optimal basal infusion dose of fentanyl for parent-controlled analgesia (PrCA) in children undergoing cleft palate repair and the degree of parents' satisfaction with PrCA. Thirty consecutive children between 6 months and 2 yr of age were enrolled. At the end of surgery, a PrCA device with a basal infusion rate of 2 mL/hr and bolus of 0.5 mL with lockout time of 15 min was applied. Parents were educated in patient-controlled analgesia (PCA) devices, the Wong Baker face pain scoring system, and monitoring of adverse effects of fentanyl. Fentanyl was infused 0.3 microgram/kg/hr at first, and we obtained a predetermined fentanyl regimen by the response of the previous patient to a larger or smaller dose of fentanyl (0.1 microgram/kg/hr as the step size), using an up-and-down method. ED50 and ED95 by probit analysis were 0.63 microgram/kg/hr (95% confidence limits, 0.55-0.73 microgram/kg/hr) and 0.83 microgram/kg/hr (95% confidence limits, 0.73-1.47 microgram/kg/hr), respectively. Eighty seven percent of the parents were satisfied with participating in the PrCA modality. PrCA using fentanyl with a basal infusion rate of 0.63 microgram/kg/hr can be applied effectively for postoperative pain management in children undergoing cleft palate repair with a high level of parents' satisfaction.

Steal-induction after clonidine premedication: a comparison of the oral and nasal route

BACKGROUND

Clonidine premedication in children reliably provides preoperative sedation and anxiolysis, but onset of oral clonidine is known to be slow. Nasal clonidine has been shown to reach peak plasma levels within 10 min in rodents. The aim of the present study was to compare clinical effects and percentage of steal-induction after clonidine premedication by the oral and nasal route.

METHODS

Forty children, aged 1-6 years, scheduled for minor infraumbilical surgery, were randomly assigned to receive either pure clonidine 4 microgxkg(-1) intranasally (group CN, n = 20) or clonidine 4 microgxkg(-1) orally in syrup (group CO, n = 20) prior to mask induction. Drug acceptance, preoperative sedation and anxiolysis, quality of mask acceptance, recovery profile and parents' satisfaction were evaluated.

RESULTS

Drug acceptance was similar between groups, but quality of taste was significantly better in the oral group. There was no significant difference of preoperative anxiolysis and sedation. The onset of sedative effect was after 38.3 min for oral clonidine and 47.5 min for nasal clonidine. A steal-induction could be performed in 60% of children in each group. Emergence from anesthesia and parents' satisfaction were comparable.

CONCLUSIONS

Intranasal clonidine administration has no advantage over the oral route. Clinical effects were similar with both routes; there was a trend towards a faster onset of sedation with oral clonidine. Clonidine premedication causes light sleep, which allows a steal-induction in 60% of patients.

Clonidine addition prolongs the duration of caudal analgesia

BACKGROUND

In this study, using a dose-ranging design, we examined the effects of clonidine with 0.125% bupivacaine on the duration of post-operative analgesia in caudal anaesthesia in children.

METHODS

We conducted a controlled, prospective study of clonidine in caudal anaesthesia in 60 children, aged 1-10 years, undergoing elective inguinal hernia repair. Induction and maintenance of anaesthesia were performed by inhalation of sevoflurane and nitrous oxide. The children were randomized in a double-blind fashion to four groups, and were given a caudal anaesthetic with either 0.125% plain isobaric bupivacaine (1 ml/kg) or bupivacaine plus 1, 1.5 or 2 microg/kg of clonidine. The blood pressure and heart rate were recorded peri-operatively. Analgesia was evaluated by the modified Children's Hospital of Eastern Ontario Pain Scale (mCHEOPS) or a visual analogue scale (VAS). Paracetamol was given when the mCHEOPS score was greater than five or when the VAS score was greater than 30 mm. The monitoring of scores for pain, haemodynamic changes and post-operative nausea and vomiting was performed by nurses blind to the study allocation.

RESULTS

The duration of analgesia was found to be significantly longer in the group given bupivacaine plus 2 microg/kg of clonidine (median, 650 min; range, 300-900 min). Peri-operative hypotension and bradycardia, post-operative respiratory depression and motor block were not recorded in any patient.

CONCLUSIONS

The addition of clonidine to 0.125% bupivacaine prolongs the duration of post-operative analgesia without any respiratory or haemodynamic side-effects.

Clonidine in paediatric anaesthesia: review of the literature and comparison with benzodiazepines for premedication

BACKGROUND

Children undergoing anaesthesia and surgery can experience significant anxiety and distress during the peri-operative period, but whether routine premedication is necessary is currently debated. Benzodiazepines are the most frequently used drugs as premedication in paediatric anaesthesia. In the US, 50% of young children undergoing surgery receive premedication and midazolam is the most frequently used drug in this context (1). Nishina and coworkers (2) concluded in a review article in 1999 that clonidine, administered via an oral, rectal, or caudal route, is a promising adjunct to anaesthetics and analgesics to enhance quality of peri-operative management in infants and children. Later publications also support the use of clonidine for premedication (3-6). The aim of this communication is to review the use of clonidine in paediatric anaesthesia and to propose clonidine as a promising alternative to midazolam. Clonidine is associated with a number of beneficial effects in the context ofanaesthesia both in adults and children. Why clonidine is not routinely use in clinical practice despite the massive publication list is to a large extent due to the lack of marketing efforts from the pharmaceutical industry since multiplegeneric preparations are now readily available on most markets. Midazolam is also associated with a number of beneficial effects, but is far from an ideal premedicant in children, especially with regards to the amnesia, confusion and long term behavioural disturbances. Clonidine has contrary to midazolam no effect on respiration. We believe that clonidine is a good alternative to midazolam as premedication in infants and children.

Clonidine added to bupivacaine in neonatal spinal anesthesia: a prospective comparison in 124 preterm and term infants

BACKGROUND

Spinal anesthesia (SA) remains the 'gold standard' in neonatal anesthesia for inguinal herniorrhaphy but its short duration impedes its usefulness. We previously demonstrated that clonidine prolongs neonatal SA without immediate side effects.

METHODS

We conducted a prospective observational study of 124 infants undergoing herniorrhaphy under SA with bupivacaine and clonidine. Two cohorts, term (n = 57) and former preterm (n = 67) infants, were evaluated and compared with regard to episodes of apnea, desaturation, and bradycardia within 24 h of SA.

RESULTS

In both groups, postoperative desaturation episodes were unchanged after SA, compared with the 12 preoperative hours, despite significantly increased apnea (P < 0.003 and <0.011 respectively). Transient bradycardias occurred in former preterm infants (P < 0.014): they spontaneously resolved in all cases. Mean arterial pressure did not vary during the study. Upper sensory level of SA, sedation on entering the postanesthesia care unit (PACU) and duration of stay in the PACU were similar in both groups.

CONCLUSIONS

The clinical significance of short apneas, recovering spontaneously without desaturation, remains debatable. It is concluded that addition of clonidine to neonatal SA results in acceptable side effects. Side effects must be compared with the potential advantages before future recommendations.

Clonidine administered as adjuvant for bupivacaine in ilioinguinal-iliohypogastric nerve block does not prolong postoperative analgesia

BACKGROUND

Coadministration of clonidine with local anesthetics is associated with improvement of the quality of peripheral nerve block and significant prolongation of postoperative analgesia. Better analgesia has been reported with clonidine in ilioinguinal nerve block compared with caudal use. The object of this study was to determine whether adding of 1 microg.kg(-1) clonidine to bupivacaine 0.25% in ilioinguinal-iliohypogastric nerve block prolongs postoperative analgesia in children.

METHODS

Ninety-eight children ASA I-II aged between 1 and 12 years, scheduled for elective outpatient herniorrhaphy or orchidopexy were randomly allocated to receive an ilioinguinal-iliohypogastric nerve block either with 0.3 ml.kg(-1) bupivacaine 0.25% plus 1 microg.kg(-1) clonidine or only bupivacaine. Postoperative analgesic needs, time to the first analgesic supplementation and sedation score were assessed in hospital for 6 h postoperatively and at home by telephone call.

RESULTS

Demographic data were similar in both groups. There was no statistical difference in the rate of rescue analgesia between the two groups during the first six postoperative hours (20.4% group clonidine vs 30.6% group no clonidine) (P = 0.17). A slight decrease in systolic blood pressure during surgery was reported in the clonidine group. There was no difference in the scores of sedation between the two groups. At home, 10 patients in the clonidine group and nine patients in the nonclonidine group received analgesic medication. There was no difference between the two groups regarding the number of patients receiving analgesic rescue during the first 24 h (log rank = 0.39). Parental satisfaction was high in both groups.

CONCLUSIONS

Our study failed to demonstrate any advantage in addition of 1 microg.kg(-1) clonidine to 0.25% bupivacaine for ilioinguinal-iliohypogastric nerve block compared with bupivacaine 0.25% alone.

Comparison of the effects of clonidine and ketamine added to ropivacaine on stress hormone levels and the duration of caudal analgesia

BACKGROUND

The purpose of this study was to compare the analgesic quality and duration of ropivacaine 0.2% with the addition of clonidine (1 microg.kg(-1)) with that of ropivacaine 0.2% and the addition of ketamine (0.5 mg.kg(-1)) to that of ropivacaine 0.2% and also compare the postoperative cortisol, insulin and glucose concentrations, sampled after induction and 1 h later following caudal administration in children.

METHODS

According to the randomization, patients in the ropivacaine group (R; n = 25) received ropivacaine 0.2%, 0.75 ml.kg(-1); those in the clonidine group (RC; n = 25) received ropivacaine 0.2% 0.75 ml.kg(-1) plus clonidine 1 microg.kg(-1) and those in the ketamine/ropivacaine group (RK; n = 25) ropivacaine 0.2% 0.75 ml.kg(-1) plus ketamine 0.5 mg.kg(-1) (10 mg.ml(-1) concentration). Drugs were diluted in 0.9% saline (0.75 ml.kg(-1)) and prepared by a staff anesthesiologist not otherwise involved in the study. In all groups, the duration of analgesia, analgesic requirements, sedation and insulin, glucose, cortisol concentrations were recorded and statistically compared.

RESULTS

There were no significant differences among the three study groups with respect to age, weight or duration of surgery. Caudal administration of clonidine 1 microg.kg(-1) or ketamine 0.5 mg.kg(-1) induced a longer duration of analgesia (P < 0.05) compared with ropivacaine alone. Insulin levels were increased and cortisol reduced in all groups. Glucose concentration was increased in all groups and statistically significant (P < 0.05).

CONCLUSIONS

Addition of ketamine and clonidine to ropivacaine 0.2% 0.75 ml.kg(-1), when administered caudally in children, prolongs the duration of postoperative analgesia. The need for subsequent postoperative analgesic is also reduced. Caudal analgesia attenuates or allows partial changes to postoperative cortisol, insulin or blood glucose responses to surgery.

The addition of clonidine 2 microg.kg-1 does not enhance the postoperative analgesia of a caudal block using 0.125% bupivacaine and epinephrine 1:200,000 in children: a prospective, double-blind, randomized study

BACKGROUND

In this prospective, randomized, double-blind study, we compared the efficacy of 0.125% bupivacaine and epinephrine 1:200,000 with and without clonidine 2 microg.kg-1 for 'single shot' pediatric caudal analgesia.

METHODS

Thirty ASA I and II children, ages 2-8 years, undergoing outpatient surgical procedures below the umbilicus received 1 ml.kg-1 0.125% bupivacaine with fresh epinephrine 1:200,000 and clonidine 2 microg.kg-1 (group-C) or 1 ml.kg-1 0.125 % bupivacaine with epinephrine 1:200 000 (group-NC). All patients received a standardized general anesthetic (induction with 67% N2O in O2 and sevoflurane followed by isoflurane maintenance). Primary outcome measures were time to first rescue analgesic and number of patients requiring rescue analgesic at 4, 6, 8, 12, and 24 h after caudal placement. Secondary outcome measures included: extubation times, Objective Pain Scale (OPS) scores, sedation scores, time in postanesthesia care unit (PACU), discharge time, number of analgesic doses given in 24 h following caudal blockade, and adverse effects (vomiting, hypotension, and bradycardia).

RESULTS

There were no differences in demographics, investigated parameters, or adverse effects between groups.

CONCLUSIONS

We found that the addition of clonidine 2 microg.kg-1 to 0.125% bupivacaine with fresh epinephrine 1:200,000 for caudal analgesia did not significantly delay the time to first rescue analgesic or decrease the overall need for rescue analgesics in children 2-8 years undergoing surgical procedures below the umbilicus.

Clonidine vs. midazolam as premedication in children undergoing adeno-tonsillectomy: a prospective, randomized, controlled clinical trial

BACKGROUND

Clonidine administration in the setting of paediatric anaesthesia is associated with a number of desirable effects, e.g. preoperative sedation, analgesia and reduced anaesthetic requirements. The aim of the current study was to compare postoperative outcome variables using a prospective, randomized, double-blind design after premedication with clonidine or midazolam.

METHODS

One hundred paediatric ASA physical status 1 patients (age 1-11 year) scheduled for adeno-tonsillectomy were assigned to receive rectal premedication with midazolam (300 microg kg(-1) and atropine 40 microg kg(-1); group M, n = 52) or clonidine (5 microg kg(-1 and) atropine 40 microg kg(-1); group C, n = 48) prior to a standardized sevoflurane anaesthetic. The incidence of immediate postoperative pain (0-2 h), as assessed by repeated Objective Pain Scale (OPS) scores, was chosen as the primary end-point of the study. Degree of sedation (modified Vancouver sedation scale 0-3), occurrence of postoperative vomiting (POV), and incidence of shivering and immediate postoperative confusion were registered as secondary end-points. After hospital discharge parents were instructed to continue the evaluation of pain, sedation, POV and sleep pattern during a 24-h period. Parents were also asked for their preference concerning the postoperative behaviour of their child (calm, sedated vs. alert, active).

RESULTS

In the early postoperative period patients in the clonidine group had a significantly lower sum of 5 OPS scores (median = 8.0) compared to group M (median = 11.5) (P = 0.011). Administration of clonidine was also associated with a slightly higher sum of sedation scores (median = 13) in the early postoperative period compared to children receiving midazolam (median = 12) (P < 0.001). No episode of shivering was observed in the clonidine group but was present in five of the patients in the midazolam group (P = 0.057). In younger children (< 5 years) the incidence of postoperative confusion was lower in the clonidine group (P = 0.001). No difference in the frequencies of POV incidences, degree of postoperative pain, need for analgesics, or sleep pattern during the first 24 postoperative hours could be observed between the groups according to the parental evaluation. Children premedicated with clonidine were more calm and sedated compared to children in the midazolam group (P = 0.024) as judged by their parents. A significant majority of parents (75%; P < 0.001) preferred a calm and sedated child during the first postoperative 24-h period.

CONCLUSION

Rectal premedication with clonidine was associated with a significant reduction of pain in the early postoperative period compared to midazolam and was also associated with moderately increased sedation during the first 24 postoperative hours. The sedative effect of clonidine is in agreement with the unambiguous finding of a parental preference for a calm and sedated child during the first 24 postoperative hours.

Caudal analgesia in children: S(+)-ketamine vs S(+)-ketamine plus clonidine

BACKGROUND

The aim of this study was to evaluate postoperative analgesia provided by caudal S(+)-ketamine and S(+)-ketamine plus clonidine without local anesthetic.

METHODS

Forty-four children aged 1-5 years consecutively scheduled for inguinal hernia repair, hydrocele repair or orchidopexy were randomly assigned to receive a caudal injection of either S(+)-ketamine 1 mg x kg(-1) (group K) or S(+)-ketamine 0.5 mg x kg(-1) plus clonidine 1 microg x kg(-1) (group KC). Postoperative analgesia and sedation were evaluated by CHEOPS and Ramsay scale from emergence from general anesthesia for 24 h.

RESULTS

No statistical difference was observed between study groups with respect to pain and sedation assessment. A slight trend toward a reduced requirement for rescue analgesia in group KC was observed, although not statistically significant.

CONCLUSIONS

Caudal S(+)-ketamine 1 mg x kg(-1) and S(+)-ketamine 0.5 mg x kg(-1) plus clonidine 1 microg x kg(-1) are safe and provide effective postoperative analgesia in children without adverse effects.

Analgesic effect of clonidine added to bupivacaine 0.125% in paediatric caudal blockade

BACKGROUND

Caudals are a common method of providing pain relief in children undergoing surgery. Clonidine, an alpha(2) agonist, exhibits significant analgesic properties. The current investigation sought to determine whether caudal clonidine added to caudal bupivacaine would decrease pain in paediatric patients undergoing surgery.

METHODS

Thirty-six children undergoing elective surgery were studied. Following anaesthetic induction, a caudal was placed (1 mg.kg(-1) bupivacaine 0.125%) with an equal volume of either clonidine (2 microg.kg(-1)) or saline. Perioperative analgesic requirements in the postanaesthesia care unit (PACU) and at home following hospital discharge, and parental pain scores were evaluated.

RESULTS

There were no significant demographic, haemodynamic, or pain score differences between the groups. There was no difference in analgesic duration between groups. There were significantly more children who vomited during the first 24 postoperative hours in the clonidine group than in the saline group (eight in clonidine, two in saline; P < 0.05).

CONCLUSION

We do not recommend adding clonidine (2 microg.kg(-1)) to a bupivacaine (0.125%) caudal block in children undergoing surgery.

Nonopioid additives to local anaesthetics for caudal blockade in children: a systematic review

BACKGROUND

Caudal epidural injection with local anaesthetics is a popular regional technique used in infants and children. A disadvantage of caudal blockade is the relatively short duration of postoperative analgesia. Opioids have traditionally been added to increase the duration of analgesia but have been associated with unacceptable side-effects. A number of nonopioid additives have been suggested to increase the duration of analgesia.

METHODS

A systematic review was conducted to identify randomized control trials comparing the use of local anaesthetic to local anaesthetic with nonopioid additives for caudal blockade in children. The increase in duration of analgesia and side-effects were compared.

RESULTS

The addition of clonidine to the local anaesthetic solution produces an increase in the duration of analgesia following caudal blockade in children (pooled weighted mean difference of 145 min with 95% confidence interval of 132-157 min). Side-effects include sedation and the potential for neonatal respiratory depression. Ketamine and midazolam further increase the duration of analgesia, however, the potential for neurotoxicity remains a concern.

CONCLUSION

The evidence examined shows an increased duration of analgesia with clonidine, ketamine and midazolam. However, we are not convinced that the routine use of these adjuvants in the setting of elective outpatient surgery shows improved patient outcome. It is unclear if the potential for neurotoxicity is outweighed by clinical benefits. Further testing, including large clinical trials, is required before recommending routine use of nonopioid additives for caudal blockade in children.

Spinal versus peripheral effects of adjunct clonidine: comparison of the analgesic effect of a ropivacaine-clonidine mixture when administered as a caudal or ilioinguinal-iliohypogastric nerve blockade for inguinal surgery in children

BACKGROUND

The adjunctive use of clonidine to local anaesthetics has been reported to enhance analgesia both after spinal and peripheral administration. However, no attempt has been made to compare spinal and peripheral application of clonidine in the same surgical context in order to further explore the mechanism for the analgesic action of clonidine when administered together with local anaesthetics.

METHODS

Using a prospective, randomized, observer-blinded study design, 40 patients, aged 1-7 years, who were undergoing elective surgery for inguinal hernia repair or orchidopexy, were randomly allocated to receive either a caudal block (group C: n = 20; ropivacaine 0.2%, 1 ml.kg-1 + clonidine 2 micro g.kg-1) or an ilioinguinal-iliohypogastric nerve block (group I: n = 20; ropivacaine 0.2%, 0.4 ml.kg-1 + clonidine 2 micro g.kg-1) following the induction of a standardized sevoflurane based anaesthetic. Postoperative analgesia [maximum Objective Pain Scale (OPS) score and requirement for supplemental analgesia] and sedation (three-point scale) were assessed at predetermined intervals during the first 24 h postoperatively.

RESULTS

Fourteen children in group I and nine children in group C did not require rescue analgesia (P = 0.17). No difference in maximum OPS scores could be detected between the two study groups. The mean time to full recovery regarding sedation was 149 min and 153 min in groups C and I, respectively.

CONCLUSIONS

This pilot study demonstrates a trend for better postoperative analgesia following peripheral administration of clonidine compared with central application. However, the main mechanism for the adjunct analgesic effect of clonidine when administered together with local anaesthetics requires further study.

Apnoea in a former preterm infant after caudal bupivacaine with clonidine for inguinal herniorrhaphy

Awake regional anaesthesia for inguinal hernia repair in former preterm infants is suggested to avoid life-threatening respiratory complications known to occur after general anaesthesia. Caudal anaesthesia is becoming a more popular technique for this purpose. To prolong duration of anaesthesia and to reduce postoperative need for analgesics in these infants, caudal clonidine has been considered useful. We report a former preterm infant, who had two awake caudal anaesthetics for herniotomy within 3 weeks. The first was uneventful with bupivacaine 0.25% at 35 weeks postconceptional age. At 38 weeks, the baby suffered form intra- and postoperative apnoeas after inadvertent administration of bupivacaine 0.125% plus clonidine.

Analgesia for circumcision in a paediatric population: comparison of caudal bupivacaine alone with bupivacaine plus two doses of clonidine

BACKGROUND

Clonidine is often used to improve the duration and quality of analgesia produced by caudal epidural blockade, although the optimum dose of clonidine with bupivacaine remains uncertain.

METHODS

We compared the effect of clonidine, 1 and 2 microg x kg(-1), added to bupivacaine (1.25 mg x kg(-1)) with that of bupivacaine alone in 75 male children undergoing elective circumcision.

RESULTS

There was a trend towards increasing duration of analgesia with increasing dose of clonidine [group B (bupivacaine) 280.7 (171.6) min, C1 (bupivacaine + clonidine 1 microg x kg(-1)) 327.8 (188.3) min and C2 (bupivacaine + clonidine 2 microg x kg(-1)) 382.0 (200.6) min], although this difference was not statistically significant. Mean time to arousal from anaesthesia was significantly prolonged with clonidine 2 microg kg(-1) (group C2 21.3 (13-36) min, group C1 14.0 (6-25) min and group B 14.4 (2-32) min. Supplementary analgesic requirements and incidence of adverse effects were low, with no differences between the groups.

CONCLUSIONS

For paediatric circumcision, under general anaesthesia, the addition of clonidine 2 microg x kg(-1) to low volume (0.5 ml x kg(-1)) caudal anaesthetics has a limited clinical benefit for children undergoing circumcision.

Management of the paediatric patient

Recent introduction of new fast-onset short-duration anaesthetic drugs and the use of regional anaesthesia techniques in children have resulted in good control of anaesthesia and perioperative pain with few adverse effects. Ambulatory surgery has gained popularity in paediatric practice, particularly as children are often otherwise healthy and usually undergo minor surgery.