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.     

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.     

How to prolong postoperative analgesia after caudal anaesthesia with ropivacaine in children: S-ketamine versus clonidine

BACKGROUND: The aim of the study was to determine whether caudal S-ketamine or clonidine prolonged analgesia together with ropivacaine. METHODS: Sixty-three boys, aged 1-5 years, who were undergoing minor surgery, were allocated in order to receive one of three solutions for caudal anaesthesia. Group R received 2 mg x kg(-1) 0.2% ropivacaine; group C, 2 mg x kg(-1) 0.2% ropivacaine + clonidine 2 microg x kg(-1); and group K, 2 mg x kg(-1) 0.2% ropivacaine + S-ketamine 0.5 mg x kg(-1). RESULTS: Postoperative analgesia assessed by CHEOPS lasted 701 min in group K (P < 0.05) compared with 492 min in group C and 291 min in group R. There were no significant differences between the groups for incidence of haemodynamic and respiratory alterations, motor block or sedation. CONCLUSIONS: This study demonstrates that S-ketamine 0.5 mg x kg(-1) when added to 0.2% caudal ropivacaine provides better postoperative analgesia than clonidine without any clinically significant side-effect.     

Ropivacaine 0.25% compared with bupivacaine 0.25% by the caudal route.

We compared in a randomized double-blind study, the postoperative analgesia and degree of motor block produced by the new local anaesthetic ropivacaine, with bupivacaine, for caudal anaesthesia in children. Eighty children, 2-5-years-old, ASA I, received one of two local anaesthetics; either ropivacaine 0.25% (1.0 ml x kg(-1)) or bupivacaine 0.25% (1.0 ml x kg(-1)). They were sedated with a continuous infusion of propofol (200 microg x kg(-1) min(-1). The lungs were ventilated with a mixture of 50% nitrous oxide with oxygen. 60 min after local anaesthetic injection, and every 60 min, the extent of the motor block in the recovery room was scored as 1-3, according to a modified Bromage scale. Adverse events and the time to the first analgesic requirement were reported. Patients in the two groups did not differ with respect to age, weight and height. There were no differences in heart rate and arterial pressure between the two groups(P>0.05). No adverse events were observed. The ropivacaine group showed a shorter duration of motor block than the bupivacaine group (P<0.05). The first postoperative analgesic requirement was a mean (sd) of 5 h+/-4.32 after the operation in the ropivacaine group and 5 h+/-3.81 for the bupivacaine group. These findings suggest that caudal anaesthesia with ropivacaine 0.25% in paediatric patients can be effective, with less motor blockade in the postoperative period.     

Comparison of clonidine 1 microgram kg-1 with morphine 30 micrograms kg-1 for post-operative caudal analgesia in children

In a prospective randomized study in children, we compared caudal bupivacaine-clonidine with bupivacaine-morphine to evaluate whether clonidine can be used as an alternative to morphine in caudal anaesthesia. Caudal anaesthesia was administered in 36 children undergoing orchidopexy, hernia repair or circumcision, using 1.5 mL kg-1 bupivacaine 0.18% with either 1 microgram kg-1 clonidine (group 1) or 30 micrograms kg-1 morphine (group 2). Haemodynamic and respiratory parameters, anaesthetic requirements, recovery time and pain score were monitored for 24 h. Eleven children in group 1 and nine children in group 2 did not need any supplementary systemic analgesics throughout the 24-h observation period. Mean (+/- SD) duration of analgesia in the remaining patients was 6.3 h (+/- 3.3 h) in group 1 and 7.1 h (+/- 3.4 h) in group 2 (P = 0.43). Recovery time after anaesthesia was significantly longer in group 1 (16.6 +/- 8.8 min) than in group 2 (11.5 +/- 4.7 min) (P < 0.05). We conclude that analgesia provided by 1 microgram kg-1 clonidine added to caudal bupivacaine is comparable with that provided by 30 micrograms kg-1 caudal morphine with bupivacaine. Clonidine at this low dose did not cause respiratory depression.     

Caudal neostigmine for postoperative analgesia in paediatric surgery

BACKGROUND: This study was conducted to evaluate analgesia and side-effects of caudal neostigmine coadministered with bupivacaine in paediatric surgery. METHODS: We studied children, aged 1-5 years, undergoing elective surgery (inguinal hernia and hypospadias). After standard induction of anaesthesia, caudal anaesthesia was performed. Group 1 received 0.25% bupivacaine 0.5 ml.kg-1 and Group 2 received 0.25% bupivacaine 0.5 ml x kg-1 with 1 microg x kg-1 neostigmine via the caudal route. Heart rate, mean arterial pressure, peripheral oxygen saturation were recorded before induction, after induction but before caudal anaesthesia, and then every 5 min after caudal anaesthesia. Haemodynamic, Toddler, Preschooler, Postoperative Pain Scale (TPPPS) pain score and sedation score values were recorded 30 min after extubation and at hours 2, 4, 6, 12 and 24. A pain score >3/10 resulted in administration of rectal paracetamol. The duration of postoperative analgesia was defined as the time between caudal drug injection and the first rectal paracetamol administration. RESULTS: There were no differences between the groups in demographic and haemodynamic date, duration of surgery and anaesthesia, time to extubation or sedation scores. The duration of postoperative pain relief did not differ between the two groups; 15.40 +/- 10.97 h for group 1 vs. 15.45 +/- 10.99 h for group 2 (P > 0.05). The incidence of nausea (three patients in group 2 and one patient in group 1) was not statistically significant. No other side-effects were seen. CONCLUSIONS: We found that a single caudal injection of 1 microg x kg-1 neostigmine mixed with bupivacaine offers no significant advantage over bupivacaine alone for postoperative pain relief in children undergoing genitourinary surgery.     

Comparison of fentanyl-bupivacaine or midazolam-bupivacaine mixtures with plain bupivacaine for caudal anaesthesia in children

BACKGROUND: The aim of this study was to evaluate the intensity and effectiveness of 0.75 ml.kg-1 bupivacaine 0.25% with the addition of fentanyl or midazolam for caudal block in children undergoing inguinal herniorrhaphy. METHODS: Seventy-five children were allocated randomly to three groups to receive a caudal block with either 0.25% bupivacaine with fentanyl 1 microg.kg(-1) (group BF) or with midazolam 50 microg.kg(-1) (group BM) or bupivacaine alone (group B) after induction of anaesthesia. Haemodynamic parameters, degree of pain, additional analgesic requirements and side-effects were evaluated. RESULTS: The mean systolic arterial pressure at 10, 20, 30 min after caudal block was higher in group B compared with groups BF and BM. Mean intraoperative heart rate was lower in group BF than the other groups. Adequate analgesia was obtained in all patients (100%) in group BF, 23 patients (92%) in group BM and 21 patients (84%) in group B (P > 0.05). The time to recovery to an Aldrete score of 10 was significantly shorter in group B than group BM (P < 0.05). Although not significant, it was also shorter in group B than group BF. There was no difference in additional analgesic requirements between the groups in the first 24 h. Sedation score was higher in the midazolam group at 60 and 90 min postoperatively than the other groups. CONCLUSIONS: Caudal block with 0.75 ml.kg(-1) 0.25% bupivacaine and 50 microg.kg(-1) midazolam or 1 microg.kg(-1) fentanyl provides no further analgesic advantages to bupivacaine alone when administered immediately after induction of anaesthesia in children undergoing unilateral inguinal herniorrhaphy.     

A comparison between local anaesthetic dorsal nerve block and caudal bupivacaine with ketamine for paediatric circumcision

BACKGROUND: Ketamine has been shown to prolong analgesia produced by caudal local anaesthetic block and is now in common use. This study compares caudal block using bupivacaine/ketamine with dorsal nerve block of the penis. METHODS: Sixty boys undergoing elective circumcision were given either 0.5 ml x kg-1 of bupivacaine 0.15% with ketamine 0.5 mg x kg-1 (n = 30) or dorsal nerve block of the penis with bupivacaine 0.5% (n = 30) as a supplement to general anaesthesia. Postoperative pain was assessed by parents using a modified objective pain score, and the time taken to first requirement of analgesia was recorded. Motor weakness, time to first micturition, postoperative nausea and vomiting (PONV), eating habits, sleep disturbance and behaviour were also assessed. RESULTS: There was no difference between the groups in time to first requirement for analgesia or number of doses of paracetamol given in the first 24 h. Almost half the boys in the caudal group had motor weakness, and there was a significant increase in time to first micturition in that group. There was no difference between the groups in PONV, eating, sleeping or behavioural disturbance. CONCLUSIONS: Caudal anaesthesia with bupivacaine/ketamine does not confer any advantage over a dorsal nerve block with the doses used in this study. Because of the higher incidence of side-effects and technique failure in the caudal group, dorsal nerve block is perhaps the preferred technique.     

Total knee replacement: a comparison of ropivacaine and bupivacaine in combined femoral and sciatic block

BACKGROUND: Femoral and sciatic nerve block may improve post-operative analgesia following total knee replacement. OBJECTIVES: To compare the post-operative analgesia following primary total knee replacement provided by spinal anaesthesia alone or in combination with femoral and sciatic nerve block with bupivacaine or ropivacaine. METHODS: Seventy-five patients were randomised into one of three groups: spinal anaesthesia only; spinal anaesthesia and combined femoral and sciatic nerve block with 1 mg x kg(-1) bupivacaine 7.5 mg x ml(-1) to each nerve; spinal anaesthesia and combined femoral and sciatic nerve block with 1 mg x kg(-1) ropivacaine 7.5 mg x ml(-1) to each nerve. RESULTS: The mean (SD) time to first morphine request was significantly prolonged for both groups receiving combined femoral and sciatic block, 912 (489) min for the bupivacaine group and 781 (394) min for the ropivacaine group (P<0.001) compared with 413 (208) min for the group receiving spinal anaesthesia alone. Morphine consumption was significantly reduced in both groups receiving combined femoral and sciatic block. There were no systemic or neurological sequelae in any of the groups. CONCLUSIONS: Femoral and sciatic blockade following intrathecal bupivacaine/diamorphine provided superior analgesia when compared with intrathecal bupivacaine/diamorphine alone. There were no significant clinical differences between the group receiving bupivacaine 7.5 mg x ml(-1) and the group receiving ropivacaine 7.5 mg x ml(-1).     

Caudal clonidine and bupivacaine for combined epidural and general anaesthesia in children

Background: Clonidine produces analgesia by actions on α₂-ad-renoceptors and enhances both sensory and motor blockade from epidural injection of local anaesthetics. Low-dose clonidine has been used so far for caudal injection in children. Our aim was to study the perioperative effects of high-dose caudal clonidine when added to low concentration of bupivacaine for combined epidural and general anaesthesia in children. Methods: After induction of general anaesthesia caudal block was performed either with 1 ml kg^-1 bupivacaine 0.175% with the addition of clonidine 5 μg kg^-1 (n=20), or with 1 ml kg^-1bupivacaine 0.175% (n=20). The intraoperative anaesthetic requirements, the perioperative haemodynamic effects, respiratory rate, sedation score, postoperative pain scores and side effects were assessed by a blinded observer. A patient-controlled analgesia system was used for postoperative pain relief. The quality of postoperative pain relief was assessed using Smiley's pain analogue scale. Results: Intraoperative haemodynamic responses did not differ between the groups. However, during emergence from general anaesthesia children in the clonidine group had significantly lower heart rates and blood pressures compared to children in the control group. In addition, heart rates and blood pressures were also lower in the clonidine group in the early postoperative period (P?< 0.05). Postoperative analgesia was significantly better in the clonidine group as evidenced by the total number of requests (3 vs 12, P< 0.05) and the total amount of tramadol (20.5 mg vs 72.8 mg, P < 0.05) administered. The duration of the caudal analgesia was significantly longer in the clonidine group (20.9±7.4 h vs 14.4±10.9 h, P< 0.05). Conclusion: Our results suggest that caudal clonidine 5 μg kg^-1 enhances and prolongs caudal blockade with bupivacaine 0.175% in children. It also blocks sympathoadrenergic responses during emergence from anaesthesia. Sedation and cardiovascular effects are observed up to 3 h into the postoperative period.     

Comparison of ropivacaine with bupivacaine for paediatric caudal block

In a double-blind, multicentre study 245 children aged 1-10 yr undergoing elective minor surgery as inpatients were randomly allocated to receive a single caudal extradural injection of 1 ml kg-1 of either 0.25% bupivacaine or 0.2% ropivacaine after induction of light general anaesthesia. The groups were comparable for age, weight, vital signs and duration of surgery. The onset time was similar for ropivacaine and bupivacaine (9.7 vs 10.4 min). Further analgesia was not required in 40% of children. The mean time to first analgesia in the remainder was 233 min in the bupivacaine group and 271 min in the ropivacaine group. No motor block was measurable in either group. Ropivacaine 2 mg kg-1 was as effective as bupivacaine 2.5 mg kg-1 for caudal analgesia in children.      

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.     

A randomized trial of caudal block with bupivacaine 4 mg x kg-1 (1.8 ml x kg-1) plus morphine (150 microg x kg-1) vs general anaesthesia with fentanyl for cardiac surgery

BACKGROUND: Regional anaesthesia has been used effectively in paediatric patients undergoing cardiac surgery and is thought to be safe. METHODS: Thirty patients ASA physical status II-III undergoing scheduled palliative or corrective cardiac surgery, receiving premedication with midazolam and anaesthetic induction with sevoflurane, fentanyl and pancuronium were randomly allocated to two groups. In group 1, patients received bupivacaine 0.22% 4 mg.kg-1 (1.8 ml.kg-1) and morphine 150 microg x kg-1 by the caudal route. After a 20-min period for the block to take effect, sevoflurane 0.5-1.0% and fentanyl 5 microg x kg-1 were administered for maintenance of anaesthesia. In group 2, the anaesthetic technique was the same as in group 1, without a caudal block and fentanyl 25 microg x kg-1 was administered at the moment of surgical incision. RESULTS: Cardiovascular and haemodynamic responses of patients receiving caudal block showed minor variations during the 20-min period between caudal and general anaesthesia. Fentanyl requirements during surgery were lower (P = 0.001) in patients with caudal block than patients with general anaesthesia. Extubation time was shorter (P = 0.034) in the caudal group. Two patients in the general anaesthesia group and one in the caudal group died because of postoperative complications. CONCLUSIONS: Caudal block with bupivacaine 0.22% 4 mg.kg-1 (1.8 ml.kg-1) and morphine 150 microg x kg-1 was safe and effective for paediatric patients undergoing cardiac surgery. However, patients might have a better outcome with a reduction of morphine dosage and administration of a muscle relaxant of shorter duration of action than pancuronium.     

Effects of intrathecal clonidine on duration of bupivacaine spinal anaesthesia, haemodynamics, and postoperative analgesia in patients undergoing knee arthroscopy

Clonidine, an alpha–2–adrenergic agonist, may have a clinically relevant analgesic action but also a hypotensive action, when administered spinally. In this study, therefore, the analgesic and circulatory effects of intrathecal clonidine were studied in patients undergoing knee arthroscopy under spinal anaesthesia. Forty ASA I–II patients were randomly divided to two groups. One group received clonidine 3 μg–kg^-1 mixed with 15 mg 0.5% bupivacaine and the other group an identical saline volume mixed with bupivacaine as above, in a double–blind fashion. Sensory analgesia, blood pressure, heart rate and sedation were followed during and after the operation. Oxycodone 0.14 mg– kg"' i.m. or ketoprofen 100 mg p.o. was administered when needed. The duration of sensory analgesia (until regression of the block to L2) was longer in the clonidine group (mean 217 min) than in the control group (mean 160 min) ( P < 0.05). Duration of motor blockade was also longer in the clonidine group (mean 215 min) compared to the control group (161 min) ( P < 0.05). Mean arterial pressure and heart rate were significantly lower in the clonidine group compared to the control group. The clonidine patients needed fewer supplemental doses of oxycodone (8 doses) than those in the control group (16 doses) ( P < 0.05). More patients in the clonidine group were sedated 3–6 h after the injection ( P < 0.05). Addition of clonidine prolonged the bupivacaine spinal block. However, marked haemodynamic changes and sedation may limit the usefulness of intrathecal clonidine.     

Remifentanil vs alfentanil in the total intravenous anaesthesia for paediatric abdominal surgery

BACKGROUNDS: Our aim was to investigate whether total intravenous anaesthesia (TIVA) with remifentanil and alfentanil would ensure appropriate analgesia and recovery conditions in anaesthesia for children undergoing abdominal surgery. METHODS: Sixty children, scheduled for abdominal operations were randomized to receive, in a double-blind manner, either remifentanil (loading dose 1 microg x kg(-1); maintenance infusion, 0.25 microg x kg(-1) min(-1)) or alfentanil (loading dose 50 microg x kg(-1); maintenance infusion, 1 microg x kg(-1) min(-1)) as the analgesic component of TIVA. They were combined with propofol (loading dose, 2 mg x kg(-1); step 1 maintenance infusion, 10 mg x kg(-1) h(-1); step 2 maintenance infusion, 8 mg x kg(-1) h(-1); step 3 maintenance infusion, 6 mg x kg(-1) h(-1)) neuromuscular blockade was with mivacurium. Dose changes of the drugs, the times from cessation of anaesthesia to extubation, verbal responses, recovery of ventilation, orientation, and qualification for discharge from the postanaesthetic care unit (PACU) were recorded. RESULTS: Demographics, duration of surgery and anaesthesia were similar between the two groups. Times to extubation and stay in the PACU were significantly shorter in the remifentanil group compared with the alfentanil group. Quality of emergence (QE) from anaesthesia scale scores were higher in the remifentanil group compared with the alfentanil group. CONCLUSIONS: Remifentanil provides a more rapid recovery and adequate postoperative analgesia after TIVA for paediatric abdominal surgery, compared with alfentanil.     

Addition of clonidine or fentanyl to local anaesthetics prolongs the duration of surgical analgesia after single shot caudal block in children

Caudal anaesthesia is indicated for surgical procedures lasting less than 90 min. Fentanyl and clonidine are known to prolong postoperative caudal analgesia, but there are no data on their effect on duration of surgical analgesia. We evaluated if the addition of clonidine or fentanyl to local anaesthetics prolonged the duration of surgical analgesia after single shot caudal block in children in a randomized, double-blind study. We studied 64 children, aged 6-108 months, undergoing bilateral correction of vesicoureteral reflux which was expected to last more than 90 min. Patients were allocated to one of four groups: group O received 1 ml kg-1 of a mixture of 0.25% bupivacaine with epinephrine and 1% lidocaine in equal parts; group F received the same mixture of local anaesthetics in addition to fentanyl 1 microgram kg-1; group C received the same mixture of local anaesthetics in addition to clonidine 1.5 micrograms kg-1; and group C + F received the same mixture of local anaesthetics in addition to fentanyl 0.5 microgram kg-1 and clonidine 0.75 microgram kg-1. Single shot caudal block was sufficient in only 57% of children in group O compared with 93% in groups C and F and 86% in group C + F (P = 0.035). Global assessment of anaesthesia, defined as the time from caudal injection to the first administration of analgesic (either during or after surgery), was significantly longer in the three groups of children who received additives compared with local anaesthetics alone (P = 0.035), but there were no differences between the three additive groups. Vomiting was observed only in children who received fentanyl. Addition of clonidine or fentanyl to local anaesthetics prolonged the duration of surgical analgesia of caudal block, allowing single shot caudal anaesthesia to be recommended for surgery lasting 90-150 minutes. Clonidine had some advantages over fentanyl as it did not produce clinically significant side effects.      

Comparison of caudal epidural bupivacaine with bupivacaine plus tramadol and bupivacaine plus ketamine for postoperative analgesia in children

This study compared the effect of single-dose caudal epidural bupivacaine, bupivacaine plus ketamine and bupivacaine plus tramadol for postoperative pain management in children having surgery for inguinal hernia. Following ethics committee approval and informed parental consent, 75 children ASA PS I and II, between three and nine years of age and scheduled for elective unilateral inguinal hernia repair with general anaesthesia were recruited. The patients were randomly divided into three groups to receive 0.5 ml/kg caudal bupivacaine 0.25% (group B), bupivacaine 0.25% plus tramadol 1 mg/kg (group BT) or bupivacaine 0.25% plus ketamine 0.5 mg/kg (group BK). The injections were performed under general anaesthesia. Mean arterial pressure, heart rate, pulse oximetry, respiratory rate and sedation and pain scores were recorded at defined intervals following recovery from anaesthesia. The groups were similar in age, weight and duration of operation (P >0.05). No patient experienced hypotension, bradycardia or respiratory depression. Duration of analgesia was (mean+/-SD) 6.5+/-4.1 h in group B, 9.2+/-3.9 h in group BK, and 8.5+/-3.1 h in group BT (P <0.05). More patients in group B required supplementary analgesics in the first 24 h (P <0.05). Sedation scores were comparable in all groups. Incidence of emesis and pruritus was similar in all the groups. Caudally administered 0.5 ml/kg bupivacaine 0.25% plus ketamine or bupivacaine 0.25% plus tramadol 1 mg/kg provided significantly longer duration of analgesia without an increase in the adverse effects when compared to bupivacaine alone.     

Caudal neostigmine with bupivacaine produces a dose-independent analgesic effect in children

PURPOSE: To evaluate the analgesic efficacy and duration of varying doses of caudal neostigmine with plain bupivacaine and its side effects in children undergoing genito-urinary surgery. METHODS: In a randomized double-blind prospective study 80 boys aged two to eight years scheduled for surgical repair of hypospadias were allocated randomly to one of four groups (n = 20 each) and received either only caudal 0.25% plain bupivacaine 0.5 mL.kg(-1) (Group I) or 0.25% plain bupivacaine 0.5 mL.kg(-1) with neostigmine (Groups II-IV) in doses of 2, 3 and 4 microg.kg(-1) respectively. Postoperative pain was assessed for 24 hr using an objective pain score. Blood pressure, heart rate, oxygen saturation, total amount of analgesic consumed and adverse effects were also recorded. RESULTS: The duration of postoperative analgesia in Group I (5.1 +/- 2.3 hr) was significantly shorter than in the other three groups (II -16.6 +/- 4.9 hr; III - 17.2 +/- 5.5 hr; IV - 17.0 +/- 5.8 hr; P < 0.05). Total analgesic (paracetamol) consumption was significantly more in Group I (697.6 +/- 240.7 mg) than in the groups receiving caudal neostigmine (II - 248.0 +/- 178.4; III - 270.2 +/- 180.8 and IV -230.6 +/- 166.9 mg; P < 0.05). Groups II, III and IV were comparable with regards to duration of postoperative analgesia and total analgesic consumption (P > 0.05). Incidence of nausea and vomiting were comparable in all four groups. No significant alteration in vital signs or any other adverse effects were observed. CONCLUSIONS: Caudal neostigmine (2, 3 and 4 microg.kg(-1)) with bupivacaine produces a dose-independent analgesic effect ( approximately 16-17 hr) in children as compared to those receiving caudal bupivacaine alone (approximately five hours) and a reduction in postoperative rescue analgesic consumption without increasing the incidence of adverse effects.     

Comparison of the effects of adrenaline, clonidine and ketamine on the duration of caudal analgesia produced by bupivacaine in children

Sixty boys, aged 1-10 yr, undergoing orchidopexy were allocated randomly to receive one of three solutions for caudal extradural injection. Group A received 0.25% bupivacaine 1 ml kg-1 with adrenaline 5 micrograms ml-1 (1/200,000), group C received 0.25% bupivacaine 1 ml kg-1 with clonidine 2 micrograms kg-1 and group K received 0.25% bupivacaine 1 ml kg-1 with ketamine 0.5 mg kg-1. Postoperative pain was assessed using a modified objective pain score and analgesia was administered if this score exceeded 4. The median duration of caudal analgesia was 12.5 h in group K compared with 5.8 h in group C (P < 0.05) and 3.2 h in group A (P < 0.01). There were no differences between the groups in the incidence of motor block, urinary retention or postoperative sedation.      

The influence of sufentanil and/or clonidine on the duration of analgesia after a caudal block for hypospadias repair surgery in children

The aim of this study was to evaluate whether the addition of clonidine, or sufentanil, or both, to a bupivacaine solution for a caudal block prolonged the period of analgesia after operation in children. Sixty ASA class I or II boys, aged between 8 months and 13 years, admitted for hypospadias repair were enrolled into a prospective randomised study. After induction of general anaesthesia and endotracheal intubation the children were allocated into four groups. Group I received 0.5 mL kg(-1) bupivacaine 0.25% caudally, in addition group II received 1 microg kg(-1) clonidine, group III 0.5 microg kg(-1) sufentanil and group IV 0.5 microg kg(-1) clonidine and 0.25 microg kg(-1) sufentanil. The concentrations of clonidine and sufentanil in group IV were halved to reduce possible side-effects with higher dosages. Analgesia and side-effects were assessed 2, 4, 6, 8 and 12 h after operation. No significant differences were found among the four groups for the pain scores at 2, 4, 6, 8 and 12 h. All groups had a similar frequency of vomiting and a comparable appetite and quality of night rest during the first 24 h following the operation. There was no significant difference in the requirement for additional doses of analgesics. The addition of sufentanil, or clonidine, or both, to bupivacaine for caudal administration provides no additional clinical benefit over bupivacaine alone.