Comparison of ondansetron, metoclopramide and placebo as premedicants to reduce nausea and vomiting after major surgery

In a randomised, double-blind study, we have compared the incidence of postoperative nausea and vomiting in 124 patients undergoing major lower limb orthopaedic surgery following oral premedication with temazapam and ondansetron 8 mg, metoclopramide 10 mg or placebo. They received a standardised epidural and general anaesthetic. An epidural mixture containing bupivacaine 0.1% and fentanyl 10 mg.ml⁻¹ was infused postoperatively. The occurrence of nausea and vomiting was assessed every 4 h for 24 h. The incidence of vomiting significantly decreased from 55% and 43% in the placebo and metoclopramide groups, respectively, to 26% in the ondansetron group (p = 0.03). The incidence of nausea and vomiting in patients who had previously suffered was also significantly reduced from 67% and 68% in the placebo and metoclopramide groups, respectively, to 29% in the ondansetron group (p = 0.035). We conclude that oral premedication with ondansetron 8 mg was superior to metoclopramide 10 mg and placebo in preventing postoperative nausea and vomiting following major orthopaedic surgery in patients given epidural opioid analgesia.     

Prophylactic antiemetics in children undergoing tonsillectomy: high-dose vs low-dose ondansetron

This randomized, double-blind study assessed the impact of two different doses of intraoperative ondansetron on vomiting following tonsillectomy in 240 preadolescent children in a day care surgical setting. After anaesthesia was established by inhalation with N₂O/halothane or intravenously with propofol, the subjects were administered the study drug (50 or 150 μ g·kg⁻¹ ondansetron, maximum dose 8 mg). Anaesthesia was maintained with N₂O/halothane. The greater dose of ondansetron (150 μ g·kg⁻¹) had a lower incidence (36% vs 52%) of postoperative vomiting ( P =0.01). In-hospital emesis was not a problem with only 14% of the subjects vomiting. Eight patients sought medical attention for vomiting after discharge from hospital. In conclusion, 150 μ g·kg⁻¹ ondansetron is a more effective prophylactic antiemetic than 50 & mu;g·kg⁻¹ ondansetron among children undergoing elective tonsillectomy.     

Ondansetron dose response curve in high-risk pediatric patients

Study Objective: To establish a dose-response relationship for ondansetron, and to evaluate any effects of oral premedication with metoclopramide in pediatric patients undergoing tonsillectomy and adenoidectomy and strabismus surgery.

Design: Prospective, randomized, double blind study.

Setting: University affiliated, 280-bed pediatric hospital.

Patients: 320 ASA physical status I and II patients between the ages of 2 and 12 years undergoing tonsillectomy and adenoidectomy or strabismus surgery.

Interventions: Patients were randomized to eight investigational groups. Patients in all eight groups underwent a standard anesthetic. Groups 1, 2, 3, and 4 received intravenous (IV) saline or IV ondansetron at doses of 0.05 mg/kg, 0.1 mg/kg and 0.15 mg/kg, respectively. Groups 5, 6, 7, and 8 received oral metoclopramide 0.15 mg/kg as well as IV saline, and ondansetron 0.05 mg/kg, 0.1 mg/kg, or 0.15 mg/kg. Patients were evaluated for emetic episodes prior to and following discharge.

Measurements and Main Results: All doses of ondansetron 0.05 mg/kg, 0.1 mg/kg, and 0.15 mg/kg were significantly more effective than placebo in reducing the incidence of emesis prior to, following discharge, and during the first 24 postoperative hours (p < 0.001). There were no significant differences in the occurrence of emesis between the groups receiving ondansetron 0.05 mg/kg, 0.1 mg/kg, and 0.15 mg/kg. The addition of oral metoclopramide 0.15 mg/kg had no effect on the incidence of emesis in the ondansetron or placebo study groups.

Conclusions: Ondansetron is an effective medication for the treatment and prevention of postoperative nausea and vomiting, and a dose of ondansetron 0.05 mg/kg is as effective as 0.1 mg/kg and 0.15 mg/kg. Metoclopramide 0.15 mg/kg has no effect on the incidence of postoperative nausea and vomiting.     

Oculocardiac reflex and postoperative vomiting in paediatric strabismus surgery. A randomised controlled trial comparing four anaesthetic techniques

Background : Oculocardiac reflex (OCR) and postoperative vomiting are major complications of paediatric strabismus surgery.
Methods : Children (3–16 yr) undergoing elective strabismus surgery as inpatients were randomly allocated to four anaesthetic techniques: (A) thiopentone induction and isoflurane maintenance; (B) as (A) plus ondansetron 5 mg · m^-2 iv; (C) propofol induction and maintenance; (D) as (C) plus lignocaine 2 mg · kg^-1 iv. All children received prophylactic atropine 0.02 mg · kg^-1 and alfentanil. Nitrous oxide was omitted.
Results : Data on 157 children were analysed. The cumulative incidence of vomiting within 6 and 24 h after surgery with thio-pentone-isoflurane was 26% and 46%, respectively. Adding ondansetron decreased the incidence to 8% and 33%, respectively. This improvement was significant within 6 h only; the number-needed-to-treat was 5.5 (95% CI 2.9–46). Propofol was not different from thiopentone-isoflurane. The addition of lignocaine to propofol was of no benefit. The risk of an OCR was significantly increased with propofol (incidence 40%) compared with isoflurane (14%); the number-needed-to-harm was 3.9 (95% CI 2.6–8).
Conclusions : Thiopental-isoflurane-air/O₂-alfentanil resulted in a moderate risk of vomiting. Adding ondansetron significantly decreased this risk, but 6 children have to be treated for one to benefit in the early postoperative period. Propofol and propofol-lignocaine showed no benefit on vomiting but significantly increased the risk of an OCR despite high-dose prophylactic atropine.     

The use of low-dose mivacurium to facilitate insertion of the laryngeal mask airway

Ninety patients were assigned randomly in a double-blind manner to receive 0.9% sodium chloride, mivacurium 0.04 mg.kg⁻¹ or mivacurium 0.08 mg.kg⁻¹ intravenously, followed by propofol 2.5 mg.kg⁻¹. A laryngeal mask airway (LMA) was inserted 90 s later. The LMA was positioned correctly during the first attempt in 87% of patients and this was not significantly altered by the use of mivacurium. However, mivacurium decreased the incidence of swallowing, coughing, movement and laryngospasm (p < 0.05). LMA insertion was graded as easy in 88% of patients who had mivacurium, compared with 50% in patients who had propofol alone (p < 0.05). The conditions during LMA insertion were similar after 0.04 or 0.08 mg.kg⁻¹ of mivacurium. Patients were apnoeic for a mean (SD) time of 0.67 (0.72) min after propofol alone, compared with 1.72 (1.06) min and 3.05 (1.36) min in patients who also received mivacurium 0.04 and 0.08 mg.kg⁻¹, respectively (p < 0.01). Patients who received mivacurium had a lower incidence of postoperative sore throat (24–30% vs. 53%) (p < 0.05). In conclusion, low-dose mivacurium facilitates LMA insertion and decreases the incidence of postoperative sore throat.     

A comparison of midazolam with trimeprazine as an oral premedicant for children

The effect of oral premedication was investigated in a double-blind, randomised trial in 85 children undergoing tonsillectomy and/or adenoidectomy. Orally administered midazolam 0.5 mg.kg⁻¹ given 30 min pre-operatively was compared with trimeprazine 2 mg.kg⁻¹ given 90 min pre-operatively and a placebo preparation. Compliance, sedation and ease of induction were assessed as were the duration and quality of recovery. Following premedication with midazolam none of the patients was anxious, crying or distressed on leaving the ward, compared with 2/28 in the trimeprazine group and 5/28 in the placebo group (p =0.0007). More patients were calm and quiet on arrival in the anaesthetic room following midazolam than following trimeprazine, with both premedicant agents comparing favourably with placebo. There was no significant difference between the three groups in the time to recovery or the sedation score on discharge to the ward. Midazolam is a safe and effective oral premedicant for children.     

Prophylactic anti-emetic efficacy of ondansetron in laparoscopic cholecystectomy under total intravenous anaesthesiaA randomised, double-blind comparison with droperidol, metoclopramide and placebo

The prophylactic anti-emetic efficacy and safety of pre-operative intravenous ondansetron was evaluated in a randomised, double-blind, comparison with droperidol, metoclopramide and placebo in 160 ASA grade 1 and 2 patients undergoing laparoscopic cholecystectomy under total intravenous anaesthesia. The patients were randomly allocated to receive ondansetron (4 mg), droperidol (1.25 mg), metoclopramide (10 mg) or placebo given as a single intravenous dose immediately before induction of a standardised general anaesthetic. There were no significant differences between the four study groups with regard to the demographic and anaesthetic data, postoperative analgesia, postoperative sedation scores, duration of postoperative hospital stay and incidence of adverse events. The incidence of nausea and vomiting was significantly lower (p < 0.05) between 1 h and 4 h after surgery in the ondansetron group compared with the droperidol, metoclopramide and placebo groups. The incidence of nausea was similar in the four groups in the other study periods: 0-1 h and 4-24 h. The incidence of vomiting was lower in the ondansetron, droperidol and metoclopramide groups than in the placebo group between 1 and 4 h but was the same between 4 and 24 h. As a result of the lower incidence of nausea and vomiting between 1 h and 4 h in the ondansetron group, the overall incidence of nausea and vomiting was lower during the first 24 h after surgery in this group than in the other three groups.     

Ketamine or alfentanil administration prior to propofol anaesthesia: the effects on ProSeal™ laryngeal mask airway insertion conditions and haemodynamic changes in children

This study was designed to compare the effects of ketamine and alfentanil administered prior to induction of anaesthesia with propofol, on the haemodynamic changes and ProSeal laryngeal mask airway^® (PLMA) insertion conditions in children. Eighty children, aged between 3–132 months, were randomly allocated to receive either alfentanil 20 μg.kg⁻¹ (alfentanil group) or ketamine 0.5 mg.kg⁻¹ (ketamine group) before induction of anaesthesia. Ninety seconds following the administration of propofol 4 mg.kg⁻¹, a PLMA was inserted. In the ketamine group, heart rate and mean arterial pressure were higher during the study period compared with the alfentanil group (p < 0.05). The time for the return of spontaneous ventilation was prolonged in the alfentanil group (p = 0.004). In conclusion, we found that the administration of ketamine 0.5 mg.kg⁻¹ with propofol 4 mg.kg⁻¹ preserved haemodynamic stability, and reduced the time to the return of spontaneous ventilation, compared with alfentanil 20 μg.kg⁻¹ during PLMA placement. In addition, the conditions for insertion of the PLMA with ketamine were similar to those found with alfentanil.     

Peroperative treatment with i.v. ketoprofen reduces pain and vomiting in children after strabismus surgery

Background: Strabismus surgery is associated with both pain and vomiting. Ketoprofen is widely used in adults to treat acute pain, but there are only few reports of its use in children. This randomised, double-blind, placebo-controlled, parallel group study was designed to investigate the analgesic effect of i.v. ketoprofen and its effect on the incidence of vomiting in children after day-case strabismus surgery.
Methods: Fifty-nine ASA 1 children, aged 1–12 years, entered the study. After premedication with diazepam and glycopyrronium, anaesthesia was induced with fentanyl and propofol and maintained with isoflurane. After induction the children in the ketoprofen group received 1 mg kg⁻¹ ketoprofen followed by an infusion of 1 mg kg⁻¹ ketoprofen over 2 h. In the placebo group, children received 0.9% saline. The postoperative pain was assessed by the Maunuksela pain score (0=no pain, 10=worst possible pain). All children received fentanyl as a rescue analgesic if the Maunuksela score was ≥3.
Results: In the ketoprofen group the number of fentanyl doses was smaller compared to the placebo group (median 1, quartiles (0–2) vs. 2 (1–3), P =0.047). The children in the ketoprofen group had less pain at 30 min ( P =0.02) and the worst pain observed in the post anaesthesia care unit was lower (3 (0–6) vs. 5 (3–8), P =0.035). The incidence of vomiting was less in the ketoprofen group compared to the placebo group (17% vs. 41%, P =0.036). No serious adverse reactions occurred.
Conclusion: We concluded that ketoprofen administered i.v. during the operation produced analgesia and reduced opioid consumption and the incidence of vomiting in children after strabismus surgery.     

Comparison of rocuronium and suxamethonium for use during rapid sequence induction of anaesthesia

This study was designed to compare the tracheal intubating conditions during a rapid sequence induction of anaesthesia using rocuronium 0.6 ( n  = 61) or 1.0 mg.kg⁻¹ ( n  = 130) or suxamethonium 1.0 mg.kg⁻¹ ( n  = 127) as the neuromuscular blocking drugs. Anaesthesia was induced with fentanyl 1–2 μg.kg⁻¹ and thiopentone 5 mg.kg⁻¹ (median dose) and intubating conditions were assessed 60 s after the administration of the neuromuscular blocking drug by an observer unaware of which drug had been given. Intubating conditions were graded on a three-point scale as excellent, good or poor, the first two being considered clinically acceptable. The study was carried out in two parts. At the end of the first part a comparison between the two doses of rocuronium was carried out when at least 50 patients had been enrolled in each group. The results showed the intubating conditions to be significantly superior with the 1.0 mg.kg⁻¹ dose of rocuronium (p < 0.01). Final comparison between the 1.0 mg.kg⁻¹ doses of rocuronium and suxamethonium showed no significant difference in the incidence of acceptable intubations (96 and 97%, respectively). The incidence of excellent grade of intubations was, however, significantly higher with suxamethonium (80% vs. 65%; p = 0.02). It is concluded that rocuronium 1.0 mg.kg⁻¹ can be used as an alternative to suxamethonium 1.0 mg.kg⁻¹ as part of a rapid sequence induction provided there is no anticipated difficulty in intubation. The clinical duration of this dose of rocuronium is, however, 50–60 min.     

A comparison of acceleromyography and mechanomyography for determination of the dose–response curve of rocuronium in children

In order to compare an acceleromyograph (TOF-Guard^TM) with a mechanomyograph (Grass FT03), the dose–response relationship of rocuronium was simultaneously determined in both arms of 15 children aged 3–11 years during anaesthesia with thiopentone, alfentanil and nitrous oxide. Three subgroups of five children received rocuronium 120, 180 or 240 μg.kg⁻¹ randomly. The effective doses to produce 50% and 95% depression of the first twitch of the train-of-four determined by acceleromyography were 206 and 337 μg.kg⁻¹, respectively, while these values determined by mechanomyography were 151 and 331 μg.kg⁻¹, respectively. The dose–response curve obtained by acceleromyography was steeper and shifted to the right compared with that obtained by mechanomyography (p < 0.0001). The difference between the effective dose producing 50% twitch depression determined by the two devices was highly significant (p < 0.0001). In 13 out of 15 children, the acceleromyograph control train-of-four ratio was significantly greater than unity. Although there was a good correlation ( r  = 0.85) between simultaneous pairs of measurements of neuromuscular block, the acceleromyograph exhibited a bias of −25% relative to the mechanomyograph with wide limits of agreement (−62 to +12%). We conclude that acceleromyographic and mechanomyographic measurements should not be used interchangeably when determining the potency of muscle relaxants.     

Ondansetron reduces nausea and vomiting after paediatric adenotonsillectomy

The efficacy, safety and resource implications of a single intravenous dose of ondansetron (0.1 mg·kg⁻¹, maximum 4 mg) were assessed in a multinational, multicentre, randomized, double-blind, placebo-controlled trial of 427 children aged 1–12 years, undergoing tonsillectomy with/without adenoidectomy. Emesis (retching and/or vomiting) and nausea were analysed separately. Significantly more ondansetron-treated children had no episodes of emesis (127/212 (60%) vs 100/215 (47%); P =0.004) and experienced no postoperative nausea (135/211 (64%) vs 108/213 (51%); P =0.004) in the first 24 h. Ondansetron also reduced the number of emetic episodes ( P <0.001), the time to the first emetic episode ( P <0.001) and overall nausea severity ( P =0.003). Significantly fewer ondansetron-treated children were rescued or withdrawn from the study (5% vs 10%; P =0.042). Fewer ondansetron-treated patients required nursing intervention (34% vs 45%; P =0.007) and the average intervention time was significantly shorter (4.6 vs 8.1 minutes; P =0.001). Resources used to manage PONV were significantly reduced by ondansetron (43% vs 57%; P =0.014).     

Rapid intravenous administration of ondansetron or metoclopramide is not associated with cardiovascular compromise in children

This double blinded, placebo controlled, randomized, and prospective study investigated the effect of the rapid intravenous administration of ondansetron 0.15 mg·kg^?1 or metoclopramide 0.25 mg·kg^?1 on the heart rate, haemoglobin saturation, systolic blood pressure, and diastolic blood pressure in 45 ASA PS I-II children between two and 16 years of age prior to elective tonsillectomy. The study groups were not significantly different with respect to age, weight, or gender. We were unable to detect a change in heart rate, systolic or diastolic blood pressure, or haemoglobin saturation following the rapid administration of ondansetron or metoclopramide. We conclude intravenous ondansetron or metoclopramide (for the prevention of postoperative vomiting) are not associated with cardiovascular instability when administered rapidly to healthy children prior to elective surgery.     

Comparison of caudal block using bupivacaine and ketamine with ilioinguinal nerve block for orchidopexy in children

Forty boys weighing less than 25 kg undergoing unilateral orchidopexy were randomly allocated to receive one of two analgesic regimens. Group C received a caudal epidural block with 0.25% bupivacaine 1 mlkg⁻¹ and preservative-free ketamine 0.5 mgkg⁻¹; Group L received an ilioinguinal nerve block with 0.25% bupivacaine 0.5 mlkg⁻¹ and infiltration of the wound with 0.25% bupivacaine 0.5 mlkg⁻¹. All subjects received diclofenac sodium 1–2 mgkg⁻¹ as a rectal suppository. Postoperative pain was assessed by means of a modified Objective Pain Score and analgesia was administered if this exceeded a value of 4. The median duration of analgesia was 10 h (range 2.6 to > 24 h) in Group C and 2.9 h (range 0.7 to > 24 h) in Group L (p < 0.05). There were no differences between groups in the incidence of motor block, urinary retention, postoperative vomiting or postoperative sedation. Subjects in Group L required significantly more doses of postoperative analgesia than those in Group C (p < 0.05).     

Prophylactic antiemetic therapy with granisetron-dexamethasone combination in women undergoing breast surgery

Background: Dexamethasone decreases chemotherapy-induced emesis when added to an antiemetic regimen. This study was undertaken to evaluate the efficacy of granisetron-dexamethasone combination for the prevention of postoperative nausea and vomiting (PONV) in female patients undergoing general anaesthesia for breast surgery.
Methods: In a randomized, double-blind manner, 135 ASA I patients, aged 40–65 years, were assigned to receive placebo (saline), granisetron 40 μg · kg⁻¹ or granisetron 40 μg · kg⁻¹ plus dexamethasone 8 mg i.v. (n=45 of each) immediately before the induction of anaesthesia. A standard general anaesthetic technique and postoperative analgesia were used. The PONV and safety assessments were performed continuously during the first 3 h (0–3 h) and the next 21 h (3–24 h) after anaesthesia.
Results: A complete response, defined as no PONV and no administration of rescue antiemetic medication, during 0–3 h after anaesthesia was 51%, 82% and 96% in patients who had received placebo, granisetron and granisetron-dexamethasone combination, respectively; the corresponding incidence during 3–24 h after anaesthesia was 56%, 84% and 98% ( P <0.05; overall Fisher's exact probability test). No clinically important adverse events were observed in any of the groups.
Conclusion: Prophylactic use of granisetron-dexamethasone combination is more effective than granisetron alone for the prevention of PONV after breast surgery.     

The minimum effective doses of pethidine and doxapram in the treatment of post-anaesthetic shivering

This study was designed to find the minimum effective doses of doxapram and pethidine to stop post-anaesthetic shivering. Two hundred and twenty healthy patients who shivered following routine surgery were allocated randomly to receive one of 10 doses of doxapram (0.18, 0.23, 0.29, 0.35, 0.41, 0.47, 0.7, 0.93, 1.17 and 1.4 mg.kg⁻¹), one of five doses of pethidine (0.12, 0.18, 0.23, 0.29 and 0.35 mg.kg⁻¹) or saline. Probit analysis demonstrated that the number of patients who stopped shivering with doxapram was independent of the amount of drug given in this dose range. The lowest dose of doxapram (0.18 mg.kg⁻¹) was significantly more effective than placebo (p < 0.01). For pethidine there was a dose-dependent effect on shivering to a maximum of 95% of patients successfully treated with 0.35 mg.kg⁻¹. We conclude that 0.35 mg.kg⁻¹ of pethidine is the minimum dose required to treat post-anaesthetic shivering effectively. We also conclude that 0.18 mg.kg⁻¹of doxapram is as effective as 1.4 mg.kg⁻¹ in the treatment of post-anaesthetic shivering. Further study is required to find the minimum effective dose of doxapram.     

A randomized controlled trial of the antiemetic effect of three doses of ondansetron after strabismus surgery in children

METHODS: One hundred and thirty-one healthy children, aged 31-152 months, undergoing strabismus surgery under general anaesthesia, were randomly allocated to one of four groups: group A received 0.04 mg.kg-1 ( identical with 1 mg.m-2) of ondansetron, group B 0.1 mg.kg-1 ( identical with 2.5 mg.m-2), group C 0.2 mg.kg-1 ( identical with 5 mg.m-2) and group D placebo, given intravenously following induction of anaesthesia. Morphine 0.15 mg.kg-1 was given intravenously, intraoperatively, to provide postoperative analgesia. Hourly records of emetic episodes were made for 24 h. RESULTS: A considerably higher proportion of children suffered emesis in the placebo group compared to the active treatment groups taken together, during the first 8 h of postoperative care (76% vs. 45%, P=0.002). During the first 8 h, only 25% of those in treatment group C suffered emesis, the number-needed-to-treat was 3. There was a statistically significant decrease in the chance of vomiting with increasing dose of ondansetron (P=0.03). By 24 h, the difference in the rate of emesis was less marked but still statistically significant (90% vs. 69%, P=0.03). CONCLUSION: Overall, children given ondansetron had less than one-half the risk of vomiting compared to those given placebo (hazard ratio 0.46, 95% confidence interval 0.29-0.74). The mean number of emetic episodes declined from 2.73 in the placebo group to 1.92 in treatment group C. There was no difference in the incidence of side-effects between groups.     

Incidence and severity of postoperative nausea and vomiting are similar after metoclopramide 20 mg and ondansetron 8 mg given by the end of laparoscopic cholecystectomies

BACKGROUND: Ondansetron has a well documented antiemetic prophylactic effect, whereas in most studies of postoperative nausea and vomiting (PONV), metoclopramide is less efficacious. This can be attributed to the short-lasting effect of metoclopramide when a low dose is given at the beginning of surgery. We wanted to test a 20-mg dose of metoclopramide given at the end of surgery, using ondansetron 8 mg as a reference. METHODS: 122 patients scheduled for elective laparoscopic cholecystectomy under general anesthesia were studied in a randomized, double-blind study design. At the end of the procedure, the patients received either metoclopramide 20 mg or ondansetron 8 mg intravenously. The patients were observed for 24 h for PONV, pain, side-effects and need for rescue antiemetic medication. RESULTS: No significant differences in the incidence of PONV or need for rescue antiemetic treatment was observed in the 0-24 h postoperative study period. The overall incidence of PONV was 43% in the ondansetron group and 47% in the metoclopramide group. The ondansetron patients had a significantly higher incidence of moderate or strong pain during the postoperative observation period (61% vs. 35% in the metoclopramide group) (P < 0.05). No significant differences in side-effects between the groups were observed. CONCLUSIONS: Metoclopramide 20 mg i.v. given at the end of laparoscopic cholecystectomy resulted in a similar incidence of PONV compared with ondansetron 8 mg. The patients receiving metoclopramide had less pain than the patients receiving ondansetron.     

Efficacy of a low-dose spinal morphine with bupivacaine for postoperative analgesia in children undergoing hypospadias repair

Background:  Children undergoing hypospadias repair need to be protected from highly unpleasant sensory and emotional experiences during and after surgery. We designed a double-blinded, randomized, and placebo-controlled study to compare the efficacy of a low-dose (2 μg·kg⁻¹) of intrathecal morphine with placebo for postoperative pain control of children undergoing repair of hypospadias surgery with spinal anesthesia.
Methods:  Fifty-four children were randomly assigned to one of two spinal anesthesia groups. Group M ( n  = 27) received hyperbaric bupivacaine plus 2 μg·kg⁻¹ of preservative-free morphine and group P ( n  = 27) received hyperbaric bupivacaine plus 0.9% NaCl (placebo) under inhalation anesthesia. General anesthetics were discontinued subsequent to the block. The primary outcome was the presence of pain-requiring analgesics during the first 12 h after the spinal block. Side effects were also recorded. The analgesic effects were evaluated by using the Children's Hospital of Eastern Ontario Pain Scale.
Results:  Forty-nine patients completed the trial. Fifteen patients (60%) in group P received supplementary analgesics within the first 12 h compared to only four patients (16.7%) in group M ( P  = 0.005). Mean duration of analgesia was 480 ± 209 and 720 ± 190 min in group P and group M respectively ( P  = 0.009). The groups were similar in postoperative side effects.
Conclusion:  Spinal anesthesia provided by hyperbaric bupivacaine is adequate for distal hypospadias repair in children, but adding 2 μg·kg⁻¹ intrathecal morphine provides better postoperative pain control when compared to placebo in these children.     

Peritonsillar infiltration with bupivacaine and pethidine for relief of post-tonsillectomy pain: a randomised double-blind study

Previous studies of infiltration of local anaesthetics in children undergoing tonsillectomy resulted in conflicting results. The aim of this study was to evaluate the effect of the peritonsillar injection of bupivacaine and pethidine on postoperative pain in children undergoing snare-dissection tonsillectomy. In a double-blind study, 80 children (aged 7–15 years) were randomly divided into two groups receiving peritonsillar injection of either bupivacaine (1 mg.kg⁻¹) and pethidine (1 mg.kg⁻¹) in adrenaline 1 : 200 000 (treatment group) or an equivalent volume of saline (placebo group) pre-operatively. The time needed for first demand of analgesia and analgesic consumption to reduce the visual analogue scale (VAS) for resting throat pain to≤30, the VAS for pain on swallowing, drinking liquid and eating a soft diet, incidence of nausea and vomiting, and the need for rescue anti-emetics in the first 24 h after operation were compared in both groups. The combination of bupivacaine and pethidine could significantly decrease the consumption of analgesics for resting pain at 4, 6, 8, 12, and 24 h after operation but did not reduce pain on swallowing, drinking liquid and eating a soft diet. The times to demand of first dose of analgesic and to first oral intake were not significantly different. The overall satisfaction of patients in relation to relief of postoperative pain was not significantly different between the two groups. Although peritonsillar injection of pethidine and bupivacaine in children reduces the analgesic consumption, it does not affect the dynamic pain state in the first 24 h after snare-dissection tonsillectomy.