Nitrous oxide does not increase vomiting after dental restorations in children

The effect of nitrous oxide on postoperative vomiting was evaluated in 330 children who underwent outpatient dental restorations. There were two groups in this single-blind, randomized, controlled study. One group received nitrous oxide during their anesthetic, while the non-nitrous oxide group did not receive nitrous oxide at any time. Anesthesia was induced by inhalation with halothane or with propofol intravenously. The incidence of vomiting for 24 h after surgery was recorded. Overall, the incidence of vomiting was similar, with 30% of the control patients and 35% of the nitrous-treated patients vomiting after their anesthetic. However, in-hospital vomiting was less in the control group: 15% vs 24%, control versus nitrous oxide, P = 0.03. In conclusion, nitrous oxide does not alter postoperative vomiting after halothane anaesthesia for dental restorations in children.

Butorphanol: an opioid for day-care paediatric surgery

The purpose of this study was to compare the side effects and efficacy of equianalgesic doses of morphine (M) and butorphanol (B) in children undergoing similar surgical procedures associated with moderate postoperative pain. We studied 156 healthy children aged 1.5-13 yr who underwent elective inguinal herniorrhaphy or orchidopexy. After induction of anaesthesia subjects were given 150 micrograms.kg-1 M or 30 micrograms.kg-1 B following a randomized, stratified, blocked and double-blind design. A standardized anaesthetic was administered, which included 1.5% halothane, vecuronium, droperidol and mechanical ventilation. The postsurgical four-hour follow-up included assessment of pain, vomiting and respiratory depression. Pain was assessed with mCHEOPS and analgesics were administered when indicated in the recovery room. Each opioid was administered to a group of 78 patients. Within each group, 25 subjects had an iv induction, 21 children had an orchidopexy and 57 had inguinal hernia repairs. The groups were similar with respect to age, weight, and length of surgery. The choice of opioid did not affect recovery times from anaesthesia. Analgesic requirements were similar among the groups. Ten minutes after arrival in the recovery room the B-subjects had a lower pain score than the M-patients. Postoperative vomiting was less among the B-subjects: 14% vs 28%, P = 0.03. Two M-patients required an unscheduled admission to hospital because of vomiting. It is concluded that butorphanol has few advantages over morphine in the population studied.

Nitrous oxide does not increase vomiting in children after myringotomy

The aim of this study was to establish whether nitrous oxide has a clinically important effect on postoperative vomiting in children after myringotomy. We studied 320 healthy children of ages 0.5-13 yr undergoing elective myringotomy and tube insertion. Induction and maintenance of anaesthesia were randomized to inhalation with either 70% N2O/30% O2/halothane or 100%O2/halothane. Surgical technique and postoperative management were not influenced by this study. Vomiting in the recovery room (PAR) and Day Care Surgical Unit (DCSU) was recorded by nurses unaware of the anaesthetic technique. Parents were contacted 24-48 hr after surgery to ascertain the incidence of vomiting after discharge. The groups were similar with respect to demographic data, except that the anaesthesia time was greater among the 158 patients in the N2O-treated group (11 +/- 4 vs 12 +/- 4 min, mean +/- SD). The incidence of vomiting was 13% in both groups. Most of the 42 patients that had emesis only vomited once or twice. The incidence of vomiting was not altered by sex (13% vs 13%) or duration of anaesthesia. The incidence of vomiting increased with increasing age. The children aged less than 3 yr vomited 4% of the time, those aged 3-5 vomited 11% of the time, those aged 6-8 yr vomited 17% of the time, while the incidence of vomiting among those aged 9-13 yr was 31%. Vomiting prolonged the postoperative hospital stay from 75 to 92 min, P < 0.001, ANOVA. In summary, we have been unable to demonstrate that N2O induces vomiting by children after a brief general anaesthetic for myringotomy.

Oral ondansetron decreases vomiting after tonsillectomy in children

Vomiting is a common, unpleasant aftermath of tonsillectomy in children. Intraoperative intravenous ondansetron (OND) reduces vomiting after this operation. Our double-blind, placebo-controlled, randomized investigation studied the effect of the oral form of OND on vomiting after outpatient tonsillectomy in children. We studied 233 healthy children age 2-14 yr undergoing elective tonsillectomy. Subjects were given placebo (PLAC) or OND 0.1 mg.kg-1 rounded off to the nearest 2 mg one hr before surgery. Anaesthesia was induced with either propofol or halothane/N2O. Vecuronium 0.1 mg.kg-1 was administered at the discretion of the anaesthetist. Anaesthesia was maintained with halothane/N2O, 50 micrograms.kg-1 midazolam iv and 1-1.5 mg.kg-1 codeine im. At the end of surgery, residual neuromuscular blockade was reversed with neostigmine and atropine. All episodes of in-hospital emesis were recorded by nursing staff. Rescue antiemetics in the hospital were 1 mg.kg-1 dimenhydrinate iv for vomiting x 2 and 50 micrograms.kg-1 droperidol iv for vomiting x 4. Parents kept a diary of emesis after discharge. Postoperative pain was treated with morphine, codeine and/or acetaminophen. The two groups were similar with respect to demographic data, induction technique and anaesthesia time. Oral OND (n = 109) reduced postoperative emesis from 54% to 39%, P < 0.05. This effect was most dramatic in-hospital, where 10% of the OND-patients and 30% of the PLAC-group vomited, P < 0.05. The OND-subjects required fewer rescue antiemetics, 7% vs 17%, P < 0.05. In conclusion, oral ondansetron decreased the incidence of vomiting after outpatient tonsillectomy in children.

Regional anaesthesia for hernia repair in children: local vs caudal anaesthesia

The purpose of this study was to compare the effect of local anaesthesia (LA) with that of caudal anaesthesia (CA) on postoperative care of children undergoing inguinal hernia repair. This was a randomized, single-blind investigation of 202 children aged 1-13 yr. Anaesthesia was induced with N2O/O2 and halothane or propofol and maintained with N2O/O2/halothane. Local anaesthesia included ilioinguinal and iliohypogastric nerve block plus subcutaneous injection by the surgeon of up to 0.3 ml.kg-1 bupivacaine 0.25% with 5 micrograms.kg-1 adrenaline. The dose for caudal anaesthesia was 1 ml.kg-1 up to 20 ml bupivacaine 0.2% with 5 micrograms.kg-1 adrenaline. Postoperative pain was assessed with mCHEOPS in the anaesthesia recovery room, with postoperative usage of opioid and acetaminophen in the hospital, and with parental assessment of pain with a VAS. Vomiting, time to first ambulation and first urination were recorded. The postoperative pain scores and opioid usage were similar; however, the LA-group required more acetaminophen in the Day Care Surgical Unit. The incidence of vomiting and the times to first ambulation and first urination were similar. The LA-patients had a shorter recovery room stay (40 +/- 9 vs 45 +/- 15 min, P < 0.02). The postoperative stay was prolonged in the CA group (176 +/- 32 vs 165 +/- 26 min, P = 0.02). We conclude that LA and CA have similar effects on postoperative care with only slight differences.

Postoperative sore throat in children and the laryngeal mask airway

Postoperative sore throat is a minor complaint after general anaesthesia of multifactorial aetiology. The purpose of this study was to compare the effect of the laryngeal mask airway (LMA) and endotracheal tube (ETT) on postoperative sore throat in children. We hypothesized that the incidence of sore throat would be less after the use of the LMA. This was a randomized, single-blind study of 112 patients of age 3 to 12 yr undergoing minor peripheral surgery. The groups were similar, except that airway maintenance was either with an LMA or ETT. After induction of anaesthesia with O2, N2O and halothane, an LMA or ETT was inserted. Anaesthesia was maintained with O2, N2O and halothane. At the end of surgery, the ETT was removed in the operating room before airway reflexes had returned. The LMA was removed after the patient's airway reflexes had returned in the recovery room. On the first postoperative day, the parents were contacted and asked whether or not their child had had a sore throat. If a sore throat had been present, the parents rated the discomfort as mild, moderate or severe. The groups were similar with respect to age, weight, sex and duration of procedure. The overall incidence of sore throat was 9%. The difference between the groups (LMA 13% vs ETT 5%) was not statistically significant. All of the reported sore throats were rated as mild. In conclusion, postoperative sore throats after minor paediatric surgery is uncommon. If it does occur, it is mild and the incidence is unaffected by the choice of an LMA or ETT.