Rectal pentothal in pediatric anesthesia. A comparative clinical study

Rectal ketamine and midazolam for premedication in pediatric dentistry

Rectally administered midazolam (0.30 mg/kg) and ketamine (5 mg/kg) were compared for preanesthetic medication in children undergoing dental extractions. Sixty patients between the ages 2 and 9 years were randomly allocated to three groups in this double-blind study. In one group of patients who received ketamine rectally, intravenous midazolam (0.05 mg/kg) also was administered immediately after induction of anesthesia. The results from this trial show that 30 minutes after rectal administration of the two drugs, good anxiolysis, sedation, and cooperation were obtained in most patients. Although midazolam appeared to be marginally more efficacious than ketamine in the majority of assessments made and seemed to have less adverse effects, no statistically significant differences could be shown. Ketamine showed a slight decrease and midazolam a slight increase in average blood pressures after premedication. These blood pressure differences were, however, considered to be of little clinical importance.

Preanesthetic medication with rectal midazolam in children undergoing dental extractions

Three different dosages (0.25, 0.35, and 0.45 mg/kg) of rectally administered midazolam were compared with each other and with placebo for preanesthetic medication in children undergoing dental extractions. Eighty patients between the ages of 2 and 10 years were randomly allocated into four groups in this double-blind study. The results from this trial show that 30 minutes after rectal administration of all doses of midazolam, good anxiolysis, sedation, and cooperation were obtained in most patients. A high prevalence (23%) of disinhibition reactions was observed, particularly in the 0.45 mg/kg group. For this reason, 0.25 or 0.35 mg/kg appears to be the dose of choice when rectal midazolam is used for premedication in children.

Effects of rectal thiopentone and methohexitone on carbon dioxide tension in infant anaesthesia with spontaneous ventilation

The influence of rectal administration of barbiturates on PCO2 during mask anaesthesia with spontaneous ventilation was studied in 72 infants. The age of the patients ranged between 6 and 24 months and they were all subjected to minor paediatric surgery. The patients were divided into four equally large groups: a control group receiving no premedication, a group receiving rectal thiopentone 30 mg X kg-1 and two groups receiving methohexitone either 20 or 30 mg X kg-1. In all patients PCO2 was measured in an arterialized capillary blood sample obtained during stable anaesthesia with oxygen, nitrous oxide and halothane before and after surgery. After rectal induction with barbiturates, the mean PCO2 was significantly higher in the different barbiturate groups than in the control group (P less than 0.05). The mean PCO2 value +/- s.d. in kPa for the control group was 5.6 +/- 0.7, for the group receiving thiopentone 30 mg X kg-1 6.5 +/- 1.6, for the groups receiving methohexitone 20 or 30 mg X kg-1 6.1 +/- 1.2 and 6.3 +/- 1.1, respectively. It is concluded that the combination of rectal induction with barbiturates and mask anaesthesia with oxygen, nitrous oxide and halothane carries an increased risk of hypoventilation in infants under 2 years of age.