British journal of anaesthesia
-
We have compared cardiorespiratory variables in anaesthetized piglets whose lungs were ventilated with oxygen in nitrous oxide (N2O group) or nitrogen (N group) after right ventricular carbon dioxide boluses (0.5 or 1 ml kg-1; n = 12) or slow graded injections (n = 6). Boluses affected all variables studied significantly (P < 0.05) except mean systolic arterial pressure. Significant changes in PE'CO2 (P = 0.012) and PaO2 (P = 0.048) values were observed in the N2O group. ⋯ Volumes and time required to induce a 50% increase in mean pulmonary arterial pressure differed significantly between groups (P < 0.05). We conclude that nitrous oxide worsened the effects of rapid and slow carbon dioxide emboli on cardiopulmonary variables. Rapid carbon dioxide embolism altered respiratory and haemodynamic variables, while slow carbon dioxide embolism changed only respiratory variables.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Recovery after desflurane anaesthesia in the infant: comparison with isoflurane.
We have studied 20 infants, aged 2.5-8 weeks, undergoing general anaesthesia for pyloromyotomy with either desflurane or isoflurane. Patients were anaesthetized with equivalent 1 MAC values for age and agent. A blinded observer recorded times to breathing, swallowing, movement, extubation and side effects after discontinuation of the agent. ⋯ In addition, postoperative apnoea was documented in the isoflurane group but not in those infants receiving desflurane. There was no laryngospasm after extubation in either group. We conclude that desflurane possesses useful characteristics for recovery conditions in the infant and may be particularly useful in the ex-premature infant prone to apnoea and ventilatory depression.
-
Randomized Controlled Trial Clinical Trial
Effect of neuromuscular block on depth of anaesthesia as measured by the auditory evoked response.
In a double-blind, randomized, controlled, prospective study, we have investigated the effects of vecuronium and laryngoscopy on the auditory evoked response (AER) of the electroencephalogram (EEG) in 40 ASA I and II patients under steady state anaesthesia. After stable anaesthesia had been achieved with 1.0 MAC of isoflurane and nitrous oxide in oxygen, patients were allocated randomly to receive two separate doses of vecuronium 0.05 mg kg-1 or saline. The AER was recorded before and after each dose and then after 20-s laryngoscopy in each group to determine any changes in the early cortical components of the AER waveform (Pa and Nb). ⋯ There were correspondingly significant haemodynamic responses to laryngoscopy in both groups. We conclude that neuromuscular block with vecuronium does not affect depth of anaesthesia as measured by the AER in either stimulated or unstimulated patients. In addition, we have demonstrated clearly the arousal effect of laryngoscopy on the AER.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Comparison of ondansetron and prochlorperazine for the prevention of nausea and vomiting after adenotonsillectomy.
This study has compared the incidences of nausea, vomiting and headache after ondansetron 0.06 mg kg-1 i.v., prochlorperazine 0.2 mg kg-1 i.m. and prochlorperazine 0.1 mg kg-1 i.v. given during induction of general anaesthesia to 282 patients undergoing adenotonsillectomy. The cardiovascular effects of the drugs were similar. ⋯ Nausea and vomiting in the same patient was reduced from 29% to 2% by i.v. ondansetron (P < 0.0005) and to 3% by i.m. prochlorperazine (P < 0.0005), and appeared to be less severe in these groups. Headache was most frequent after i.v. ondansetron (35%: P < 0.05), but occurred with similar frequency after i.m. prochlorperazine (32%) and i.v. prochlorperazine (29%).