| Methods |
Randomized controlled trial at St Thomas' Hospital London, UK. Outcome assessor in recovery room was blinded. |
| Participants |
82 pregnant women. ASA group I or II. Gestational age <12 weeks. |
| Interventions |
Group 1 (enflurane): Induction with methohexitone 2mg/kg. Maintenance with 70% nitrous oxide in oxygen and 3% enflurane until cervical dilation completed.
Group 2 (fentanyl): fentanyl 1.5mcg/kg IV followed by methohexitone 2mg/kg. Maintenance with 70% nitrous oxide in oxygen and incremental doses of methohexitone.
All participants: Vacuum aspiration (Karmen curettage). |
| Outcomes |
Blood loss, duration of operation, minor complications such as coughing, salivation, hiccup, laryngeal stridor, and limb movements. Recovery observations: Recovery of consciousness assessed by time of first eye opening in response to their name. Nausea, vomiting, abdominal pain (nil, slight, moderate/severe) and need for medication (yes/no) after operation during the first hour and each subsequent hour until discharge. |
| Notes |
Unclear study length, method of randomization and allocation concealment. Unclear who was blinded other than the recovery room outcome assessor. Group sequential design to determine trial size. Anestethic agent was considered a failure if moderate to severe nausea occured. The upper boundary was crossed after 74 patients indicating a statistical significnt difference between the anesthesia groups at the 5% level using a one‐sided test.
The author states that the 82 patients were included; 43 in the enflurane and 39 in the fentanyl group. However, patients table 2 with abdominal pain add up to 47 and 110% in the enflurane group.
Severe complications, defined as delaying the procedure, occured in 4 patients; respiratory depression in one patient in the fentanyl group, prolonged coughing with salivation in one patient in the enflurane group and 2 patients in the fentanyl group.
The author could not be succeessfully contacted to clarify unclear information. |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Allocation concealment? |
Unclear risk |
B ‐ Unclear |
