Day care anaesthesia: Overview

Abstract
Background Spinal anesthesia is a suitable technique for ambulatory surgery, offering benefits such as rapid recovery and minimal complications. The choice of local anesthetic is a key factor in achieving a rapid turnover in an ambulatory surgery unit. This study compares the safety and effectiveness of hyperbaric prilocaine and hyperbaric bupivacaine in an ambulatory setting. Methods A total of 114 patients undergoing ambulatory surgery were randomly allocated to receive either hyperbaric prilocaine (20mg/mL) or hyperbaric bupivacaine (5mg/mL). Time to first walk, time to discharge, and perioperative complications were compared. Results Eighty-nine patients were analyzed: the median time to first unassisted ambulation was significantly reduced by 41 minutes in the prilocaine group, and the average discharge time was reduced by 29 minutes. Hypotension was the most frequently observed complication, occurring in 17.4% of the prilocaine group and 16.3% of the bupivacaine group, with no statistically significant difference. There was no statistically significant difference between the two groups in other perioperative complications studied. Conclusion Hyperbaric prilocaine is a safe and effective alternative to hyperbaric bupivacaine for ambulatory surgery, offering a rapid onset and intermediate duration, resulting in earlier patient discharge. Improving the perioperative times can make the ambulatory unit more efficient and contribute to cost reduction.

Abstract
Objective: We assessed whether Penthrox (methoxyflurane) can provide better pain relief for elective, outpatient interventional procedures compared with other methods of pain control.

Design: Systematic review.

Data sources: Cochrane Central Register of Controlled Trial, MEDLINE, Emcare, Embase, ClinicalTrials.gov and the Cumulative Index to Nursing and Allied Health Literature were searched from inception to 6 November 2023.

Eligibility criteria: All published studies including randomised controlled trials (RCTs), cohort studies and case-control studies investigating Penthrox for pain relief, during and/or after an interventional procedure, were included.

Data extraction and synthesis: Two independent reviewers identified eligible studies and retrieved data. Risk of bias was assessed using Cochrane Collaboration Risk of Bias V.2.0 and Risk of Bias in Non-randomised Studies of Interventions (ROBINS I) tools. A meta-analysis was not possible due to heterogeneity.

Results: The literature search yielded 1189 records. 12 studies were eligible for inclusion: 5 RCTs and seven non-randomised studies of interventions (NRSIs). Penthrox was used for a range of procedures across five medical specialities: gastroenterology, gynaecology, haematology, orthopaedics and urology. Two RCTs showed a significant reduction in intraprocedural pain when Penthrox was compared with placebo. However, three RCTs where Penthrox was compared with either placebo or intravenous sedation showed no significant differences in pain or comfort level. Similarly, the NRSIs showed variable results. Most patients were satisfied (63% to >98%; seven studies) with Penthrox, and seven out of eight studies reported that the majority of participants would use it again (46.8%-95%; eight studies). No serious adverse events were reported.

Conclusion: Penthrox (methoxyflurane) shows promise as an analgesic for invasive, elective interventional procedures in the outpatient setting, although the relative benefits appear to vary depending on intervention and comparator pain control measures. There is a pressing need for robustly conducted, large, generalisable multicentre RCTs to evaluate the effectiveness of Penthrox.