From Anaesthesia

Syndicate content
Wiley Online Library : Anaesthesia
Updated: 43 min 13 sec ago

Knowing when to slow down

13. June 2017 - 5:26
Categories: From Anaesthesia

Hyperoxia and surgical site infections

13. June 2017 - 5:26
Categories: From Anaesthesia

Issue Information – Editorial Board

13. June 2017 - 5:26
Categories: From Anaesthesia

A randomised, controlled trial evaluating a low cost, 3D-printed bronchoscopy simulator

12. June 2017 - 6:55
Summary

Low-fidelity, simulation-based psychomotor skills training is a valuable first step in the educational approach to mastering complex procedural skills. We developed a cost-effective bronchial tree simulator based on a human thorax computed tomography scan using rapid-prototyping (3D-print) technology. This randomised, single-blind study evaluated how realistic our 3D-printed simulator would mimic human anatomy compared with commercially available bronchial tree simulators (Laerdal® Airway Management Trainer with Bronchial Tree and AirSim Advance Bronchi, Stavanger, Norway). Thirty experienced anaesthetists and respiratory physicians used a fibreoptic bronchoscope to rate each simulator on a visual analogue scale (VAS) (0 mm = completely unrealistic anatomy, 100 mm = indistinguishable from real patient) for: localisation of the right upper lobe bronchial lumen; placement of a bronchial blocker in the left main bronchus; aspiration of fluid from the right lower lobe; and overall realism. The 3D-printed simulator was rated most realistic for the localisation of the right upper lobe bronchial lumen (p = 0.002), but no differences were found in placement of a bronchial blocker or for aspiration of fluid (p = 0.792 and p = 0.057) compared with using the commercially available simulators. Overall, the 3D-printed simulator was rated most realistic (p = 0.021). Given the substantially lower costs for the 3D-printed simulator (£85 (€100/US$110) compared with > ~ £2000 (€2350/US$2590) for the commercially available simulators), our 3D-printed simulator provides an inexpensive alternative for learning bronchoscopy skills, and offers the possibility of practising procedures on patient-specific models before attempting them in clinical practice.

Categories: From Anaesthesia

Pre-operative brachial plexus block compared with an identical block performed at the end of surgery: a prospective, double-blind, randomised clinical trial

12. June 2017 - 6:46
Summary

We evaluated whether pre-emptive analgesia with a pre-operative ultrasound-guided infraclavicular brachial plexus block resulted in better postoperative analgesia than an identical block performed postoperatively. Fifty-two patients undergoing fixation of a fractured radius were included. All patients received general anaesthesia with remifentanil and propofol. Patients were randomly allocated into two groups: a pre-operative block or a postoperative block with 0.5 ml.kg−1 ropivacaine 0.75%. After surgery, all patients received regular paracetamol plus opioids for breakthrough pain. Mean (SD) time to first rescue analgesic after emergence from general anaesthesia was 544 (217) min in the pre-operative block group compared with 343 (316) min in the postoperative block group (p = 0.015). Postoperative pain scores were higher and more patients required rescue analgesia during the first 4 h after surgery in the postoperative block group. There were no significant differences in plasma stress mediators between the groups. Analgesic consumption was lower at day seven in the pre-operative block group. Pain was described as very strong at block resolution in 27 (63%) patients and 26 (76%) had episodes of mild pain after 6 months. We conclude that a pre-operative ultrasound-guided infraclavicular brachial plexus block provides longer and better analgesia in the acute postoperative period compared with an identical postoperative block in patients undergoing surgery for fractured radius.

Categories: From Anaesthesia

An analysis of the delivery of anaesthetic training sessions in the United Kingdom

6. June 2017 - 8:00
Summary

We analysed data from the electronic rota system CLWRota, covering 2,689,962 anaesthetic sessions between 01/01/2014 and 31/12/2015, in 91 UK Trusts, in order to investigate trainees’ supervision. There were 8209 trainee attachments analysed, during which 618,695 sessions were undertaken by trainees. The number of supervised sessions per week that trainees worked varied considerably (median (IQR [range]) 2.6 (1.6–3.6 [0–10]) for all grades combined), with senior trainees more likely than junior trainees to be supervised for fewer than the three sessions per week mandated by the Royal College of Anaesthetists. The number of supervised sessions was unrelated to Trusts’ size, suggesting that trainees in smaller hospitals receive the same level of supervision as in larger teaching hospitals. Analysis of a dataset of this size should be a good reflection of the delivery of anaesthesia training in the UK.

Categories: From Anaesthesia

Understanding mortality rates after hip fracture repair using ASA physical status in the National Hip Fracture Database

6. June 2017 - 7:55
Summary

Hip fracture is the most common reason for older patients to need emergency anaesthesia and surgery. Up to one-third of patients die in the year after hip fracture, but this view of outcome may encourage therapeutic nihilism in peri-operative decisions and discussions. We used a multicentre national dataset to examine relative and absolute mortality rates for patients presenting with hip fracture, stratified by ASA physical status. We analysed ASA physical status, dates of surgery, death and hospital discharge for 59,369 out of 64,864 patients in the 2015 National Hip Fracture Database; 3914 (6.6%) of whom died in hospital. Rates of death in hospital were 1.8% in ASA 1–2 patients compared with 16.5% in ASA 4 patients. Survival rates for ASA 4 patients on each of the first three postoperative days were: 98.8%, 99.1% and 99.1% (compared with figures of > 99.9% in ASA 1–2 patients over these days). Survival on postoperative day 6 was 99.4% for ASA 4 patients. Nearly half (48.6%) of the 1427 patients who did not have surgery died in hospital. Although technically sound, a focus on cumulative and relative risk of mortality may frame discussions in an unduly negative fashion, discouraging surgeons and anaesthetists from offering an operation, and deterring patients and their loved ones from agreeing to it. A more optimistic and pragmatic explanation that over 98% of ASA 4 patients survive both the day of surgery and the day after it, may be more appropriate.

Categories: From Anaesthesia

Data fabrication and other reasons for non-random sampling in 5087 randomised, controlled trials in anaesthetic and general medical journals

5. June 2017 - 5:10
Summary

Randomised, controlled trials have been retracted after publication because of data fabrication and inadequate ethical approval. Fabricated data have included baseline variables, for instance, age, height or weight. Statistical tests can determine the probability of the distribution of means, given their standard deviation and the number of participants in each group. Randomised, controlled trials have been retracted after the data distributions have been calculated as improbable. Most retracted trials have been written by anaesthetists and published by specialist anaesthetic journals. I wanted to explore whether the distribution of baseline data in trials was consistent with the expected distribution. I wanted to determine whether trials retracted after publication had distributions different to trials that have not been retracted. I wanted to determine whether data distributions in trials published in specialist anaesthetic journals have been different to distributions in non-specialist medical journals. I analysed the distribution of 72,261 means of 29,789 variables in 5087 randomised, controlled trials published in eight journals between January 2000 and December 2015: Anaesthesia (399); Anesthesia and Analgesia (1288); Anesthesiology (541); British Journal of Anaesthesia (618); Canadian Journal of Anesthesia (384); European Journal of Anaesthesiology (404); Journal of the American Medical Association (518) and New England Journal of Medicine (935). I chose these journals as I had electronic access to the full text. Trial p values were distorted by an excess of baseline means that were similar and an excess that were dissimilar: 763/5015 (15.2%) trials that had not been retracted from publication had p values that were within 0.05 of 0 or 1 (expected 10%), that is, a 5.2% excess, p = 1.2 × 10−7. The p values of 31/72 (43%) trials that had been retracted after publication were within 0.05 of 0 or 1, a rate different to that for unretracted trials, p = 1.03 × 10−10. The difference between the distributions of these two subgroups was confirmed by comparison of their overall distributions, p = 5.3 × 10−15. Each journal exhibited the same abnormal distribution of baseline means. There was no difference in distributions of baseline means for 1453 trials in non-anaesthetic journals and 3634 trials in anaesthetic journals, p = 0.30. The rate of retractions from JAMA and NEJM, 6/1453 or 1 in 242, was one-quarter the rate from the six anaesthetic journals, 66/3634 or 1 in 55, relative risk (99%CI) 0.23 (0.08–0.68), p = 0.00022. A probability threshold of 1 in 10,000 identified 8/72 (11%) retracted trials (7 by Fujii et al.) and 82/5015 (1.6%) unretracted trials. Some p values were so extreme that the baseline data could not be correct: for instance, for 43/5015 unretracted trials the probability was less than 1 in 1015 (equivalent to one drop of water in 20,000 Olympic-sized swimming pools). A probability threshold of 1 in 100 for two or more trials by the same author identified three authors of retracted trials (Boldt, Fujii and Reuben) and 21 first or corresponding authors of 65 unretracted trials. Fraud, unintentional error, correlation, stratified allocation and poor methodology might have contributed to the excess of randomised, controlled trials with similar or dissimilar means, a pattern that was common to all the surveyed journals. It is likely that this work will lead to the identification, correction and retraction of hitherto unretracted randomised, controlled trials.

Categories: From Anaesthesia