Anaesthesia
-
Review Meta Analysis
The influence of clinical risk factors on pre-operative B-type natriuretic peptide risk stratification of vascular surgical patients.
The role of the revised cardiac risk index in risk stratification has recently been challenged by studies reporting on the superior predictive ability of pre-operative B-type natriuretic peptides. We found that in 850 vascular surgical patients initially risk stratified using B-type natriuretic peptides, reclassification with the number of revised cardiac risk index risk factors worsened risk stratification (p < 0.05 for > 0, > 2, > 3 and > 4 risk factors, and p = 0.23 for > 1 risk factor). ⋯ The only independent predictor was B-type natriuretic peptide stratification (OR 5.1, 95% CI 1.8-15 for the intermediate class, and OR 25, 95% CI 8.7-70 for the high-risk class). The clinical risk factors in the revised cardiac risk index cannot improve a risk stratification model based on B-type natriuretic peptides.
-
Review Meta Analysis
Complications associated with peripheral or central routes for central venous cannulation.
We undertook a review of studies comparing complications of centrally or peripherally inserted central venous catheters. Twelve studies were included. ⋯ There was no difference in infection rates. We found that the risks of tip malpositioning, thrombophlebitis and catheter dysfunction favour clinical use of centrally placed catheters instead of peripherally inserted central catheters, and that the two catheter types do not differ with respect to catheter-related infection rates.
-
Review Meta Analysis Comparative Study
Airtraq laryngoscope versus conventional Macintosh laryngoscope: a systematic review and meta-analysis.
The Airtraq laryngoscope is a single-use laryngoscope designed to facilitate tracheal intubation in patients with either normal or difficult airways. The aim of this systematic review and meta-analysis was to compare the Airtraq with the conventional Macintosh laryngoscope. Data were retrieved from Medline, Embase, the Cochrane register of controlled trials, and by a manual search of bibliographies. ⋯ The Airtraq reduced intubation time significantly (mean difference -15 s; 95% CI -25 to -4 s, p < 0.00001) used by both experienced anaesthetists and novices, and it increased the first attempt success rate only in novices (relative risk 1.25; 95% CI 1.05-1.49, p = 0.07). The incidence of oesophageal intubation (relative risk 0.12; 95% CI 0.03-0.48, p < 0.05) was significantly reduced by the Airtraq. We conclude that the Airtraq laryngoscope facilitates a more rapid and accurate intubation, especially when used by novices.
-
Five recent cohort studies have shown a frequency of awareness in paediatric anaesthesia of between 0.2% and 1.2%, but they were not individually large enough to identify risk factors. This study pooled raw data from these five studies to identify factors associated with awareness in children. The outcome of awareness was taken as the cases judged to be most likely awareness cases in each study. ⋯ A combined sample of 4486 anaesthetics revealed 33 cases of awareness. Unadjusted analysis demonstrated weak evidence that nitrous oxide used as an anaesthetic maintenance adjunct was associated with awareness (OR 2.04 (95% CI 0.97-4.33), p=0.06), and some evidence that use of a tracheal tube was associated with awareness (OR 2.78 (95% CI 1.11-6.94), p=0.03). Multivariable regression analysis revealed that nitrous oxide maintenance and use of a tracheal tube were independently associated with awareness (nitrous oxide, OR 2.4 (95% CI 1.08-5.32), p=0.03; tracheal tube, OR 3.0 (95% CI 1.20-7.56), p=0.02).
-
Review Meta Analysis
Association between nitrous oxide and the incidence of postoperative nausea and vomiting in adults: a systematic review and meta-analysis.
Some, but not all studies have suggested intra-operative use of nitrous oxide is correlated with postoperative nausea and vomiting. We performed a meta-analysis of randomised controlled trials to compare the incidence of nausea and vomiting in adults following general anaesthesia with or without nitrous oxide. We retrieved 30 studies (incorporating 33 separate trials) that investigated a 'nitrous oxide group' (total 2297 patients) vs a 'no-nitrous oxide group' (2301 patients). ⋯ In subgroup analysis, the maximal risk reduction was obtained in female patients (pooled relative risk 0.76, 95% CI 0.60-0.96). When nitrous oxide was used in combination with propofol, the antiemetic effect of the latter appeared to compensate the emetogenic effect of nitrous oxide (pooled relative risk 0.94, 95% CI 0.77-1.15). We conclude that avoiding nitrous oxide does reduce the risk of postoperative nausea and vomiting, especially in women, but the overall impact is modest.