Association of preoperative anaemia with cardiopulmonary exercise capacity and postoperative outcomes in noncardiac surgery: a substudy of the Meas…
Authors of this article are:
Bartoszko J, Thorpe KE, Laupacis A, Wijeysundera DN; METS Study Investigators; International and National Coordinators; Central Project Office Operations Committee; CPET Methods Committee; Outcome Adjudication Committee; International Steering Committee.
A summary of the article is shown below:
BACKGROUND: Preoperative anaemia is associated with elevated risks of postoperative complications. This association may be explained by confounding related to poor cardiopulmonary fitness. We conducted a pre-specified substudy of the Measurement of Exercise Tolerance before Surgery (METS) study to examine the associations of preoperative haemoglobin concentration with preoperative cardiopulmonary exercise testing performance (peak oxygen consumption, anaerobic threshold) and postoperative complications.METHODS: The substudy included a nested cross-sectional analysis and nested cohort analysis. In the cross-sectional study (1279 participants), multivariate linear regression modelling was used to determine the adjusted association of haemoglobin concentration with peak oxygen consumption and anaerobic threshold. In the nested cohort study (1256 participants), multivariable logistic regression modelling was used to determine the adjusted association of haemoglobin concentration, peak oxygen consumption, and anaerobic threshold with the primary endpoint (composite outcome of death, cardiovascular complications, acute kidney injury, or surgical site infection) and secondary endpoint (moderate or severe complications).RESULTS: Haemoglobin concentration explained 3.8% of the variation in peak oxygen consumption and anaerobic threshold (P<0.001). Although not associated with the primary endpoint, haemoglobin concentration was associated with moderate or severe complications after adjustment for peak oxygen consumption (odds ratio=0.86 per 10 g L-1 increase; 95% confidence interval, 0.77-0.96) or anaerobic threshold (odds ratio=0.86; 95% confidence interval, 0.77-0.97). Lower peak oxygen consumption was associated with moderate or severe complications without effect modification by haemoglobin concentration (P=0.12).CONCLUSION: Haemoglobin concentration explains a small proportion of variation in exercise capacity. Both anaemia and poor functional capacity are associated with postoperative complications and may therefore be modifiable targets for preoperative optimisation.Copyright © 2019 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.
Check out the article’s website on Pubmed for more information:
This article is a good source of information and a good way to become familiar with topics such as: Cohort Studies;Cross-Sectional Studies;Exercise Test;Hemoglobins;Humans;Oxygen Consumption.