Predictors of intraoperative hypotension and bradycardia

Christopher C Cheung; Alan Martyn; Norman Campbell; Shaun Frost; Kenneth Gilbert; Franklin Michota; Douglas Seal; William Ghali; Nadia A Khan

doi:10.1016/j.amjmed.2014.11.030

Predictors of intraoperative hypotension and bradycardia

Am J Med. 2015 May;128(5):532-8. doi: 10.1016/j.amjmed.2014.11.030. Epub 2014 Dec 22.

Authors

Christopher C Cheung¹, Alan Martyn¹, Norman Campbell², Shaun Frost³, Kenneth Gilbert⁴, Franklin Michota⁵, Douglas Seal⁶, William Ghali⁷, Nadia A Khan⁸

Affiliations

¹ Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
² Department of Medicine and Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada.
³ Department of Medicine, University of Minnesota and HealthPartners, Minneapolis.
⁴ Department of Medicine, Western University, London, Ontario, Canada.
⁵ Department of Hospital Medicine, Medicine Institute, Cleveland Clinic, Cleveland, Ohio.
⁶ Department of Anesthesia, University of Calgary, Calgary, Alberta, Canada.
⁷ Department of Medicine and Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada; Department of Community Health Sciences, University of Calgary, Calgary, Alberta, Canada.
⁸ Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada. Electronic address: nakhanubc@gmail.com.

PMID: 25541033
DOI: 10.1016/j.amjmed.2014.11.030

Abstract

Background: Perioperative hypotension and bradycardia in the surgical patient are associated with adverse outcomes, including stroke. We developed and evaluated a new preoperative risk model in predicting intraoperative hypotension or bradycardia in patients undergoing elective noncardiac surgery.

Methods: Prospective data were collected in 193 patients undergoing elective, noncardiac surgery. Intraoperative hypotension was defined as systolic blood pressure <90 mm Hg for >5 minutes or a 35% decrease in the mean arterial blood pressure. Intraoperative bradycardia was defined as a heart rate of <60 beats/min for >5 minutes. A logistic regression model was developed for predicting intraoperative hypotension or bradycardia with bootstrap validation. Model performance was assessed using area under the receiver operating curves and Hosmer-Lemeshow tests.

Results: A total of 127 patients developed hypotension or bradycardia. The average age of participants was 67.6 ± 11.3 years, and 59.1% underwent major surgery. A final 5-item score was developed, including preoperative Heart rate (<60 beats/min), preoperative hypotension (<110/60 mm Hg), Elderly age (>65 years), preoperative renin-Angiotensin blockade (angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, or beta-blockers), Revised cardiac risk index (≥3 points), and Type of surgery (major surgery), entitled the "HEART" score. The HEART score was moderately predictive of intraoperative bradycardia or hypotension (odds ratio, 2.51; 95% confidence interval, 1.79-3.53; C-statistic, 0.75). Maximum points on the HEART score were associated with an increased likelihood ratio for intraoperative bradycardia or hypotension (likelihood ratio, +3.64).

Conclusions: The 5-point HEART score was predictive of intraoperative hypotension or bradycardia. These findings suggest a role for using the HEART score to better risk-stratify patients preoperatively and may help guide decisions on perioperative management of blood pressure and heart rate-lowering medications and anesthetic agents.

Keywords: Bradycardia; Hypotension; Risk stratification.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aged
Bradycardia / epidemiology*
Decision Support Techniques*
Elective Surgical Procedures
Female
Humans
Hypotension / epidemiology*
Intraoperative Complications / epidemiology*
Logistic Models
Male
Middle Aged
Multivariate Analysis
ROC Curve
Risk Assessment