Risk Factors for Radial-to-Femoral Artery Pressure Gradient in Patients Undergoing Cardiac Surgery With Cardiopulmonary Bypass

Abstract

Objective: To identify risk factors associated with radial-to-femoral pressure gradient during cardiac surgery with cardiopulmonary bypass (CPB).

Design: This is a retrospective, observational study.

Setting: Single specialized cardiothoracic hospital in Montreal, Canada.

Participants: Consecutive patients that underwent heart surgery with CPB between 2005 and 2015 (n = 435).

Interventions: None.

Measurements and main results: A radial-to-femoral pressure gradient occurred in 146 patients of the 435 patients (34%). Based on the 10,000 bootstrap samples, simple logistic regression models identified the 17 most commonly significant variables across the bootstrap runs. Using these variables, a backward multiple logistic model was performed on the original sample and identified the following independent variables: body surface area (m²) (odds ratio [OR] 0.08, 95% confidence interval [CI] 0.030-0.232), clamping time (minutes) (OR 1.01, 95% CI 1.007-1.018), fluid balance (for 1 liter) (OR 0.81, 95% CI 0.669-0.976), and preoperative hypertension (OR 1.801, 95% CI 1.131-2.868).

Conclusion: A radial-to-femoral pressure gradient occurs in 34% of patients during cardiac surgery. Patients at risk seem to be of smaller stature, hypertensive, and undergo longer and more complex surgeries.

Keywords: blood pressure; cardiopulmonary bypass; femoral artery; pressure gradient; radial artery.