Monitoring Oxygen Delivery During Cardiopulmonary Bypass: A Preliminary Multinational Practice Survey

Abstract

Objectives: Oxygen delivery (DO₂) is a pivotal factor in maintaining adequate tissue protection during cardiopulmonary bypass (CPB). Despite its clinical significance, there is currently no global consensus regarding standardized DO₂ monitoring or threshold strategies during CPB. This study aimed to evaluate current global practices related to DO₂ monitoring during CPB and to assess awareness, implementation, and perceived clinical benefits, particularly in reducing acute kidney injury.

Design: A cross-sectional international survey.

Setting: Cardiac surgery centers globally, with distribution through platforms including the South West Asia and Africa Chapter of the Extracorporeal Life Support Organization.

Participants: A total of 120 respondents including perfusionists, anesthesiologists, and cardiac surgeons.

Interventions: Not applicable (survey-based observational study).

Measurements and main results: The survey revealed 73.9% of centers actively practiced goal-directed perfusion (GDP), with significantly higher adoption in high-volume centers (>500 cases/year) (82% v 65% in low-volume centers). Monitoring methods varied, with 48.7% of respondents using continuous devices and 37.8% using intermittent calculations. For target parameters, more than 80% of respondents maintained specific DO₂ thresholds, whereas hemoglobin management most focused on 80 to 90 g/L (32.8%), and cardiac index typically ranged from 2.4 to 2.6 L/min/m² (65%). Clinical benefits include reduced acute kidney injury incidence reported by 55% of GDP users, although implementation barriers persisted, particularly financial constraints (45%) and limited resources (38%), preventing a wider adoption of continuous monitoring in resource-limited settings.

Conclusions: These findings reveal significant global variability and underuse of DO₂ monitoring during CPB. Despite emerging evidence supporting the benefits of GDP strategies, widespread adoption remains limited. Cost and limited access to advanced monitoring in low-resource settings were considered the major barriers that prevented continuous monitoring of DO₂ during CPB. These insights highlight an urgent need for international guidelines and standardization to optimize patient outcomes in cardiac surgery.

Keywords: oxygen delivery; perfusion standards; quality improvement.