Significant Practice Variation in Oxygen Consumption Values in Congenital Cardiac Catheterization: Cross Sectional Survey in the United States

Oxygen consumption (VO₂) is an essential component to calculate cardiac output using the Fick principle in the congenital cardiac catheterization laboratory (CCCL). Although VO₂ can be measured, the value of VO₂ is frequently assumed based on predictive equations. The objective of this study was to investigate current practice variation in measurement and estimation of VO₂ in CCCL. This was a cross-sectional survey study conducted in January–February 2024. The survey (n = 114) was sent to one interventional cardiologist for each CCCL program in the United States utilizing REDCap. The responses were summarized in a descriptive fashion. Eighty eight programs completed the survey (response rate 77%). Only 13 (15%) programs measured VO₂, though 67 programs (76%) thought VO₂ should be measured for all cases (n = 41) and selective cases (n = 26) and 17 programs thought assumed VO₂ was satisfactory. When VO₂ is referred from predictive equations, most programs primarily used LaFarge (n = 64, 73%), followed by Seckeler (n = 23, 26%). For patients aged < 3 years (where LaFarge equation does not provide VO2 value) in 64 programs using LaFarge, 16 used Seckeler and the remaining 48 programs used a wide range of arbitrary VO₂ values. Most CCCL thought VO₂ should be measured but only 13 (15%) programs actually measured VO₂ in the United States. LaFarge remains frequently used as a predictive equation. There is no standardization of clinical practice in VO₂ measurement/estimation among CCCL in the United States.