Hands off Trans-Femoral Venous Intra-Abdominal Pressure Estimates in Children: Results of a Sobering Single-Center Study

Background: For a long time, trans-femoral venous pressure (FVP) measurement was considered a simple alternative for estimating intra-abdominal pressure (IAP). Since intravesical [IVP] and intragastric [IGP] pressure measurements are sometimes contraindicated for anatomical and pathophysiological reasons, FVP raised hopes, especially among pediatricians. Pediatric FVP validation studies have never been published; recent results from adult studies cast doubt on their interchangeability. Therefore, we compared for the first time the measurement agreement between FVP and IVP and IGP in children. Material and methods: We prospectively compared FVP with IVP and IGP, according to the Abdominal Compartment Society validation criteria. Additionally, we analyzed the agreement as a function of IAP or right heart valve regurgitation and pulmonary hypertension. Results: In a real-life PICU study design, n = 39 children were included (median age 4.8 y, LOS-PICU 23 days, PRISM III score 11). In n = 660 FVP–IGP measurement pairs, the median IAP was 7 (range 1 to 23) mmHg; in n = 459 FVP–IVP measurement pairs, the median IAP was 6 (range 1to 16) mmHg. The measurement agreement was extremely low with both established methods (FVP–IGP: r(2) 0.13, mean bias −0.8 ± 4.4 mmHg, limits of agreement (LOA) −9.6/+8.0, percentage error (PE) 55%; FVP–IVP: r(2) 0.14, bias +0.5 ± 4.2 mmHg, limit of agreement (LOA) −7.9/+8.9, percentage error (PE) 51%). No effect of the a priori defined influencing factors on the measurement agreement could be demonstrated. Conclusions: In a study cohort with a high proportion of critically ill children suffering from IAH, FVP did not agree reliably with either IVP or IGP. Its clinical use in critically ill children must therefore be strongly discouraged.