Correlation between ultrasound-measured inferior vena cava diameter and peripherally inserted central catheter measured central venous pressure in low birth weight infants.

Objective: To evaluate the correlation between ultrasound-measured inferior vena cava (IVC) diameter and central venous pressure (CVP) measured by peripherally inserted central catheter (PICC) in low birth weight infants (LBWI) and explore potential influencing factors.

Methods: This retrospective study included 120 LBWI with birth weights below 2500 g who required umbilical vein catheterization at Huadu District People's Hospital of Guangzhou from May 2022 to April 2024. Infants were categorized based on PICC catheterization into two groups. Clinical data, including ultrasound-measured IVC small diameter (SD) and large diameter (LD) at the level of the left portal vein, were collected. The SD/LD ratio (S/L) was calculated, and logistic regression analyses (univariate and multivariate) were performed to identify factors influencing PICC catheterization. Correlations between SD, LD, S/L, and CVP were analyzed.

Results: Multivariate logistic regression identified gestational age, birth weight, SD, S/L, and CVP as significant factors influencing PICC catheterization in LBWI (all P < 0.05). SD and S/L showed a positive correlation with CVP (both P < 0.05). The S/L ratio was significantly correlated with gestational age, birth weight, ventilator mode, tricuspid regurgitation, and vasoactive drug use (all P < 0.05).

Conclusion: Birth weight, SD, S/L ratio, and CVP are significant factors affecting PICC placement in LBWI. There is a notable correlation between ultrasound-measured IVC SD and S/L ratio and PICC-measured CVP in LBWIs.