Pulmonary ultrasound provides a more accurate assessment of pulmonary congestion than wet/dry lung weight in rats

Pulmonary congestion is a common complication in critically ill patients, but its quantification remains challenging. The wet‐to‐dry (W/D) lung weight ratio, widely used in experimental models, is a terminal and semi‐quantitative method. Lung ultrasonography (LU) may offer a non‐invasive and reproducible alternative for assessing pulmonary edema. To evaluate the accuracy and reproducibility of LU compared with the W/D ratio in a rat model of oleic acid–induced lung injury. Thirty Wistar‐Kyoto rats were randomized into injury (oleic acid, n = 15) and control (saline, n = 15) groups. Echocardiography and LU were performed at baseline and 1 h after infusion. B‐line scoring was independently analyzed by two echocardiographers, with reproducibility assessed by Bland–Altman plots. Evans blue dye evaluated vascular permeability. Oleic acid–treated rats showed significantly higher LU scores, B‐line counts, W/D ratios, and Evans blue levels than controls. LU demonstrated good diagnostic performance in detecting lung edema in this experimental model, with excellent inter‐ and intraobserver agreement confirming strong reproducibility. LU proved accurate, reproducible, and non‐terminal for detecting pulmonary congestion in rats, showing good agreement with traditional gravimetric measures and supporting its use for longitudinal assessment of pulmonary edema in experimental research.