Xiang Si, Daiyin Cao, Rui Shi, Wenliang Song, Riccardo Antolini, Marion Beuzelin, Allegra Blandina, Francesca Botta, F Davi, Giovanni Lorenzo Rumi, Martina Fracazzini, Marta Lauritano, Riccardo La Rosa, Rui Filipe Gomes, Sung Yoon Lim, Ronglin Chen, Jianfeng Wu, Xiangdong Guan, Tai Pham, Christopher Lai, Xavier Monnet
BACKGROUND: The relationship between fluid responsiveness and right-and left-sided congestion remains underexplored. This study aimed to delineate the dynamic behaviour of venous congestion and extravascular lung water index (EVLWI) during a fluid challenge depending on the concomitant changes in cardiac index (CI). METHODS: In patients from three intensive care units, for whom a 500-mL fluid challenge was administered, we retrospectively analysed CI, central venous pressure (CVP), venous excess ultrasound (VExUS), and EVLWI, which had been prospectively recorded. A VExUS congestion point was calculated from 0 to 7 by assigning 1 point to each degree of abnormality for the 4 investigated veins. A subgroup analysis was planned in patients with acute respiratory distress syndrome (ARDS). RESULTS: We analysed 64 patients, of whom 42 (66%) were fluid responders (FR+) defined by a CI increase ≥ 15% with fluid infusion. Before the fluid challenge, CVP was lower in FR + than in fluid non-responders (FR-) (7.3 [2.9-10.3] vs. 10.6 [8.2-13.0] mmHg,respectively, p = 0.002). VExUS grades and congestion points were not different between FR + and FR- (Grade 0: 62% vs. 55%, respectively, p = 0.601; congestion points: 1.0 [0.0-2.3] vs. 2.0 [1.0-3.0], respectively, p = 0.053). EVLWI was also similar between groups. Following fluid administration, VExUS grade deterioration occurred in 5% of FR + versus 73% of FR- (p < 0.001). After the fluid challenge, abnormal VExUS grades were more prevalent in FR - than in FR+ (91% vs. 43%, respectively, p < 0.001), and congestion points were higher (4.0 [3.0-5.0] vs. 1.5 [1.0-3.0], respectively, p < 0.001). CVP increased by 1.4 [0.4-2.4] mmHg in FR + and 2.0 [1.1-3.5] mmHg in FR- (p = 0.064). Among 25 patients with ARDS, EVLWI increased more than in patients without ARDS, in both FR- (by 1.7 [0.9-3.3] vs. 0.7 [0-1.4] mL/kg, respectively, p = 0.046) and FR+ (by 1.0 [-0.6-2.5] vs. 0 [-0.7-0.4] mL/kg, respectively, p = 0.009). CONCLUSION: A fluid challenge worsened venous congestion, assessed by VExUS as well as CVP, in fluid non-responders, while it was not in fluid responders.