Ultrasonographic caval indices do not significantly contribute to predicting fluid responsiveness immediately after coronary artery bypass grafting when compared to passive leg raising.
BACKGROUND
Appropriate fluid management is one of the most important elements of early goal-directed therapy after cardiothoracic surgery. Reliable determination of fluid responsivenss remains the fundamental issue in volume therapy. The purpose of the study was to assess the usefulness of dynamic IVC-derived parameters (collapsibility index, distensibility index) in comparison to passive leg raising, in postoperative fluid management in mechanically ventilated patients with left ventricular ejection fraction ≥ 30 %, immediately after elective coronary artery bypass grafting.


METHODS
Prospective observational case series study including 35 patients with LVEF ≥ 30 %, undergoingelective coronary artery bypass grafting was conducted. Transthoracic echocardiography, passive leg raising and intravenous administration of saline were performed in all study subjects. Dynamic parameters derived from ultrasonographic assessment of the IVC diameter (collapsibility index-CI and distensibility index-DI), cardiac output


RESULTS
There were 24 (68.57 %) responders in the study population. There were no statistical differences between the groups in relation to: clinical parameters, pre- and postoperative LVEF, fluid balance and CVP. Change in cardiac output after passive leg raising correlated significantly with that after the volume expansion (p=0.000, r=0.822). Dynamic IVC derivatives were slightly higher in fluid responders, however this trend did not reach statistical significance. None of the caval indices correlated with fluid responsiveness.


CONCLUSION
Dynamic IVC-derived parameters do not predict fluid responsiveness in mechanically ventilated patients with preserved ejection fraction immediately after elective coronary artery bypass grafting. Passive leg raising is not inferior to volume expansion in differentiating between fluid responders and nonresponders. Immediate fluid challenge after CABG is safe and well tolerated.
['Sobczyk|Dorota|D|', 'Nycz|Krzysztof|K|', 'Andruszkiewicz|Pawel|P|', 'Wierzbicki|Karol|K|', 'Stapor|Maciej|M|']
D000368:Aged D000369:Aged, 80 and over D002302:Cardiac Output D001026:Coronary Artery Bypass D003324:Coronary Artery Disease D004452:Echocardiography D005080:Exercise Test D005260:Female D005440:Fluid Therapy D006801:Humans D007866:Leg D008297:Male D008875:Middle Aged D011446:Prospective Studies D013318:Stroke Volume D016277:Ventricular Function, Left
Fluid responsiveness Coronary artery bypass grafting Passive leg raising Fluid challenge Caval index Inferior vena cava Ultrasound-guided fluid therapy