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.


CONCLUSIONS
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.
Department of Interventional Cardiology, John Paul II Hospital, Cracow, Poland. dorotasobczyk@yahoo.com.|Emergency and Admission Department, John Paul II Hospital, Pradnicka 80, 31 202, Cracow, Poland. dorotasobczyk@yahoo.com.
Dorota
D
Sobczyk
Emergency and Admission Department, John Paul II Hospital, Pradnicka 80, 31 202, Cracow, Poland.
Krzysztof
K
Nycz
2nd Department of Anaesthesiology and Intensive Care, Warsaw Medical University, Warsaw, Poland.
Pawel
P
Andruszkiewicz
Cardiovascular Surgery and Transplantology Department, Medical College, Jagiellonian University, Cracow, Poland.
Karol
K
Wierzbicki
Department of Interventional Cardiology, John Paul II Hospital, Cracow, Poland.
Maciej
M
Stapor
D000368:Aged; D000369:Aged, 80 and over; D002302:Cardiac Output; D001026:Coronary Artery Bypass / Q000379:methods*; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D004452:Echocardiography; D005080:Exercise Test / Q000379:methods*; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D006801:Humans; D007866:Leg / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013318:Stroke Volume; D016277:Ventricular Function, Left / Q000502:physiology*
Caval index; Coronary artery bypass grafting; Fluid challenge; Fluid responsiveness; Inferior vena cava; Passive leg raising; Ultrasound-guided fluid therapy