Efficacy of early goal-directed therapy using FloTrac/EV1000 to improve postoperative outcomes in patients undergoing off-pump coronary artery bypass surgery: a randomized controlled trial

Background: Early goal-directed therapy (EGDT) using FloTrac reduced length of stay (LOS) in intensive care (ICU) and hospital among patients undergoing coronary artery bypass graft (CABG) with a cardiopulmonary bypass (CPB). However, this platform in off-pump CABG (OPCAB) has received scant attention, so we evaluated the efficacy of EGDT using FloTrac/EV1000 as a modality for improving postoperative outcomes in patients undergoing OPCAB.Methods: Forty patients undergoing OPCAB were randomized to the EV1000 or Control group. The Control group received fluid, inotropic, or vasoactive drugs (at the discretion of the attending anesthesiologist) to maintain a mean arterial pressure 65-90 mmHg; central venous pressure 8-12 mmHg; urine output ≥ 0.5 mL·kg-1·h-1; SpO2 > 95%; and hematocrit ≥ 30%. The EV1000 group achieved identical targets using information from the FloTrac/EV1000. The goals included stroke volume variation (SVV) < 13%; stroke volume index (SVI) of 33-65 mL·beat-1·m-2 and cardiac index (CI) of 2.2-4.0 L·min-1·m-2; and systemic vascular resistance index (SVRI) of 1,500‑2,500 dynes s-1·cm-5·m-2.Results: The EV1000 group had a shorter LOS in ICU (mean difference -31.6 h, 95% CI -42.8 to -20.3; P < 0.001). The ventilator time for both groups was comparable (P = 0.316), but the hospital stay for the EV1000 group was shorter (mean difference -1.4 d, 95% CI -2.1 to -0.6; P < 0.001).Conclusions: EGDT using FloTrac/EV1000 compared to conventional protocol reduces LOS in ICU and hospital among patients undergoing OPCAB.Trial registration: This study was retrospectively registered at www.ClinicalTrials.gov (NCT04292951) on 3 March 2020.