Prospective, randomized trial comparing fluids and dobutamine optimization of oxygen delivery in high-risk surgical patients

Introduction

Preventing perioperative tissue oxygen debt contributes to a better postoperative recovery. Whether the beneficial effects of fluids and inotropes during optimization of oxygen delivery (DO₂) in high-risk surgical patients are due to fluids, inotropes or the combination of the two is not known. We aimed to investigate the effect of fluid optimization, without the use of inotropes, on morbidity.

Methods

A randomized controlled trial with pulmonary artery catheter (PAC)-guided haemodynamic optimization in 50 high-risk patients (elderly with coexistent pathologies) undergoing major elective surgery. Therapy consisted of optimization during the operation and 24 hours postoperatively using either fluids alone (n = 25) or fluids and dobutamine (n = 25), aiming to achieve supranormal values (DO₂ > 600 ml/min/m²). Clinical complications such as pulmonary edema and/or heart failure, acute myocardial infarction, bleeding, thrombosis, fistula and acute renal failure were monitored.

Results

Prevalence of pulmonary edema/heart failure significantly increased in the fluid optimization group in comparison with the dobutamine optimization group in the postoperative period (40% vs 12%, relative risk [RR] 3.33, 95% confidence interval [CI] 1.04–10.7, respectively, P < 0.05). Clinical complications were more frequent in the fluid optimization group than in the dobutamine group (68% vs 28%, RR 2.43, 95% CI 1.22–4.81, P < 0.05). The 30-day mortality rates were 8% in dobutamine optimization group and 20% in the fluid optimization group (RR 2.5, 95% CI 0.53–11.70, not significant).

Conclusion

In high-risk patients undergoing major surgery, PAC-guided hemodynamic optimization using dobutamine determines better outcomes, whereas fluids alone increase the incidence of postoperative complications.