A prospective randomized comparative study between two different milrinone regimens in adult patients with pulmonary hypertension undergoing cardiac surgery

Context
Milrinone is an inodilator commonly used to improve myocardial function and to decrease pulmonary hypertension.
Aim
The aim of this study was to compare two different regimens of milrinone administration in adult cardiac surgery patients with pulmonary hypertension.
Setting and design
A prospective, randomized, comparative study was conducted in Madinah Cardiac Center, Almadinah Almonourah, Saudi Arabia.
Material and methods
The study included 100 adult patients undergoing cardiac surgery with mean pulmonary artery pressure greater than 25 mmHg, as estimated preoperatively by Doppler echocardiography. The patients were classified randomly into two groups ( = 50): group A and group B. In group A, milrinone was started by infusion at a rate of 0.5 µg/kg/min without a loading dose at the beginning of CPB and continued postoperatively at a rate of 0.5–0.75 µg/kg/min in the cardiac surgical ICU. In group B, milrinone was given as a loading dose of 50 µg/kg over 10 min before weaning from CPB followed by infusion at a rate of 0.5–0.75 µg/kg/min postoperatively in the cardiac surgical ICU.
Statistical analysis used
Data were statistically described in terms of mean ± SD or frequencies and percentages, when appropriate, using the paired -test.
Measurements and main results
Early milrinone using significantly decreased pulmonary artery pressure and pulmonary and systemic vascular resistances; it increased the right ventricular fractional area change, cardiac index, and urine output; and it decreased the serum lactate, pharmacological and mechanical supports, and ICU and hospital length of stay ( < 0.05).
Conclusion
The early administration of milrinone in adult cardiac surgery was associated with better hemodynamic effect, and it decreased the need for pharmacological supports. In addition, it was associated with shorter ICU and hospital length of stay without any side effects related to milrinone.