Terlipressin versus Norepinephrine to Prevent Milrinone-Induced Systemic Vascular Hypotension in Cardiac Surgery Patient with Pulmonary Hypertension

INTRODUCTION: Milrinone at inotropic doses requires the addition of a vasoconstrictive drug. We hypothesized that terlipressin use could selectively recover the systemic vascular hypotension induced by milrinone without increasing the pulmonary vascular resistance (PVR) and mean pulmonary artery pressure (MPAP) as norepinephrine in cardiac surgery patients. PATIENTS AND METHODS: Patients with pulmonary hypertension were enrolled in this study. At the start of rewarming a milrinone 25 μg/kg bolus over 10 min followed by infusion at the rate of 0.25 μg/kg/min. Just after the loading dose of milrinone, the patients were randomized to receive norepinephrine infusion at a dose of 0.1 μg/kg/min (norepinephrine group) or terlipressin infusion at a dose of 2 μg/kg/h (terlipressin group). Heart rate, mean arterial blood pressure (MAP), central venous pressure, MPAP, systemic vascular resistance (SVR), PVR, cardiac output were measured after induction of anesthesia, after loading dose of milrinone, during skin closure, and in the intensive care unit till 24 h. RESULTS: Milrinone decreased MAP (from 79.56 ± 4.5 to 55.21 ± 2.1 and from 78.46 ± 3.3 to 54.11 ± 1.1) and decreased the MPAP (from 59.5 ± 3.5 to 25.4 ± 2.6 and from 61.3 ± 5.2 to 25.1 ± 2.3) in both groups. After norepinephrine, there was an increase in the MAP which is comparable to terlipressin group (P > 0.05). Terlipressin group shows a significant lower MPAP than norepinephrine group (24.5 ± 1.4 at skin closure vs. 43.3 ± 2.1, than 20.3 ± 2.1 at 24 h vs. 39.8 ± 3.8 postoperatively). There is a comparable increase in the SVR in both group, PVR showed a significant increase in the norepinephrine group compared to the terlipressin group (240.5 ± 23 vs. 140.6 ± 13 at skin closure than 190.3 ± 32 vs. 120.3 ± 10 at 24 h postoperatively). CONCLUSION: The use of terlipressin after milrinone will reverse systemic hypotension with lesser effect on the pulmonary artery pressure.