A Comprehensive Review of the Anesthetic Management of Patients with Pulmonary Hypertension Undergoing Cardiac Surgery

Abstract

Background: Pulmonary hypertension (PH) represents a formidable challenge in perioperative medicine, particularly in the context of cardiac surgery, where elevated pulmonary vascular resistance predisposes to right ventricular dysfunction, difficulty in weaning from cardiopulmonary bypass, and increased postoperative morbidity and mortality.

Main body of the abstract: Optimal management requires an integrative strategy encompassing vigilant monitoring, ventilatory adjustments, pharmacologic interventions, and preparedness for mechanical circulatory support. In recent years, attention has focused on the use of inhaled milrinone as a selective pulmonary vasodilator with potential advantages over systemic administration. This review synthesizes evidence from randomized controlled trials, meta-analyses, observational studies, and case reports (2010-2025) to evaluate the role of inhaled and intravenous milrinone, situating these within the broader framework of anesthetic and perioperative management of PH. Inhaled milrinone demonstrates theoretical and mechanistic benefits, including selective pulmonary vasodilation, preservation of systemic vascular resistance, and facilitation of separation from cardiopulmonary bypass, with some studies reporting reductions in extubation time and intensive care unit stay. However, comparative trials remain limited in size, heterogeneity of dosing regimens and timing persists, and definitive improvements in major outcomes such as survival have not been demonstrated.

Conclusion: Inhaled milrinone should not be considered a standalone therapy but rather one element of a multimodal strategy that integrates preoperative optimization, invasive and echocardiographic monitoring, careful anesthetic induction, tailored hemodynamic support, and postoperative vigilance. Future large-scale randomized studies are needed to clarify optimal dosing, comparative effectiveness against other pulmonary vasodilators, and long-term outcomes.