Intravenous Versus Inhaled Milrinone in Patients with Known Pulmonary Hypertension Undergoing Cardiac Surgery: A...

Area of Science:

• Cardiology
• Anesthesiology
• Pharmacology

Background:

• Pulmonary hypertension (PH) poses significant risks during cardiac surgery.
• Milrinone is used to manage hemodynamic instability in these patients.
• Evidence comparing inhaled and intravenous milrinone for PH in cardiac surgery is limited.

Purpose of the Study:

• To evaluate the hemodynamic effects and vasopressor needs of adult cardiac surgery patients with PH treated with inhaled versus intravenous milrinone.
• To synthesize evidence from prospective studies and randomized controlled trials (RCTs).

Main Methods:

• Pooled analysis of 5 prospective studies, including 4 RCTs, with a total of 400 patients.
• Comparison of hemodynamic parameters between inhaled and intravenous milrinone groups.

Main Results:

• No significant difference in mean pulmonary artery pressure (MPAP) between groups (MD: -4.80).
• Inhaled milrinone showed increased systemic vascular resistance index (SVRI) (MD: 259.21) and reduced pulmonary capillary wedge pressure (MD: -4.64).
• No differences observed in mean arterial pressure, pulmonary vascular resistance, cardiac index, or central venous pressure. Risk of bias was moderate/some concern.

Conclusions:

• Inhaled milrinone did not demonstrate significant advantages over intravenous milrinone for MPAP and SVR in PH patients undergoing cardiac surgery.
• Inhaled milrinone may offer benefits in maintaining mean arterial pressure and improving oxygenation.
• Further well-powered RCTs are needed due to study limitations and variability in drug administration.