A Comparison of Inhaled Nitric Oxide Versus Inhaled Epoprostenol for Acute Pulmonary Hypertension Following Cardiac Surgery

Background: Direct comparisons of inhaled nitric oxide (iNO) to inhaled epoprostenol (iEPO) in patients with acute pulmonary hypertension (PHT) following cardiac surgery are lacking. Objective: To compare the relative efficacy, safety, and cost of iNO versus iEPO in patients with acute PHT following cardiac surgery. Methods: This is a single-center, retrospective, observational, cohort study comparing iNO to iEPO for acute postoperative PHT following cardiac surgery. The primary outcome was reduction of mean pulmonary artery pressure (mPAP) to < 30 mm Hg, 6 hours after ICU admission from the operating room. Secondary outcomes, included ICU and hospital length of stay, duration of mechanical ventilation, bleeding complications, hypotension, in-hospital mortality, and cost. Results: A total of 98 patients met inclusion criteria (iNO, n = 49; iEPO, n = 49). There was no difference in the primary outcome of reduction of mPAP to < 30 mm Hg 6 hours after ICU admission (iNO, 33 [67%] vs iEPO, 35 [71%]; P = 0.83) or in the incidence of adverse events collected (iNO, 10 [20%] vs iEPO, 11 [22%]; P = 1.00). Based on cost estimates, the median cost of iEPO per patient was $363.53 ($226-$864.60) versus $2562.50 ($1875-$8625) for iNO (P < 0.01). Conclusions: The relative efficacy of iEPO appeared to be similar to that of iNO in reducing mPAP following cardiac surgery, in this retrospective review. Significant cost savings were associated with the use of iEPO.