The perioperative use of inhaled prostacyclins in cardiac surgery: a systematic review and meta-analysis

Purpose Perioperative pulmonary hypertension (PH) is an independent risk factor for morbidity and mortality in cardiac surgery. While inhaled prostacyclins (iPGI 2 s) are an established treatment of chronic PH, data on the efficacy of iPGI 2 s in perioperative PH are scarce. Methods We searched PubMed, Embase, the Web of Science, CENTRAL, and the grey literature from inception until April 2021. We included randomized controlled trials investigating the use of iPGI 2 s in adult and pediatric patients undergoing cardiac surgery with an increased risk of perioperative right ventricle failure. We assessed the efficacy and safety of iPGI 2 s compared with placebo and other inhaled or intravenous vasodilators with random-effect meta-analyses. The primary outcome was mean pulmonary artery pressure (MPAP). Secondary outcomes included other hemodynamic parameters and mortality. Results Thirteen studies were included, comprising 734 patients. Inhaled prostacyclins significantly decreased MPAP compared with placebo (standardized effect size, 0.46; 95% confidence interval [CI], 0.11 to 0.87; P = 0.01) and to intravenous vasodilators (1.26; 95% CI, 0.03 to 2.49; P = 0.045). Inhaled prostacyclins significantly improved the cardiac index compared with intravenous vasodilators (1.53; 95% CI, 0.50 to 2.57; P = 0.004). In contrast, mean arterial pressure was significantly lower in patients treated with iPGI 2 s vs placebo (−0.39; 95% CI, −0.62 to 0.16; P = 0.001), but higher than in patients treated with intravenous vasodilators (0.81; 95% CI, 0.29 to 1.33; P = 0.002). With respect to hemodynamics, iPGI 2 s had similar effects as other inhaled vasodilators. Mortality was not affected by iPGI 2 s. Conclusion The results of this systematic review and meta-analysis show that iPGI 2 s improved pulmonary hemodynamics with similar efficacy as other inhaled vasodilators, but caused a significant small decrease in arterial pressure when compared with placebo, indicating spill-over into the systemic circulation. These effects did not affect clinical outcomes. Study registration date PROSPERO (CRD42021237991); registered 26 May 2021.