Extracorporeal membrane oxygenation rescue therapy in a case of portopulmonary hypertension during liver transplantation: a case report

Portopulmonary hypertension has been reported in 2% to 9% of candidates for liver transplantation (OLT). If it is moderate to severe, it represents a contraindication to the procedure until pulmonary vasodilatative therapy has been optimized. We report the case of a 43-year-old man, scheduled for OLT due to alcoholic cirrhosis with hemosiderosis. His Model for End-Stage Liver Disease was 25 at that time. The preoperative evaluation showed a severe alteration of diffusion (pO2 68 mm Hg), without hepatopulmonary syndrome or portopulmonary hypertension (PPH) upon basal and dobutamine stress echocardiography. At the beginning of the OLT the hemodynamic profile showed mean pulmonary artery pressure (mPAP) 38 mm Hg, wedge pressure (WP) 19 mm Hg, cardiac output (CO) 9.1 L/min, pulmonary vascular resistance (PVR) 166 dyne s/cm(5), transpulmonary gradient (TPG) 19 mm Hg, which lead us to promptly initiate inhaled nitric oxide (iNO) and intravenous epoprostenol 2 to 5 ng/kg/min. Upon graft reperfusion the hemodynamic profile was: mPAP 47 mm Hg, WP 23 mm Hg, CO 14.2 L/min, PVR 135 dyne s/cm(5), TPG 24 mm Hg, and at the end of surgery, mPAP 39 mm Hg, WP 20 mm Hg, CO 10.6 L/min, PVR 123 dyne s/cm(5), TPG 19 mm Hg. On postoperative day (POD) 3, we observed severe worsening of PPH: mPAP 60 mm Hg, WP 10 mm Hg, CO 9.8 L/min, PVR 395 dyne s/cm(5), TPG 50 mm Hg even with maximal pulmonary vasodilatatory therapy (ambrisentan 5 mg, intravenous sildenafil 20 mg × 3 and epoprostenol 22 ng/kg/min, iNO). Severe acute respiratory distress syndrome (ARDS) was presents. Therefore we decided to begin veno-venous extracorporeal membrane oxygenation (v-v ECMO) to correct the hypoxic vasoconstriction. Subsequent weaning from inotropic support with iNO and epoprostenol was possible on POD 7 due to mPAP 42 mm Hg, WP 15 mm Hg, CO 7.9 L/min, PVR 273 dyne s/cm(5), and TPG 27 mm Hg. On POD 11 he was weaned from ECMO due to: mPAP 40 mm Hg, WP 16 mm Hg, CO 6.5 L/min, PVR 295 dyne s/cm(5) and TPG 24 mm Hg. The patient was extubated on POD 17. The cardiac catheterization 1 month after OLT showed: mPAP 28 mm Hg, WP 13 mm Hg, CO 5.4 L/min, PVR 220 dyne s/cm(5) and TPG 15 mm Hg. ECMO rescue therapy in this "extreme" case allowed us to correct hypoxemia responsible for worsening of pulmonary hypertension allowing time to reach the goal of vasodilatatory therapy.