What is the significance of portal pulmonary hypertension How are these patients managed in the pretransplant period

In contrast to mosttransplant recipients, portal pulmonary hypertension (PPHTN) patients have an increased risk of death because of right ventricular failure in the peritransplantation period. Physicians are uncertain which PPHTN patients may undergo transplantation because there are no patient characteristics that clearly predict outcome. Patients with moderate to severe PPHTN should not be considered candidates until they undergo a trial of vasodilator therapy. The cause of pulmonary hypertension in liver failure patients is unknown, but the disease shares many similarities with primary pulmonary hypertension. Tissue hypoxia likely plays a role. The pulmonary circulation has increased vascular resistance that is transmitted back to the right heart and liver. The pulmonary vessels of patients with PPHTN are unable to accommodate increased blood flow during periods of aggressive blood transfusion and during the hyperdynamic postreperfusion phase, potentially resulting in acute right ventricular failure. Rapid dilation of the right ventricle can also compress the right coronary vessels, producing myocardial ischemia and infarction. Pulmonary hypertension will not resolve in all patients who were successfully transplanted with a new liver.

Vasodilators reduce pulmonary artery pressures and prolong survival in some pulmonary hypertension patients. The prostaglandin epoprostenol (Flolan) can reduce pulmonary artery pressures when given as a chronic infusion and has been used to bridge patients to transplantation. Nitric oxide inhaled in doses up to 80 ppm also acutely reduces pulmonary artery pressures in a small number of PPHTN patients and has been used in the operating room to reduce pulmonary artery pressures. More recently, sildenafil (Revatio) has been implemented as an oral agent to reduce pulmonary hypertension in transplant candidates.

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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