The Eisenmenger syndrome (ES) is a severe form of pulmonary arterial hypertension and arises in congenital heart disease with a systemic-to-pulmonary shunt. Patients with ES have multisystem involvement as a result of chronic hypoxemia with hematologic, skeletal, renal, and neurologic systems, causing significant morbidity and mortality. In contrast to pulmonary arterial hypertension, survival prospects are far superior in patients with ES and a growing number of ES patients are surviving into adulthood. As a result, many face the prospect of incidental surgery. To date, there is no guideline for the perioperative care of ES patients in children and limited data available for adult patients. This review provides an overview of appropriate measures for the safe perioperative care of patients, based on an understanding of the pathophysiological changes that occur in ES.