Anesthetic management of Platypnea–orthodeoxia syndrome in a young patient with residual atrial septal defect following congenital heart surgery

Abstract Background Platypnea–orthodeoxia syndrome (POS) is a rare condition causing dyspnea and hypoxemia that worsen in the upright position and improve when supine. While often reported in elderly patients, POS in young adults, particularly due to residual atrial septal defects (ASD) after congenital heart surgery, is uncommon. Case presentation We present a 24-year-old woman with POS caused by a residual ASD following congenital heart surgery. Agitated saline contrast transthoracic echocardiography confirmed marked right-to-left shunting exacerbated by positional change and Valsalva maneuver. Anesthetic management focused on minimizing shunt flow by maintaining systemic vascular resistance, avoiding hypoxia, hypercarbia, and acidosis, and carefully adjusting ventilation parameters. Transesophageal echocardiography was utilized for shunt evaluation and device placement. Additionally, continuous cerebral oximetry was monitored for possible ischemic changes associated with paradoxical embolisms. The patient underwent successful percutaneous ASD closure without complications. Conclusion This rare case of young-onset POS highlights the importance of understanding the dynamic shunt physiology and vigilant intraoperative monitoring to ensure patient safety.