Orthodeoxia syndrome: a rare complication of ASD in spinal cord injury

This is a single-subject case report.

The objective is to describe and discuss a rare presentation of orthodeoxia after spinal cord injury in a previously healthy adult with an asymptomatic and undiagnosed atrial septal defect.

This study was conducted at the Tertiary Care Spinal Injuries Center in Sheffield, UK.

An 81-year-old woman who was otherwise healthy and active sustained a polytrauma following a road traffic collision. Her injuries were managed conservatively. As a complication of epidural analgesia, she developed a complete thoracic paraplegia secondary to an epidural hematoma. She was found to have repeated episodes of severe deoxemia, without any significant postural hypotension when attempts were made to sit her up in bed. Detailed investigations were done to ascertain the cause for this deoxemia.

Echocardiography revealed an atrial septal defect; agitated saline contrast transesophageal ultrasound done in various positions revealed interatrial defect with reversal of shunting when the patient was made to sit up in bed.

Orthodeoxia is an uncommon finding in spinal injury patients. Detailed investigations at an early stage of rehabilitation need to be done to rule out cardiac causes after ruling out the common medical complications seen in the acute and subacute phases following spinal cord injury.