Regional Cerebral Oxygen Saturation Monitoring in an Emergency Cesarean Section for Takayasu Arteritis: A Case Report on Utility and Limitations

Takayasu arteritis is a chronic inflammatory vasculitis primarily affecting the aorta and its major branches, such as the subclavian and common carotid arteries (CCAs). Because Takayasu arteritis predominantly affects young women of reproductive age, clinicians may encounter pregnant patients requiring complex perinatal management. In these patients, anesthesia for cesarean section is particularly challenging because peripheral blood pressure often fails to accurately reflect cerebral perfusion pressure due to extensive arterial stenosis. We report the anesthetic management of a 39-year-old pregnant woman with Takayasu arteritis and a history of a left parietal infarction ten years prior, who required an emergency cesarean section. Computed tomography at that time had already revealed severe, long-standing bilateral stenosis of the subclavian and CCAs; notably, the systolic blood pressure in her upper extremities was 60 mmHg lower than in her lower extremities upon admission for delivery. Given her compromised cerebral vascular reserve and the unreliability of peripheral blood pressure, we utilized regional cerebral oxygen saturation (rSO2) as the primary physiological indicator for cerebral perfusion. Although intense patient movement and sweating during labor initially destabilized the rSO2 sensors, measurements were successfully maintained by securing the sensors with additional adhesive tape and constant manual monitoring by dedicated staff. Under spinal anesthesia, we initiated vasopressor administration whenever rSO2 fell 20% below the baseline, a commonly used safety threshold for cerebral desaturation, preventing any subsequent decline of more than 30%. Both the mother and neonate were discharged without neurological sequelae. In patients with Takayasu arteritis and complex vascular lesions, rSO2 monitoring provides a critical real-time assessment of cerebral oxygenation when conventional blood pressure monitoring is unreliable. Clinicians must anticipate technical monitoring challenges in complex cases such as Takayasu arteritis during emergency deliveries and establish proactive backup plans to prevent perioperative neurological complications.