Profound vasodilatory hypotension in a patient with known empty sella syndrome following cardiac surgery.

A 63-year-old female with known empty sella syndrome underwent coronary artery bypass grafting surgery. She became hypotensive immediately postoperatively and this did not respond to fluid resuscitation and inotropic therapy. Surgical re-exploration was undertaken and did not reveal any surgical cause. Pulmonary artery catheterisation confirmed a profound vasodilatory component to her shock. We believe this was due to unmasking of posterior pituitary hypofunction, in particular vasopressin insufficiency, due to metabolic stress. This rapidly corrected with an exogenous vasopressin infusion.