Fatal association of tolazoline and dopamine.

A 41-year-old man with an unremarkable medical history aspirated gastric contents during an esophagogastrectomy with intrathoracic gastroesophageal anastomosis for adeno carcinoma of the esophagus. After surgery, he could not be weaned from mechanical ventilation. He was therefore trans ferred to the intensive care unit for ventilatory support. Follow-up chest x-ray films and cultures of sputum supported the diagnosis of aspiration pneumonia. On the fourth postoperative day the patient had an arterial oxygen pressure of 67 mm Hg while receiving a fractional concentration of oxygen in the inspired gas of 0.40 and positive end-expiratory pressure of 18 cm H2O. Therapy with dopamine hydrochloride (12@@g/kg/min) had been started on the previous day to maintain a cardiac index of approximately 3.5 L/min/sq m. Pulmonary arterial pressure, which had been normal immediately after surgery, had been steadily rising and was 90/40 mm Hg; right atrial mean pressure was 15 to 18 mm Hg, and right ventricular pressure was 90/25 mm Hg. In an attempt to reduce the afterload of the right ventricle, tolazoline (2 mg/kg of body weight) was injected as a slow bolus. Systemic arterial pressure immediately fell to 50/30 mm Hg. The infusion of dopamine hydrochloride was initially increased to 20@sg/kg/min, but the arterial pressure fell even further to 38/15 mm Hg. Therapy with dopamine was discontinued, and ephedrine, methoxamine, and fresh frozen plasma were given. Two hours after administration of tolazoline, the blood pressure was 70/40 mm Hg; a new attempt to infuse dop amine hydrochloride (8,Lg/kg/min) resulted in hypotension to 40/15 mm Hg. The arterial pressure returned to 70/40 mm Hg within three to four minutes of discontinuation of the infusion of dopamine. Four hours after the administration of the single dose of tolazoline, arterial pressure was 72/38 mm Hg. There had been no urinary output since the initial episode of hypotension. A new attempt to infuse dopamine hydrochloride (10@g/kg/min) caused the arterial pressure to fall to 38/20 mm Hg; cardiac arrest followed. Permission for autopsy was not granted.