Neurogenic Pulmonary Edema following Aneurysmal Subarachnoid Hemorrhage Report of Nine Cases

Abstract

Nine cases of neurogenic pulmonary edema (NPE) following aneurysmal subarachnoid hemorrhage were studied in a recent 1-year period. The incidence of NPE following aneurysmal subarachnoid hemorrhage was 26% during this period; thus, NPE was not a rare complication. The initial signs and symptoms included consciousness disorder, shock, hypertension, hyperventilation, cyanosis, and stridor. The incidence of NPE was highest in patients with grades III and IV according to Hunt and Kosnik, although two patients with NPE were grade II. Hemodynamic changes were studied under Swan-Ganz catheterization in seven cases and the results were analyzed in relation to various factors, such as cardiac output (CO), mean pulmonary arterial pressure (PAP), and mean pulmonary capillary wedge pressure. The mean PAP on initial monitoring was high in five of seven patients. Increased CO was accompanied by decreased systemic vascular resistance and pulmonary vascular resistance in all four patients examined. Hormonal studies at the time of admission in three cases showed an increase of aldosterone in all three, of antidiuretic hormone in two, and of catecholamines in one. In all cases, oxygenation was necessary for 3 to 17 days and NPE improved within 1 to 19 days. The aneurysms were operated on early in every case and the outcomes were surprisingly good. No patients died of NPE per se. It appears that the prognosis of NPE is considerably better than is generally assumed.