Abstract 56: Association between Increased Plasma Catecholamine Levels and Neurogenic Pulmonary Edema in Patients with Subarachnoid Hemorrhage
Background: Neurogenic pulmonary edema (NPE) occurs relatively frequently after aneurysmal subarachnoid hemorrhage (SAH), and excessive release of catecholamines (epinephrine/norepinephrine) has been indicated as its principal cause. The objective of this study is to evaluate the relative contribution of each catecholamine in pathogenesis of NPE.
Methods: Records of 77 SAH patients (23 men/54 women) whose plasma catecholamine levels were measured within 48 h of SAH onset were retrospectively analyzed.
Results: Eight patients (10%) were diagnosed with NPE. Plasma epinephrine (366.9±347.4 vs. 130.3±167.4 pg/mL, p=0.001) and norepinephrine (3481.1±1678.9 vs. 835.5±688.9 pg/mL, p<0.001) levels were significantly higher in the NPE+ group than NPE- group. Demographic comparison revealed that the severity of SAH and cardiac damage/dysfunction was significantly more profound in the NPE+ group. Multivariate logistic regression analysis revealed that increased norepinephrine levels were predictive of NPE (OR, 1.002; 95% CI, 1.001-1.004), but epinephrine levels were not. Linear regression analysis showed that plasma epinephrine and norepinephrine levels were positively correlated. Receiver operating characteristic (ROC) curves showed that threshold values predictive of NPE existed for both catecholamines, and sensitivity/specificity was higher for norepinephrine. After quadrichotomization of patients based on the results of ROC curves, patients whose plasma epinephrine/norepinephrine levels exceeded the threshold values were significantly more likely to experience NPE.
Conclusions: Norepinephrine rather than epinephrine appears to play a more active role in pathogenesis of SAH-induced NPE, although both catecholamines may be involved. Since the number of SAH patients complicated by NPE is relatively small, a multi-center study may be required to clarify the issue.
- © 2012 by American Heart Association, Inc.