UNDETECTED CARDIOGENIC-SHOCK IN PATIENTS WITH CONGESTIVE-HEART-FAILURE PRESENTING TO THE EMERGENCY DEPARTMENT

The purpose of this study was to examine the use of lactic acid levels and continuous central venous oxygen saturation (central venous oxime try) to stratify and treat patients with acutely decompensated end-sta ge chronic congestive heart failure (CHF) presenting to the emergency department. This prospective, convenience, non-outcome study was perfo rmed at an urban tertiary care hospital. Patients with end-stage CHF w ith an ejection fraction <30% presenting in decompensated CHF were eli gible for the study. Patients were assessed using the Killip classific ation and New York Heart Association criteria. After lactic acid level s were obtained, patients were managed according to a standardized pro tocol guided by central venous oximetry, The patients were divided int o high lactic acid (n = 22), low lactic acid (n = 5), and control grou ps (stable patients presenting to a cardiology clinic, n = 17) for com parison. There was no statistical difference in vital signs, or Killip and New York Heart Association criteria among the 3 groups. Central v enous oxygen saturation was significantly lower in the high lactic aci d group (32 +/- 12%) than in the normal lactic acid (51 +/- 13%) and c ontrol groups (60 +/- 6%) (p <0.001), After treatment there was a sign ificant decrease in lactic acid (-3.65 +/- 3.65 mM/L) and an increase in central venous oxygen saturation (32 +/- 13%) in the high lactic ac id group compared with the normal lactic acid group (p <0.001). A sign ificant subset of patients with decompensated end-stage CHF present to the emergency department in occult shock and are clinically indisting uishable from patients with mildly decompensated CHF and stable CHF, O nce identified, these patients require aggressive alternative manageme nt and disposition. Further study is necessary to identify whether thi s intervention impacts morbidity, mortality, and health care resource consumption. (C)1998 by Excerpta Medica, Inc.