Critical care in the emergency department: A physiologic assessment and outcome evaluation

Abstract

Objectives: The changing landscape of health care in this country has seen an increase in the delivery of care to critically ill patients in the emergency department (ED). However, methodologies to assess care and outcomes similar to those used in the intensive care unit (ICU) are currently lacking in this setting. This study examined the impact of ED intervention on morbidity and mortality using the Acute Physiology and Chronic Health Evaluation (APACHE II), the Simplified Acute Physiology Score (SAPS II), and the Multiple Organ Dysfunction Score (MODS).

Methods: This was a prospective, observational cohort study over a three-month period. Critically ill adult patients presenting to a large urban ED and requiring ICU admission were enrolled. APACHE II, SAPS II, and MODS scores and predicted mortality were obtained at ED admission, ED discharge, and 24, 48, and 72 hours in the ICU. In-hospital mortality was recorded.

Results: Eighty-one patients aged 64 +/- 18 years were enrolled during the study period, with a 30.9% in-hospital mortality. The ED length of stay was 5.9 +/- 2.7 hours and the hospital length of stay was 12.2 +/- 16.6 days. Nine (11.1%) patients initially accepted for ICU admission were later admitted to the general ward after ED intervention. Septic shock was the predominant admitting diagnosis. At ED admission, there was a significantly higher APACHE II score in nonsurvivors (23.0 +/- 6.0) vs survivors (19.8 +/- 6.5, p = 0.04), while there was no significant difference in SAPS II or MODS scores. The APACHE II, SAPS II, and MODS scores were significantly lower in survivors than nonsurvivors throughout the hospital stay (p </= 0.001). The hourly rates of change (decreases) in APACHE II, SAPS II, and MODS scores were significantly greater during the ED stay (-0.55 +/- 0.64, -1.02 +/- 1.10, and -0.16 +/- 0.43, respectively) than subsequent periods of hospitalization in survivors (p < 0.05). There was a significant decrease in APACHE II and SAPS II predicted mortality during the ED stay (-8.0 +/- 14.0% and -6.0 +/- 14.0%, respectively, p < 0.001) and equally at 24 hours in the ICU (-7.0 +/- 13.0% and -4.0 +/- 16.0%, respectively, p </= 0.02). The APACHE II and SAPS II predicted mortality approached actual in-hospital mortality at approximately 12 hours and 36 hours after ED admission (in the ICU), respectively.

Conclusions: The care provided during the ED stay for critically ill patients significantly impacts the progression of organ failure and mortality. Although this period is brief compared with the total length of hospitalization, physiologic determinants of outcome may be established before ICU admission. This study emphasizes the importance of ED intervention. It also suggests that unique physiologic assessment methodologies should be developed to examine the quality of patient care, improve the accuracy of prognostic decisions, and objectively measure the impact of clinical interventions and pathways in the ED setting.