PREDICTION OF OUTCOME FOR CRITICALLY ILL PATIENTS WITH UNEXPLAINED HYPOTENSION

Objectives: To determine the clinical variables that affect the progno sis of critically ill patients with sustained unexplained hypotension, A further goal was to develop a prognostic scoring system based on cl inical data available at the onset of hypotension, Design: Prospective cohort study. Setting: The intensive care units (ICUs) of an academic medi cal center. Patients: One hundred one adult ICU patients with su stained (>60 mins) unexplained hypotension, Using the initial 50 patie nts (derivation set), a prognostic score was developed that was then t ested in the next 51 patients (validation set). Interventions: None. M easurements and Main Results: The main outcome variable was death or h ospital discharge, The overall hospital mortality in the combined sets was 58%, Using a multivariable model we identified three independent (p<.05) predictors of hospital mortal ity, including the Acute Physiol ogy and Chronic Health Evaluation (APACHE) II score at the time of hyp otension, the time from hospital admission to hypotensive episode, and hospital admission for surgery or treatment of malignancy, These vari ables were weighted and combined to create a Hypotension Score which s eparated patients in the combined sets into three prognostic groups: a ) Hypotension Score of <40, mortality 7%, (n = 27); b) Hypotension Sco re of 40 to 64, mortality 70%, (n = 50); and c) Hypotension Score of g reater than or equal to 65, mortality 92%, (n = 24), The area under th e receiver operat ing characteristic curve was .85 for the derivation set and .83 for the validation set vs. 76 for the APACHE II score alon e. Conclusions: The prognosis of hypotension in the critical care sett ing is highly variable, but can be predicted from patient characterist ics.