Association between persistent tachycardia and tachypnea and in-hospital mortality among non-hypotensive emergency department patients admitted to the hospital.

Objective: Vital sign trends are used in clinical practice to assess treatment response and aid in disposition, yet quantitative data to support this practice are lacking. This study aimed to determine the prognostic value of vital sign normalization.

Methods: Secondary analysis of a prospective cohort of adult emergency department (ED) patients admitted a single urban tertiary care hospital. A random sample of 182 days was chosen, and a manual review of all admissions was undertaken. Persistent tachycardia or tachypnea was defined as failure to decrease to a normal value in the ED. Elevated upon admission was defined as an abnormal value at the last set of vital signs documented. The primary outcome was in-hospital mortality.

Results: 4,878 patients were enrolled and 4.5 (±3.8) sets of vital signs were checked per patient. 1,770 patients were tachycardic and 1,499 were tachypneic. Among tachycardic patients, 941 (53%) were persistently tachycardic and 1,074 (61%) were tachycardic upon admission. Among tachypneic patients 639 (42%) were persistently tachypneic and 768 (51%) were tachypneic upon admission. Mortality was higher in patients persistently tachycardic (5.7% vs. 3.1%, P=0.008) or tachycardic upon admission (5.5% vs. 3.0%, P=0.014). Similar results were found in tachypneic patients (8.3% vs. 4.5%, P=0.003; 7.8% vs. 4.4%, P=0.006).

Conclusion: Persistent tachycardia and tachypnea are associated with an increased risk of mortality in ED patients admitted to the hospital. Further study is necessary to determine if improved recognition or earlier interventions can affect outcomes.