Background: Shock is a common life-threatening condition at emergency departments (ED). However, knowledge concerning the incidence of shock as well as etiology and mortality in the emergency setting is limited.

Objective: To study incidence of shock, distribution of shock amid each etiology, and treatment and outcomes among patients exhibiting shock at the ED of a tertiary care university hospital.

Materials and Methods: This was a retrospective cohort study. Patients presenting themselves at the ED from January 2017 to
December 2018 were screened. We included adult patients at the ED with systolic blood pressure <90 mmHg or mean arterial
pressure (MAP) <65 mmHg and >1 organ failure definition. After enrollment, patients were categorized into six etiologies of shock according to ED discharge diagnoses.

Results: A total of 113,651 adult patients attended the ED during the study period. Incidence of shock was 876 of 113,651 individuals (7.7/1,000 visits; 95% CI 7.2, 8.2). All patients had >1 organ failure, and 414 patients (47.3%) displayed at least 3 organ failures. 594 (67.8%) exhibited septic shock, 229 (26.1%) hypovolemic shock, 25 (2.9%) cardiogenic shock, 22 (2.5%) distributive shock, 5 (0.6%) obstructive shock, and 1 (0.1%) neurogenic shock. Among patients who received fluid therapy at the ED, crystalloid solutions remained the fluid of choice for patients across all groups. Norepinephrine was the most frequently applied vasopressor. Meanwhile, overall 7-day and 28-day all-cause mortality rates were 7.9% and 15.6%, respectively.

Conclusion: The incidence of shock at our ED was not uncommon (7.7/1,000 visits). Septic shock displayed the greatest prevalence, while hypovolemic shock and cardiogenic shock came in second and third, respectively.

Keywords: Shock at an emergency department, Incidence of shock, Etiology of shock