ICU admission delays: Impact on length of stay and long-term outcomes

Abstract

Delays in intensive care unit (ICU) admissions are prevalent in overcrowded hospitals and can adversely affect patient outcomes. However, the extent of this impact, particularly beyond short-term mortality, remains unclear. We hypothesized that ICU admission delays exceeding 6 hours after consultation would independently increase 90-day mortality and prolong ICU length of stay. We conducted a retrospective analysis of data from 273 adult patients admitted to the ICU of a tertiary university hospital between January and December 2019. Patients were stratified into two groups: early admission (≤6 hours) and delayed admission (>6 hours). Multivariate Cox regression was employed to identify independent predictors of mortality. Delayed ICU admission was observed in 72.8% of patients. Although delayed admission was not independently associated with increased mortality in the multivariate analysis (HR: 0.88; 95% CI: 0.61–1.27), it was significantly correlated with prolonged ICU length of stay and higher 90-day mortality in the univariate analysis (p = 0.039), with no significant difference in vasopressor-free days (p = 0.809). In our assessment of independent mortality predictors, we found that patients with higher APACHE-II and Charlson scores experienced longer delays in ICU transfer. Additionally, respiratory and circulatory failure at admission were independently associated with increased mortality (HR: 2.17; 95% CI: 1.51–3.12). While early ICU admission did not independently predict mortality, it was linked to extended ICU stays, an increased treatment burden, and adverse long-term outcomes. These findings underscore the necessity of refining triage processes and evaluating baseline patient severity when interpreting the impact of ICU admission timing on outcomes.