Determining delayed admission to the intensive care unit for mechanically ventilated patients in the emergency department

Abstract

IntroductionThe adverse effects of delayed admission to the intensive care unit (ICU) have been recognized in previous studies. However, the definitions of delayed admission vary across studies. This study proposed a model to define ‘delayed admission’, and explored the effect of ICU waiting time on patients’ outcome.MethodsThis retrospective cohort study included nontraumatic adult patients on mechanical ventilation in the emergency department (ED), from July 2009 to June 2010. The primary outcomes measures were 21-ventilator-day mortality and prolonged hospital stays (over 30 days). Models of Cox regression and logistic regression were used for multivariate analysis. The non-delayed ICU waiting was defined as a period in which the time effect on mortality was not statistically significant in a Cox regression model. To identify a suitable cutoff point between ‘delayed’ and ‘non-delayed’ subsets from the overall data were made based on ICU waiting time and the hazard ratio of ICU waiting hour in each subset was iteratively calculated. The cutoff time was then used to evaluate the impact of delayed ICU admission on mortality and prolonged length of hospital stay.ResultsThe final analysis included 1,242 patients. The time effect on mortality emerged after 4 hours, thus we deduced ICU waiting time in the ED of >4 hours as delayed. By logistic regression analysis, delayed ICU admission affected the outcomes of 21-ventilator-day mortality and prolonged hospital stay, with an odds ratio of 1.41 (95% confidence interval, 1.05 to 1.89) and 1.56 (95% confidence interval, 1.07 to 2.27) respectively.ConclusionsFor patients on mechanical ventilation in the ED, delayed ICU admission is associated with higher probability of mortality and additional resource expenditure. A benchmark waiting time of no more than 4 hours for ICU admission is recommended.

Prolonged length of stay in the emergency department and increased risk of hospital mortality in patients with sepsis requiring ICU admission

“…Hsieh et al evaluated patients with acute respiratory failure presenting to the ED and found that patients who remained in the ED more than 1 hour before ICU admission had greater mortality than those with ED stay less than 1 hour 18. Similar findings that prolonged stay in ED was associated with worse clinical outcome have also been found in other subgroups of patients such as those requiring mechanical ventilation,19 surgery and neurologic care 20–22…”

Factors related to delayed intensive care unit admission from emergency department—A retrospective cohort study

“…Surprisingly, we did not find differences in the outcomes of 3‐month mortality or ICU LOS between the delayed and non‐delayed patients. Earlier studies have shown that each hour of delay independently associates with increased risk of ICU mortality and that delays of 4‐6 hours increase mortality . One recent study showed that in addition to increased mortality, longer stay at the ED is associated with more persistent organ dysfunction .…”

“…The delays in transferring patients from the emergency department (ED) to the intensive care unit (ICU) are known to be linked with several adverse events, including increase in hospital mortality and ICU length of stay (LOS) as well as increased requirement of mechanical ventilation during ICU stay . The factors associated with delayed ICU admission include shortage of ICU beds, organisational factors, ED overcrowding, and patient‐related factors including sepsis as admission diagnosis …”

Avoidable factors associated with pregnant and postpartum patients admitted to two intensive care units in South Africa

“…In a previous study, a time lag of >4 hours was considered as delayed admission because of its association with increased mortality. [12] In the present study, 6 hours was arbitrarily considered to represent enough time to arrange and provide an ICU bed in our setting.…”