Outcomes and Costs of Patients Admitted to the Intensive Care Unit Due to Accidental or Intentional Poisoning

Abstract

Introduction: Acute poisoning represents a major cause of morbidity and mortality, and many of these patients are admitted to the intensive care unit (ICU). However, little is known regarding ICU costs of acute poisoning. Methods: This was a retrospective matched database analysis of patients admitted to the ICU with acute poisoning from 2011 to 2014. It was performed in 2 ICUs within a single tertiary care hospital system. All patient information, outcomes, and costs were stored in the hospital data warehouse. Control patients were defined as randomly selected age-, sex-, severity index-, and comorbidity index-matched nonpoisoned ICU patients (1:4 matching ratio). Results: A total of 8452 critically ill patients were admitted during the study period, of whom 277 had a diagnosis of acute poisoning. The mean age was 44.5 years, and the most common xenobiotics implicated were sedative hypnotics (20.2%), antidepressants (15.2%), and opioids (10.5%). Of these, 73.6% of poisonings were deemed intentional. In-hospital mortality of poisoned patients was 5.1%, compared to 11.1% for control patients (P <.01). The median ICU length of stay (LOS) for poisoned patients was 3.0 days, compared with 4.0 days for control patients (P <.01). The mean total cost for poisoned patients was CAD$18 958. Control patients had a significantly higher mean total cost of CAD$60 628 (P <.01). The xenobiotics associated with the highest costs were acetaminophen (CAD$18 585), toxic alcohols (CAD$16 771), and opioids (CAD$12 967). Conclusions: In our cohort, we confirmed the long-held belief that patients admitted to the ICU with a primary diagnosis of poisoning have a lower mortality rate, ICU LOS, and overall cost per ICU admission than nonpoisoned patients. However, poisoned patients still accrue significant daily costs, with the highest costs attributed to xenobiotics with known antidotes, such as acetaminophen, toxic alcohols, and opioids.