Deliberate drug poisoning with slight symptoms on admission: are there predictive factors for intensive care unit referral? A three-year retrospective study.

Deliberate drug poisoning leads to 1% of emergency department (ED) admissions. Even if most patients do not exhibit any significant complication, 5% need to be referred to an intensive care unit (ICU). Emergency physicians should distinguish between low- and high-acuity poisoned patients at an early stage to avoid excess morbidity. Our aim was to identify ICU transfer factors in deliberately self-poisoned patients without life-threatening symptoms on admission. We performed a 3-year retrospective observational study in a university hospital. Patients over 18 years of age with a diagnosis of deliberate drug poisoning were included. Clinical and toxicological data were analysed with univariate tests between groups (ED stay versus ICU transfer). Factors associated with ICU admission were then included in a logistic regression analysis. Two thousand five hundred and sixty-five patients were included. 63.2% were women, and median age was 40 (28-49). 142 patients (5.5%) were transferred to ICU. Cardiac drugs [adjusted OR (aOR) = 19.81; 95% confidence interval (95% CI): 7.93-49.50], neuroleptics (aOR = 2.78; 95% CI: 1.55-4.97) and meprobamate (aOR = 2.71; 95% CI: 1.27-5.81) ingestions were significantly linked to ICU admission. A presumed toxic dose ingestion (aOR = 2.27; 95% CI: 1.28-4.02), number of ingested tablets (aOR = 1.01; 95% CI: 1.01-1.02 for each tablet) and delay between ingestion and ED arrival <2 hr (aOR = 2.85; 95%CI: 1.62-5.03) were also factors for ICU referral. The Glasgow Coma Scale was the only clinical feature associated with ICU admission (aOR = 1.57; 95% CI: 1.44-1.70 for each point loss). These results suggest that emergency physicians should pay particular attention to toxicological data on ED admission to distinguish between low- and high-acuity self-poisoned patients.