Abstract
BACKGROUND: Critical care covers multiple disciplines. However, the causes of critical illness in the ICU, particularly the most common causes, remain unclear. We aimed to investigate the incidence and the most common causes of critical illness and the corresponding early mortality rates in ICU patients. METHODS: A retrospective cohort study was performed to examine critically ill patients (aged over 15 years) in the general ICU in Shuyang County in northern China (1/2014-12/2015). The incidences and causes of critical illnesses and their corresponding early mortality rates in the ICU were determined by an expert panel. RESULTS: During the 2-year study period, 1,211,138 person-years (PY) and 1645 critically ill patients (mean age, 61.8 years) were documented. The median Glasgow Coma Scale (GCS) score was 6 (range, 3-15). The mean acute physiology and chronic health evaluation II (APACHE II) score was 21.2 ± 6.8. The median length of the ICU stay was 4 days (range, 1-29 days). The most common causes of critical illness in the ICU were spontaneous intracerebral hemorrhage (SICH) (26%, 17.6/100,000 PY) and traumatic brain injury (TBI) (16.8%, 11.4/100,000 PY). During the first 7 days in the ICU, SICH was the most common cause of death (42.2%, 7.4/10,000 PY), followed by TBI (36.6%, 4.2/100,000 PY). Based on a logistic analysis, older patients had a significantly higher risk of death from TBI (risk ratio [RR], 1.7; 95% CI, 1.034-2.635), heart failure/cardiovascular crisis (RR, 0.2; 95% CI, 0.083-0.484), cerebral infarction (RR, 0.15; 95% CI, 0.050-0.486), or respiratory failure (RR, 0.35; 95% CI, 0.185-0.784) than younger patients. However, the risk of death from SICH in the two groups was similar. CONCLUSIONS: The most common causes of critical illness in the ICU were SICH and TBI, and both critical illnesses showed a higher risk of death during the first 7 days in the ICU.