Outcome of Cancer Patients with an Unplanned Intensive Care Unit Admission: Predictors of Mortality and Long-term Survival

Background: Understanding the characteristics and outcomes of cancer patients with unplanned ICU admission is imperative for therapeutic decisions and prognostication purposes. Objective: To describe the clinical characteristics of patients with hematological and non-hematological malignancies (NHM) who require unplanned ICU admission and to determine the predictors of mortality and long-term survival. Methods: This retrospective study included all patients with cancer who had an unplanned ICU admission between 2011 and 2016 at a tertiary hospital in Saudi Arabia. The following variables were collected: age, gender, ICU length of stay (LOS), APACHE II score, type of malignancy, febrile neutropenia, source and time of admission, and need for mechanical ventilation (MV), renal replacement therapy (RRT), and treatment with vasopressors (VP). Predictors of mortality and survival rates at 28 days and 3, 6, and 12 months were calculated. Results: The study included 410 cancer patients with 466 unplanned ICU admissions. Of these, 52% had NHM. The average LOS in the ICU was 9.6 days and the mean APACHE score was 21.9. MV was needed in 73% of the patients, RRT in 15%, and VP in 24%, while febrile neutropenia was present in 24%. There were statistically significant differences between survivors and non-survivors in the APACHE II score (17.7 ± 8.0 vs. 25.6 ± 9.2), MV use (52% vs. 92%), need for RRT (6% vs. 23%), VP use (42% vs. 85%), and presence of febrile neutropenia (18% vs. 30%). The predictors of mortality were need for MV (OR = 4.97), VP (OR = 3.43), RRT (OR = 3.31), and APACHE II score (OR = 1.10). Survival rates at 28 days, 3, 6, and 12 months were 52%, 28%, 22%, and 15%, respectively. Conclusion: The survival rate of cancer patients with an unplanned admission to the ICU remains low. Predictors of mortality include need for MV, RRT, and VP and presence of febrile neutropenia. About 85% of cancer patients died within 1 year after ICU admission.