Date Published: January 24, 2019
Publisher: Public Library of Science
Author(s): Byeong-Ho Jeong, Soo Jin Na, Dae-Sang Lee, Chi Ryang Chung, Gee Young Suh, Kyeongman Jeon, Shane Patman.
Intensive care unit (ICU) readmission is generally associated with increased hospital stays and increased mortality. However, there are limited data on ICU readmission in critically ill cancer patients.
We conducted a retrospective cohort study based on the prospective registry of all critically ill cancer patients admitted to the oncology medical ICU between January 2012 and December 2013. After excluding patients who were discharged to another hospital or decided to end-of-life care, we divided the enrolled patients into four groups according to the time period from ICU discharge to unexpected events (ICU readmission or ward death) as follows: no (without ICU readmission or death, n = 456), early (within 2 days, n = 42), intermediate (between 2 and 7 days, n = 64), and late event groups (after 7 days of index ICU discharge, n = 129). The independent risk factors associated with ICU readmission or unexpected death after ICU discharge were also analyzed using multinomial logistic regression model.
There were no differences in the reasons for ICU readmission across the groups. ICU mortality did not differ among the groups, but hospital mortality was significantly higher in the late event group than in the early event group. Mechanical ventilation during ICU stay, tachycardia, decreased mental status, and thrombocytopenia on the day of index ICU discharge increased the risk of early ICU readmission or unexpected ward death, while admission through the emergency room and sepsis and respiratory failure as the reasons for index ICU admission were associated with increased risk of late readmission or unexpected ward death. Interestingly, recent chemotherapy within 4 weeks before index ICU admission was inversely associated with the risk of late readmission or unexpected ward death.
In critically ill cancer patients, patient characteristics predicting ICU readmission or unexpected ward death were different according to the time period between index ICU discharge and the events.
The development of diagnostic and therapeutic modalities of cancer and improved clinical outcomes have caused an increase in the inflow of critically ill cancer patients to the intensive care unit (ICU) . Despite recent studies suggesting the benefits of intensive care in cancer patients, it is also true that they still have worse clinical outcomes than patients without cancer [2,3]. Efforts have been made to identify the risk factors for ICU admission and mortality in cancer patients to improve their outcomes and to reduce the economic burden; however, there is limited data on unplanned ICU readmission and unexpected ward death after index ICU discharge in cancer patients, which is known to be associated with increased in-hospital mortality, length of hospital stay, and medical cost [4,5].
We conducted a retrospective cohort study based on the prospective registry of all critically ill patients with active cancer, defined as diagnosis of cancer, and any treatment for cancer within the previous six-month period or recurrent or metastatic cancer documented by medical record, admitted to the oncology medical ICU of the Samsung Comprehensive Cancer Center of Samsung Medical Center (a 1,979-bed tertiary referral hospital in Seoul, South Korea) between January 2012 and December 2013. The ICU has 14 beds and provides care for approximately 350 critically ill cancer patients per year . The institutional review board of Samsung Medical Center approved this study and waived the requirement for informed consent because of the observational nature of the study.
Patient distribution after being discharged alive from the intensive care unit (ICU) is shown in Fig 1.
In this study, we investigated the epidemiology, characteristics including disease-specific and treatment-related variables, and clinical outcomes of patients who experienced ICU readmission or death in the ward based on the time interval between discharge and readmission or unexpected ward death and compared them with those of patients who were discharged from the hospital alive without ICU readmission during their same hospitalization.
In summary, about one-third of critically ill cancer patients were readmitted to the ICU or died on the ward after being discharged alive from the index ICU admission. Risk factors associated with ICU readmission and mortality were different across the time intervals between discharge and events. Therefore, it is necessary to carefully assess residual organ dysfunction at ICU discharge as well as the treatment of underlying disease after ICU discharge in order to reduce ICU readmission and hospital mortality in critically ill cancer patients.