Association of appropriateness for ICU admission with resource use, organ support and long-term survival in critically ill cancer patients.

We aimed to evaluate the characteristics, resource use and outcomes of critically ill patients with cancer according to appropriateness of ICU admission. This was a retrospective cohort study of patients with cancer admitted to ICU from January 2017 to December 2018. Patients were classified as appropriate, potentially inappropriate, or inappropriate for ICU admission according to the Society of Critical Care Medicine guidelines. The primary outcome was ICU length of stay (LOS). Secondary outcomes were one-year, ICU, and hospital mortality, hospital LOS and utilization of ICU organ support. We used logistic regression and competing risk models accounting for relevant confounders in primary outcome analyses. From 6700 admitted patients, 5803 (86.6%) were classified as appropriate, 683 (10.2%) as potentially inappropriate and 214 (3.2%) as inappropriate for ICU admission. Potentially inappropriate and inappropriate ICU admissions had lower likelihood of being discharged from the ICU than patients with appropriate ICU admission (sHR 0.55, 95% CI 0.49-0.61 and sHR 0.65, 95% CI 0.53-0.81, respectively), and were associated with higher 1-year mortality (OR 6.39, 95% CI 5.60-7.29 and OR 11.12, 95% CI 8.33-14.83, respectively). Among patients with appropriate, potentially inappropriate, and inappropriate ICU admissions, ICU mortality was 4.8%, 32.6% and 35.0%, and in-hospital mortality was 12.2%, 71.6% and 81.3%, respectively (p < 0.01). Use of organ support was more common and longer among patients with potentially inappropriate ICU admission. The findings of our study suggest that inappropriateness for ICU admission among patients with cancer was associated with higher resource use in ICU and higher one-year mortality among ICU survivors.