Patterns of medical intermediate care unit use in critically ill very old patients in France

The growing population of adults aged ≥ 80 represents major challenges for critical care. Intermediate care units (IMCUs) offer a level that could bridge the gap between ICU and standard ward, but information is lacking regarding IMCU use for older critically ill patients. This study aimed to characterize critical-care trajectories involving IMCU use among older critically ill patients at a national level.

A nationwide retrospective cohort study was conducted in France, including all patients hospitalized in medical critical care in 2018. Patients were categorized as young (18-64), old (65-79), and very old adults (≥ 80). Trajectories between critical care units and general wards were visualized using Sankey diagrams. Overall survival was represented with Kaplan-Meier curves according to trajectory patterns.

Of 439,213 individuals admitted to medical critical care, 28.2% were aged ≥ 80. Among patients aged ≥ 80 admitted to an ICU, a step-up strategy (IMCU before ICU) was used in 12% of patients, and a step-down strategy (ICU followed by IMCU) in 23%. The step-up strategy was associated with high mortality in critical care (46.6%, compared to 33.9% for patients admitted directly to an ICU). Step-down patients had an extended critical care length of stay; however, those discharged from critical care via step-down strategy showed a lower cumulative mortality at one year (RR 0.86).

IMCUs play a central role in the management of very old critically ill patients. The potential benefit of IMCU care for older adults transitioning out of the ICU should be evaluated in prospective clinical trials.