Application of the Italian version of the Intensive Care Unit Memory tool in the clinical setting

The aims of the present study were to assess patients' memories of their stay in the intensive care unit (ICU) over time, using the Italian version of the ICU Memory (ICUM) tool, and to examine the relationship between memory and duration of ICU stay and infection.

Adult patients consecutively admitted to a four-bed ICU of a university hospital, whose stay in the ICU was at least 3 days, were prospectively studied. The ICUM tool was administered twice: face to face 1 week after ICU discharge to 93 patients (successfully in 87); and by phone after 3 months to 67 patients. Stability of memories over time was analyzed using Kappa statistics.

Delusional memories appeared to be the most persistent recollections over time (minimum kappa value = 0.68), followed by feelings (kappa value > 0.7 in three out of six memories) and factual memories (kappa value > 0.7 in three out of 11 memories). The patients without a clear memory of their stay in the ICU reported a greater number of delusional memories than did those with a clear memory. Of patients without infection 35% had one or two delusional memories, and 60% of patients with infection had one to four delusional memories (P = 0.029).

The ICUM tool is of value in a setting and language different from those in which it was created and used. Delusional memories are the most stable recollections, and are frequently associated both with lack of clear memory of ICU experience and with presence of infection during ICU stay.