Psychological distress and delusional memories after critical care: a literature review

Background: A considerable number of intensive care unit (ICU) survivors report delusional memories, which refer to dreams, nightmares, paranoid delusions and hallucinations experienced in the ICU. These memories often have a strong vividness, long duration and high emotional impact. Aim: The aim of this review was to investigate and synthesize published literature about psychological distress associated with delusional memories of adult ICU survivors. Methods: Using key terms, a search was conducted in major health care electronic databases [Cumulative Index for Nursing and Allied Health Literature (CINAHL), PubMed, Web of Science and PsycInfo] focusing on articles published between 1990 and 2009 in English-language journals. Findings: Ten articles met the inclusion criteria. Recall of delusional memories at various intervals after ICU discharge was associated with post-traumatic stress disorder (PTSD)-related symptoms in many studies, while associations with other aspects of psychological distress, mainly feelings of fear, anxiety and depression, were also reported. Recent studies did not seem to confirm the protective role of factual memories. Conclusions: The findings support the association between delusional memories and PTSD-related symptoms, but further research is needed to confirm their association with other psychological disorders. Development of a safety sense in the ICU can protect patients against the emotional impact of both delusional and stressful factual ICU memories. Appropriate follow-up of high-risk patients could improve their long-term psychological recovery.