Journal Article Annotations
2018, 4th Quarter
Annotations by O. Joseph (“Joe”) Bienvenu, MD, PhD
Type of study: Systematic review
The finding: Kok et al systematically investigated the effect of benzodiazepines on common in-ICU and post-ICU neuropsychiatric phenomena, including delirium, long-term cognitive impairment, anxiety, depression, and posttraumatic stress disorder (PTSD) symptoms. By far, the most studied outcome was in-ICU delirium. Kok et al report that, in most of the studies that examined the issue, benzodiazepines appeared causally related to delirium. In addition, the more rigorous studies in the review tended to confirm this result. Fewer studies examined the long-term post-ICU outcomes cognitive impairment, anxiety, depression, and PTSD symptoms. Nevertheless, results suggested that higher doses of benzodiazepines were associated with worse long-term cognitive outcomes, as well as more anxiety, depression, and PTSD symptoms.
Strength and weaknesses: Strengths include the systematic searches of relevant databases, as well as evaluation of methodologic quality of included studies. A weakness of the literature reviewed is that most studies that evaluated longer-term (post-ICU) outcomes were not randomized.
Relevance: Clinicians should administer as little benzodiazepine or other GABA-enhancing sedative medication as possible, in order to preserve brain functioning, shorten the duration of mechanical ventilation, allow in-ICU physical rehabilitation, and allow patients to cognitively and emotionally process what is occurring within and around them more completely.
Type of study: Prospective cohort study
The finding: In this UK-wide multicenter outcome study, almost 5,000 critical illness survivors returned postal questionnaires that included the Hospital Anxiety and Depression Scale and the Civilian version of the PTSD Checklist. Of these 46%, 40%, and 22% had clinically significant symptoms of anxiety, depression, and PTSD at 3 and/or 12 months after discharge. Patients with clinically significant depressive symptoms were 47% more likely to die during the first 2 years after ICU.
Strength and weaknesses: This was a very large study, involving 26 ICUs; however, only 38% of survivors returned the postal questionnaires, potentially limiting generalizability.
Relevance: This is the first study of critical illness survivors to assess the effect of psychiatric morbidity on survival. Clinically significant depressive symptoms after critical illness either add risk for death through poor self-care, etc., or are a marker of risk for death.