Preventing post-traumatic stress disorder (PTSD) after a critical illness

The Bottom Line

  • People who suffer and survive a critical illness are at increased risk of developing post traumatic stress disorder (PTSD).
  • People with mental health issues, scary memories of their medical emergency, or who are sedated with drugs which can cause frightening delusions or hallucinations are even more at risk.
  • ICU diaries completed by hospital staff and/or family members may help prevent or reduce PTSD symptoms.

If you’ve ever had a medical emergency and had to spend time in the hospital’s ICU (intensive care unit) you know how scary it can be. The beeping monitors, the barrage of questions from medical staff, the drug-induced wooziness and sleep deprivation, not to mention pain, possibly invasive treatments like a breathing tube and almost certainly concern for your survival – all of this can cause anyone to feel overwhelmed.

The term ‘post-traumatic stress disorder’ or PTSD, was originally associated with war veterans. But this mental health problem can affect anyone exposed to a frightening, traumatic and/or life threatening episode (1) and a critical illness certainly falls into that category. In fact at least 10% – and as many as 60% – of patients discharged from an ICU suffer PTSD at some point (2;3).

Symptoms can appear months after being hospitalized and may include recurring flashbacks, nightmares and a tendency to avoid situations that might bring back memories of the event (1). People with PTSD are often anxious and have trouble concentrating, sleeping, interacting with others and enjoying activities – all of which can severely affect their quality of life (1;4).

To learn more about the relationship between critical illness and PTSD, including risk factors and potential treatments, a recent high quality systematic review and meta analysis was conducted (5). The 40 included studies measured PTSD symptoms among adults who had survived a critical illness. Symptoms were measured at least a month after patients had been discharged from the ICU.

What the research tells us

While there is no sure way to predict who might develop PTSD (age, gender and the severity of the illness did not appear to increase risk) a few ’red flags’ emerged from this review.

For example, people who already have mental health issues such as depression or anxiety and patients who have scary memories after being in the ICU are at higher risk of developing PTSD after a critical illness (5). Being under heavy sedation is another factor (5). Patients who were sedated with benzodiazepines – a drug which can cause delirium and intensify delusions and hallucinations (6) – had more PTSD symptoms.

Two of the studies focused on treatment involving the use of “ICU diaries” (7;8). Medical staff and/or family members use notebooks to write daily messages about the person’s status and any other relevant information, often accompanied by photos. The diaries are given to patients after they leave the hospital to help them understand what really happened (as opposed to what they dreamed/hallucinated) during their time in the ICU (9). Both of these studies, including a randomized controlled trial involving 352 people (7), found that the diaries appeared to reduce PTSD symptoms by a small but significant amount (7;8).

So far, ICU diaries have been used primarily in Europe but plans are underway to introduce them to North American hospitals and measure their effectiveness (10) while continuing to explore other possible prevention and treatment options so that survivors of a critical illness may enjoy the best possible quality of life.

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  1. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington, VA: American Psychiatric Publishing, 2013; 271–280.
  2. Davydow DS, Gifford JM, Desai SV et al. Posttraumatic stress disorder in general intensive care unit survivors: A systematic review. Gen Hosp Psychiatry. 2008; 30:421-434.
  3. Wade D, Hardy R, Howell D et al. Identifying clinical and acute psychological risk factors for PTSD after critical care: A systematic review. Minerva Anestesiol. 2013; 79:944-963.
  4. Canadian Mental Health Association: Post-traumatic stress disorder [Internet] 2015. [cited Mar 2016]. Available from:
  5. Parker AM, Sricharoenchai T, Raparla S et al. Posttraumatic stress disorder in critical illness survivors: A meta-analysis. Crit Care Med. 2015; 43:1121-1129.
  6. Clegg A, Young JB. Which medications to avoid in people at risk of delirium: a systematic review. Age Aging. 2011; 40:23-29.
  7. Jones C, Bäckman C, Capuzzo M, et al; RACHEL group: Intensive care diaries reduce new onset post traumatic stress disorder following critical illness: A randomised, controlled trial. Crit Care 2010;14:R168
  8. Garrouste-Orgeas M, Coquet I, Périer A, et al: Impact of an intensive care unit diary on psychological distress in patients and relatives. Crit Care Med 2012; 40:2033–2040
  9. International ICU Diary Network [Internet] 2012. [cited Mar 2016]. Available from:
  10. Johns Hopkins Medicine: PTSD common in ICU survivors [Internet] April 2015. [cited Mar 2016]. Available from:

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