Eleven years after Winterbottom's report of a case of awareness during anesthesia,1 Meyer and Blacher2 reported that patients who awakened during surgery may develop “traumatic neurosis,” a term that preceded the introduction of posttraumatic stress disorder (PTSD) as a diagnosis by the American Psychiatric Association.3,4 There followed some case reports and a few studies whose numbers are in the single digits, which brings us to the article published in this issue of Anesthesia & Analgesia by Leslie et al.5 These investigators studied 7 awareness patients and 25 controls from a previous study who did not experience awareness.6 The median duration between the surgery and their investigation was 4.7 years. They used the Clinician-Administered PTSD Scale7 to evaluate PTSD symptom frequency and severity. The authors found that 5 awareness patients and 3 control patients met the diagnostic threshold for PTSD. Their conclusion was that PTSD symptoms were common and persistent in the sample of awareness patients. It is acknowledged that the longer these debilitating symptoms persist, the more likely it is that treatment will fail.8 The authors also found that 3 of the 5 awareness patients did not report psychiatric sequelae within 30 days of the surgery, although they reported that symptoms were initially present when they were interviewed several years later. Moreover, the patients did not accept psychiatric counseling, which was offered to them once their awareness was diagnosed. Therefore, the authors sensibly suggested that awareness patients should also be advised to seek counseling whenever the symptoms may come to the surface regardless of how long it takes. The other important observation by the authors was the finding that 3 of the control patients developed PTSD, a reminder that this condition has been reported after a variety of diseases and procedures, including surgical operations,9 and will be commented on separately in another editorial.
PTSD develops after a traumatic event, in this case awareness during anesthesia, which elicits a reaction of intense fear, helplessness, or horror, and is characterized by 3 symptom complexes4: (1) reexperiencing, e.g., recalling fragments of the awareness episodes in nightmares and flashbacks, (2) avoidance, e.g., avoiding hospitals, physicians, and going to sleep, and (3) physiologic hyperarousal, e.g., anxiety, irritability, and chronic fear. Its prevalence is unknown, but if we assume an incidence of awareness as 0.1% to 0.2% in general surgical cases and an incidence of late psychological symptoms of about 26% of awareness cases,5 one may expect a PTSD incidence of about 0.03% to 0.05%.
The “gold standard” for diagnosing PTSD is a structured clinical interview to evaluate predefined criteria (Diagnostic and Statistical Manual of Mental Disorders, 4th ed.)4 by a psychiatrist or clinical psychologist experienced in the assessment and treatment of PTSD. The Clinician-Administered PTSD Scale7 has been developed and validated to be used by experienced clinicians and thoroughly trained paraprofessionals. It has the advantage of providing a continuous severity measure for individual symptoms.
Symptoms such as intrusive recollections, avoidance, and hyperarousal impair the patients' quality of life and impose restrictions that frequently are more severe than the primary disease for which surgery was performed. These emotional problems frequently are also more difficult to treat than the physical problems of the primary disease. The impairment in mental health may in turn affect physical health through the immune system, as well as other factors such as poor compliance with medications, poor self-care, and unhealthy lifestyles.9 In addition to the potential for increased morbidity and mortality and use of health care resources, patients remain out of work for long periods of time and when they return to work, they have difficulties.10 Some of these patients are also likely to resort to malpractice litigation.11
It is therefore important to identify the risk factors that predispose patients to this poor outcome to provide them with intense psychological support at an early stage and to prevent the development of the full PTSD if these factors are modifiable. The literature suggests that female patients may be more likely to experience awareness12 and to develop PTSD.13 Children exposed to traumatic events can develop PTSD, although a recent study of 11 children who experienced awareness found that none developed psychological sequelae.14 The general PTSD literature suggests that patients with certain personality traits or temperaments, such as patients with neurosis or low agreeableness, and patients who complain more from somatic problems, are socially dysfunctional, and have low social support, may be more prone to develop PTSD. Patients with previous mental health difficulties and ongoing severe comorbidities may also be more prone to develop PTSD.15
Complaints immediately after awareness of paralysis or inability to move, and feelings such as helplessness, anxiety, and panic, were found to be significantly related to the persistence of late psychological symptoms.16–18 Patients might then resort to passive coping or dissociation because of their inability to terminate the terrifying experience. Research has shown that when the patient's internal resources are depleted, external support needs to be mobilized to compensate for their helplessness.16 Denial of the authenticity of the patient's experience of awareness may predispose them to develop PTSD. In addition, severe physical postoperative complications related to the surgery can have additive effects and impair the patient's ability to cope. Of course, prevention should ultimately be directed at the cause of the trauma, namely awareness. In addition, if awareness occurs, patients should be offered early psychiatric counseling.
The current anesthesia practice of visiting patients only once in the first few days after surgery will miss some cases of awareness. It has therefore been proposed that for every patient who develops psychiatric problems postoperatively, an awareness-induced PTSD should be considered in the differential diagnosis.19
In conclusion, PTSD is a debilitating disorder that can arise in a fraction of patients after awareness during general anesthesia. It has the potential to increase morbidity and mortality, increase the use of health care resources, and lead to a nonproductive, dysfunctional life. It is important to identify those at risk and to provide early treatment to avoid continued disability of the patient. Future studies should be directed at obtaining a more precise estimate of the prevalence of PTSD after awareness and methods for its prevention and treatment. It is possible that some of these latter issues may be easier to study in patients treated in intensive care units, where the sample size would be immensely larger, and the incidence of PTSD may be as high as that after awareness during anesthesia.
1.Winterbottom EH. Insufficient anaesthesia. Br Med J 1950;1:247–8
2.Meyer BC, Blacher RS. A traumatic neurotic reaction induced by succinylcholine chloride. NY State J Med 1961;61:1255–61
3.American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 3rd ed. Washington, DC: American Psychiatric Association, 1987
4.American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 4th ed. Washington, DC: American Psychiatric Association, 1994
5.Leslie K, Chan MTV, Myles PS, Forbes A, McCulloch TJ. Posttraumatic stress disorder in aware patients from the B-Aware trial. Anesth Analg 2010;110:823–8
6.Myles PS, Leslie K, McNeil J, Forbes A, Chan MT. Bispectral index monitoring to prevent awareness during anaesthesia: the B-Aware randomised controlled trial. Lancet 2004;363:1757–63
7.Blake D, Weathers F, Nagy L, Kaloupek D, Gusman F, Charney D, Keane T. The development of a clinician-administered PTSD scale. J Trauma Stress 1995;8:75–90
8.Kessler RC, Sonnega A, Bromet E, Hughes M, Nelson CB. Posttraumatic stress disorder in the national comorbidity survey. Arch Gen Psychiatry 1995;52:1048–60
9.Tedstone JE, Tarrier N. Posttraumatic stress disorder following medical illness and treatment. Clin Psychol Rev 2003;23:409–48
10.Nyberg E, Stieglitz RD, Frommberger U, Berger M. [Psychological disorders after severe occupational accidents]. Versicherungsmedizin 2003;55:76–81
11.Kent CD, Domino KB. Awareness: practice, standards, and the law. Best Prac Res Clin Anaesthesiol 2007;21:369–83
12.Ghoneim MM. Incidence and risk factors for awareness during anaesthesia. Best Prac Res Clin Anaesthesiol 2007;21:327–43
13.Breslau N, Davis GC, Andreski P, Peterson EL, Schultz LR. Sex differences in post-traumatic stress disorder. Arch Gen Psychiatry 1997;54:1044–8
14.Lopez U, Habre W, van der linden M, Iselin-Chaves IA. Intra-operative awareness in children and post-traumatic stress disorder. Anaesthesia 2008;63:474–81
15.Chung MC, Berger Z, Rudd H. Comorbidity and personality traits in patients with different levels of posttraumatic stress disorder following myocardial infarction. Psychiatry Res 2007;152:243–52
16.Osterman JE, Hopper J, Hernan WJ, Keane TM, van der Kolk BA. Awareness under anesthesia and the development of posttraumatic stress disorder. Gen Hosp Psychiatry 2001;23:198–204
17.Samuelsson R, Brudin L, Sandin RH. Late psychological symptoms after awareness among consecutively included surgical patients. Anesthesiology 2007;106:26–32
18.Ghoneim MM, Block RI, Haffarnan M, Mathews M. Awareness during anesthesia: risk factors, causes and sequelae: a review of reported cases in the literature. Anesth Analg 2009;108:527–35
19.Osterman JE, van der Kolk BA. Awareness during anesthesia and posttraumatic stress disorder. Gen Hosp Psychiatry 1998;20:274–81