Psychiatric complications following open heart surgery

Delirium in the postoperative cardiac patient: a review

BACKGROUND AND AIM OF REVIEW: Cardiac surgery is increasingly common and relatively safe, but there are frequent reports of neuropsychiatric sequelae occurring in the postoperative period. One of the most common neuropsychiatric presentations of cardiac surgery is delirium, also called postcardiotomy delirium (PCD). Despite the vast numbers of cardiac surgeries performed today, there is a paucity of data on risk factors and management options of PCD available to the clinician. This review aims to summarize available information, increase clinicians' awareness of PCD and suggest effective management of this illness.

METHODS

Our literature search was completed using the databases Medline and CINAHL; it was limited to human and English language studies from 1964 to the present. Search terms included "delirium," "agitation," "postoperative," "cardiac," "neuropsychiatric," "neuroleptics," "psychosis," "surgery," "treatment," "postcardiotomy," and "pharmacotherapy."

RESULTS

Our review of the literature revealed several risk factors for PCD, as well as various options for its pharmacological management.

CONCLUSIONS

A multifactorial model should be applied when considering risk stratification for and prevention of delirium postoperatively. Pharmacologically, conventional antipsychotic agents, such as haloperidol, have long been used to manage delirium. In light of haloperidol's side effects, particularly those applicable to the cardiac patient, further research is required into the role of second generation antipsychotics. These agents are common in clinical use, and may be the preferred medications.

Admission characteristics of trauma patients in whom delirium develops

BACKGROUND

The purpose of this study was to describe the admission characteristics of trauma victims that are predictive of the development of delirium during hospitalization.

METHODS

In this case-control study, data (demographics, injury type, medical histories, admission laboratory values, medications, and outcomes) were obtained from the records of 120 patients in whom delirium developed and 145 in whom it did not after admission for traumatic injury. Odds ratios were employed to identify significant predictors used in a stepwise logistic regression analysis.

RESULTS

Admission characteristics, retained after stepwise logistic regression, that were independently predictive of delirium were age more than 45 years, positive admission blood alcohol, and an elevated mean corpuscular volume. Those in whom delirium developed had longer hospital and intensive care unit lengths of stay than in whom it did not.

CONCLUSIONS

Older patients and alcoholics are at increased risk for delirum. Therapies directed at prevention have the potential to improve care and decrease lengths of stay.

Delirium after cardiac surgery: a critical review

Numerous articles have been published investigating the incidence of and risk factors for delirium after cardiac surgery. Smith and Dimsdale reviewed the literature on postcardiotomy delirium in 1987 using a meta-analysis of 44 research studies. However, doubts about their methods and results caused the authors to re-examine the literature using these 44 references as well as computerized literature searches to gather research and review papers from medical journals. Delirium after cardiac surgery appeared to be ill-defined in most of these studies. The methods and instruments used to assess delirium proved to be very different, and the patient samples were rather heterogeneous. Therefore, in most cases, the results are not comparable. Only a small number of the studies that were examined fit the criteria for statistical meta-analysis. On the basis of our analysis, a tentative conclusion may be drawn that the incidence of postcardiotomy delirium has declined slightly and that no strong risk factors have yet been identified.

[The Hamburg Rating Scale for psychiatric disorders following heart operations (HRPD)]

A brief psychiatric inventory has been developed from the AMP/AMDP system for the assessment and classification of psychic disturbances after open heart surgery in a random sample of 99 patients operated upon. By means of item analysis in accordance with classic test theory, a list of 36 symptoms (items) was selected. Factor analysis of this brief inventory resulted in eight factors: disorientation, impaired concentration and thinking, paranoid-hallucinatory symptoms, anxiety, sullen inadequacy (restraint depression), hostility, loss of control, giving up. By cluster analysis the sample was divided into six subgroups: "unnoticeable", "rather unnoticeable", "slight psycho-organic symptoms with affective-emotional disturbances", "severe psycho-organic symptoms with loss of control", "hostility with paranoid and hallucinatory and psycho-organic symptoms", "delirious symptoms". Some results agree well with the descriptions of syndromes given by other AMP/AMDP reports. Other divergent results probably reflect the particular situation of the patients after open heart surgery.

Psychopatho-ophthalmology, gnostic disorders, and psychosis in cardiac surgery. Visual disturbances after open heart surgery

The visual disturbances of 45 patients following open heart surgery could be divided into disturbances of (1) visual acuity, (2) visual accuracy, and (3) visual reality testing. The non-hallucinatory phenomena consisted mainly of loss of colour vision, metamorphopsias, visual gnostic disorders and cortical blindness. The hallucinatory phenomena could be divided into the delirium type of hallucinations with clouding of consciousness and the spectator type of hallucinations with a clear sensorium. The causes of the visual symptomatology and cardiac psychoses are seen in microembolization and/or ischemic hypoxia. The basal ganglia and the occipital lobe are areas of predilection for embolic and hypoxic changes. Identical psychoses also occur in cerebral malaria and polycythemia vera which show the same embolic and anoxic neuropathological changes of vascular occlusion as do many patients who die following open heart surgery with extracorporal circulation.

The psychodynamic impact of coronary bypass surgery

Twenty-one individuals underwent extensive psychological evaluation before, and four months after, coronary bypass surgery, that examined: defensive mechanisms; fantasies and distortions; subjective meaning of the procedure; and transference and projections. Patients showed a significant improvement in their physical condition and indicated vigorous psychodynamic activity. Both before and after surgery many patients: a) used denial; b) misconceived the procedure; c) developed a subjective explanation of etiology; d) mourned; and e) revered their surgeon. Following surgery, many patients: a) rationalized their decision; b) reviewed their life and changed priorities (valuing human closeness, devaluing work); and c) recognized their mortality (engendering a renewed interest in life and/or rage).

Ego-supportive care in open-heart surgery

Open heart surgery has been shown to have a rate of occurrence of postoperative psychopathological phenomena (9 percent-57 percent) many times greater than that of general surgery (1/1500). These phenomena result from an interplay of organic, environmental, psychological, and social factors which act on the integrative and coping capacity of the ego.

Treatment is accomplished through support of the ego by: 1) establishment of a relationship, 2) reassurance, 3) environmental support, 4) consultative relationships with staff, 5) ventilation of feelings, 6) medical measures in support of somatic function, and 7) anti-anxiety drugs. Such supportive measures are usually effective in bringing about a rapid remission of these psychopathological phenomena.