Objective: Delirium on internal medicine and surgical wards of the general hospital is associated with several predisposing and precipitating factors as well as adverse outcomes. Whether psychosis, the symptom of delirium that may be recognized most promptly, is similarly associated with these factors and outcomes is largely unknown.
Methods: Eight thousand one hundred and thirty-nine consecutive patients undergoing coronary artery bypass grafting and/or heart valve operation were screened for preoperative predisposing factors and postoperative psychotic symptoms between January 1999 and July 2004. Data on per- and postoperative precipitating factors were collected in 4942 patients enrolled between January 2001 and July 2004. Data were examined using logistic regression to estimate odds ratios.
Results: The rate of severe psychotic symptoms was 2.1% (n=168). Higher age, renal failure, dyspnoea, heart failure, and left ventricle hypertrophy were independent preoperative predisposing factors. Peroperative hypothermia (<33 degrees C), hypoxemia, low hematocrit, renal failure, increased sodium, infection and stroke were independent precipitating factors. Psychotic symptoms were independently associated with a prolonged length of stay on the intensive care unit (odds ratio 7.8; 95% confidence interval 5.6-11), multi-organ failure or shock (3.2; 95% CI: 2.2-4.9), cardiopulmonary resuscitation (3.6; 95% CI: 2.1-6.2), and in-hospital death after surgery (2.1; 95% CI: 1.1-4.1).
Conclusions: Psychotic symptoms are independently associated with several chronic and peroperative problems (including mild hypothermia during surgery), closely resembling those for delirium (with and without psychotic symptoms). Psychotic symptoms are also independently associated with adverse outcomes. Prompt diagnostic and therapeutic intervention aimed at the underlying problem may improve outcomes.