Hallucinations after Cardiac Surgery: A Prospective Observational Study

Area of Science:

• Cardiology
• Psychiatry
• Neuroscience

Background:

• Hallucinations following cardiac surgery are a significant concern but poorly understood.
• Prevalence, characteristics, and risk factors for postoperative hallucinations remain unclear.
• The relationship between hallucinations and delirium in this patient group requires further investigation.

Purpose of the Study:

• To determine the prevalence and phenomenology of hallucinations in patients after cardiac surgery.
• To investigate the association between postoperative hallucinations and delirium.
• To identify potential risk factors for hallucinations post-cardiac surgery.

Main Methods:

• Utilized the Questionnaire for Psychotic Experiences to identify hallucinations in cardiac surgery patients and cardiology outpatients.
• Assessed postoperative delirium using validated instruments.
• Employed logistic regression to analyze risk factors and the association between hallucinations and delirium.

Main Results:

• 21.9% of cardiac surgery patients (44/201) experienced hallucinations within four days post-surgery, significantly higher than cardiology outpatients (4.1%, 4/99).
• Visual hallucinations were the predominant type in cardiac surgery patients.
• Patients with hallucinations were more likely to have delirium (22.7% vs. 10.2%), but most hallucinating patients (77.3%) did not develop delirium.

Conclusions:

• Hallucinations are more frequent after cardiac surgery compared to general cardiology outpatients.
• Visual hallucinations are the most common type experienced post-cardiac surgery.
• While associated with delirium, hallucinations post-cardiac surgery often occur independently of delirium.