The Impact of Postoperative Mechanical Ventilation Duration on Visual and Auditory Hallucinations After Cardiac Surgery: Insights from the VAACS Study

To determine whether postoperative mechanical ventilation duration is associated with the risk and timing of visual and auditory hallucinations after adult cardiac surgery.

Prospective multicenter cohort study.

Ten major cardiac surgery centers in the West Bank, Palestine.

A total of 1,332 adults undergoing coronary artery bypass grafting or valve surgery, stratified by postoperative ventilation duration: ≤6 hours or >6 hours.

No experimental intervention was performed; patients were grouped by early versus delayed postoperative extubation.

Visual and auditory hallucinations were assessed during the first 7 postoperative days using the Questionnaire for Psychotic Experiences. Cox regression and restricted mean survival time analyses evaluated associations between ventilation duration and hallucination outcomes. Delayed extubation (>6 hours) was associated with lower overall adjusted risk of visual hallucinations (adjusted hazard ratio, 0.70; 95% CI, 0.62–0.80; p < 0.001) and auditory hallucinations (adjusted hazard ratio, 0.49; 95% CI, 0.31–0.77; p = 0.002). However, time-varying analysis showed increased immediate postoperative hazard in the delayed-extubation group, with risk declining rapidly over time. Restricted mean survival time analysis showed auditory hallucinations occurred approximately 0.24 days earlier in patients with delayed extubation (p < 0.001). Preoperative white blood cell count was the most consistent predictor.

Delayed postoperative extubation was associated with lower overall 7-day hallucination risk but higher immediate postoperative vulnerability, suggesting that the early post-extubation period may represent a critical window for targeted monitoring and preventive neuropsychiatric care after cardiac surgery.