Delirium Screening in Cardiac Surgery (DESCARD): a useful tool for nonpsychiatrists

The aim of the study was to set up and validate a predictive scoring system for nonpsychiatrists to facilitate screening of postoperative delirium in cardiac surgery patients.

The project was conducted as a cohort study in 5781 subjects. More than 100 pre- and perioperative somatic variables were collected to build up an algorithm. Delirium was diagnosed using Diagnostic and Statistical Manual of Mental Disorders 4th edition. The patient cohort was divided into a training and validation set to perform cross-validation. Scoring systems (Delirium Screening in Cardiac Surgery [DESCARD] tool) were developed for the set of sole preoperative and all perioperative risk factors.

Delirium was found in 236 patients (4.1%). The preoperative model comprised age, weight, total protein concentration, arterial hypertension, mode of surgery (elective/urgent/emergent), preoperative fasting glucose, and form of diabetes treatment (diet/oral agents/insulin). Taking into account all the perioperative variables, the scoring system included postoperative cerebral ischemia and the need for red blood cell transfusion, and arterial hypertension and mode of surgery were excluded. Both pre- and perioperative tools had an excellent overall diagnostic accuracy (area under receiver operator characteristics curve = 0.83 and 0.89, respectively) with higher specificity (92% and 93%, respectively) than sensitivity (60% and 69%, respectively).

The DESCARD tool might be effective in screening of patients at risk of postoperative delirium and can be easily used by all nonpsychiatrists involved in the care of cardiac surgery patients.