To Örebro University

Background: Depression is common in patients with cardiac disease. Depression is a risk factor for developing postoperative delirium, a common and serious complication to cardiac surgery.

Objectives: The aim was to evaluate if screening tools for depression can be used to predict postoperative delirium after cardiac surgery.

Methods: This was a prospective population-based pilot study including 26 patients between 23 and 80 years of age undergoing cardiac surgery in Sweden during 2018. The day before surgery the participants filled out the depression screening instruments Hospital Anxiety and Depression Scale and Patient Health Questionnaire. After discharge the patient charts were examined for documentation of symptoms of delirium.

Results: Five (20%) patients screened positive regarding depression using the Hospital Anxiety and Depression Scale and 7 patients (27%) screened positive using The Patient Health Questionnaire. Four (22%) patients showed symptoms of postoperative delirium, none of them screened positive for depression prior to surgery.

Conclusion: We found no difference between the questionnaires PHQ-9 and HADS regarding identifying depressive symptoms. Moreover, we found that post-operative delirium, to a certain extent, can be detected by reading the patient́s charts postoperatively. However, this pilot study showed that screening tools for delirium need to be better implemented.