Incidence and Predictors of Delirium After Cardiac Surgery

Official Title: “Incidence and Predictors of Delirium After Cardiac Surgery: A Prospective Observational Cohort Study”

The objective of the present research is to evaluate the incidence and independent predictors of delirium observed among patients after cardiac surgery. Moreover, to asses the sensitivity and specificity of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria (DSM-IV) and International Statistical Classification of Diseases and Health Related Problems - Tenth Revision criteria (ICD-10), and the cut-off values of the Memorial Delirium Assessment Scale (MDAS) and Delirium Index (DI) in diagnosing postoperative delirium.

Since 1954, the issue of delirium as a complication following cardiac surgery has been extensively investigated. Despite this, postoperative delirium is still a serious event that results in higher morbidity and mortality rates, and prolongs hospitalisation.

Moreover, there is a considerable discrepancy between studies on the incidence and risk factors of delirium among cardiac surgery patients.The first potential reason for this observation is retrospective design of some studies, secondly, the modest number of participants in numerous prospective studies which does not provide strong statistical power to select patients with delirium and detect risk factors of this complication.

Unfortunately, reports with a more considerable number of patients often have methodological limitations. Additionally, in previous studies authors usually analyzed pre- and intraoperative variables ignoring potential postoperative risk factors of delirium. Finally, some variables which seem to have a crucial role in aetiology of delirium after cardiac surgery, particularly perioperative hypoxia, anaemia, and preoperative psychiatric disorders like depression and cognitive impairment, have not been properly investigated to date.

Therefore, we made an effort to design a prospective study on the incidence and predictors of delirium after different types of cardiac surgery, conducted by experienced investigators, and with the use of valid diagnostic tools.To our knowledge this is the first research pointing out the association between preoperative psychiatric comorbidity, anaemia and postoperative hypoxia, and delirium after cardiac surgery.

Arms, Groups and Cohorts in this Clinical Trial

• : Cardiac surgery patients
  • Individuals consecutively scheduled for cardiac surgery

Primary Measures

• MMSE and MINI - to assess cognitive performance and psychiatric comorbidity; DSM-IV and ICD-10 criteria; MDAS and DI - to estimate the incidence and severity of postoperative delirium;
  • Time Frame: one day before surgery; from the 2nd to the 6th day after surgery
    Safety Issue?: Yes

Inclusion Criteria:

• Patients 18 years old and older
• Patients who signed an informed consent
• Patients scheduled for cardiac surgery with extracorporeal circulation (coronary-artery bypass grafting (CABG), cardiac valve replacement (CVR), combined
• CABG + CVR, excision of cardiac myxoma)

Exclusion Criteria:

• Patients who refuse to participate before or after operation
• Patients who undergo urgent surgery
• Patients in poor general condition
• Patients with preoperative dementia, delirium or illiterate

Gender Eligibility for this Clinical Trial: Both

Minimum Age for this Clinical Trial: 18 Years

Maximum Age for this Clinical Trial: N/A

Are Healthy Volunteers Accepted for this Clinical Trial?: No

Lead Investigator: Medical Universtity of Lodz Other

Overall Clinical Trial Officials and Contacts

Jakub Kazmierski, PhD Principal Investigator Department of Old-Age Psychiatry and Psychiatric Disorders, Medical University of Lodz, Poland  

Information obtained from ClinicalTrials.gov on February 12, 2012

Link to the current ClinicalTrials.gov record. http://clinicaltrials.gov/show/NCT00784576

Study ID Number: 502-11-429

ClinicalTrials.gov Identifier: NCT00784576

Health Authority: Poland: Ministry of Health