Pharmacological risk factors for delirium after cardiac surgery: a review.

Lurdes Tse,Kyle D Burns,Jill A Osborn,Stephan Kw Schwarz,Alasdair M Barr,Randell L Moore,John B Bowering,Carole M Richford

doi:10.2174/157015912803217332

Abstract

Purpose:The objective of this review is to evaluate the literature on medications associated with delirium after cardiac surgery and potential prophylactic agents for preventing it.Source:Articles were searched in MEDLINE, Cumulative Index to Nursing and Allied Health, and EMBASE with the MeSH headings: delirium, cardiac surgical procedures, and risk factors, and the keywords: delirium, cardiac surgery, risk factors, and drugs. Principle inclusion criteria include having patient samples receiving cardiac procedures on cardiopulmonary bypass, and using DSM-IV-TR criteria or a standardized tool for the diagnosis of delirium.Principal Findings:Fifteen studies were reviewed. Two single drugs (intraoperative fentanyl and ketamine), and two classes of drugs (preoperative antipsychotics and postoperative inotropes) were identified in the literature as being independently associated with delirium after cardiac surgery. Another seven classes of drugs (preoperative antihypertensives, anticholinergics, antidepressants, benzodiazepines, opioids, and statins, and postoperative opioids) and three single drugs (intraoperative diazepam, and postoperative dexmedetomidine and rivastigmine) have mixed findings. One drug (risperidone) has been shown to prevent delirium when taken immediately upon awakening from cardiac surgery. None of these findings was replicated in the studies reviewed.Conclusion:These studies have shown that drugs taken perioperatively by cardiac surgery patients need to be considered in delirium risk management strategies. While medications with direct neurological actions are clearly important, this review has shown that specific cardiovascular drugs may also require attention. Future studies that are methodologically consistent are required to further validate these findings and improve their utility.

Highlights

Delirium after cardiac surgery is associated with serious long-term medical consequences [1, 2] and high costs [3]
Preoperative antipsychotics, intraoperative fentanyl and postoperative inotropes are associated with higher rates of delirium, while intraoperative ketamine is associated with a lower rate of delirium
From the results of this review, it is clear that drugs taken perioperatively by cardiac surgery patients have either direct or indirect influence on the outcome of delirium

Summary

Introduction

Delirium after cardiac surgery is associated with serious long-term medical consequences [1, 2] and high costs [3]. It affects approximately 30% of cardiac surgery patients, reported incidences are variable [4,5,6,7,8,9,10,11]. Factors that have previously been identified as key, independent predictors of delirium after cardiac surgery include advanced age, pre-operative cognitive decline, atrial fibrillation, previous delirium as well as a sizeable list of other conditions and co-morbidities [13,14,15]. Given that many of these risk factors are non-modifiable, emphasis

Methods

Results

Conclusion