Rivastigmine for the prevention of postoperative delirium in elderly patients undergoing elective cardiac surgery--a randomized controlled trial. Crit Care Med. 2009;37:1762-1768. [PMID: 19325490 DOI: 10.1097/CCM.0b013e31819da780]

Preventing postoperative complications in the elderly

Postoperative complications are directly related to poor surgical outcomes in the elderly. This review outlines evidence based quality initiatives focused on decreasing neurologic, cardiac, and pulmonary complications in the elderly surgical patient. Important anesthesia quality initiatives for prevention of delirium, the most common neurologic complication in elderly surgical patients, are outlined. There are few age-specific quality measures aimed at prevention of cardiac and pulmonary complications. However, some recommendations for adults can be applied to the geriatric surgical population. In the future, process measures may provide a more global assessment of quality in the elderly surgical population.

Effect of rivastigmine as an adjunct to usual care with haloperidol on duration of delirium and mortality in critically ill patients: a multicentre, double-blind, placebo-controlled randomised trial

BACKGROUND

Delirium is frequently diagnosed in critically ill patients and is associated with adverse outcome. Impaired cholinergic neurotransmission seems to have an important role in the development of delirium. We aimed to establish the effect of the cholinesterase inhibitor rivastigmine on the duration of delirium in critically ill patients.

METHODS

Patients (aged ≥18 years) who were diagnosed with delirium were enrolled from six intensive care units in the Netherlands, and treated between November, 2008, and January, 2010. Patients were randomised (1:1 ratio) to receive an increasing dose of rivastigmine or placebo, starting at 0·75 mL (1·5 mg rivastigmine) twice daily and increasing in increments to 3 mL (6 mg rivastigmine) twice daily from day 10 onwards, as an adjunct to usual care based on haloperidol. The trial pharmacist generated the randomisation sequence by computer, and consecutively numbered bottles of the study drug according to this sequence to conceal allocation. The primary outcome was the duration of delirium during hospital admission. Analysis was by intention to treat. Duration of delirium was censored for patients who died or were discharged from hospital while delirious. Patients, medical staff, and investigators were masked to treatment allocation. Members of the data safety and monitoring board (DSMB) were unmasked and did interim analyses every 3 months. This trial is registered with ClinicalTrials.gov, number NCT00704301.

FINDINGS

Although a sample size of 440 patients was planned, after inclusion of 104 patients with delirium who were eligible for the intention-to-treat analysis (n=54 on rivastigmine, n=50 on placebo), the DSMB recommended that the trial be halted because mortality in the rivastigmine group (n=12, 22%) was higher than in the placebo group (n=4, 8%; p=0·07). Median duration of delirium was longer in the rivastigmine group (5·0 days, IQR 2·7-14·2) than in the placebo group (3·0 days, IQR 1·0-9·3; p=0·06).

INTERPRETATION

Rivastigmine did not decrease duration of delirium and might have increased mortality so we do not recommend use of rivastigmine to treat delirium in critically ill patients.

FUNDING

ZonMw, the Netherlands Brain Foundation, and Novartis.

An approach to the patient with cognitive impairment: delirium and dementia

Patients with cognitive impairment can be divided into 2 broad groups: those with chronic cognitive decline (most likely diagnosable with a dementia) and those with acute cognitive changes (most likely experiencing a delirium). However, diagnosis in clinical practice is far more complicated than it is in textbooks. Perhaps the greatest hurdle in evaluating the cognitively impaired patient is the clarification of a cohesive history. Unfortunately, the cognitively impaired patient is most often unable to provide such a history, and in the absence of a reliable family member, friend, or caregiver to fill in the gaps, diagnostic clarity can be difficult to achieve. This article outlines the broad diagnostic spectra of delirium and dementia, reviews current understanding of their pathogenesis, and discusses useful diagnostic and therapeutic techniques.

Impact of an educational workshop upon attitudes towards pharmacotherapy for delirium

BACKGROUND

There is uncertainty regarding the optimal use of pharmacological strategies in delirium particularly regarding preferred agents, duration of treatment and effectiveness in different populations.

METHODS

Attitudes towards delirium pharmacotherapy were investigated before and after an educational workshop using the format of a television game show.

RESULTS

Most respondents (65/66) reported psychotropic use with variable frequency (median 60%). Antipsychotic use was inversely related to perception of supporting evidence (p = 0.02). Respondents rated sedative (38%) and antipsychotic (33%) effects as the principal mechanism of action rather than a specific neurochemical anti-delirium effect (21%). Haloperidol was the preferred first-line agent (65%). Suggested continuation treatment after symptom resolution was three days. Eleven respondents had used psychotropics prophylactically. Antipsychotic use was influenced by concerns regarding potential for extrapyramidal (52%), sedative (32%), cerebrovascular (30%) and metabolic (8%) effects. Post-workshop concerns regarding extrapyramidal effects were reduced with a more positive general attitude towards pharmacological interventions, especially in hypoactive presentations (61%) and prophylactically in high-risk patients (56%).

CONCLUSIONS

Attitudes towards key aspects of delirium pharmacotherapy vary considerably and relate to concerns regarding side effect potential more than perceived mechanism of action. Educational interventions can impact positively upon attitudes.

Delirium in intensive care unit patients

Delirium is defined as a disturbance of consciousness with cognitive changes or perceptual disturbances, which has developed over a short period of time, and is caused by a medical condition or a postsurgical state. Although historically dismissed as an inconvenient and transient problem, recent studies have reported that delirium is associated with more complications, increased length of hospital stay, and higher mortality. Although delirium is a prevalent condition after cardiothoracic surgery and in the intensive care unit (ICU), the condition appears to be largely underdiagnosed. Several detection tools have been developed for routine monitoring of delirium by nonpsychiatric personnel in the ICU, such as the Confusion Assessment Method for the Intensive Care Unit and the Intensive Care Delirium Screening Checklist. Management includes treatment of underlying disorders, nonpharmacological measures and symptomatic drug therapy. There is a need for well-designed randomized, double-blind, placebo-controlled trials on drug treatment.

Modifiable and nonmodifiable risk factors for postoperative delirium after cardiac surgery with cardiopulmonary bypass

OBJECTIVES

Postoperative delirium after cardiac surgery is associated with increased morbidity and mortality as well as prolonged stay in both the intensive care unit and the hospital. The authors sought to identify modifiable risk factors associated with the development of postoperative delirium in elderly patients after elective cardiac surgery in order to be able to design follow-up studies aimed at the prevention of delirium by optimizing perioperative management.

DESIGN

A post hoc analysis of data from patients enrolled in a randomized controlled trial was performed.

SETTING

A single university hospital.

PARTICIPANTS

One hundred thirteen patients aged 65 or older undergoing elective cardiac surgery with cardiopulmonary bypass.

INTERVENTIONS

None. MEASUREMENTS AND MAINS RESULTS: Screening for delirium was performed using the Confusion Assessment Method (CAM) on the first 6 postoperative days. A multivariable logistic regression model was developed to identify significant risk factors and to control for confounders. Delirium developed in 35 of 113 patients (30%). The multivariable model showed the maximum value of C-reactive protein measured postoperatively, the dose of fentanyl per kilogram of body weight administered intraoperatively, and the duration of mechanical ventilation to be independently associated with delirium.

CONCLUSIONS

In this post hoc analysis, larger doses of fentanyl administered intraoperatively and longer duration of mechanical ventilation were associated with postoperative delirium in the elderly after cardiac surgery. Prospective randomized trials should be performed to test the hypotheses that a reduced dose of fentanyl administered intraoperatively, the use of a different opioid, or weaning protocols aimed at early extubation prevent delirium in these patients.