Post-operative delirium Surgery Post-operative problems
Conditions
Interventions
5 mg of donepezil (DPZ) or matched placebo once daily for seven days.
Sponsors
Imperial College London (UK)
Eligibility
Inclusion criteria
Inclusion criteria: 1. Awaiting elective total hip or knee replacement 2. 65 years old or over 3. Valid written informed consent
Exclusion criteria
Exclusion criteria: 1. Subjects with delirium as defined by the Confusion Assessment Method (CAM) 2. Subjects undergoing revision/complex hip/knee surgery 3. Subjects who are deaf, visually impaired or have insufficient English to the extent where they cannot complete the study assessments 4. Subjects with moderately severe cognitive impairment at baseline (i.e. Mini Mental State Examination [MMSE] less than 20) 5. Subjects with alcohol dependence syndrome (International Classification of Diseases [ICD-10] definition) 6. Subjects with severe nausea and vomiting precluding the use of DPZ 7. Subjects currently taking cholinesterase inhibitors 8. Subjects taking antipsychotic/neuroleptic medication that may mask symptoms of delirium 9. Hypnotics or anxiolytics initiated less than a month ago 10. Subjects with a known hypersensitivity to DPZ (piperidine derivatives or any excipients used in its formulation ? or that of the placebo) 11. Severe bladder outflow obstruction 12. Spinal anaesthesia during surgery 13. Subjects with cardiac problems that contraindicate the prescription of cholinesterase inhibitors: 13.1. Sick sinus syndrome 13.2. Resting pulse of less than 50 13.3. Supraventricular conduction defects
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| The primary endpoint of the study will be the incidence of post-operative delirium. Patients will be considered as a case of delirium if at any point during the course of follow up (to Day seven) they develop an episode of delirium. A risk ratio will be calculated. Delirium will be diagnosed using the Confusion Assessment Method (CAM) as the primary outcome variable. This is the most widely used instrument for the detection of delirium in the acute hospital setting. It has a sensitivity of 94-100% and a specificity of 90-95% and generates a Diagnostic and Statistical Manual of mental disorders - Fourth Edition (DSM IV) diagnosis of delirium. | — |
Secondary
| Measure | Time frame |
|---|---|
| 1. The severity of delirium: severity of delirium will be measured by the Delirium Symptom Index (DSI) post- operatively twice a day (morning and afternoon) up to day six. The DSI is a seven item clinician rated scale which measures the severity of delirium and is sensitive to change. It has good internal consistency and inter-rater reliability 2. Length of delirium: this will be measured as the total number of days on which a patient achieves DSM IV ?caseness? for delirium using the CAM. It will be considered that the patient has had delirium that day if either of the two assessments in a 24-hour period were positive for delirium 3. Presence of subsyndromal delirium and behavioural symptoms: this will be measured using the CAM and be defined as any symptoms of new disorientation, disturbance of attention or perceptual or behavioural disturbance that do not meet the full criteria for delirium 4. Changes in cognition: the Mini-Mental State Examination (MMSE) will be used post- operatively once a day (morning up to day six). This is the most widely used screening test for cognitive impairment. It has a maximum score of 30 and assesses a range of cognitive skills. The MMSE has high inter-rater reliability (0.8) 5. Length of hospital stay: this outcome will indicate whether delirium prophylaxis using DPZ may have health economic benefits. Length of hospital stay will be measured in days | — |
Countries
United Kingdom
Outcome results
None listed