Studies that compared length of survival in sedated and non-sedated terminally ill adult patients with cancer were eligible for inclusion. Studies had to present a reliable measurement of outcome. Case studies, letters, reviews, editorials and studies that focused on euthanasia and assisted suicide, ethical aspects or opinions were not eligible.
The included studies were based at various locations (hospital, hospice, acute palliative care unit, home). Reasons for sedation included breathlessness, dyspnoea, pain, delirium, nausea/vomiting, mental anguish, insomnia, severe itching, anxiety/psychological distress/depression, bleeding, restlessness, psychological and physical distress. The most commonly used drug was midazolam; other drugs used for sedation were haloperidol, chlorpromazine, morphine, methotrimeprazine, propofol, phenobarbital, diazepam and other benzodiazepines. Drugs were given in proportional, intermittent or continuous modes. Where reported, mean duration of sedation ranged from 0.8 to 12.6 days and median length of sedative use ranged from 0.9 to 5.0 days.
Two reviewers independently assessed studies for inclusion; disagreements were resolved by discussion and consensus.