Objective: This prospective study documents the use of methadone as part of an opioid rotation strategy in patients with uncontrolled pain and severe delirium admitted for terminal care to a tertiary cancer palliative care hospital.
Methods: We reviewed the treatment of 20 patients with severe pain and delirium at the end of life who's delirium did not improve 24 h or longer after starting a neuroleptic medication.
Results: Ten male and 10 female patients, 47 to 77 years old, were rotated or "switched" to methadone due to uncontrolled pain in the setting of delirium, limiting further opioid dose escalation. At 2 weeks, a total of 10 patients had expired. Of the 10 patients who were alive 2 weeks after starting methadone, 7 patients were stable on an average of 1.1 mg/h methadone, 2 patients were restarted on morphine IV and one on Percocet. The calculated average equianalgesic dose of methadone was 9% (2%-17%) of the previous morphine-equivalent dose. Of the 20 patients who were switched to methadone for what appeared to be terminal delirium, the pain control was significant in 15, moderate in 3, and unchanged in 2 patients. Average analgesia was good to excellent (average Numeric Analog Scale rating [NAS] decreased from 8.2 to 2.5). Sedation had decreased from 1.65 to 0.55 on a scale of 0 to 3. Of the 20 patients, improvement of cognitive status was significant in 9, moderate in 6, partial in 2, and none in 3 patients. The Memorial Delirium Assessment Scale (MDAS) showed improvement from an average of 23.6 prior to the switch to 10.6 3 days after. Decreased alertness on methadone was devoid of agitated features.
Significance of results: Our study suggests that methadone can be effective in the treatment of both refractory pain and what appears to be terminal delirium. Most patients in our group had at least a short-term improvement in mental status as well as significant and lasting improvement in analgesia.