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.