Henry the County Extension Agent was making the rounds of the feed stores when he ran into one of the local ranchers he hadn’t seen in a while. “Say, Jake,” he said, “I’m hosting a seminar next week over at the Grange and one of the experts from down at the University is coming in to talk about some new ideas that’ll surely make you a better rancher. Think I can count on you to attend?”
Jake paused a moment before he gave his thoughtful reply. “Not sure it wouldn’t just be a waste of time – I already ranch just about half as good as I know how.”
Perhaps in our more cynical moments we all feel a little bit like Jake. If you’re attending the Conference this week, then congratulations for bucking complacency. If not – well, we miss you.
I’ve always viewed the preconference workshops as a justifiable luxury. Some, like this morning’s ‘Building Effective Hospice and Palliative Care Teams,’ are just downright fun; others, like this afternoon’s ‘Challenging Medication Management Issues at the End of Life’ are considerably more academic. Unfortunately, the lack of access to handouts (they weren’t yet online at the time of the presentation) brings with it a difficult choice — listen carefully and pick up what gems you can, or scribe furiously, trying to get down data (and risk losing concepts.)
Anyhow, here are a few concepts that I extracted from the afternoon:
Drug-drug interaction effects can mimic imminent death (so can severe constipation). Elderly patients and those with organ failure have a combination of homeostenosis and a much narrower therapeutic range for many medications.
Interactions can be a result of either pharmacokinetics (CYP-inducers, e.g.) or pharmacodynamic.
Antihistamines (among a huge number of other medication classes) induce constipation. (Another reason for those of us sufffering from seasonal allergies to be miserable.) Hey, diphenhydramine lowers the seizure threshold, too.
PCA studies have shown that there is a 40-fold variation in need for opiates in post-op pain among individuals, all other things being equal. (But you probably wouldn’t get away with ordering ‘morphine 2-80 mg IV q 4 hours’.) Dose ranges are subject to interpretation by the nurse in any event, and there is no evidence that range orders really work to control pain. Consider something like ‘2 mg for pain less than 5 and 4 mg for pain greater than 5’.
Patients on multiple opiates pose a special challenge, but usually provide an opportunity for simplication. Do err on the side of lower in the case of long-acting opiates, and provide plenty of prn meds for breakthrough. Then reassess after a few days and consider adjustments in doses of long-acting agents.
—breaking news— The slides have just appeared online with two more
presentations to go. Better late than never?
Picking up again…
Methadone is a great drug for analgesia, but interactions with other medications are a big concern. QTc prolongation is also a concern, and attention should be paid to cardiac history and family history of sudden death.
Olanzapine works for nausea. (I did not know that…)
In nursing homes the abbreviation prn may mean ‘patient receives nothing.’ (I’ve never heard that one before.)
Changing a patient from another opiate to methadone requires a non-linear conversion. There are a number of different protocols which work, but the hallmark of any is that the patient be closely monitored during the transition, since respiratory depression may develop out of proportion to the analgesic effect. Adjustments more often than q 5-7 days probably have more potential for harm than good, so be sure that there is a reasonable breakthrough pain control strategy (prn methadone if in a closely monitored setting, otherwise prn narcotic of choice.)
All in all a great summary of some pharmacological concepts that I haven’t explicitly considered in some time. I’ve picked up a couple of new approaches to add to my pharmacologic armamentarium, and each time I hear the methadone pep talk I get a little more comfortable with a medication that I still treat with great respect. Maybe when I get home I’ll be able to practice a little more than half as good as I know how.
Michael Moffitt, MD, PhD
Scott & White Hospice
Temple, TX
mmoffitt@swmail.sw.org