Feb 18, 2018
One of the stress points when a patient taking chronic opioids presents with acute pain is that we feel we have little to offer them. Are more opioids the answer? That's often what happens, but might not be the best next step. In this episode, Reuben Strayer presents the argument in favor of haloperidol for analgesia and why more opioids can do more harm than good.
In the introduction, preview of a project we're working on for Essentials of Emergency Medicine (May 15-17).
Opioid induced hyperalgesia: compared to those not taking opioids, patients on chronic opioids may have a more unpleasant experience when exposed to painful stimuli. In other words, they are more sensitive pain. The meds used to treat pain, actually worsen pain.
A patient who uses chronic opioids will have marginal gains in analgesia with escalating doses while getting closer to potentially lethal adverse effects.
Haloperidol is an analgesic option for patients taking chronic opioids.
Reuben's strategy for using haloperidol for analgesia in chronic opioid patients: 10 mg IM haloperidol if there is no IV, 5 mg IV if they have a line. If they don't fall asleep shortly after (or have improvement of pain) he repeats the dose. If that doesn’t work, he uses analgesic dose ketamine.
For analgesic dose ketamine in these patients, Reuben uses 30 mg IV. This may cross over into the 'recreational' or 'partial dissociation' dose where the patient can have disturbing psycho-perceptual effects. He has found that the pretreatment with haloperidol leads to less distress from these psycho-perceptual effects. For more information on ketamine dosing, see Reuben's post on the Ketamine Brain Continuum.
Haloperidol and the prolonged QTc: Butyrophenones (of which haloperidol is one) are known to prolong the QTc. Should we get an EKG prior to giving haloperidol to see if the QTc is already prolonged? Reuben feels that the negative effects of butyrophenone QTc prolongation are overblown and does not routinely get an EKG prior to giving haloperidol. This includes initial and subsequent doses. Take that with a grain of salt because there are many docs who do get an EKG before the first or second dose of haloperidol, especially if there is a known QTc prolonging drug on the patient's med list (like methadone). Some hospitals even have policies that before a second dose is given, there is a hard stop for EKG and QTc check.
Droperidol for analgesia
Early studies on Haloperidol for analgesia
Haloperidol for pain