I'm Charles von Gunten, Provost of The Institute for Palliative Medicine at San Diego Hospice. I want to talk about getting the pain under control quickly when there's a pain crisis. We've called this a "pain code."
Imagine a patient who has advanced cancer who has been admitted to the hospital complaining of 10 out of 10 pain. Your goal is to get the pain under control quickly. The most important fact to remember is this -- the time to pain control is the same as the time to the maximum concentration of the opioid in the blood.
So for a drug such as morphine given intravenously, the time to maximum concentration is 8 minutes. Therefore, successive doses of morphine can be given every 8 minutes. For someone whose pain is completely out of control, 10 out of 10, you want to double the dose to get that pain under control.
So for example, with the patient I described, with 10 out of 10 pain, he might have been on a patient-controlled analgesia dose of 1 mg of morphine. You want to double it to 2 mg. If after 8 minutes that pain is not controlled, you double it again. That would be a 4-mg dose. Wait 8 minutes. If the patient is not experiencing any relief, then you want to double it again to 8 mg. If the patient is still not getting any relief after another 8 minutes, double it again to 16 mg.
The point here is you're doubling the dose of the opioid at the level of the receptor. When the patient begins to describe relief, you found the dose that is controlling that person's pain.
The most frequent mistake that people make is they dose every half-life. When someone is in a pain crisis, you want to get on top of that pain quickly. You want to avoid the demoralization that comes from not being able to deal with the pain right away.
So the key fact to remember is dose every time to maximum concentration. For morphine, for hydromorphone, and for intravenous fentanyl, that's every 8 minutes. If you are giving it subcutaneously, that would be every 30 minutes. And if you were giving it orally, it would be every hour. But the key point is dose every time to maximum concentration and double the dose until the patient reports relief.
This is Charles von Gunten, Provost of The Institute for Palliative Medicine. Thanks for your commitment to controlling pain. And thanks for watching this video.
Cite this: Charles F. von Gunten. Pain Code: Get Pain Under Control Quickly - Medscape - Sep 08, 2011.