FAST FACT AND CONCEPT #54: Opioid Infusions in the Imminently Dying Patient

2nd Edition

Authors: Elizabeth Weinstein, Robert Arnold, MD and David E. Weissman, MD

Opioid infusions, either IV or SQ (see FF #28), can provide smooth and efficient control of distressing pain or dyspnea in the imminently dying patient. Opioids correctly titrated to provide symptom relief will not cause respiratory depression (see Fast Facts #8). It is common for physicians to order an opioid infusion in the dying patient as follows: “start morphine infusion at 1 mg/hr, titrate to effect”. This type of order is pharmacologically unsound and unsafe; hospitals should adopt clinical practice guidelines that meet current national standards. The following is a step by step approach to rational opioid infusion prescribing in the dying patient; the following information is most appropriate for morphine or hydromorphone (Dilaudid) infusions; Fast Facts #75 and #86 discuss the use of methadone.

First, before starting an opioid infusion, calculate an equianalgesic dose of currently used opioids; then convert this to an equianalgesic basal rate. (Example: patient on MS Contin, 60 mg q12, now unable to swallow; 60 mg q 12 = 120 mg/24 hours po morphine = 40 mg IV morphine/24 hours = approximately 2 mg/hr IV infusion basal rate).

Second, if the current opioid dose is not effective, dose escalate the basal dose by 25-100% (see FF #20).

Third, if the patient is opioid naïve or when increasing the basal rate above the current equianalgesic rate, give a loading dose when starting the infusion (Example: for a 1 mg/hr basal rate, give 2-5 mg loading dose). (see Portenoy reference for additional guidelines)

Fourth, choose a bolus (aka rescue or PCA dose). This can be a nurse initiated bolus dose when using a standard IV infuser, or a patient, nurse or family initiative bolus using a PCA device (Note: even though the dying patient may be unable to press the button, the nurse or family members can use the PCA device, depending on local hospital policy). Based on patterns of breakthrough pain, a bolus dose of 50% - 150% of the hourly rate is a place to start. For example, for a morphine infusion of 2 mg/hr, choose a starting bolus dose of 1-3 mg.

Fifth, choose a dosing interval. The peak analgesic effect from an IV bolus dose is 5-10 minutes; thus, the dosing interval (aka Lockout interval for a PCA device) should be in the range of 10-20 minutes.

Sixth, reassess for desired effect vs. side effects every 10-15 minutes until stable. Adjust bolus dose size every 30-60 minutes until desired effect is achieved.

Seventh, reassess the need for a change in the basal rate no more frequently than every 6-8 hours; use the number of administered bolus doses as a rough guide when calculating a new basal rate—however, never increase the basal rate by more than 100% at any one time. When increasing the basal rate, always administer a loading dose so as to more rapidly achieve steady-state blood levels.

The above guidelines should be thought of solely as a rough guide; differences in age, renal and pulmonary function and past responses to opioids must be considered when developing an appropriate analgesic treatment plan. When patients become anuric close to death, continuous dosing may be discontinued in favor of bolus dosing to prevent metabolite accumulation and agitated delirium.

References

1. Cancer pain relief and palliative care. Report of a WHO Expert Committee. World Health Organ Tech Rep Ser 1990;804:1-75.
2. Levy M. Pharmacologic treatment of cancer pain. N Engl J Med 1996;335:1124-32.
3. Management of cancer pain: adults. Clin Pract Guideline Quick Ref Guide Clin 1994:1-29.
4. Portenoy, RK. Continuous Infusion of Opioid Drugs in the Treatment of Cancer: Guidelines for Use. J Pain Symptom Manage 1986;1: 223-228.
5. See FF #28 for references regarding subcutaneous infusions.

Fast Facts were edited by David Weissman MD, Palliative Care Center, Medical College of Wisconsin until January 2007.  For comments/questions write to the current editor, Drew Rosielle MD: drosiell@mcw.edu. The complete set of Fast Facts is available at EPERC: www.eperc.mcw.edu

Copyright/Referencing Information: Users are free to d ownload and distribute Fast Facts for educational purposes only. Citation for referencing: Weinstein R, Arnold R, Weissman DE. Fast Facts and Concepts #54, September 2006. End-of-Life/Palliative Education Resource Center: http://www.eperc.mcw.edu.

Creation Date: 11/2001

Purpose: Instructional Aid, Self-Study Guide, Teaching

Audience(s)

ACGME Competencies: Medical Knowledge, Patient Care

Keyword(s): Pain>opioids