Safety of morphine administration in hemodialysis patients


It is generally believed that IV "morphine" administration in dialysis patients is acceptable as opposed to other analgesics especially "demerol" (meperidine) or its European counterpart "biperidine" which are apparently stricly contraindicated in this population of patients. In my experience, some ESRD patients given morphine sulfate intravenously (10 - 15 mg over 24 hrs) for pain control, develop respiratory depression along with mental obtundation, sometimes requiring eventual intubation and ventilation for a brief period of time, followed by a gradual recovery.

In some of these cases, although morphine overdose is suspected, naloxone (narcan) administration is not apprently effective . Is IV morphine realtively or completely contra-indicated in ESRD patients? Are there any published or conventional guidelines for morphine dose adjustment? Can naloxone contribute to worsening of morphine sulfate overdose symptoms? Are there safer but equally efficient options for pain contol e.g. post-operatively in ESRD patients?

Kamyar Kalantar-Zadeh, MD
UCSF Division of Nephrology


Answer by George R. Aronoff, M.D., FACP and Michael E. Brier, Ph.D.
(University of Louisville Kidney Disease Program)<

The major pathway for morphine elimination is hepatic conjugation with glucuronic acid. Little morphine is excreted unchanged in the urine. Consequently, renal insufficiency does not effect the elimination rate of morphine. However, the kidneys mostly excrete the polar glucuronide metabolites of morphine and these may substantially accumulate in patients with renal failure. The most active of the morphine metabolites is morphine-6-glucuronide, and may even be more potent than morphine (1). The elimination half-life of the polar metabolites of morphine may be increased 10-fold in patients with renal failure from a mean of four hours in patients with normal renal function to more than 40 hours (2).

Because of the accumulation of active morphine metabolites, increased sedation has been reported in renal failure patients receiving morphine (3). This effect might be particularly expected after prolonged treatment with repeated doses. Although the extent of extra corporeal removal of morphine and its glucuronide metabolites by hemodialysis, peritoneal dialysis and continuous filtration is not known, the compounds are relatively small molecules and are not known to be highly protein bound. Consequently, we might expect some elimination by these techniques.

Our current recommendations for morphine are to reduce the dose to about 75% of the usual dose in patients with creatinine clearances between 10 and 50 mL/min and to about 50% of the usual dose in patients with creatinine clearances less than 10 mL/min (4). Morphine should be used with caution, particularly when given in repeated doses.

We suggest that meperidine be avoided in patients with renal failure because of the potential accumulation of nor-meperidine. Nor-meperidine is a polar metabolite, normally excreted by the kidneys, which has been reported to lower the seizure threshold.

George R. Aronoff, M.D., FACP
Michael E. Brier, Ph.D.
University of Louisville Kidney Disease Program

References
1. The Pharmacological Basis of Therapeutics. Gilman, et al., eds. 1990. Pergamon Press. New York

2. Drug Dosage in Renal Insufficiency. Gunter Seyfert, ed. 1991. Kluwer Academic Publishers. Norwell, MA.

3. Osborne RJ, et al. Morphine intoxication in renal failure: the role of morphine-6-glucuronide. Brit Med J Clin Res Ed 292(6536):1548-1549, 1986.   

4. Drug Prescribing in Renal Failure. Dosing Guidelines for Adults. Bennett, et. al., eds. 1994. American College of Physicians. Philadelphia, PA.

(October, 1997)


I had similar experience with morphine causing obtundation and excessive sedation. I still use at a much reduced dose for pain control. 1 to 2 mg SQ Q 6 hours PRN offers adequate pain control in most patients. The use of a Patient controlled analgesia (PCA) seems to avoid the problem with overdose .
Mohamed Salem
chicago, il usa-Sunday, March 01, 1998 at 05:39:09 (PST)