RESUMO
The numbers of patients dying with end-stage renal disease (ESRD), particularly those managed conservatively (without dialysis) or withdrawing from dialysis is increasing rapidly in developed countries. There is growing awareness of the extensive symptom control needs of these patients. Pain is a common problem, and has been both under-recognized and under-treated. It is challenging to manage, largely because of the constraints very poor renal function places on use of medication. Although pharmacological reviews of opioid use in renal failure have been published, there is a need for clinical recommendations to aid palliative and renal specialists in providing effective pain control. This review describes the pharmacological evidence for and against the use of the different opioid medications, and translates this into clinical recommendations for ESRD patients managed conservatively, not for those on dialysis for whom there are different pharmacological considerations. Acetaminophen (paracetamol) is recommended at Step 1 of the World Health Organization ladder. Of the Step 2 analgesics, tramadol is the least problematic, although dose reduction and increased dosing interval are required, and caution should be exercised. Of the Step 3 analgesics, fentanyl, alfentanil and methadone are recommended. There is limited evidence for buprenorphine, although theoretical reasons why it may be a good choice for these patients. Hydromorphone and oxycodone cannot be recommended because of extremely limited evidence, although each is likely a better choice than morphine or diamorphine. Morphine and diamorphine themselves are not recommended because of known accumulation of potentially toxic metabolites.
