**7. Conclusion**

is excreted via kidneys, of which 8% as oxycodone and the remaining as metabolites. In CKD patients, dose reduction is necessary, if GFR is less than 60 mL/min, the serum concentration of oxycodone reaches 50%; thus, starting dose should be 30% and titrated with lengthening the dosing interval. In stage 5 CKD patients, it is best to be avoided, although it is removed by dialysis. **Methadone** was traditionally used in the treatment of opioid addiction but now increasingly prescribed for outpatient chronic pain patients. It has good bioavailability (mean value 75%), although pharmacokinetics greatly varies among individuals due to differences in CYP450 enzyme activity (which depends on genetics or patient's other medications). Eventually it undergoes N-demethylation in the liver by CYP3A4 to inactive metabolite. It has long life, elimination half-life reaching approximately 22 hours. Limited number of studies showed that no significant accumulation in CKD patients occurs, making it a suitable medication for renally impaired population. Therefore no dose adjustments are mandatory, except in cases

**Buprenorphine** is also extensively metabolized by the liver producing weak analgesic, norbuprenorphine. Thirty percent of both parent drug and metabolite is cleared by kidneys. In CKD patients, it can be used in regular doses in stages 1–4 but in stage 5 used with caution

**Fentanyl** is considered a safe opioid in CKD patients, and recommended route is transdermal patch (except in ESRD when it is avoided), but dose reduction should be up to 50% in severe to moderate CKD. It is mainly metabolized by oxidation in the liver, producing inactive metabolite, norfentanyl; 75% is excreted within 3 days. It is not dialyzed by either hemo- or peritoneal dialysis. **Alfentanil** is similar to fentanyl, can be also used as a transdermal patch, and does not produce active metabolites. It is short and fast acting and also cannot be removed with dialysis.

When prescribing any opioid, all clinicians must follow safety precautions, explaining to patient treatment goals, using lowest dose to reach pain relief, following the patient regularly

Non-pharmacological approach to pain management starts with working on psychological components of the pain. Devine et al. analyzed 191 studies and confirmed significance of psychological and educational care of surgical patients and its role in managing acute postoperative pain. It included providing patients with proper information about procedures and the expected level of pain, instructing them on proper coughing and breathing techniques,

Transition from acute to chronic pain conditions also involves several psychological factors

Many kinds of questionnaires and tests were developed to be applied in chronic pain, discussion of which is beyond the scope of this chapter. Generally, psychological management of chronic pain patients should be carried out with the help of certified psychologist or psychiatrist.

when the patient is taking other CYP450-altering medications.

No dose reduction is required in CKD patients in any level.

such as depressive state, somatization, or significant distress [40].

and frequent questioning of opioid need.

108 Pain Management in Special Circumstances

and providing emotional support [39].

**6. Non-pharmacological pain control**

and monitoring. It is dialyzed by both hemo- and peritoneal dialysis.

A considerable number of CKD patients experience acute pain at some point of their life, and even bigger portion of this population suffer from chronic pain. It is apparent from epidemiologic studies that pain can be experienced by more than 50% of CKD patients and greatly affects their quality of life. Moreover, poor pain control may lead to exacerbation of other psychological symptoms and contribute to further patient deterioration. If it is relatively clear how to manage acute pain in hospitalized patients, chronic pain remains mostly understudied and not fully understood. WHO stepwise approach to treating cancer pain may be tailored to CKD patients considering disturbances of pharmacodynamics of most medications in renal impairment. When there is a need to prescribe opioids, all precautions for side effects and addiction prevention must be taken. Pain practitioners should actively advocate non-pharmacological pain management techniques in appropriate patients.
