Adverse effects in hospice patients with chronic kidney disease receiving hydromorphone

Revision of Pharmacological Treatment Recommendations for Cancer Pain: Clinical Guidelines from the Japanese Society of Palliative Medicine

Background: Pain is one of the most common symptoms in cancer patients. The Japanese Society for Palliative Medicine (JSPM) first published its clinical guidelines for the management of cancer pain in 2010. Since then, more research on cancer pain management has been reported, and new drugs have become available in Japan. Thus, the JSPM has now revised the clinical guidelines using a validated methodology. Methods: This guideline was developed through a systematic review, discussion, and the Delphi method, following a formal guideline development process. Results: Thirty-five recommendations were created: 19 for the pharmacological management of cancer pain, 6 for the management of opioid-induced adverse effects, and 10 for pharmacological treatment procedures. Due to the lack of evidence that directly addressed our clinical questions, most of the recommendations had to be based on consensus among committee members and other guidelines. Discussion: It is critical to continue to build high-quality evidence in cancer pain management, and revise these guidelines accordingly.

Opioids for chronic pain management in patients with dialysis-dependent kidney failure

Chronic pain is highly prevalent among adults treated with maintenance haemodialysis (HD) and has profound negative effects. Over four decades, research has demonstrated that 50-80% of adult patients treated with HD report having pain. Half of patients with HD-dependent kidney failure (HDKF) have chronic moderate-to-severe pain, which is similar to the burden of pain in patients with cancer. However, pain management in patients with HDKF is often ineffective as most patients report that their pain is inadequately treated. Opioid analgesics are prescribed more frequently for patients receiving HD than for individuals in the general population with chronic pain, and are associated with increased morbidity, mortality and health-care resource use. Furthermore, current opioid prescribing patterns are frequently inconsistent with guideline-recommended care. Evidence for the effectiveness of opioids in pain management in general, and in patients with HDKF specifically, is lacking. Nonetheless, long-term opioid therapy has a role in the treatment of some patients when used selectively, carefully and combined with an ongoing assessment of risks and benefits. Here, we provide a comprehensive overview of the use of opioid therapy in patients with HDKF and chronic pain, including a discussion of buprenorphine, which has potential as an analgesic option for patients receiving HD owing to its unique pharmacological properties.

A General Picture of Cucurbit[8]uril Host-Guest Binding

Describing, understanding, and designing complex interaction networks within macromolecular systems remain challenging in modern chemical research. Host-guest systems, despite their relative simplicity in both the structural feature and interaction patterns, still pose problems in theoretical modeling. The barrel-shaped supramolecular container cucurbit[8]uril (CB8) shows promising functionalities in various areas, e.g., catalysis and molecular recognition. It can stably coordinate a series of structurally diverse guests with high affinities. In this work, we examine the binding of seven commonly abused drugs to the CB8 host, aiming at providing a general picture of CB8-guest binding. Extensive sampling of the configurational space of these host-guest systems is performed, and the binding pathway and interaction patterns of CB8-guest complexes are investigated. A thorough comparison of widely used fixed-charge models for drug-like molecules is presented. Iterative refitting of the atomic charges suggests significant conformation dependence of charge generation. The initial model generated at the original conformation could be inaccurate for new conformations explored during conformational search, and the newly fitted charge set improves the prediction-experiment correlation significantly. Our investigations of the configurational space of CB8-drug complexes suggest that the host-guest interactions are more complex than expected. Despite the structural simplicities of these molecules, the conformational fluctuations of the host and the guest molecules and orientations of functional groups lead to the existence of an ensemble of binding modes. The insights of the binding thermodynamics, performance of fixed-charge models, and binding patterns of the CB8-guest systems are useful for studying and elucidating the binding mechanism of other host-guest complexes.

Patient and Healthcare Professional Satisfaction Ratings and Safety Profile of Sufentanil Sublingual Tablets for Treatment of Acute Pain: A Pooled Demographic Analysis

Objective

This analysis reports the healthcare professional global assessment (HPGA) and patient global assessment (PGA) scores and the adverse event (AE) profile by age, body mass index (BMI), sex, and race from the three Phase III registration studies for sufentanil sublingual tablet (SST) 30 mcg.

Methods

Global assessments and treatment-related AEs were analyzed from patients treated with SST 30 mcg for moderate-to-severe acute pain following surgery or in the emergency department (ED). Pooled data were analyzed across patient demographic subgroups.

Results

A total of 283 patients were included in the HPGA/PGA analyses. The majority underwent abdominal surgery, with the remaining patients undergoing orthopedic or “other” types of surgery. Overall, SST 30 mcg was highly rated by both healthcare professionals and patients across the demographic subgroups. A total of 323 patients were included in the safety evaluation. The majority of patients did not experience any SST-related AEs; however, those that did experienced common opioid-related side effects such as nausea, headache, dizziness, and vomiting. No patients experienced unexpected AEs or required the use of naloxone.

Conclusion

SST 30 mcg was highly rated and well tolerated across demographic subgroups with the majority of patients not experiencing any adverse event related to SST 30 mcg. These findings support the use of sublingual sufentanil in all adult patients, regardless of age, BMI, sex, or race for the treatment of moderate-to-severe acute pain.

Opioid Use in the Nondialysis Chronic Kidney Disease Population

Although pain is a common and burdensome condition in patients with chronic kidney disease (CKD), little is known about the use and safety of opioids in this patient population. Recommendations regarding opioid use in patients with CKD are based on pharmacokinetic data, extrapolation from non-CKD studies, and from clinical experience. Given the potential increased risk for opioid-related adverse events in patients with reduced kidney function, health care providers may be hesitant to prescribe opioids, resulting in inadequate pain control. This review summarizes current studies of opioid use in patients with CKD, highlights special considerations, and proposes an opioid prescribing strategy for this unique patient population. Specifically, oral hydromorphone, transdermal fentanyl, and buprenorphine should be considered as the first-line opioids for patients with CKD if opioid management is indicated. A stepwise approach such as the Screen-Quantify-Use opioids-Adjust-Reassess-Engage prescribing strategy proposed here is critical to ensure optimal pain control while minimizing the side effects and adverse events of opioids. The effects of opioids on clinically relevant outcomes in the CKD population remains to be explored in future studies.

The Role of Opioids in Pain Management in Elderly Patients with Chronic Kidney Disease: A Review Article

Chronic kidney disease (CKD) is a global public health problem. Pain is one of the most generally experienced symptoms by CKD patients. Pain management is a key clinical activity; nonetheless, insufficient pain management by health professionals keeps it up. Opioids as pain relievers are a class of naturally-derived and synthetic medications. They act through interactions with receptors in peripheral nerves. Numerous pharmacokinetic alterations happen with aging that influence drug disposition, metabolism, and quality of life. Acetaminophen alone, or combined with low-potency opioid dose is regarded as the safest pain-relieving choice for CKD. Morphine and codeine are probably eluded in renal impairment patients and used with excessive carefulness. Tramadol, oxycodone, and hydromorphone can be used by patient monitoring, while methadone, transdermal fentanyl, and buprenorphine seem to be safe to use in older non-dialysis patients with renal impairment. Consistent with the available literature, the main aim of this review was to explore the occurrence of chronic pain and its opioid treatment in CKD patients. According to this review, more and well-made randomized controlled trials are necessary to find appropriate opioid doses and explore the occurrence of side effects.

Safe Use of Opioids in Chronic Kidney Disease and Hemodialysis Patients: Tips and Tricks for Non-Pain Specialists

In patients suffering from moderate-to-severe chronic kidney disease (CKD) or end-stage renal disease (ESRD), subjected to hemodialysis (HD), pain is very common, but often underestimated. Opioids are still the mainstay of severe chronic pain management; however, their prescription in CKD and HD patients is still significantly low and pain is often under-treated. Altered pharmacokinetics and the lack of clinical trials on the use of opioids in patients with renal impairment increase physicians' concerns in this specific population. This narrative review focused on the correct and safe use of opioids in patients with CKD and HD. Morphine and codeine are not recommended, because the accumulation of their metabolites may cause neurotoxic symptoms. Oxycodone and hydromorphone can be safely used, but adequate dosage adjustments are required in CKD. In dialyzed patients, these opioids should be considered as second-line agents and patients should be carefully monitored. According to different studies, buprenorphine and fentanyl could be considered first-line opioids in the management of pain in CKD; however, fentanyl is not appropriate in patients undergoing HD. Tapentadol does not need dosage adjustment in mild-to-moderate renal impairment conditions; however, no data are available on its use in ESRD. Opioid-related side effects may be exacerbated by common comorbidities in CKD patients. Opioid-induced constipation can be managed with peripherally-acting-μ-opioid-receptor-antagonists (PAMORA). Unlike the other PAMORA, naldemedine does not require any dose adjustment in CKD and HD patients. Accurate pain diagnosis, opioid titration and tailoring are mandatory to minimize the risks and to improve the outcome of the analgesic therapy.

Influence of muscle mass on the estimation of glomerular filtration rate in Japanese terminal cancer patients

BACKGROUND

Estimated glomerular filtration rate (eGFR) based on serum cystatin C (Scys) is useful for patients with decreased muscle mass, but has been also reported to be affected by cancer. The usefulness of Scys in eGFR in terminal cancer patients with decreased muscle mass is unknown. Therefore, we analyzed appropriate eGFR formulae for terminal cancer patients.

METHODS

Study design was a retrospective observational study. Based on creatinine height index (CHI), 184 terminal cancer patients were stratified into CHI ≥ 90% (normal muscle mass, 59 patients); CHI 60-89% (mildly to moderately decreased muscle mass, 64 patients); and CHI < 60% (severely decreased muscle mass, 61 patients) groups. Twenty-four-hour creatinine clearance was measured and converted to the glomerular filtration rate (GFR) as a renal function measure. To estimate GFR, various eGFR formulae for Japanese were used: eGFR_Scys, eGFR_Scr5 and eGFR_Scr3, eGFR_average and eGFR_Scys-Scr, and eGFR_CG, based on Scys, serum creatinine (Scr), Scys and Scr combined, and Cockcroft-Gault formula (CG), respectively. Errors between measured and estimated values of renal function were verified using mean prediction errors (ME). When a 95% confidence interval (CI) of ME included 0, the accuracy of the eGFR formula was graded as good.

RESULTS

eGFR_Scys ME was 0.2 (95% CI lower limit - 3.7, upper limit 4.0) mL/min/1.73 m² in CHI 60-89% group and 9.2 (6.1, 12.9) mL/min/1.73 m² in CHI < 60% group. eGFR_Scys was most accurate among the eGFR formulae.

CONCLUSIONS

eGFR based on Scys was demonstrated as useful in terminal cancer patients with decreased muscle mass.

Opioid Management in Older Adults with Chronic Kidney Disease: A Review

Chronic pain, a common comorbidity of chronic kidney disease, is consistently under-recognized and difficult to treat in older adults with nondialysis chronic kidney disease. Given the decreased kidney function associated with aging and chronic kidney disease, these patients are at increased risk for drug accumulation and adverse events. Emerging research has demonstrated the efficacy of opioids in chronic kidney disease patients, but research specifically focusing on older, nondialysis chronic kidney disease patients is scarce. The primary objective of this review is to determine which oral and transdermal opioids are the safest for older, nondialysis chronic kidney disease patients. We discuss the limited existing evidence on opioid prescription in older, nondialysis chronic kidney disease patients and provide recommendations for the management of oral and transdermal opioids in this patient population. Specifically, transdermal buprenorphine, transdermal fentanyl, and oral hydromorphone are the most tolerable opioids in these patients; hydrocodone, oxycodone, and methadone are useful but require careful monitoring; and tramadol, codeine, morphine, and meperidine should be avoided due to risk of accumulation and adverse events. Because older adults with nondialysis chronic kidney disease are at increased risk for adverse events, vigilant monitoring of opioid prescription is critical. Lastly, collaboration among an interprofessional clinical team can ensure safe prescription of opioids in older adults with nondialysis chronic kidney disease.

Pooled Dosing and Efficacy Analysis of the Sufentanil Sublingual Tablet 30 mcg Across Demographic Subgroups for the Management of Moderate-to-Severe Acute Pain

PURPOSE

To aid nurses in dosing sufentanil sublingual tablet (SST) 30 mcg administered via a single-dose applicator, dosing requirements and efficacy of SST 30 mcg were analyzed across age, sex, race, and body mass index subgroups.

DESIGN

Patient characteristics were pooled from three postoperative studies (two placebo-controlled and one open-label) and one open-label emergency department study. Drug dosing and efficacy data were pooled from the postoperative studies.

METHODS

Efficacy was assessed through summed pain intensity difference to baseline during 12 hours across subgroups.

FINDINGS

Mean (standard deviation) drug doses administered from 0 to 12 hours was 3.9 (2.0) for SST 30 mcg and was less frequent for older (≥65 years) versus younger patients. The summed pain intensity difference to baseline during 12 hours was superior with SST 30 mcg versus placebo across all subgroups.

CONCLUSIONS

SST 30 mcg is a sublingual opioid analgesic with efficacy across demographic subgroups.

An Open-Label Study of Sufentanil Sublingual Tablet 30 Mcg in Patients with Postoperative Pain

Objective

To evaluate sufentanil sublingual tablet 30 mcg (SST 30 mcg) for postoperative pain in an older patient population with comorbidities.

Design

Multicenter, open-label, single-arm study.

Setting

Nine hospitals across the United States.

Subjects

Adults aged ≥40 years who had undergone a surgical procedure.

Methods

Patients with a postoperative pain intensity score ≥4 on an 11-point numeric rating scale (NRS) were allowed to enter the study and receive SST 30 mcg as requested for pain (minimum 60-minute redosing interval) over the 12-hour study period. Efficacy was assessed by patient reports of pain intensity on the NRS and a five-point pain relief scale. Safety was monitored throughout the study; plasma sufentanil concentrations were also measured. The primary efficacy endpoint was the time-weighted summed pain intensity difference (SPID) to baseline over 12 hours (SPID12).

Results

Of the 140 patients enrolled, 69% were American Society of Anesthesiologists Physical Class II or III, 44% had a body mass index (BMI) ≥30 mg/kg², and 29% had hepatic and/or renal impairment. Average age was 54.7 years (SD = 9.9 years), and average baseline pain intensity was 6.2 (SD = 1.9). The most common surgeries were abdominal (59%) and orthopedic (20%). The mean SPID12 was 36.0 (standard error of the mean = 2.2); mean scores were similar, regardless of age, sex, race, and BMI. From baseline, mean pain intensity decreased significantly starting 30 minutes postdose, and mean pain relief increased significantly starting 15 minutes postdose, remaining relatively stable through 12 hours (P < 0.001 at each time point). Four (3%) patients discontinued due to inadequate analgesia, and 45 (32%) patients had one or more adverse events that were considered possibly or probably related to the study drug. Mean plasma sufentanil concentrations were generally similar regardless of age, sex, BMI, or organ impairment status.

Conclusions

SST 30 mcg was effective and well tolerated for the management of moderate-to-severe acute postoperative pain.

Correlates of cognitive impairment in patients with chronic kidney failure on haemodialysis: Systematic review and meta-analysis

AIM

To review and identify correlates of cognitive impairment in patients with chronic kidney failure (CKF) on haemodialysis.

BACKGROUND

The literature is consistent with regard to the high prevalence of cognitive impairment among patients with CKF on haemodialysis and its dependence on multidimensional risk factors.

DESIGN

Systematic review and meta-analysis based on Cochrane Handbook and PRISMA.

DATA SOURCES

Electronic searches of the MEDLINE, EMBASE, Cochrane Library databases and major Korean databases were used. Only original research that assessed correlates of cognitive impairment in patients with CKF on haemodialysis and published between 2004-2016 in English or Korean were included.

REVIEW METHODS

Studies were selected according to the PICOS: Population (chronic kidney failure patients with cognitive impairment on haemodialysis); Intervention (not applicable); Comparison (healthy controls or patients with chronic kidney failure on haemodialysis without cognitive impairment); Outcome (cognitive impairment); and Study design (primarily nonexperimental correlational studies and studies with experimental, quasi-experimental, or pre-post cohort designs). Q-test and I² index were used to examine study homogeneity.

RESULTS

A total of 39 studies were finally included. Age, gender, stroke history, difficulties in activities of daily life, haemoglobin levels, pain, sleep difficulties, and depression were found to be significant correlates of cognitive impairment.

CONCLUSIONS

Nurses should be aware that the risk of cognitive impairment in patients with CKF on haemodialysis can be significantly higher for elders, women and in patients with a stroke, greater difficulties in activities of daily living, lower haemoglobin concentrations, higher pain levels, sleep difficulties, or depression.

Analgesic and sedative agents used in the intensive care unit: A review

Pain is a common experience for most patients in the intensive care unit (ICU). In the current study, the advantages and disadvantages of analgesic and sedative drugs used in the ICU are reviewed. An ideal sedative and analgesic agent should have features such as rapid onset of action, rapid recovery after discontinuation, predictability, minimal accumulation of the agent and metabolites in the body, and lack of toxicity. None of the sedative and analgesic agents have all of these desired characteristics; nevertheless, clinicians must be familiar with these classes of drugs to optimize pharmacotherapy and ensure as few side-effects as possible for ICU patients.

The Emergence of Second-Generation Lethal Injection Protocols: A Brief History and Review

The history of capital punishment in the United States is long and controversial. In many cases, lethal injection has brought medical personnel, ethically and professionally charged with preserving life, into the arena of assisting the state in taking life. U.S. Supreme Court decisions, including Baze v. Rees (2008) and Glossip v. Gross (2015), have evaluated and condoned lethal injection protocols. Despite the judicial validation of some midazolam-containing protocols, controversy exists about the level of unconsciousness provided due to the ceiling effects of the drug. Drug shortages, induced in part by manufacturers under pressure by death penalty opponents and governments opposed to capital punishment, have forced states to sometimes use creative means to obtain medications for use in lethal injection, even proposing to allow inmates to supply their own drugs for use in execution. Others have resorted to using compounding pharmacies and enacting tougher execution secrecy laws to protect the identities of those involved in the process. Professional organizations representing health care team members, including nursing, medicine, and pharmacy, among others, have roundly denounced the medicalization of capital punishment. Legal challenges continue to mount at all levels, leading to an uncertain future for lethal injection.

Evidence for Neurotoxicity Due to Morphine or Hydromorphone Use in Renal Impairment: A Systematic Review

BACKGROUND

Opioids are the mainstay of pain control for patients with chronic pain. Often, opioids with reported active metabolites, such as morphine and hydromorphone, are thought to increase the risk of neurotoxicity in renal impairment.

OBJECTIVES

To identify and assess the quality of evidence for neurotoxic effects in patients with renal impairment receiving morphine or hydromorphone.

METHODS

Systematic searches were conducted of the following databases from inception to December 2015: MEDLINE, CINAHL, EMBASE, in addition to hand-searching relevant review articles' citations. Studies were included if they reported neurotoxic effects of either morphine or hydromorphone for chronic or malignant pain in patients with renal impairment. Review articles and case reports were excluded. Narrative review was undertaken. The Grading of Recommendations, Assessment, Development and Evaluation approach was used to assess study quality.

RESULTS

Six original articles, three prospective and three retrospective studies were identified and assessed. No relevant randomized clinical trials were identified.

CONCLUSIONS

Although morphine and hydromorphone use may be associated with neurotoxic effects in patients with renal impairment, current evidence consists of very low-quality studies with conflicting findings. Clinicians may consider using either morphine or hydromorphone in mild-to-moderate renal impairment, while closely monitoring for neurotoxic effects, particularly when used in high doses and for extended duration.

Evolution of Patient-Controlled Analgesia: From Intravenous to Sublingual Treatment

Opioid administration delivered intravenously (IV) by patient-controlled analgesia (PCA) devices has been an important development in addressing insufficient management of acute pain in the postsurgical setting. However, IV PCA has several disadvantages, including operator error, risk of patient exposure to analgesic gaps, IV line patency issues, and risk of catheter-related infection, all of which contribute to the total cost of care. Morphine, the most commonly used opioid in IV PCA, has a relatively slow onset of analgesia, which may leave patients with inadequate initial pain control and at risk of opioid dose-stacking. Sufentanil is an opioid with no major active metabolites and a rapid onset of analgesia. The sufentanil sublingual tablet system (SSTS) with a 20-minute lockout and other safety features is a novel noninvasive PCA system in development for on-demand relief of moderate to severe acute pain in the hospital setting. Data from phase 3 trials of the use of SSTS after elective major open abdominal and orthopedic surgery show that analgesia is rapidly achieved, with a longer mean interdosing interval compared with IV PCA morphine (81 vs 47 minutes) and a high level of patient and nurse satisfaction. These data suggest that SSTS may also aid in the avoidance of some of the pitfalls inherent with IV PCA, which may help reduce hospital costs associated with IV PCA-related issues. This article describes the evolution, benefits, issues, and costs associated with IV PCA and reviews data from preclinical studies of sufentanil through SSTS phase 3 trials.

An Approach to Pain Management in End Stage Renal Disease: Considerations for General Management and Intradialytic Symptoms

The prevalence and severity of symptoms in patients with advanced chronic kidney disease is higher than those of the general population and comparable to those with other chronic and serious medical conditions. Despite the prevalence and severity in this population, symptoms continue to be under-recognized and inadequately managed. The recognition of specific intradialytic pain syndromes such as pain related to arteriovenous access, headaches, muscle cramps or generalized pain by providers may aid in improving patient compliance and quality of life. The approach to pain management in end stage renal disease patients follows that of the general population with specific considerations regarding clearance and potential side effects guiding selection of agents. Overall, evidence is limited regarding the pharmacology of many medications in this population.

Chronic pain and analgesic use in CKD: implications for patient safety

BACKGROUND AND OBJECTIVES

Chronic pain in predialysis CKD is not fully understood. This study examined chronic pain in CKD and its relationship with analgesic usage.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data include baseline visits from 308 patients with CKD enrolled between 2011 and 2013 in the Safe Kidney Care cohort study in Baltimore, Maryland. The Wong-Baker FACES Pain Rating Scale measured chronic pain severity. Analgesic prescriptions and over-the-counter purchases were recorded up to 30 days before visits, and were classified as a drug-related problem (DRP) based on an analgesic's nephrotoxicity and dose appropriateness at participants' eGFR. Participants were sorted by pain frequency and severity and categorized into ordinal groups. Analgesic use and the rate of analgesics with a DRP were reported across pain groups. Multivariate regression determined the factors associated with chronic pain and assessed the relationship between chronic pain and analgesic usage.

RESULTS

There were 187 (60.7%) participants who reported chronic pain. Factors associated with pain severity included arthritis, taking ≥12 medications, and lower physical function. Use of nonsteroidal anti-inflammatory drugs was reported by seven participants (5.8%) with no chronic pain. Mild and severe chronic pain were associated with analgesics with a DRP, with odds ratios of 3.04 (95% confidence interval [95% CI], 1.12 to 8.29) and 5.46 (95% CI, 1.85 to 16.10), respectively. The adjusted rate of analgesics with a DRP per participant increased from the group with none to severe chronic pain, with rates of 0.07 (95% CI, 0.04 to 0.13), 0.12 (95% CI, 0.07 to 0.20) and 0.16 (95% CI, 0.09 to 0.27), respectively.

CONCLUSIONS

Chronic pain is common in CKD with a significant relationship between the severity of pain and both proper and improper analgesic usage. Screening for chronic pain may help in understanding the role of DRPs in the delivery of safe CKD care.

Myoclonus in renal failure: Two cases of gabapentin toxicity

Gabapentin, an AED approved for the adjunctive treatment of partial seizures with/without secondary generalization and for the treatment of postherpetic neuralgia, is frequently used off-label for the treatment of both psychiatric and pain disorders. Since gabapentin is cleared solely by renal excretion, dosing requires consideration of the patient's renal function. Myoclonic activity may occur as a complication of gabapentin toxicity, especially with acute kidney injury or end-stage renal disease. We report 2 cases of myoclonic activity associated with gabapentin toxicity in the setting of renal disease which resolved with discontinuation of gabapentin and treatment with hemodialysis and peritoneal dialysis. As gabapentin has multiple indications and off-label uses, an understanding of myoclonus, neurotoxicity, and renal dosing is important to clinicians in multiple specialties.

Tremors and agitation following low-dose intravenous hydromorphone administration in a patient with kidney dysfunction

OBJECTIVE

To report a case of tremors and agitation associated with the administration of low doses of intravenous hydromorphone in a patient with acute kidney injury in the setting of chronic kidney disease.

CASE SUMMARY

A 91-year-old man was admitted for a left intertrochanteric hip fracture. On hospital days 1 and 2, the patient received hydromorphone 1 mg intravenously for pain. By hospital day 3, the patient had received a total of 3.5 mg of hydromorphone. He then became tremulous and agitated, which worsened as the dose was increased. During hospital day 4, the hydromorphone dosage was increased to 0.5 mg intravenously every 4 hours for what was perceived to be inadequate pain control, manifesting as tremors and agitation. On hospital day 5, hydromorphone, now considered a potential cause of the tremors and agitation, was discontinued. The total amount of hydromorphone administered was 8 mg over 5 days. By hospital day 6, the tremors and agitation had decreased in severity and had resolved by hospital day 7.

DISCUSSION

Previous reports suggest that hydromorphone-induced neurotoxicity is more likely to occur following high doses over extended periods, especially in patients with kidney dysfunction. There is a paucity of evidence suggesting that neurotoxicity can occur following low doses for short periods of time. Morphine-3-glucuronide has neuroexcitatory properties including myoclonus, allodynia, agitation, or tremors. Structural similarities between morphine-3-glucuronide and hydromorphone-3-glucuronide suggest that neuroexcitatory effects with hydromorphone are feasible. The Naranjo probability scale indicated that hydromorphone-induced tremors were possible. Our case is distinct because the patient received low doses of hydromorphone over a short period.

CONCLUSIONS

Neurotoxicity can occur in patients with kidney dysfunction while they receive low doses of intravenous hydromorphone over short periods. Diligent monitoring and reporting of such effects are necessary to better understand risk factors and a mechanism.

Analgesics in patients with hepatic impairment: pharmacology and clinical implications

The physiological changes that accompany hepatic impairment alter drug disposition. Porto-systemic shunting might decrease the first-pass metabolism of a drug and lead to increased oral bioavailability of highly extracted drugs. Distribution can also be altered as a result of impaired production of drug-binding proteins or changes in body composition. Furthermore, the activity and capacity of hepatic drug metabolizing enzymes might be affected to various degrees in patients with chronic liver disease. These changes would result in increased concentrations and reduced plasma clearance of drugs, which is often difficult to predict. The pharmacology of analgesics is also altered in liver disease. Pain management in hepatically impaired patients is challenging owing to a lack of evidence-based guidelines for the use of analgesics in this population. Complications such as bleeding due to antiplatelet activity, gastrointestinal irritation, and renal failure are more likely to occur with nonsteroidal anti-inflammatory drugs in patients with severe hepatic impairment. Thus, this analgesic class should be avoided in this population. The pharmacokinetic parameters of paracetamol (acetaminophen) are altered in patients with severe liver disease, but the short-term use of this drug at reduced doses (2 grams daily) appears to be safe in patients with non-alcoholic liver disease. The disposition of a large number of opioid drugs is affected in the presence of hepatic impairment. Certain opioids such as codeine or tramadol, for instance, rely on hepatic biotransformation to active metabolites. A possible reduction of their analgesic effect would be the expected pharmacodynamic consequence of hepatic impairment. Some opioids, such as pethidine (meperidine), have toxic metabolites. The slower elimination of these metabolites can result in an increased risk of toxicity in patients with liver disease, and these drugs should be avoided in this population. The drug clearance of a number of opioids, such as morphine, oxycodone, tramadol and alfentanil, might be decreased in moderate or severe hepatic impairment. For the highly excreted morphine, hydromorphone and oxycodone, an important increase in bioavailability occurs after oral administration in patients with hepatic impairment. Lower doses and/or longer administration intervals should be used when these opioids are administered to patients with liver disease to avoid the risk of accumulation and the potential increase of adverse effects. Finally, the pharmacokinetics of phenylpiperidine opioids such as fentanyl, sufentanil and remifentanil appear to be unaffected in hepatic disease. All opioid drugs can precipitate or aggravate hepatic encephalopathy in patients with severe liver disease, thus requiring cautious use and careful monitoring.