Opioid Switch Dosing in Chronic Cancer Pain: A Prospective Longitudinal Study

Background: Opioid switching is common, however, conversion tables have limitations. Guidelines suggest postswitch dose reduction, yet, observations show opioid doses may increase postswitch. Objectives: To document the opioid conversion factor postswitch in cancer, and whether pain and adverse effect outcomes differ between switched opioid groups. Design/Setting: This multicenter prospective longitudinal study included people with advanced cancer in Australia. Clinical data (demographics, opioids) and validated instruments (pain, adverse effects) were collected twice, seven days apart. Results: Opioid switch resulted in dose increase (median oral morphine equivalent daily dose 90 mg [interquartile range {IQR} 45-184] to 150 mg [IQR 79-270]), reduced average pain (5.1 [standard deviation {SD} 1.7] to 3.8 [SD 1.6]), and reduced adverse effects. Hydromorphone dose increased 2.5 times (IQR 1.0-3.6) above the original conversion factor used. Conclusions: Opioid switching resulted in overall dose increase, particularly when switching to hydromorphone. Higher preswitch dosing may require higher dose conversion ratios. Dose reduction postswitch risks undertreatment and may not be always appropriate.

Effect of gene variants on opioid dose, pain and adverse effect outcomes in advanced cancer: an explorative study

Aim: Associations between gene variants and opioid net effect are unclear. We conducted an exploratory pharmacogenetic analysis of 35 gene variants and opioid response in advanced cancer. Patients & methods: This multi-center prospective cohort study included clinical data, questionnaires (pain and adverse effects) and DNA (blood). Negative binomial regression and logistic regression were used. Results: Within 54 participants, eight statistically significant associations (p = 0.002-0.038) were observed between gene variants and opioid dose, pain scores or adverse effects, the majority being within the neuroimmune TLR4 pathway (IL1B [rs1143634], IL2 [rs2069762], IL6 [rs1800795], BDNF [rs6265]) and ARRB2 pathway (ARRB2 [rs3786047], DRD2 [rs6275]). Conclusion: Neuroimmune pathway genes may contribute to differences in opioid response in cancer and may be included in future similar studies.

Effectiveness of Opioid Switching in Advanced Cancer Pain: A Prospective Observational Cohort Study

Opioid switching is a common practice of substituting one opioid for another to improve analgesia or adverse effects; however, it has limited evidence. This study aimed to examine the effectiveness of opioid switching in advanced cancer. This multi-center prospective cohort study recruited patients assessed to switch opioids (opioid switch group) or to continue ongoing opioid treatment (control group). Clinical data (demographics, opioids) and validated instruments (pain and adverse effects) were collected over two timepoints seven days apart. Descriptive analyses were utilized. Non-parametric tests were used to determine differences. Fifty-four participants were recruited (23 control group, 31 switch group). At the follow-up, opioid switching reduced pain (worst, average, and now) (p < 0.05), uncontrolled breakthrough pain (3-fold reduction, p = 0.008), and psychological distress (48% to 16%, p < 0.005). The switch group had a ≥25% reduction in the reported frequency of seven moderate-to-severe adverse effects (score ≥ 4), compared to a reduction in only one adverse effect in the control group. The control group experienced no significant pain differences at the follow-up. Opioid switching is effective at reducing pain, adverse effects, and psychological distress in a population with advanced cancer pain, to levels of satisfactory symptom control in most patients within 1 week.

Establishing a Longitudinal Opioid Pharmacogenomic Registry for Cancer Patients: Feasibility and Acceptability

Purpose: Individual genetic variation can affect both pain expression and opioid response. Large cohort datasets are required to validate evidence influencing genomic factors in opioid response. This study examined the feasibility of establishing an opioid pharmacogenomics registry for cancer patients containing longitudinal matched clinical, symptom, pharmacological, and genomic data, with an a priori feasibility target of 50 participants within 12 months. Methods: Consecutive patients with advanced cancer receiving opioids across five palliative care services were recruited. Clinical data (demographics, pain data, adverse effects, medications) and blood (DNA, RNA, pharmacokinetics) were collected over two time points. Patient and clinician qualitative interviews were conducted to assess acceptability. This study was approved by the SVHA Ethics Committee, Melbourne, Australia (HREC 252/18). Results: Enrollment for the registry was deemed feasible. Fifty-eight participants were recruited (median age 63.7, 45% female, 83% complete data), with the most frequent diagnosis being lung cancer (n = 18, 33%) and oxycodone the most frequently prescribed opioid (n = 30, 52%). Qualitative data indicated positive engagement from both patients and clinicians. Conclusion: Establishing a longitudinal opioid pharmacogenomic registry in patients with cancer receiving palliative care is feasible and readily acceptable.

Benefits of Study Participation for Patients with Advanced Cancer Receiving Radiotherapy: A Prospective Observational Study

Background

Patients with advanced cancer and bone metastases may have unmet palliative care (PC) needs that go unnoticed during clinical oncological practice. This observational study describes interventions that were initiated as the patients participated in the Palliative Radiotherapy and Inflammation Study (PRAIS). It was hypothesized that the patients would benefit from study participation due to PC interventions initiated by the study team.

Methods

A retrospective review of patients' electronic records. Patients with advanced cancer and painful bone metastases included in PRAIS were eligible. All patients met with the study team before start of radiotherapy, after completion of Patient Reported Outcome Measures. Interventions initiated by the study team were documented in the patients' electronic records.

Results

A total of 133 patients were reviewed: 63% males, mean (standard deviation [SD]) age 65 (9.6) and mean (SD) Karnofsky performance status (KPS) score 73.2 (9.1). Interventions were initiated in 50% (n = 67) of the patients. Changes in opioid management (69%), treatment of constipation (43%), and nausea (24%) and nutritional advice were most frequent (21%). Patients receiving interventions had lower mean KPS (70 vs. 77 p < 0.001), shorter survival time after study inclusion (median 28 vs. 57.5 weeks p = 0.005) and were more often opioid naïve (12% vs. 39% p < 0.001) than those not receiving interventions by the study team.

Conclusions

Patients with advanced cancer and painful bone metastasis benefited from study participation due to multiple PC interventions initiated by the study team. The findings call for a systematic integration of PC in patients with advanced cancer.

Trial Registration

ClinicalTrials.gov NCT02107664.

Population-based analysis of the impact of trauma on longer-term functional outcomes

BACKGROUND

Functional outcome measures are important as most patients survive trauma. The aim of this study was to describe the long-term impact of trauma within a healthcare region from a social perspective.

METHODS

People active in work or education and admitted to hospitals in Central Norway in the interval 1 June 2007 to 31 May 2010 after sustaining trauma were included in the study. Clinical data were linked to Norwegian national registers of cause of death, sickness and disability benefits, employment and education. Primary outcome measures were receipt of medical benefits and time to return to preinjury work level. Secondary outcome measures were mortality within 30 days or during follow-up.

RESULTS

Some 1191 patients were included in the study, of whom 193 (16·2 per cent) were severely injured (Injury Severity Score greater than 15). Five years after injury, the prevalence of medical benefits was 15·6 per cent among workers with minor injuries, 22·3 per cent in those with moderate injuries and 40·5 per cent among workers with severe injuries. The median time after injury until return to work was 1, 4 and 11 months for patients with minor, moderate and severe injuries respectively. Twelve patients died within 30 days and an additional 17 (1·4 per cent) during follow-up.

CONCLUSION

Patients experiencing minor or major trauma received high levels of medical benefits; however, most recovered within the first year and resumed preinjury work activity. Patients with severe trauma were more likely to receive medical benefits and have a delayed return to work. Registration number: NCT02602405 (http://www.clinicaltrials.gov).

Sleep quality with WHO Step III opioid use for cancer pain

OBJECTIVE

Sleep is often disturbed in patients with advanced cancer. There is limited knowledge about sleep in patients with cancer treated with strong opioids. This study examines sleep quality in patients with advanced cancer who are treated with a WHO Step III opioid for pain.

METHODS

An international, multicentre, cross-sectional study with 604 adult patients with cancer pain using WHO Step III opioids. Sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI) global score (range; 0-21; score >5 indicates poor sleep). PSQI includes sleep quality, sleep latency, sleep duration, sleep efficiency, sleep disturbances, use of sleep medications and daytime dysfunction. Pain and quality of life were assessed by Brief Pain Inventory and European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core30.

RESULTS

The median age was 62 years, 42% were female, mean Karnofsky performance score (KPS) was 62.5 (±14.2) and mean oral daily morphine equivalent dose was 303 mg/24 hours (±543.8 mg). The mean PSQI global score was 8.8 (±4.2) (range 0-20). Seventy-eight per cent were poor sleepers. All PSQI components were affected, and 44% reported trouble sleeping caused by pain. In the multiple regression model, predictors of PSQI global scores were pain intensity, emotional function, constipation, financial difficulties and KPS (adjusted R²=0.21).

CONCLUSION

The majority (78%) of these patients with cancer treated with Step III opioids experienced poor sleep quality. Pain intensity, emotional function, constipation, financial difficulties and KPS predicted poor PSQI global scores. The clinical implication is that healthcare personnel should routinely assess and treat sleep disturbance in patients with advanced cancer disease.

Open Abdomen Treated with Negative Pressure Wound Therapy: Indications, Management and Survival

BACKGROUND

Open abdomen treatment (OAT) is a significant burden for patients and is associated with considerable mortality. The primary aim of this study was to report survival and cause of mortality after OAT. Secondary aims were to evaluate length of stay (LOS) in intensive care unit (ICU) and in hospital, time to abdominal closure and major complications.

METHODS

Retrospective review of prospectively registered patients undergoing OAT between October 2006 and June 2014 at Trondheim University Hospital, Norway.

RESULTS

The 118 patients with OAT had a median age of 63 (20-88) years. OAT indications were abdominal compartment syndrome (ACS) (n = 53), prophylactic (n = 29), abdominal contamination/second look laparotomy (n = 22), necrotizing fasciitis (n = 7), hemorrhage packing (n = 4) and full-thickness wound dehiscence (n = 3). Eight percent were trauma patients. Vacuum-assisted wound closure (VAWC) with mesh-mediated traction (VAWCM) was used in 92 (78 %) patients, the remaining 26 (22 %) had VAWC only. Per-protocol primary fascial closure rate was 84 %. Median time to abdominal closure was 12 days (1-143). LOS in the ICU was 15 (1-89), and in hospital 29 (1-246) days. Eighty-one (68 %) patients survived the hospital stay. Renal failure requiring renal replacement therapy (RRT) (OR 3.9, 95 % CI 1.37-11.11), ACS (OR 3.1, 95 % CI 1.19-8.29) and advanced age (OR 1.045, 95 % CI 1.004-1.088) were independent predictors of mortality in multivariate analysis. The nine patients with an entero-atmospheric fistula (EAF) survived.

CONCLUSION

Two-thirds of the patients treated with OAT survived. Renal failure with RRT, ACS and advanced age were predictors of mortality, whereas EAF was not associated with increased mortality.

Trauma care in a combined rural and urban region: an observational study

BACKGROUND

The available information on trauma care in mixed rural-urban areas with scattered populations is limited. The aim of this study is to describe epidemiology, resource use, transfers and outcomes for trauma care within such an area, prior to implementation of a formal trauma system.

METHODS

A multicentre observational study including potential severely injured patients from June 2007 to May 2010. All patients received by trauma teams at seven acute care hospitals (ACH) and one major trauma centre (MTC) were included. Major trauma was defined as Injury Severity Score (ISS) > 15.

RESULTS

A total of 2323 patients were included. ACH received 1330 patients and delivered definite care to 85% of these. Only 329 (14%) patients were major trauma of which 134 (41%) were initially received at an ACH. Nine per cent of patients were transferred between hospitals. After inter-hospital transfers, 79% of all major trauma patients received definite care at the MTC. Helicopter emergency services admitted 52% of major trauma and performed 68% of inter-hospital transfers from ACH to MTC. Forty-eight patients (2%) died within 30 days.

CONCLUSION

In a region with a dispersed network of hospitals, geographical challenges, and low rate of major trauma cases, efforts should be made to identify patients with major trauma for treatment at a MTC as early as possible. This can be done by implementing triage and transfer guidelines, maintaining competence at ACHs for initial stabilization, and sustaining an organization for effective inter-facility transfers.

The rare Arg181Cys mutation in the μ opioid receptor can abolish opioid responses

BACKGROUND

Genetic variability contributes to variable clinical response to opioids. This study emerged from the observation of three Norwegian patients who showed no or extraordinary poor response to very high doses of opioids. We suspected a genetic defect and applied a 'most likely candidate gene' approach to investigate this possibility.

METHODS

DNA sequencing was used to search for mutations in coding regions of the OPRM1 gene, encoding the μ opioid receptor (hMOR), in one patient. The remaining two patients, and two cohorts comprising 2158 European cancer pain patients and 600 Norwegian healthy volunteers, respectively, were genotyped using a custom-made TaqMan SNP allelic discrimination assay.

RESULTS

DNA sequencing disclosed a homozygous, inactivating Arg181Cys mutation in hMOR in the patient who showed no effects from opioids. The two patients with poor effect from very high doses of opioids were both heterozygous for the mutation. Six heterozygous patients identified among the European cancer patients all used high doses of opioids and/or reported inferior effect on their pain. About one in every 100 Norwegians is heterozygous for the mutation.

CONCLUSIONS

The Arg181Cys mutation occurs at clinically relevant frequencies and produces a signaling dead hMOR which may abolish or significantly reduce opioid effects in affected individuals. Anesthesiologists and practitioners in pain medicine should be aware of this mutation as a possible explanation for inefficiency of opioids and consider genotyping in relevant cases. Individuals homozygous for the mutation may need a highly personalized approach to pain therapy.

Chronic postsurgical pain in patients 5 years after cardiac surgery: A prospective cohort study

BACKGROUND

Chronic postsurgical pain (CPSP) is a common complication after many surgical procedures, including cardiac surgery. The prevalence of CPSP after cardiac surgery ranges from 9.5% to 56%. Most studies on CPSP after cardiac surgery are retrospective and long-term prospective studies are scarce. The aim of this study was to follow CPSP and health-related quality of life (HRQOL) prospectively in a cohort of patients, emphasizing the prevalence from 12 months to 5 years.

METHODS

A total of 534 patients (23% ≥75 years, 67% men) were consecutively included before surgery. Study-specific questionnaires and the Brief Pain Inventory (BPI) were used to measure CPSP at baseline, 12 months and 5-year follow-up. Short-Form Health Survey (SF-36) was used to measure HRQOL.

RESULTS

Among 458 patients who were alive after 5 years, 82% responded (n = 373). The majority, 89.8% (335/373), did not report CPSP, neither 12 months nor 5 years after surgery. Among the 38 patients who reported CPSP after 12 months, 24 (63%) patients did not report CPSP after 5 years. The overall prevalence of CPSP after 5 years was 3.8% (14/373). Patients reporting CPSP and resolved CPSP had lower scores on HRQOL and more pain preoperatively than patients who did not report CPSP.

CONCLUSIONS

The prevalence of CPSP was lower in this study than previously reported. Among the patients reporting CPSP at 12 months, 63% did not report CPSP after 5 years. Hence, the observed decline in CPSP is in line with studies evaluating CPSP in noncardiac surgery.

SIGNIFICANCE

The prevalence of chronic postsurgical pain (CPSP) at 5 years after surgery of 3.8% is lower than previously reported. The majority of patients reporting CPSP after 12 months did not report CPSP after 5 years.

Human Genetic Variability Contributes to Postoperative Morphine Consumption

High interindividual variability in postoperative opioid consumption is related to genetic and environmental factors. We tested the association between morphine consumption, postoperative pain, and single nucleotide polymorphisms (SNPs) within opioid receptor μ 1 (OPRM1), catechol-O-methyltransferase (COMT), uridine diphosphate glucose-glucuronosyltransferase-2B7, and estrogen receptor (ESR1) gene loci to elucidate genetic prediction of opioid consumption. We analyzed 20 SNPs in 201 unrelated Caucasian patients who underwent abdominal surgery and who were receiving postoperative patient-controlled analgesia-administered morphine. Morphine consumption and pain intensity were dependent variables; age and sex were covariates. A haplotype of 7 SNPs in OPRM1 showed significant additive effects on opioid consumption (P = .007); a linear regression model including age and 9 SNPs in ESR1, OPRM1, and COMT explained the highest proportion of variance of morphine consumption (10.7%; P = .001). The minimal model including 3 SNPs in ESR1, OPRM1, and COMT explained 5% of variance (P = .007). We found a significant interaction between rs4680 in COMT and rs4986936 in ESR1 (P = .007) on opioid consumption. SNPs rs677830 and rs540825 of OPRM1 and rs9340799 of ESR1 were nominally associated with pain Numeric Rating Scale scores. Combinations of genetic variants within OPRM1, COMT, and ESR1 better explain variability in morphine consumption than single genetic variants. Our results contribute to the development of genetic markers and statistical models for future diagnostic tools for opioid consumption/efficacy.

PERSPECTIVE

This article presents the efforts dedicated to detect correlations between the genetic polymorphisms and the clinical morphine effect self-administered by patients using a patient-controlled analgesia pump after major surgery. The clinical effect is expressed in terms of morphine consumption and pain scores. REGISTERED ON CLINICALTRIALS.GOV: NCT01233752.

The evidence of neuraxial administration of analgesics for cancer-related pain: a systematic review

BACKGROUND

The present systematic review analysed the existing evidence of analgesic efficacy and side effects of opioids without and with adjuvant analgesics delivered by neuraxial route (epidural and subarachnoid) in adult patients with cancer.

METHODS

Search strategy was elaborated with words related to cancer, pain, neuraxial route, analgesic and side effects. The search was performed in PubMed, EMBASE, and Cochrane for the period until February 2014. Studies were analysed according to methods, results, quality of evidence, and strength of recommendation.

RESULTS

The number of abstracts retrieved was 2147, and 84 articles were selected for full reading. The final selection comprised nine articles regarding randomised controlled trials (RCTs) divided in four groups: neuraxial combinations of opioid and adjuvant analgesic compared with neuraxial administration of opioid alone (n = 4); single neuraxial drug in bolus compared with continuous administration (n = 2); single neuraxial drug compared with neuraxial placebo (n = 1); and neuraxial opioid combined with or without adjuvant analgesic compared with other comprehensive medical management than neuraxial analgesics (n = 2). The RCTs presented clinical and methodological diversity that precluded a meta-analysis. They also presented several limitations, which reduced study internal validity. However, they demonstrated better pain control for all interventions analysed. Side effects were described, but there were few significant differences in favour of the tested interventions.

CONCLUSION

Heterogeneous characteristics and several methodological limitations of the studies resulted in evidence of low quality and a weak recommendation for neuraxial administration of opioids with or without adjuvant analgesics in adult patients with cancer.

Renal function and symptoms/adverse effects in opioid-treated patients with cancer

BACKGROUND

Renal impairment and the risk of toxicity caused by accumulation of opioids and/or active metabolites is an under-investigated issue. This study aimed at analysing if symptoms/adverse effects in opioid-treated patients with cancer were associated with renal function.

METHODS

Cross-sectional multicentre study (European Pharmacogenetic Opioid Study, 2005-2008), in which 1147 adult patients treated exclusively with only one of the most frequently reported opioids (morphine/oxycodone/fentanyl) for at least 3 days were analysed. Fatigue, nausea/vomiting, pain, loss of appetite, constipation and cognitive dysfunction were assessed (EORTC QLQ-C30). Glomerular filtration rate (GFR) was estimated using Cockcroft-Gault (CG), Modification of Diet in Renal Disease (MDRD), and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI Creatinine) equations.

RESULTS

Mild to severe low GFR was observed among 40-54% of patients. CG equation showed that patients with mild and moderate/severe low GFR on morphine treatment had higher odds of having severe constipation (P < 0.01) than patients with normal GFR. In addition, patients with moderate/severe low GFR on morphine treatment were more likely to have loss of appetite (P = 0.04). No other significant associations were found.

CONCLUSION

Only severe constipation and loss of appetite were associated with low GFR in patients treated with morphine. Oxycodone and fentanyl, in relation to the symptoms studied, seem to be safe as used and titrated in routine cancer pain care.

Evidence of peripheral nerve blocks for cancer-related pain: a systematic review

The European Association for Palliative Care has initiated a comprehensive program to achieve an over-all review of the evidence of multiple cancer pain management strategies in order to extend the current guideline for treatment of cancer pain. The present systematic review analyzed the existing evidence of analgesic efficacy for peripheral nerve blocks in adult patients with cancer. A search strategy was elaborated with words related to cancer, pain, peripheral nerve and block. The search was performed in PubMed, EMBASE, and Cochrane for the period until February 2014. The number of abstracts retrieved was 155. No controlled studies were identified. Sixteen papers presented a total of 79 cases. The blocks applied were paravertebral blocks (10 cases), blocks in the head region (2 cases), plexus blocks (13 cases), intercostal blocks (43 cases) and others (11 cases). In general, most cases reported good pain relief and no side effects. The use of peripheral blocks is based upon anecdotal evidence. However, this review only demonstrates the lack of studies, which does not equal a lack of effectiveness.

Prognostic factors in patients with advanced cancer: a comparison of clinicopathological factors and the development of an inflammation-based prognostic system

PURPOSE

In advanced cancer, oncological treatment is influenced by performance status (PS); however, this has limitations. Biomarkers of systemic inflammation may have prognostic value in advanced cancer. The study compares key factors in prognosis (performance status, patient-reported outcomes; PRO) with an inflammation-based score (Glasgow Prognostic Score, mGPS). A new method of prognosis in advanced cancer (combining performance status and mGPS) is tested and then validated.

EXPERIMENTAL DESIGN

Two international biobanks of patients with advanced cancer were analyzed. Key prognostic factors [performance status, PROs (European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C-30), and mGPS (using C-reactive protein and albumin concentrations)] were examined. The relationship between these and survival was examined using Kaplan-Meier and Cox regression methods, in a test sample before independent validation.

RESULTS

Data were available on 1,825 patients (test) and 631 patients (validation). Median survival ranged from 3.2 months (test) to 7.03 months (validation). On multivariate analysis, performance status (HR 1.62-2.77) and mGPS (HR 1.51-2.27) were independently associated with, and were the strongest predictors of survival (P < 0.01). Survival at 3 months varied from 82% (mGPS 0) to 39% (mGPS 2) and from 75% (performance status 0-1) to 14% (performance status 4). When used together, survival ranged from 88% (mGPS 0, PS 0-1) to 10% (mGPS 2, performance status 4), P < 0.001.

CONCLUSION

A systemic inflammation-based score, mGPS, and performance status predict survival in advanced cancer. The mGPS is similar to performance status in terms of prognostic power. Used together, performance status and mGPS act synergistically improving prognostic accuracy. This new method may be of considerable value in the management of patients with advanced cancer.

Is there a genetic cause for cancer cachexia? - a clinical validation study in 1797 patients

BACKGROUND

Cachexia has major impact on cancer patients' morbidity and mortality. Future development of cachexia treatment needs methods for early identification of patients at risk. The aim of the study was to validate nine single-nucleotide polymorphisms (SNPs) previously associated with cachexia, and to explore 182 other candidate SNPs with the potential to be involved in the pathophysiology.

METHOD

A total of 1797 cancer patients, classified as either having severe cachexia, mild cachexia or no cachexia, were genotyped.

RESULTS

After allowing for multiple testing, there was no statistically significant association between any of the SNPs analysed and the cachexia groups. However, consistent with prior reports, two SNPs from the acylpeptide hydrolase (APEH) gene showed suggestive statistical significance (P=0.02; OR, 0.78).

CONCLUSION

This study failed to detect any significant association between any of the SNPs analysed and cachexia; although two SNPs from the APEH gene had a trend towards significance. The APEH gene encodes the enzyme APEH, postulated to be important in the endpoint of the ubiquitin system and thus the breakdown of proteins into free amino acids. In cachexia, there is an extensive breakdown of muscle proteins and an increase in the production of acute phase proteins in the liver.

How to switch from morphine or oxycodone to methadone in cancer patients? a randomised clinical phase II trial

AIM

Opioid switching is a treatment strategy in cancer patients with unacceptable pain and/or adverse effects (AEs). We investigated whether patients switched to methadone by the stop and go (SAG) strategy have lower pain intensity (PI) than the patients switched over three days (3DS), and whether the SAG strategy is as safe as the 3DS strategy.

METHODS

In this prospective, open, parallel-group, multicentre study, 42 cancer patients on morphine or oxycodone were randomised to the SAG or 3DS switching-strategy to methadone. The methadone dose was calculated using a dose-dependent ratio. PI, AEs and serious adverse events (SAEs) were recorded daily for 14 days. Primary outcome was average PI day 3. Secondary outcomes were PI now and AEs day 3 and 14 and number of SAEs.

RESULTS

Twenty one patients were randomised to each group, 16 (SAG) and 19 (3DS) patients received methadone. The mean preswitch morphine doses were 900 mg/day in SAG and 1330 mg/day in 3DS. No differences between groups were found in mean average PI day 3 (mean difference 0.5 (CI -1.2-2.2); SAG 4.1 (CI 2.3-5.9) and 3DS 3.6 (CI 2.9-4.3) or in PI now. The SAG group had more dropouts and three SAEs (two deaths and one severe sedation). No SAEs were observed in the 3DS group.

CONCLUSION

The SAG patients reported a trend of more pain, had significantly more dropouts and three SAEs, which indicate that the SAG strategy should not replace the 3DS when switching from high doses of morphine or oxycodone to methadone.

Content development for EUROPEAN GUIDELINES on the use of opioids for cancer pain: a systematic review and Expert Consensus Study

Workpackage 3.1 (WP 3.1), within the European Palliative Research Collaborative (EPCRC), was aimed at critically revising and updating the European Association for Palliative Care recommendations on cancer pain management. The aim of this paper is to report the results of the first phase in the revision process which consists of a literature review and an expert consensus about the contents to be considered relevant in the development of the new guidelines. A systematic literature search was carried out from 2001 to 2008 through various databases including Medline, Cinahl, Cochrane Database of Systematic Reviews, Embase and Google. Through this process, guideline quality was evaluated, content was compared with EAPC recommendations and a first set of key-points was developed. A modified two-round Delphi method was applied to choose the most relevant topics for future systematic literature reviews. Fourteen guidelines on cancer pain management, published or updated after 2000, were retrieved. A comparison of these guidelines with the EAPC recommendations led to the formulation of 37 key-points, which were submitted to a panel of experts through a Delphi method. Through the responses given by the experts (25 after the first round and 19 after the second) and after a revision by the WP 3.1 local and steering committees, a final list of 22 topics was generated to answer all identified key-points. Each of these topics will be the object of systematic literature reviews. The final version of the "Evidence-based guidelines for the use of opioid analgesics in the treatment of cancer pain: the EAPC recommendations" will be based on the results of the 22 systematic literature reviews.

Cognitive dysfunction and health-related quality of life after a cardiac arrest and therapeutic hypothermia

BACKGROUND

Evidence-based treatment protocols including therapeutic hypothermia have increased hospital survival to over 50% in unconscious out-of-hospital cardiac arrest survivors. In this study we estimated the incidence of cognitive dysfunctions in a group of cardiac arrest survivors with a high functional outcome treated with therapeutic hypothermia. Secondarily, we assessed the cardiac arrest group's level of cognitive performance in each tested cognitive domain and investigated the relationship between cognitive function and age, time since cardiac arrest and health-related quality of life (HRQOL).

METHODS

We included 26 patients 13-28 months after a cardiac arrest. All patients were scored using the Cerebral Performance Category scale (CPC) and Mini-Mental State Examination (MMSE). Twenty-five of the patients were tested for cognitive function using the Cambridge Neuropsychological Test Automated Battery (CANTAB). These patients were tested using four cognitive tests: Motor Screening Test, Delayed Matching to Sample, Stockings of Cambridge and Paired Associate Learning from CANTAB. All patients filled in the Short Form-36 for the assessment of HRQOL.

RESULTS

Thirteen of 25 (52%) patients were classified as having a cognitive dysfunction. Compared with the reference population, there was no difference in the performance in motor function and delayed memory but there were significant differences in executive function and episodic memory. We found no associations between cognitive function and age, time since cardiac arrest or HRQOL.

CONCLUSION

Half of the patients had a cognitive dysfunction with reduced performance on executive function and episodic memory, indicating frontal and temporal lobe affection, respectively. Reduced performance did not affect HRQOL.

Chronic pain after cardiac surgery: a prospective study

BACKGROUND

Chronic pain is a complication of several surgical procedures. The prevalence of chronic pain reported after cardiac surgery varies from 18% to 61%. However, most studies are retrospective, do not use validated instruments for pain measurement or include only pain at the sternum site. The aim of the present study was to assess chronic pain and health-related quality of life (HRQOL) after cardiac surgery.

METHODS

In a prospective, population-based study, we included 534 patients (413 males) and assessed chronic pain and HRQOL before, 6 months after, and 12 months after cardiac surgery. Pain was measured by the Brief Pain Inventory, while HRQOL was measured by the Short-Form 36 (SF-36).

RESULTS

Five hundred and twenty-one patients were alive 12 months after surgery; 462 (89%) and 465 (89%) responded after 6 and 12 months, respectively. Chronic pain was reported by 11% of the patients at both measurements. Younger age was associated with chronic pain [odds ratio 0.7 (95% confidence interval: 0.5-0.9)] at 12 months. Patients with chronic pain reported lower scores on seven of eight SF-36 subscales.

DISCUSSION

In conclusion, we observed a lower prevalence of chronic pain after cardiac surgery than in previous studies. Still, more than one out of 10 patients reported chronic pain after cardiac surgery. Chronic pain appears to affect HRQOL. Thus, given the large number of patients subjected to cardiac surgery, this study confirms that chronic pain after cardiac surgery is an important health care issue.

Classification of pain in cancer patients--a systematic literature review

One of the aims of the European Palliative Care Research Collaborative (EPCRC) is to achieve consensus on a classification system for cancer pain. We performed a systematic literature review to identify existing classification systems and domains/items used to classify cancer patients with pain. In a systematic search in the databases Medline and Embase, covering 1986-2006, 692 hits were obtained. 92 papers were evaluated to address pain classification. Six standardised classification systems were identified; three of them systematically developed and partially validated. Both pain characteristics and patient characteristics relevant for cancer pain classification were included in the classification systems. All but one of the standardised systems aim at predicting treatment response or adequacy of treatment. Several domains and items used to describe cancer pain but not formally described as part of a classification system were also identified and systematized. The existing approaches to pain classification in cancer patients are different, mostly not thoroughly validated, and none is widely applied. An internationally accepted classification system for cancer pain could improve research and cancer pain management. This systematic review suggests a need for developing an international consensus on how to classify pain in cancer patients.

Process of foregoing life-sustaining treatment: a survey among Scandinavian intensivists

BACKGROUND

How ethical issues are dealt with varies considerably depending on the geographic and religious background of individuals. The views of Scandinavian physicians on end-of-life care were studied using a survey. The aim of this study was to clarify the actual processes of foregoing life-sustaining treatment in Scandinavia.

METHODS

A questionnaire was developed and sent to 78 intensive care physicians working in Denmark, Finland, Norway and Sweden.

RESULTS

Forty-four responses were obtained (13 from Denmark, eight from Finland, 12 from Norway and 11 from Sweden); 89% of the respondents were from University Hospitals. Withholding and withdrawing of treatment were practiced in all intensive care units (ICUs) concerned, but written guidelines on end-of-life care existed in only one ICU. End-of-life care is usually arranged in the ICU. Religious support is available in most hospitals during office hours, but lacking in 26% of ICUs outside office hours. Vasoactive medication, renal replacement therapy, and artificial nutrition are among the therapies most likely to be discontinued during withdrawal of life support. Certain types of monitoring and organ support are still continued in many centers during end-of-life care.

CONCLUSION

Local written guidelines on end-of-life care are scarce in Scandinavian ICUs, which may explain the observed variability in the practices. Development of guidelines and monitoring how these instructions are carried out may help to improve the quality of care of dying ICU patients.

A controlled comparison between single doses of intravenous and intramuscular morphine with respect to analgesic effects and patient safety

BACKGROUND AND AIM OF INVESTIGATION: Intramuscular (IM) administration has been considered to be safer than intravenous (IV) for opioids on wards, but a comparative knowledge of patient safety and analgesic potency following a single dose of IV and IM administration is lacking. This study was carried out to compare patient safety and analgesic efficacy of a single and high dose of morphine given IM or IV for post-operative pain management.

MATERIALS AND METHODS

Thirty-eight patients with post-operative pain following hip replacement surgery were given IM or IV morphine 10 mg at a specified pain level. The study was randomized and double blinded. Time to onset of analgesic effect (11-point numeric rating scale), respiratory function (p(a)CO2, p(a)O2, and respiratory rate), level of sedation (5-point verbal rating scale), and hemodynamic function were recorded.

RESULTS

In the IV group there was a slight but significant increase in p(a)CO2 after 5, 10, and 15 min compared with the IM group (5.2 vs. 4.8, 5.4, vs. 5.0 and 5.5 vs. 5.1 kPa, respectively). The IV group had a significantly faster onset of analgesic effect than the IM group (5 vs. 20 min). Between 5 and 25 min after morphine administration, pain status in the IV group was significantly improved compared with the IM group. Patients in the IV group were slightly more sedated than the IM group 5 and 10 min after morphine.

CONCLUSION

A 10 mg bolus dose of IV morphine given to patients with moderate pain after surgery does not cause severe respiratory depression, but provides more rapid and better initial analgesia than 10 mg given IM. IV morphine even at a dose as high as 10 mg IV is well tolerated if there is a certain level of pain at its administration. The safety of IV morphine on the general ward needs to be further explored in adequately controlled studies.

Variable response to opioid treatment: any genetic predictors within sight?

The aim of this literature review is to summarize and discuss the available evidence for a relationship between polymorphisms in human genes and variability in opioid analgesia and side effects among patients treated for moderate or severe pain. The evidence supporting a role of certain alleles, genotypes or haplotypes in modulation of opioid analgesia is derived from a limited number of studies, a limited number of genes and a limited number of opioids. Although several interesting candidates have emerged as potentially relevant factors, only for one polymorphism, the prevalent 118A>G of the micro-opioid receptor, the accumulated evidence is sufficient to suggest a clinically relevant effect for an opioid used for moderate or severe pain. Still the data are valid only at the group level and cannot be used to predict treatment outcome in individual patients. Only a few of the symptoms often seen as opioid adverse effects in palliative care, such as nausea, vomiting, constipation and sedation, have been associated with genetic variants in various genes, but the results have been based on case reports, healthy volunteers or post-operative patients. So far, there is no clear evidence that genetic markers can be used to predict opioid efficacy or adverse effects in palliative care patients. This reflects the general lack of studies performed in the context of palliative care, the lack of sufficiently scaled studies and the lack of international standards for the assessment of subjective symptoms.

Severe head injury: control of physiological variables, organ failure and complications in the intensive care unit

BACKGROUND

In patients with severe head injury, control of physiological variables is important to avoid intracranial hypertension and secondary injury to the brain. The aims of this retrospective study were to evaluate deviations of physiological variables and the incidence of extracranial complications in patients with severe head injury. We also studied if these deviations could be related to outcome.

PATIENTS AND METHODS

One hundred and thirty-three patients were included during a 5-year period (1998-2002). Deviations from treatment goals for the following physiological variables were studied: blood pressure, haemoglobin, blood sugar, serum sodium, serum albumin and temperature. Extra cerebral organ complications were also recorded as well as outcome at 6 months.

RESULTS

The median age was 32 years (range; 1-88 years). Median Glasgow Coma Scale (GCS) before intubation was 6 (range; 3-14). The frequencies of severe deviations from the desired values of the physiological variables for at least one treatment day were: hypotensive episodes (systolic BP < 90 mmHg) - 20%, anaemia (hgb < 8 g/dL) - 22%, blood glucose > 10 mmol/l - 26%, serum sodium concentration < 130 mmol/l - 10%, serum albumin < 25 g/l(-1)- 31% and hyperthermia > 39 degrees C - 24%. Pneumonia was diagnosed in 71% and Acute Lung Injury (ALI)/Adult Respiratory Distress Syndrome (ARDS) in 26% of the patients. Other complications such as severe sepsis (6%), renal failure (1.5%), a coagulation disorder (6%) and liver failure (one patient) were infrequent. Age, GCS, hypotension during the first day of treatment, elevated blood sugar and low albumin predicted an unfavourable outcome.

CONCLUSIONS

Deviations of key physiological variables and pulmonary complications were frequent in patients suffering from severe head injury. During intensive care treatment, hypotension, elevated blood sugar and hypoalbuminemia are possible independent predictors of an unfavourable outcome.

Serum and cerebrospinal fluid morphine pharmacokinetics after single doses of intravenous and intramuscular morphine after hip replacement surgery

AIM

To compare the time course of morphine and metabolite concentrations in serum and cerebrospinal fluid (CSF) after intravenous and intramuscular administration after surgery.

METHODS

This was a randomized double-blind, double-dummy study in patients who had undergone hip replacement surgery. Morphine (M, 10 mg) was administered intravenously (IV) or intramuscularly (IM). Arterial blood and CSF samples (from a spinal catheter) were drawn simultaneously at 10, 30, 60, and 120 min after administration. Morphine and metabolites [morphine-3-glucuronide (M-3-G), morphine-6-glucuronide (M-6-G), and normorphine (NM)] were determined by a validated liquid chromatography-tandem mass spectrometry method.

RESULTS

Thirty-eight patients were included: 13 men and 25 women, 20 in the IV, 18 in the IM group. Serum concentrations of M after 10 min were consistently higher after IM than IV, concentrations of M-3-G and M-6-G after IM surpassed those of IV after 45 min. NM was not found. None of the metabolites was found in CSF. CSF morphine concentrations and CSF/serum concentration ratios were consistently higher after IV compared to IM. The mean AUC(CSF)/AUC(serum) (0-120 min) concentration ratios were 0.18 and 0.09 after IV and IM, respectively.

CONCLUSIONS

The uptake of morphine to the CSF was consistently higher after IV administration than after IM already after 10 min. The higher CSF concentration may be caused by an initially higher morphine blood/CSF gradient following IV morphine injection. The pharmacokinetic findings are compatible with a more rapid and extensive initial effect of IV morphine compared with IM.

Ethical issues in intensive care--a survey among Scandinavian intensivists

BACKGROUND

The general principles of medical ethics are universally accepted. In practice, however, there is variation on how these principles are interpreted by people with different cultural backgrounds. The aim of this study was to document the views of Scandinavian intensive care physicians on intensive care unit (ICU) admission, triage, withholding and withdrawal of intensive care, and communication between the patient, the family and the ICU team.

METHODS

A questionnaire was developed and sent to 84 intensive care physicians working in Denmark, Finland, Sweden and Norway.

RESULTS

The response rate was 61%. In general, the responses were in agreement with published guidelines. Nevertheless, there was considerable variation on what factors are taken into account when priority decisions are made. In addition, the views on the content of information provided to the family varied. A majority of 80% reported priority decisions being made on a regular basis. Less than one-half of the respondents had correct knowledge regarding the existence or lack of national guidelines on intensive care ethics. Only 8% of the respondents were aware of guidelines published by the Society of Critical Care Medicine.

CONCLUSION

Variation in priority determinants between individual physicians may compromise justice in health care. An effort should be made to discuss and adopt mutual principles. In addition, the quality of information available to the patients' representatives deserves our attention. The results of this study could be used as a basis for discussion when guidelines on the ethical aspects of intensive care are developed and reviewed.

Genetic variability and clinical efficacy of morphine

The individual variability of opioid pharmacology suggests that the patients' genetic disposition influences the response to opioids. Given the complexity of morphine pharmacology, variability may be caused by several genes. We review data which shows that variability in genes coding the enzyme metabolizing morphine (UGT2B7 gene), mu-opioid receptors (OPRM gene) and blood-brain barrier (BBB) transport of morphine by multidrug resistance transporters (MDR1 gene) influences the clinical efficacy of morphine. Furthermore, variability in an enzyme degrading catecholamines (COMT gene) alters the efficacy of morphine demonstrating that genetic variability in non-opioid systems may indirectly influence the clinical efficacy from morphine. Thus, results obtained so far strongly argue that opioid efficacy is partly related to inborn properties caused by genetic variability.

The 118 A > G polymorphism in the human mu-opioid receptor gene may increase morphine requirements in patients with pain caused by malignant disease

BACKGROUND

Dispositions for genes encoding opioid receptors may explain some variability in morphine efficacy. Experimental studies show that morphine and morphine-6-glucuronide are less effective in individuals carrying variant alleles caused by the 118 A > G polymorphism in the mu-opioid receptor gene (OPRM1). The purpose of the study was to investigate whether this and other genetic polymorphisms in OPRM1 influence the efficacy of morphine in cancer pain patients.

METHODS

We screened 207 cancer pain patients on oral morphine treatment for four frequent OPRM1 gene polymorphisms. The polymorphisms were the -172 G > T polymorphism in the 5'untranslated region of exon 1, the 118 A > G polymorphism in exon 1, and the IVS2 + 31 G > A and IVS2 + 691 G > C polymorphisms, both in intron 2. Ninety-nine patients with adequately controlled pain were included in an analysis comparing morphine doses and serum concentrations of morphine and morphine metabolites in the different genotypes for the OPRM1 polymorphisms.

RESULTS

No differences related to the -172 G > T, the IVS2 + 31 G > A and the IVS2 + 691 G > C polymorphisms were observed. Patients homozygous for the variant G allele of the 118 A > G polymorphism (n = 4) needed more morphine to achieve pain control, compared to heterozygous (n = 17) and homozygous wild-type (n = 78) individuals. This difference was not explained by other factors such as duration of morphine treatment, performance status, time since diagnosis, time until death, or adverse symptoms.

CONCLUSION

Patients homozygous for the 118 G allele of the mu-opioid receptor need higher morphine doses to achieve pain control. Thus, genetic variation at the gene encoding the mu-opioid receptor contributes to variability in patients' responses to morphine.

Sequence variations in the UDP-glucuronosyltransferase 2B7 (UGT2B7) gene: identification of 10 novel single nucleotide polymorphisms (SNPs) and analysis of their relevance to morphine glucuronidation in cancer patients

We have screened a cohort of 239 Norwegian cancer patients for sequence variation in the coding and regulatory regions of the UDP-glucuronosyltransferase 2B7 gene (UGT2B7) and analyzed the impact of gene variants on morphine glucuronidation in vivo. In all, 12 single nucleotide polymorphisms (SNPs) were identified, 10 of which have not been previously described. Only one SNP causes a change in amino acid sequence (H268Y). Seven UGT2B7 genotypes were observed and three main haplotypes predicted. There was no correlation between UGT2B7 genotype or haplotype and morphine glucuronide to morphine serum ratios among 175 patients who received chronic oral morphine therapy, and who had normal renal and hepatic function. The apparent lack of functional polymorphisms fits well with the near unimodal, but broad, distributions of the ratios (morphine 3-glucuronide/morphine: 6.4-309.2; morphine 6-glucuronide/morphine: 0.5-72.8). Our results suggest that factors other than UGT2B7 polymorphism may be more deciding for the variability in morphine glucuronide to morphine serum ratios.

Influences on serum concentrations of morphine, M6G and M3G during routine clinical drug monitoring: a prospective survey in 300 adult cancer patients

BACKGROUND

In order to make treatment decisions physicians should have knowledge about the relations between patient characteristics and drug disposition. Dose, route of administration, gender, age and renal function are reported to influence the serum concentrations of morphine, morphine-6-glucurnide (M6G) and morphine-3-glucuronide (M3G) during chronic treatment of cancer pain. These factors, however, are not evaluated in studies with a sample size sufficient to explore predictive factors.

METHODS

Three hundred consecutive morphine users admitted because of a malignant disease were recruited. The relations of serum concentrations of morphine, M6G and M3G to patient characteristics (gender, age, weight, renal function, liver function, dose, route of administration) were explored, and regression analysis performed to investigate whether these characteristics predicted serum concentrations obtained during routine clinical drug monitoring.

RESULTS

Morphine dose was associated with serum concentrations of morphine (r = 0.69), M6G (r = 0.76) and M3G (r = 0.76). Oral morphine resulted in higher dose-adjusted M6G and M3G serum concentrations compared with s.c. morphine. Creatinine serum concentrations correlated with serum concentrations of M6G and M3G. Dose and route of administration predicted morphine serum concentrations, while dose and renal function predicted M6G and M3G serum concentrations. Age was an additional factor predicting M3G concentrations. Dose was the only factor that explained a clinically significant part of the observed variability.

CONCLUSION

Patient characteristics predict only minor parts of the variability of morphine, M3G and M6G serum concentrations observed during routine clinical drug-monitoring in cancer patients.

Immediate- or sustained-release morphine for dose finding during start of morphine to cancer patients: a randomized, double-blind trial

A titration procedure using immediate-release morphine given 4-hourly is recommended during start of oral morphine for cancer pain. This recommendation is not based on evidence from controlled studies, and many physicians start morphine treatment with controlled-release morphine. We included 40 patients with malignant disease and pain despite treatment with opioids for mild to moderate pain in a randomized, double-blind, double-dummy, parallel-group study comparing titration with immediate-release morphine given 4-hourly with titration with sustained-release morphine given once daily. The primary end point was the time needed to achieve adequate pain relief Secondary end points were other symptoms (nausea, tiredness, lack of sleep, vertigo, appetite and constipation), health related quality of life and patient satisfaction. The mean times needed for titration were 2.1 (95% CI; 1.4-2.7) days using immediate-release morphine and 1.7 (95% CI; 1.1-2.3) days using sustained-release morphine. Patients titrated with immediate-release reported statistically significant more tiredness at the end of titration. We observed no other differences in adverse effects or health related quality of life functions between the two treatments. Similar global satisfactions with the morphine treatments were reported. In conclusion, a simplified titration using sustained-release morphine once daily is equally effective as immediate-release morphine given 4-hourly.

Long-term treatment with ketamine in a 12-year-old girl with severe neuropathic pain caused by a cervical spinal tumor

A 12-year-old girl presented with head and neck pain, myoclonic movements, and decreased strength in all extremities caused by a cervical spinal tumor (glioblastoma multiforme). A partial resection of the tumor was performed. Three weeks later, she had superficial pain distributed in all dermatomes below her cervical medullary lesion. Touch (e.g., gentle hugs from relatives) and movements elicited paroxysm of intense pain. The pain was not relieved by increased doses of morphine. A test dose of ketamine (7.5 mg intravenous) provided an abrupt decrease in pain intensity, and continuous infusions of subcutaneous morphine and intravenous ketamine were started. Benzodiazepines were administered to avoid psychotomimetic effects from ketamine and to diminish myoclonic movements. The doses of analgesics and benzodiazepines were increasingly titrated (subcutaneous morphine 163-750 mg/24 hr, intravenous ketamine 36-410 mg/24 hr, subcutaneous midazolam 5-20 mg/24 hr, and intravenous diazepam 11.5-122.5 mg/24 hr) until her death 67 days after start of ketamine. She remained awake until the last day before her death. For the last 29 days of life, the pain treatment regimen was successfully continued in her home (400-km distance from the hospital). In conclusion, this case demonstrates that ketamine treatment may be effective in children with severe neuropathic pain not responsive to other analgesics. This patient also demonstrates the feasibility of long-term ketamine treatment in pediatric oncology and that such treatment can be administered in a home care setting.

Circadian distribution of oral opioid consumption in cancer patients

Diurnal variations are reported in pain perception, potency of placebo and in the pharmacokinetics of morphine. It is not established if such diurnal variation should be reflected in the routine prescription of analgesic drugs to cancer patients. One approach for investigating this question is to study the circadian rhythm of patients' requests for analgesics. We included 40 patients with malignant disease and intolerable pain despite treatment with weak opioids. Weak opioids were stopped and the patients' pain treatment was restricted for the next 2 days to strong oral opioids (ketobemidone) given on an as-needed basis. The number and times of all ketobemidone administrations were recorded. No significant diurnal variation in use of ketobemidone was observed. A descriptive curve that interpolates between successive observations displayed only slight circadian fluctuations of opioid consumption. Thus, the data reported in this paper does not support the necessity of considering chronopharmacological factors in the routine prescription of oral opioids.

Pain intensity and side effects during titration of morphine to cancer patients using a fixed schedule dose escalation

BACKGROUND

Considerable dose variations and frequent initial side effects have been postulated during start of morphine treatment to patients with pain caused by malignant disease. However, to our knowledge, only one previous study has reported effective doses in morphine naive cancer patients and no prospective evaluation has compared symptoms before with symptoms during morphine titration.

METHODS

We recruited 40 cancer patients with uncontrolled pain despite receiving codeine or dextropropoxyphen. Baseline data were obtained for two days before start of morphine titration using a fixed scheduled escalation of immediate-release (IR) morphine. When a stable morphine dose was achieved, IR morphine was replaced with slow-release (SR) morphine in equivalent doses. Intensity of pain and side effects were assessed daily. The daily consumption of morphine, rescue analgesics and rescue antiemetics were registered.

RESULTS

The mean titration time to achieve adequate analgesia was 2.3 days (range: 1-6) using a mean daily morphine dose of 97 mg (range: 60-180). Nausea was unaltered after start with morphine but an increased incidence of vomiting occurred (premorphine period 5%, IR morphine period 29%). Transient sedation delayed dose increment in 9 of the 40 patients but mean sedation scores were unaltered. Constipation scores increased while other side effect scores were unaltered. Eighty-two percent of the patients were satisfied or very satisfied with the pain treatment during introduction of morphine.

CONCLUSION

In cancer patients with uncontrolled pain on weak opioids, successful titration of morphine is achieved fast, with a three-fold morphine dose variation and with little increase in side effects.

Effects on cancer patients' health-related quality of life after the start of morphine therapy

To investigate the effects of morphine on cancer patients' health-related quality of life (HRQL), we prospectively studied 40 cancer patients with moderate or severe pain despite treatment with "weak" opioids. The patients were titrated to pain relief using immediate-release (IR) morphine and then switched to slow-release (SR) morphine in the same daily dosages. HRQL was measured by the European Organization for Research and Treatment of Cancer core quality-of-life questionnaire (EORTC QLQ-C30) before the start of morphine (baseline), after stabilization with IR-morphine, and 3 days after start of SR-morphine. The mean titrated daily morphine dosage was 97 mg (range, 60-180). The EORTC QLQ-C30 global health score increased after IR morphine titration (baseline score 40, IR morphine period score 49), but a significant difference from baseline did not persist during the SR morphine period (score 44). The other functional HRQL scores showed no significant fluctuations. After start of IR morphine, two of the HRQL symptom scores increased, nausea/vomiting and constipation, but these changes also did not persist during the SR morphine period. Intensity of pain was associated with a lower level of function and higher intensity of symptoms, but only with relatively small (not higher than 0.44) correlation coefficients. Compared to normative data from the general population, physical function, role function, social function, and global health were impaired in the study patients. The patients also suffered more fatigue, pain, nausea/vomiting, appetite loss, and constipation. In conclusion, in cancer patients with reduced HRQL, the start of morphine therapy had no major influence on aspects of HRQL other than pain.

Start of oral morphine to cancer patients: effective serum morphine concentrations and contribution from morphine-6-glucuronide to the analgesia produced by morphine

OBJECTIVE

To investigate the serum concentrations of morphine, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) and the relationships between serum concentrations and clinical effects associated with start of morphine treatment in cancer patients.

METHODS

Forty patients with malignant disease and intolerable pain on weak opioids (codeine/dextropropoxyphen) were included. After a wash-out period, titration with immediate-release (IR) morphine was started. When a stable dose was achieved, the morphine treatment was changed to slow-release (SR) morphine in equivalent daily dosages. Clinical data and serum concentrations of morphine, M3G and M6G were obtained at the end of the IR and SR morphine treatment periods.

RESULTS

The mean trough serum morphine concentration associated with pain relief was 66 nmol/l. The corresponding mean concentrations of M6G and M3G were 257 nmol/l and 1943 nmol/l, respectively. Morphine serum trough concentrations showed a 33-fold variation. Seventy percent of the variation was predicted in a model including age, daily morphine dose and M6G/morphine ratio as independent variables. No associations were observed between side effects and serum concentrations of morphine and its metabolites.

CONCLUSION

In this study, a mean serum trough morphine concentration of 66 nmol/l was associated with satisfactory pain relief when disease progression required an increase in intensity of pain therapy from step II to step III in the World Health Organization pain ladder. An increased ratio of M6G to morphine serum concentrations predicted lower effective serum morphine concentrations at the time of satisfactory pain relief. This observation supports that M6G contributes to the pain control produced by oral morphine in patients with pain caused by malignant disease.

Relief of postural post dural puncture headache by an epidural blood patch 12 months after dural puncture

A 20-year-old previously healthy male presented at the pain clinic with chronic headache of about one year duration. Clinical examination revealed no pathological manifestations. During the consultation the patient was drinking Coca-Cola. On direct questioning he told that drinking Coca-Cola gave partial relief from the headache, and that the headache started after he had received two spinal anaesthetics for treatment of a lower leg fracture. Postural post dural puncture headache was now suspected and an epidural blood patch performed. Despite an interval of nearly 12 months since the dural punctures, a single epidural blood patch completely relieved the headache. This case history demonstrates that an epidural blood patch should be tried if a chronic post dural puncture headache is suspected.