Postoperative analgesia and functional recovery after total-knee replacement: comparison of a continuous posterior lumbar plexus (psoas compartment) block, a continuous femoral nerve block, and the combination of a continuous femoral and sciatic nerve block

BACKGROUND AND OBJECTIVES: Continuous femoral nerve block is a well-accepted technique for regional analgesia after total-knee replacement. However, many patients still experience considerable pain at the popliteal space and at the medial aspect of the knee. The goal of this study is to evaluate whether a psoas compartment catheter provides better postoperative analgesia than a femoral nerve catheter does and whether it is as effective as the combination of a femoral and a sciatic nerve catheter and, thus, improves functional outcome. METHODS: Ninety patients who underwent total-knee replacement under standardized general anesthesia participated in this prospective randomized study. Group FEM received a continuous femoral nerve block, group FEM/SCI received a combination of a femoral and a sciatic continuous nerve block, and group PSOAS received a continuous psoas compartment block. Patient-controlled analgesia with piritramide was available for 48 hours. Maximal bending and extending of the knee and walking distance was assessed during the first 7 days. A standardized telephone survey was conducted after 9 to 12 months to evaluate residual pain and functional outcome. RESULTS: Postoperative opioid consumption during 48 hours was significantly less in the FEM/SCI group (median: 18 mg; 25th/75th percentile: 6/40) compared with the FEM group (49 mg; 25/66) and the PSOAS group (44 mg; 30/62) (P =.002). Postoperative pain scores were not different, and no differences occurred with respect to short-term or long-term functional outcome. CONCLUSION: The FEM/SCI catheter is superior to FEM and PSOAS catheter with respect to reduced analgesic requirements after total-knee replacement, but functional outcome does not differ with those 3 continuous regional analgesia techniques.     

Polymorphisme génétique et interactions médicamenteuses : leur importance dans le traitement de la douleur

OBJECTIVES: To evaluate the impact of certain genetic polymorphisms on variable responses to analgesics SOURCES: Systematic review, by means of a structured computerized search in the Medline database (1966-2004). KEY WORDS: pharmacogenetics, polymorphism, cytochrome P450 (CYP), glycoprotein P (P-gp), pain, antalgics, opiates, morphine, codeine, tramadol, non-steroidal anti-inflammatory drugs (NSAID). Articles in English and French were selected. References in relevant articles were also retrieved. MAIN FINDINGS: Most analgesics are metabolized by CYP isoenzymes subject to genetic polymorphism. NSAIDs are metabolized by CYP2C9; opioids described as "weak" (codeine, tramadol), anti-depressants and dextromethorphan are metabolized by CYP2D6 and some "potent" opioids (buprenorphine, methadone or fentanyl) by CYP3A4/5. After the usual doses have been administered, drug toxicity or, on the contrary, therapeutic ineffectiveness may occur, depending on polymorphism and the substance. Drug interactions mimicking genetic defects because of the existence of CYP inhibitors and inducers, also contribute to the variable response to analgesics.Some opioids are substrates of P-gp, a transmembrane transporter also subject to genetic polymorphism. However, P-gp could only play a minor modulating role in man on the central effects of morphine, methadone and fentanyl. CONCLUSION: In the near future, pharmacogenetics should enable us to optimize therapeutics by individualizing our approach to analgesic drugs and making numerous analgesics safer and more effective. The clinical usefulness of these individualized approaches will have to be demonstrated by appropriate pharmacoeconomic studies and analyses.     

Risk factors for cartilage infections of the ear

BACKGROUND: Investigation and case-control study to identify risk factors in a large outbreak in 2003 of auricular chondritis associated with piercing. METHODS: Epidemiologic, environmental, and laboratory (pulsed-field gel electrophoresis) investigation, and case-control study. Telephone interviews were conducted for 15 cases and 61 controls. Odds ratios were determined for risks of infection. RESULTS: Of 15 confirmed cases, nine (60%) were hospitalized (median duration 4.4 days) and treated with intravenous/oral antibiotics. Cases required surgical treatment and multiple antibiotics. Risk factors for infection included piercing location and the use of a contaminated aftercare solution. Pseudomonas aeruginosa isolates, nine from patients and four from the aftercare solution, were indistinguishable by pulsed-field gel electrophoresis; one from the sink at the facility differed by two bands. CONCLUSIONS: This study demonstrates the serious consequences of cartilage piercing, identifies specific risk factors for infection, and suggests the importance of implementation and assurance of safe procedures.     

Empowering youth for tobacco control

PURPOSE: To investigate common youth group activities and how they relate to young people's attitudes of empowerment around tobacco control. DESIGN: A mailed survey was administered to 940 Minnesota youth involved in locally organized tobacco prevention groups. By multivariate linear regression, participation in eight tobacco-related activities and selected personal characteristics were examined in relation to youths'perceived influence on youth smoking. RESULTS: Two activities--developing materials with antismoking messages and taking action to change school smoking policies--were associated with significantly higher perceived influence scores for the youth involved (p < .05). Youth in groups who had worked to raise awareness of how the tobacco industry targets teens also had significantly higher influence scores (p < .001). Associated personal factors included high involvement in extracurricular activities (p < .001), having never experimented with smoking (p < .01), leadership experience (p < .001), and being white (p < .01). DISCUSSION: Some youth group activities and strategies may be particularly effective at instilling attitudes of empowerment for tobacco control among youth.     

Are factor analytical techniques used appropriately in the validation of health status questionnaires? A systematic review on the quality of factor analysis of the SF-36

Factor analysis is widely used to evaluate whether questionnaire items can be grouped into clusters representing different dimensions of the construct under study. This review focuses on the appropriate use of factor analysis. The Medical Outcomes Study Short Form-36 (SF-36) is used as an example. Articles were systematically searched and assessed according to a number of criteria for appropriate use and reporting. Twenty-eight studies were identified: exploratory factor analysis was performed in 22 studies, confirmatory factor analysis was performed in five studies and in one study both were performed. Substantial shortcomings were found in the reporting and justification of the methods applied. In 15 of the 23 studies in which exploratory factor analysis was performed, confirmatory factor analysis would have been more appropriate. Cross-validation was rarely performed. Presentation of the results and conclusions was often incomplete. Some of our results are specific for the SF-36, but the finding that both the application and the reporting of factor analysis leaves much room for improvement probably applies to other health status questionnaires as well. Optimal reporting and justification of methods is crucial for correct interpretation of the results and verification of the conclusions. Our list of criteria may be useful for journal editors, reviewers and researchers who have to assess publications in which factor analysis is applied.     

The impact of non-traumatic hip and knee disorders on health-related quality of life as measured with the SF-36 or SF-12. A systematic review

Objectives: The purpose of this review is to summarize the available evidence on the impact of non-traumatic hip or knee disorders on health-related quality of life (HRQL), as measured with the Short Form 36 Health Survey (SF-36) or Short Form 12 Health Survey (SF-12), by comparing this with data from reference populations. Methods: Studies were identified by an electronic search of the MEDLINE, PsychInfo and Cinahl databases. Studies with the following features were included: study population included patients with non-traumatic hip or knee disorders, the SF-36 or SF-12 was used as an outcome measure and mean scores on these HRQL measures were presented. Using mean HRQL scores from the selected studies and scores from reference populations, z-scores were computed. Pooled estimates were computed for subgroups of studies with similar patients in similar settings. Results: A total of 40 studies met the inclusion criteria. Patients with non-traumatic hip and knee disorders scored up to 2.5 standard deviations (SDs) below reference population values, especially on the physical aspects of HRQL. Social and mental aspects were up to 1 SD below reference population values, especially in patients in clinical settings. Conclusions: The impact of non-traumatic hip or knee disorders on HRQL is substantial, especially on the physical aspects of HRQL.     

N-terminal pro-brain natriuretic peptide, C-reactive protein, and urinary albumin levels as predictors of mortality and cardiovascular events in older adults

Context  B-type natriuretic peptides have been shown to predict cardiovascular disease in apparently healthy individuals but their predictive ability for mortality and future cardiovascular events compared with C-reactive protein (CRP) and urinary albumin/creatinine ratio is unknown. Objective  To assess the prognostic value of the N-amino terminal fragment of the prohormone brain natriuretic peptide (NT-proBNP) vs CRP and urinary albumin/creatinine ratio in an older adult population. Design, Setting, and Participants  A population-based prospective study of 764 participants aged 50 to 89 years from a community in Copenhagen, Denmark, in which 658 participants provided blood and urinary samples and were examined between September 1, 1998, and January 24, 2000. Of these participants, 626 without heart or renal failure were enrolled. A subgroup of 537 had no history of cardiovascular disease at baseline. During 5 years of follow-up (to December 31, 2003), 94 participants died and 65 developed a first major cardiovascular event. Main Outcome Measures  Risk of mortality and first major cardiovascular event by baseline levels of NT-proBNP, CRP, and urinary albumin/creatinine ratio levels. Results  After adjustment for the cardiovascular risk factors of age, sex, smoking, diabetes mellitus, hypertension or ischemic heart disease, total cholesterol, and serum creatinine, the hazard ratio (HR) of mortality for values above the 80th percentile of NT-proBNP was 1.96 (95% confidence interval [CI], 1.21-3.19); for CRP, 1.46 (95% CI, 0.89-2.24); and for urinary albumin/creatinine ratio, 1.88 (95% CI, 1.18-2.98). Additional adjustment for left ventricular systolic dysfunction did not markedly attenuate the predictive value of NT-proBNP (HR, 1.82; 95% CI, 1.11-2.98). The absolute unadjusted increase in mortality risk for participants with values above the 80th percentile vs equal to or below the 80th percentile was 24.5% for NT-proBNP, 7.8% for CRP, and 19.5% for urinary albumin/creatinine ratio. The NT-proBNP levels were associated with first major cardiovascular events (nonfatal myocardial infarction, fatal coronary heart disease, unstable angina, heart failure, stroke, and transient ischemic attack) with an adjusted HR of 3.24 (95% CI, 1.80-5.79) vs 1.02 (95% CI, 0.56-1.85) for CRP and 2.32 (95% CI, 1.33-4.05) for urinary albumin/creatinine ratio when comparing participants with values above the 80th percentile with those with values equal to or below the 80th percentile. Conclusions  Measurements of NT-proBNP provide prognostic information of mortality and first major cardiovascular events beyond traditional risk factors. NT-proBNP was a stronger risk biomarker for cardiovascular disease and death than CRP was in nonhospitalized individuals aged 50 to 89 years.      

Obesity in older adults: technical review and position statement of the American Society for Nutrition and NAASO, The Obesity Society

Obesity causes serious medical complications and impairs quality of life. Moreover, in older persons, obesity can exacerbate the age-related decline in physical function and lead to frailty. However, appropriate treatment for obesity in older persons is controversial because of the reduction in relative health risks associated with increasing body mass index and the concern that weight loss could have potential harmful effects in the older population. This joint position statement from the American Society for Nutrition and the NAASO, The Obesity Society reviews the clinical issues related to obesity in older persons and provides health professionals with appropriate weight-management guidelines for obese older patients. The current data show that weight-loss therapy improves physical function, quality of life, and the medical complications associated with obesity in older persons. Therefore, weight-loss therapy that minimizes muscle and bone losses is recommended for older persons who are obese and who have functional impairments or medical complications that can benefit from weight loss.