Which MR imaging sequences are necessary in determining the need for radiation therapy for cord compression? A prospective study.

BACKGROUND AND PURPOSE: To determine which MR imaging sequences are necessary to assess for spinal metastases. METHODS: Hypothetical MR imaging interpretations and management plans were made prospectively for consecutive adult cases acquired retrospectively. Standardized MR imaging protocols were independently interpreted by 2 neuroradiologists. MR imaging protocol types varied: 1) T1-weighted images only; 2) T1-weighted and T2-weighted images; 3) T1-weighted and postcontrast T1-weighted images; and 4) T1- and T2-weighted images and postcontrast T1-weighted images. Hypothetical management plans were created by 2 radiation oncologists. Logit model was used to investigate the effect of MR imaging protocol type on the probability of recommending radiation therapy (RT). Mixed effect models were used to investigate whether median spinal level or total number of spinal levels of planned RT was associated with MR imaging protocol type. RESULTS: Thirty-one subjects were evaluated, each with multiple scan interpretations. Logit model showed that neither MR imaging protocol type nor neuroradiologist reader affected the probability that the oncologist would recommend RT (all P > .50). Mixed models showed that neither ML nor NL was affected by MR imaging protocol type or by neuroradiologist reader (all P > .12). CONCLUSION: Although MR imaging is known to be the most useful diagnostic test in suspected spinal cord compression, which particular MR images are necessary remain unclear. Compared with T1-weighted images alone, the additional use of T2-weighted and/or postcontrast T1-weighted sequences did not significantly affect the probability that RT would be recommended or the levels that would be chosen for RT in our study. Our data suggest that unenhanced T1-weighted images may be sufficient for evaluation of possible cord compression.

Evaluation of co-morbidity indices in patients admitted for chronic obstructive pulmonary disease.

BACKGROUND: There is limited and conflicting information on the use of co-morbidity instruments to predict mortality in patients with chronic obstructive pulmonary disease (COPD). METHODS: We sought to test the validity of the Charlson Index and another co-morbidity instrument, the Adult co-morbidity evaluation 27 (ACE-27), in patients admitted with COPD exacerbations. Co-morbidity scores were obtained by chart review. Information on mortality was retrieved from the Social Security Death Index. We examined the predictive validity of the Charlson and the ACE-27 using survival analysis. RESULTS: There were 112 patients eligible for the study. The ACE-27 but not the Charlson predicted survival, after adjusting for age, gender, and smoking history in Cox regression, hazard ratio (95% CI) of 1.99 (1.17-3.39). CONCLUSIONS: This study confirms earlier findings that the Charlson Index is not a reliable predictor of mortality in patients with COPD. However, the ACE-27 appears to be useful for predicting survival in this study.

Usefulness of blood culture for hospitalized patients who are receiving antibiotic therapy.

We conducted a retrospective study to determine the yield of blood samples drawn for culture during the initial 72 h of antibiotic therapy given to 139 patients who were admitted to the hospital for community-acquired infections or fever. The yield of these blood cultures was predictable and rarely (in only 1 patient [0.72%]) isolated new pathogens.

A randomized, placebo-controlled trial of antimicrobial treatment for children with clinically diagnosed acute sinusitis.

OBJECTIVE: Although antimicrobial treatment for children with acute sinusitis is used commonly, it is unclear whether it offers significant clinical benefit. The purpose of this study was to evaluate the effectiveness of antimicrobial treatments for acute sinusitis as they are used in community pediatric practice. METHODS: We conducted a randomized, placebo-controlled trial in 3 community pediatric practices in St Louis, Missouri. A total of 188 patients who were between the ages of 1 and 18 years and who had had 10 to 28 days of persistent sinus symptoms and a clinical diagnosis of acute sinusitis were randomized to receive 14 days of amoxicillin (40 mg/kg/d in 3 daily doses), amoxicillin-clavulanate (amoxicillin 45 mg/kg/d in 2 daily doses), or placebo. Change in sinus symptoms was assessed both by a quantitative symptom score (the S5 score) and subjectively by the parent. Secondary outcomes included adverse effects of treatment and recurrence or relapse of sinus symptoms. Outcomes were assessed by telephone interviews over a 2-month period. RESULTS: Of the 161 patients who were included in the analysis, 58 received amoxicillin, 48 received amoxicillin-clavulanate, and 55 received placebo. Day 14 improvement rates were 79%, 81%, and 79%, respectively. There were no differences in the 14-day change in S5 score among treatment groups. The rates of adverse events (amoxicillin, 19%; amoxicillin-clavulanate, 11%; placebo, 10%), relapse (amoxicillin, 12%; amoxicillin-clavulanate, 13%; placebo, 13%), and recurrence (amoxicillin, 9%; amoxicillin-clavulanate, 13%; placebo, 13%) of sinus symptoms were similar among treatment groups. CONCLUSION: Neither amoxicillin nor amoxicillin-clavulanate offered any clinical benefit compared with placebo for children with clinically diagnosed acute sinusitis.

Evaluation of a reduced MR imaging sequencing protocol in adult patients with stroke.

PURPOSE: To compare a reduced (three-sequence) magnetic resonance (MR) imaging protocol with a full (eight- to 10-sequence) MR imaging protocol in adults suspected of having stroke. MATERIALS AND METHODS: Six neuroradiologists interpreted a consecutive sample of 265 MR images in patients suspected of having stroke. Each read reduced-protocol images in a discrete series of 40 patients (one read images in only 15) and corresponding full-protocol images 1 month later (reduced/full protocol). Five of the readers each read images in 10 additional cases, five each as full/full and reduced/reduced protocol controls. kappa values between full and reduced protocols, reader assessment of protocol adequacy, confidence level, and need for additional sequences or examinations were evaluated. RESULTS: In the reduced/full protocol, the kappa value for detecting ischemia was 0.797; and that for detecting any clinically important abnormality, 0.635. Statistically similar kappa values were found with the full/full control design (kappa = 0.802 and 0.715, respectively). The full protocol was judged more adequate than the reduced protocol (2.0 of 5.0 points vs 1.6, P <.001) and generated greater diagnostic confidence (8.6 of 10.0 points vs 8.9, P =.01), less need for additional sequences (2.7 of 6.0 points vs 1.5, P <.001), and more requests for additional examinations (28.4% vs 36.3%). CONCLUSION: Disagreement between interpretations of reduced- and full-protocol images might be attributable to baseline-level intraobserver inconsistency, as demonstrated in control designs. A greater number of sequences did not lead to greater consistency.

Spiral CT colonography: reader agreement and diagnostic performance with two- and three-dimensional image-display techniques.

PURPOSE: To assess the diagnostic performance and reader agreement with two-dimensional (2D) and three-dimensional (3D) display techniques for detecting colorectal polyps with spiral computed tomographic (CT) colonography. MATERIALS AND METHODS: A test set of 30 colonic segments was developed from spiral CT colonographic studies (12 with polyps and 18 without). The 12 segments with polyps contained 22 lesions (11 polyps <10 mm, 11 polyps or cancers >/=10 mm), with all findings verified with colonoscopy. Three specific 2D and 3D image-display techniques were tested. Three experienced abdominal radiologists independently analyzed each test case and were retested 6 weeks later. RESULTS: The results of readings 1 and 2 were similar for all image-display techniques among the readers. Pooled segment results were sensitivity of 89%-92% and specificity of 72%-83%. Pooled polyp size results for sensitivity and positive predictive value were 77%-86% and 74%-86% (all polyps, n = 22), 91%-100% and 85%-100% (polyps or cancers >10 mm, n = 11), and 61%-73% and 61%-80% (polyps 5-9 mm, n = 11), respectively. Overall intraobserver agreement was good for the three display techniques (kappa, 0.60-1.00); however, interobserver agreement for 2D multiplanar reformation was lower (kappa, 0.53-0.80). CONCLUSION: Among experienced abdominal radiologists, similar diagnostic performance in polyp detection was found among 2D multiplanar reformation and 3D display techniques, although individual cases showed improved characterization with 3D display techniques. Evaluation of reader agreement demonstrated good intraobserver agreement, with variable interobserver agreement.

Randomized controlled trial of sheaths in diagnostic neuroangiography.

PURPOSE: To determine the value of arterial sheaths in diagnostic neuroangiography in a randomized controlled trial. MATERIALS AND METHODS: A total of 842 patients (411 men, 431 women; mean age, 59.4 years; age range, 29.5-94.3 years) undergoing diagnostic neuroangiography were randomly assigned to groups in which a sheath was introduced immediately after puncture of the femoral artery (sheath group) or in which a diagnostic catheter was introduced without a sheath (control group). Two hundred twenty-four (26.7%) of 839 patients were receiving anticoagulants immediately prior to the procedure. RESULTS: Complications (mostly small hematomas of the groin) occurred in 106 (12.6%) of 842 patients, with no difference between groups (53 [12.6%] of 421 patients in both; P >.99). Ease of catheter manipulation was greater in the sheath group than in the control group. Incidence of bleeding at the femoral puncture site during the procedure was less in the sheath group (seven [1.7%] of 421 patients) versus the control group (150 [35.6%] of 421 patients), with a P value less than.001. Because of bleeding, sheath insertion was necessary in 165 (39.2%) of 421 patients in the control group. This crossover group also had a higher rate of local complications (28 [17.0%] of 165 patients) than the sheath and control groups. Serious complications, such as stroke (one [0.12%] of 842 patients) and transient ischemic attacks (five [0.60%] of 842 patients), occurred with equal frequency in both the sheath and control groups. CONCLUSION: Use of arterial sheaths lessens the incidence of intraprocedural bleeding at the femoral puncture site and increases ease of catheter manipulation without increasing the number of groin complications.

Using the free-to-total prostate-specific antigen ratio to detect prostate cancer in men with nonspecific elevations of prostate-specific antigen levels.

BACKGROUND: Prostate-specific antigen (PSA) levels between 4.0 to 10.0 ng/ml have poor specificity in prostate cancer screening, leading to unnecessary biopsies. OBJECTIVE: To determine whether the free-to-total PSA ratio (F/T PSA) improved the diagnostic accuracy of these nonspecific PSA levels. MEASUREMENTS AND MAIN RESULTS: MEDLINE searchedwas from 1986 to 1997. Additional studies were identified from article bibliographies and by searching urology journals. Two investigators independently identified English-language studies providing F/T PSA ratio test-operating characteristics data on > or = 10 cancer patients with PSA values between 2.0 and 10.0 ng/ml. Twenty-one of 90 retrieved studies met selection criteria. Two investigators independently extracted data on methodology and diagnostic performance. Investigator-selected cut points for the optimal F/T PSA ratio had a median likelihood ratio of 1.76 (interquartile range, 1.40 to 2.11) for a positive test and 0.27 (0.20 to 0.40) for a negative test. Assuming a 25% pretest probability of cancer, the posttest probabilities were 37% following a positive test and 8% following a negative test. The summary receiver operating characteristic curve showed that maintaining test sensitivity above 90% was associated with false positive rates of 60% to 90%. Methodologic problems limited the validity and generalizability of the literature. CONCLUSIONS: A negative test reduced the posttest probability of cancer to approximately 10%. However, patients may find that this probability is not low enough to avoid undergoing prostate biopsy. The optimal F/T PSA ratio cut point and precise estimates for test specificity still need to be determined.

Utility-based estimates of the relative morbidity of visual impairment and angina.

PURPOSE: To quantify and compare the reduction in quality of life due to visual impairment and angina using patient preferences (utilities). METHODS: Using a standard time tradeoff method, we obtained utilities for current vision, monocular and binocular blindness, current angina, and moderate angina in 60 patients with both vision problems and angina pectoris who sought care at the National Eye Institute (NEI), National Naval Medical Center, or Barnes-Jewish Hospital. Patients were characterized clinically based on visual acuity and the Duke Activity Status Index (DASI). Patients also completed a seven-item version of the NEI Visual Functioning Questionnaire and the SF-36 Health Survey Questionnaire. RESULTS: Patients had a median visual acuity of 20/100 in the worst eye, 20/40 in the better eye, and a median DASI of 24.2 (0 = severe functional limitations due to anginal symptoms, 58.2 = no limitations). There was substantial variation in utilities among patients. The average utility for current vision (relative to ideal vision [= 1.0] and death [= 0.0]) was 0.82; the average utility for current angina (relative to no angina symptoms [= 1.0] and death [ = 0.0]) was 0.89. Among 26 patients with both visual impairment and recent anginal symptoms, the decrement in utility (on a scale ranging from ideal health [= 1.0] to death [= 0.0]) imposed by current visual impairment was greater than that imposed by current angina symptoms (0.146 versus 0.072, p=0.08, Wilcoxon signed rank test). The decrement in utility associated with binocular blindness was greater than the decrement associated with the symptoms of moderate angina (0.477 versus 0.039, p<0.0001). CONCLUSIONS: Clinical status is not a surrogate for patient preferences regarding vision impairment or angina. There is substantial variation in utilities within the study population for both experienced and theoretical impairment states which is not explained by variations in clinical status. Some states of visual impairment may pose a greater quality of life burden than anginal symptoms. Because patient preferences for vision vary greatly, individual assessment is warranted for consideration in therapeutic decision making.

Medical and surgical treatment of parapneumonic effusions : an evidence-based guideline.

OBJECTIVE: A panel was convened by the Health and Science Policy Committee of the American College of Chest Physicians to develop a clinical practice guideline on the medical and surgical treatment of parapneumonic effusions (PPE) using evidence-based methods. OPTIONS AND OUTCOMES CONSIDERED: Based on consensus of clinical opinion, the expert panel developed an annotated table for evaluating the risk for poor outcome in patients with PPE. Estimates of the risk for poor outcome were based on the clinical judgment that, without adequate drainage of the pleural space, the patient with PPE would be likely to have any or all of the following: prolonged hospitalization, prolonged evidence of systemic toxicity, increased morbidity from any drainage procedure, increased risk for residual ventilatory impairment, increased risk for local spread of the inflammatory reaction, and increased mortality. Three variables, pleural space anatomy, pleural fluid bacteriology, and pleural fluid chemistry, were used in this annotated table to categorize patients into four separate risk levels for poor outcome: categories 1 (very low risk), 2 (low risk), 3 (moderate risk), and 4 (high risk). The panel's consensus opinion supported drainage for patients with moderate (category 3) or high (category 4) risk for a poor outcome, but not for patients with very low (category 1) or low (category 2) risk for a poor outcome. The medical literature was reviewed to evaluate the effectiveness of medical and surgical management approaches for patients with PPE at moderate or high risk for poor outcome. The panel grouped PPE management approaches into six categories: no drainage performed, therapeutic thoracentesis, tube thoracostomy, fibrinolytics, video-assisted thoracoscopic surgery (VATS), and surgery (including thoracotoiny with or without decortication and rib resection). The fibrinolytic approach required tube thoracostomy for administration of drug, and VATS included post-procedure tube thoracostomy. Surgery may have included concomitant lung resection and always included postoperative tube thoracostomy. All management approaches included appropriate treatment of the underlying pneumonia, including systemic antibiotics. Criteria for including articles in the panel review were adequate data provided for >/=20 adult patients with PPE to allow evaluation of at least one relevant outcome (death or need for a second intervention to manage the PPE); reasonable assurance provided that drainage was clinically appropriate (patients receiving drainage were either category 3 or category 4) and drainage procedure was adequately described; and original data were presented. The strength of panel recommendations on management of PPE was based on the following approach: level A, randomized, controlled trials with consistent results or individual randomized, controlled trial with narrow confidence interval (CI); level B, controlled cohort and case control series; level C, historically controlled series and case series; and level D, expert opinion without explicit critical appraisal or based on physiology, bench research, or "first principles." EVIDENCE: The literature review revealed 24 articles eligible for full review by the panel, 19 of which dealt with the primary management approach to PPE and 5 with a rescue approach after a previous approach had failed. Of the 19 involving the primary management approach to PPE, there were 3 randomized, controlled trials, 2 historically controlled series, and 14 case series. The number of patients included in the randomized controlled trials was small; methodologic weaknesses were found in the 19 articles describing the results of primary management approaches to PPE. The proportion and 95% CI of patients suffering each of the two relevant outcomes (death and need for a second intervention to manage the PPE) were calculated for the pooled data for each management approach from the 19 articles on the primary management approach. (ABST

Association between resistance to vancomycin and death in cases of Enterococcus faecium bacteremia.

We conducted a retrospective cohort study to determine the association between resistance to vancomycin and mortality among hospitalized patients with Enterococcus faecium bacteremia. We compared outcomes for patients infected with vancomycin-resistant versus vancomycin-susceptible E. faecium among 69 patients with bacteremia defined according to the National Nosocomial Infections Surveillance system. The univariate odds ratio (OR) for death associated with vancomycin resistance was 2.1 (P=.172). After controlling for severity of illness, we found that vancomycin resistance was not associated with mortality (OR, 1.74; 95% confidence interval, 0.5-6.12; P=.39). Vancomycin resistance does not independently increase mortality among patients with E. faecium bacteremia.

Enteric carriage of vancomycin-resistant Enterococcus faecium in patients tested for Clostridium difficile.

OBJECTIVE: To identify independent risk factors for enteric carriage of vancomycin-resistant Enterococcus faecium (VREF) in hospitalized patients tested for Clostridium difficile toxin. DESIGN: Retrospective case-cohort study. SETTING: Tertiary-care teaching hospital. PATIENTS: Convenience sample of 215 adult inpatients who had stool tested for C difficile between January 29 and February 25, 1996. RESULTS: 41 (19%) of 215 patients had enteric carriage of VREE Five independent risk factors for enteric VREF were identified: history of prior C difficile (odds ratio [OR], 15.21; 95% confidence interval [CI95], 3.30-70.10; P < .001), parenteral treatment with vancomycin for > or = 5 days (OR, 4.06; CI95, 1.54-10.73; P = .005), treatment with antimicrobials effective against gram-negative organisms (OR, 3.44; CI95, 1.20-9.87; P = .021), admission from another institution (OR, 2.95; CI95, 1.21-7.18; P =.017), and age > 60 years (OR 2.57; CI95, 1.13-5.82; P = .024). These risk factors for enteric VREF were independent of the patient's current C difficile status. CONCLUSIONS: Antimicrobial exposures are the most important modifiable independent risk factors for enteric carriage of VREF in hospitalized patients tested for C difficile.

The development and validation of an instrument to assess acute sinus disease in children.

Our goal was to produce a reliable, responsive instrument to quantify disease burden in children with acute sinusitis for use in clinical trials. In a cross sectional survey of 1611 community pediatric patients, parents rated the burden attributable to 13 sinus symptoms. Using logistic regression, we identified five symptoms that predicted the clinical diagnosis of sinusitis. The S5 is the average symptom score for nasal obstruction, daytime and nighttime coughing, headache and colored nasal discharge (range 0-3). The S5 was high in children with acute sinusitis (mean = 1.54, SD = 0.77, N = 93), and low in well children (mean = 0.42, SD = 0.56, N = 1019). We assessed reliability and responsiveness of S5 in a prospective cohort study of 41 children with sinusitis. Parents completed a questionnaire at the office visit, at 12 h and 3, 7, 10 and 14 days. Intra-subject reliability at 12 h was excellent (ICC = 0.94). The S5 score was responsive in 24 patients followed for 14 days who improved (mean change = 1.52, SD = 0.12, p = 0.0062). The S5 score is standardized, reliable, responsive, easily obtained, and can be used to determine study eligibility and assess treatment effects without a physician's evaluation.

Meta-analysis of randomized controlled trials comparing laparoscopic and open appendectomy.

We performed a meta-analysis to determine whether laparoscopic or open appendectomy gives better outcomes for patients with suspected acute appendicitis. Studies were selected from the MEDLINE database, personal files, and meeting abstracts. Eleven of 21 randomized controlled trials were included in the meta-analysis. Pooled effect size estimates were calculated using a random effects model. Laparoscopic appendectomy reduced time to full functioning by 5.48 days (95% confidence interval [CI] 3.70 to 7.26; p < 0.001), improved postoperative pain at 24 hours measured by a visual analog scale from 0 to 10 by 1.19 points (95% CI -2.14 to -0.24 points; p=0.014), and decreased the absolute risk for wound infection by 3.2% (95% CI -5.6% to -0. 8%; p=0.009). Operating time was increased by 17.12 min (95% CI 14.19 to 20.03; p < 0.0001). There was no difference between the two surgeries for length of hospital stay, readmission rate, and intra-abdominal abscess formation. Laparoscopic appendectomy improves patient outcomes.

Effectiveness of helicopter versus ground ambulance services for interfacility transport.

BACKGROUND: Helicopters provide rapid interfacility transport, but the effect on patients is largely unknown. METHODS: Patients requested to be transported between facilities by helicopter were followed prospectively to determine survival, disability, health status, and health care utilization. A total of 1,234 patients were transported by the primary aeromedical company; 153 patients were transported by ground and 25 patients were transported by other aeromedical services because of weather or unavailability of aircraft. RESULTS: There were no differences at 30 days for survivors in disability, health status, or health care utilization. Nineteen percent of helicopter-transported patients died compared with 15% of those transported by ground (p=0.21). CONCLUSION: The patients transported by helicopter did not have improved outcomes compared with patients transported by ground. These data argue against a large advantage of helicopters for interfacility transport. A randomized trial is needed to address these issues conclusively.

Closed fractures of the tibial shaft. A meta-analysis of three methods of treatment.

We reviewed the literature to determine the clinical outcomes of the treatment of closed fractures of the tibial shaft with immobilization in a cast, open reduction with internal fixation, or fixation with an intramedullary rod. We reviewed 2372 reports of comparative trials and uncontrolled studies of series of patients published between 1966 and 1993. Nineteen reports, involving six controlled trials and twenty-seven groups of patients, met our inclusion criteria. A structured questionnaire was used to assess the quality of the literature in terms of the experimental design and the method of assessment of outcome. Outcomes from controlled trials were summarized with odds ratios and risk differences, and outcomes from case series were summarized by the medians of the reported results. The studies that were reviewed generally had few subjects and were poorly designed. The comparative trials showed treatment with a cast to be associated with a lower rate of superficial infection than open reduction and internal fixation (mean difference, -5.81 per cent; p = 0.02) and open reduction and internal fixation to be associated with a higher rate of union by twenty weeks than treatment with a cast (mean difference, -18.07 per cent; p = 0.008). There were no other significant associations. There were insufficient data for us to evaluate any aspect of functional status, level of pain, or other patient-reported outcomes of any of the methods of treatment. The results of the present review suggest that the data from the published literature are inadequate for decision-making with regard to the treatment of closed fractures of the tibia.

A meta-analysis of extended-interval dosing versus multiple daily dosing of aminoglycosides.

We conducted a meta-analysis of 22 randomized, controlled trials in which extended-interval dosing of aminoglycosides was compared with multiple daily dosing. When we classified intermediate outcomes as successes, we found that patients receiving extended-interval dosing were at significantly reduced risk of clinical treatment failure (risk difference, -3.4%; 95% confidence interval [CI], -6.7% to -0.2%; P = .039) and that there was a trend toward reduced risk of bacteriologic failure (risk difference, -1.7%; 95% CI, -5.4% to +2.1%; P = .38). Reclassification of intermediate outcomes as failures yielded similar results. There was significant heterogeneity among the trials, necessitating cautious interpretation of these outcomes. There were negligible differences in the risk of nephrotoxicity (risk difference, -0.6%; 95% CI, -2.4% to +1.1%; P = .46) and ototoxicity (risk difference, +0.3%; 95% CI, -1.2% to +1.8%; P = .71). We conclude that for many indications, extended-interval dosing of aminoglycosides appears to be as effective as conventional dosing, with similar rates of toxicity. The added convenience of extended-interval dosing makes it an attractive alternative to conventional dosing.

Surgeons' decision making in patients with chronic wrist pain: role of bilateral three-compartment wrist arthrography--prospective study.

PURPOSE: To determine if wrist arthrography changes surgeons' diagnoses and treatment plans for patients with chronic wrist pain. MATERIALS AND METHODS: Bilateral, three-compartment wrist arthrography was performed in 64 patients. Prospective questionnaires evaluated surgeons' diagnoses and management plans at three stages: before arthrography, after arthrography of the symptomatic wrist, and after arthrography of the asymptomatic wrist. RESULTS: Surgeons tended to plan more conservative management after receiving the results of arthrography. The number of patients for whom the reported treatment plan included surgery dropped from 28 of 64 patients (44%) to 19 of 64 patients (30%) after review of the arthrography results (P = .05). The number of patients for whom the treatment plan included treatment of any kind dropped from 55 of 64 patients (86%) to 49 of 64 patients (77%) after review of the arthrography results (P = .09). An overall change in treatment plan occurred in 29 of 64 patients (45%). CONCLUSION: Wrist arthrography influences surgeons' decision making. After reviewing the results of arthrography, surgeons tended to change treatment plans toward more conservative, less invasive treatment.