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J G Wright

Publications and source records attributed to J G Wright.

At least 55 records · Page 3Linked to original sources
PubMed1999

Outcomes research: what to measure.

Surgeons assess the outcomes of treatment to determine if treatment is effective. The most commonly used types of outcomes have been measures of disease process (or impairment measures) because surgery is often directed toward ameliorating abnormalities of structure or function. Patient-based outcomes, such as measures of health or health-related quality of life, are necessary, however, to determine if patients have been made better by treatment. Disease-specific measures of health focus specifically on those aspects of the disease of most concern to patients, whereas generic measures of health and health-related quality-of-life measures have a much broader focus. Patient satisfaction is an additional increasingly used outcome measure. Satisfaction may be directed toward the processes of care or the outcomes of care. Satisfaction with the outcomes of care is an important secondary outcome provided the aims of treatment have been achieved and the health of patients has been improved. In conclusion, different outcomes of treatment provide different and complementary information and all have a role to play in deciding if surgical treatments are effective.

Clinical Trials as Topic↗
PubMed1999

Postsplenectomy course in homozygous sickle cell disease.

OBJECTIVE: To determine whether children with homozygous sickle cell (SS) disease and splenectomy are at greater risk of death, overwhelming septicemia, or other complications. METHODS: A total of 130 patients with SS treated by splenectomy (46 recurrent acute splenic sequestration, 84 chronic hypersplenism) over a 22.5-year period at the Sickle Cell Clinic of the University Hospital of the West Indies, Kingston, Jamaica, were compared with a control group matched for sex, age, and duration of follow-up in a retrospective review. Deaths and bacteremias were examined over the whole study period. Painful crises, acute chest syndromes, and febrile episodes were compared in the 90 patients completing 5 years of postsplenectomy follow-up. FINDINGS: Mortality and bacteremic episodes did not differ between the splenectomy and control groups. Painful crises were more common in the splenectomy group than in the control group (P =.01) but did not differ between splenectomy indications. Acute chest syndrome was more common in the splenectomy group than in the control group (P <.01) and was more common in the acute splenic sequestration group than in the hypersplenism group (P =.01). Febrile events did not differ between the groups or between the indications for splenectomy. CONCLUSION: Splenectomy does not increase the risk of death or bacteremic illness in patients with SS disease and, if otherwise indicated, should not be deferred for these reasons.

Adolescent↗
PubMed1999

The modified Norwood procedure for hypoplastic left heart syndrome: early to intermediate results of 120 patients with particular reference to aortic arch repair.

BACKGROUND: Classic first-stage Norwood repair of hypoplastic left heart syndrome uses a homograft patch enlargement to obtain an unobstructed aorta and coronary arteries. Because of possible disadvantages of the homograft, such as lack of growth, degeneration and calcification, and availability, we have tried to repair the aorta without patch supplementation. METHODS: Between February 1993 and September 1997, 120 patients, aged birth to 47 days (median 4 days) and weighing 1.7 to 4.4 kg (median 3.1 kg), underwent first-stage palliation for hypoplastic left heart syndrome. The diameter of the ascending aorta ranged from 1.5 to 8.0 mm (median 3.0 mm). Eight patients had an aberrant right subclavian artery arising from the descending thoracic aorta. In 95 patients (group I), all duct tissue was excised and the descending aorta was anastomosed to the aortic arch, which had been opened back into the ascending aorta. Then to this confluence was anastomosed the proximal main pulmonary artery. In the remaining 25 patients (group II), continuity of the aortic arch was maintained and the repair was performed with a Damus-Kaye-Stansel anastomosis. The size of the systemic-to-pulmonary shunt was 3 mm in 48 patients, 3.5 mm in 70, and 4.0 mm in 2. RESULTS: Circulatory arrest time ranged from 19 to 105 minutes (median 54 minutes). A homograft patch was necessary for the arch reconstruction in 18 patients (15%); 9 group I patients (10%) and 9 group II (36%) (P =.001). There were 82 hospital survivors (68%); 69 group I patients (73%) and 13 group II (52%) (P =.04), 71 patients without a patch (70%) and 11 with a patch (61%) (P >.2). By multiple logistic regression, the aberrant right subclavian artery was a significant risk factor for hospital death (P =.008). There were 6 late deaths. Sixteen of 71 patients (23%) who underwent second-stage palliation had a neoaortic arch obstruction develop, with a peak gradient greater than 10 mm Hg; 14 group I patients (23%) and 2 group II (22%) ( P >.2), 15 without a patch (23%) and 1 with a patch (17%) (P >.2). Overall survivals were 57% at 1 year and 55% at 2 years. CONCLUSION: The modified Norwood procedure for first-stage palliation of hypoplastic left heart syndrome is possible in the majority of patients without the use of exogenous materials and does not result in an increased incidence of neoaortic arch obstruction. Repair of the aorta without patch supplementation may improve the potential for long-term growth of the new aorta.

Anastomosis, Surgical↗
PubMed1999

Clinimetric and psychometric strategies for development of a health measurement scale.

Clinimetrics and psychometrics, two accepted methods for developing multiitem health measurement scales, have fundamentally different aims and methods that have seldom been compared and never prospectively. The purpose of this study was to determine whether these two methodologies provided comparable scales in the development of an upper extremity disability measure. Psychometric analysis involved field testing a 70-item questionnaire on 407 patients. Equidiscriminatory item total correlation (EITC) was used to select the top 30 items. Clinimetric testing used the mean importance and severity ratings of the 70 items by 76 patients to select the top 30 items. Clinimetric and psychometric analyses were performed independently. Cronbach's alpha was 0.97 for the top 30 items selected by EITC and 0.96 for the items selected based on patient's ratings. The two scales (after clinician modification to improve face validity) shared 16 items in common (P=0.10). The intraclass correlation coefficient of the patient scores on the two 30-item scales was 0.93 before clinician input and 0.97 after. The mean (and standard deviation) difference between scales was 9.1 (8.8) before and 1.7 (5.2) after clinician input. A scale developed with a clinimetric strategy can measure a complex (so-called heterogeneous) clinical phenomenon (thought to be composed of several patient attributes) but still fulfill psychometric criteria for "homogeneity." Thus, these strategies for the development of health measurement scales, which have been considered potentially opposite or conflicting, may be complementary.

Adult↗
PubMed1999

How should importance and severity ratings be combined for item reduction in the development of health status instruments?

Patients' ratings of the severity and importance of items are often used to select items for health status instruments. The purpose of this study was to compare six different methods of combining severity-importance ratings. Two different patient groups separately rated the importance and severity of their complaints; (i) 76 patients with upper-extremity disorders rated 70 upper-extremity-related questions; and (ii) 86 patients with hip arthrosis rated 22 questions relating to their hip problem. The rank ordering of the items using the six different methods in the two populations were very similar (tau(bi) = 0.91 and 0.87, respectively). Furthermore, the six methods when used to choose 30 upper-extremity items shared 25 items in common and shared 9 (of 10) hip items in the second group. In conclusion, the results of item reduction were not affected by the method of creating importance-severity ratings.

Activities of Daily Living↗
PubMed1999

Total anomalous pulmonary venous connection: outcome of surgical correction and management of recurrent venous obstruction.

OBJECTIVE: Total anomalous pulmonary venous connection (TAPVC) can be corrected with low mortality and good outcome. If complicated by pulmonary vein stenosis (PVS), either at presentation or secondary to the repair, the long-term outcome is compromised. We have evaluated an institutional experience with TAPVC, with particular regard to the evolving management of PVS. METHODS: Retrospective analysis of 85 consecutive patients with non-isomeric TAPVC undergoing surgical correction over a 10-year period (1988-1997). In addition, three patients were referred to us with secondary PVS, having had their primary procedure elsewhere. Attention was focused on incidence of PVS, and strategies for management. RESULTS: Median age at first operation was 33 days (range 1-533). Site of drainage was supracardiac (43/88), infracardiac (20/88), cardiac (17/88), and mixed (8/88). On presentation, 35% of patients were ventilated. Early mortality was 7% (6/85), with one late non-cardiac death. 82% of the original patients (70/85) are currently well at a median follow-up of 64 months (range 6-119). The incidence of PVS requiring intervention was 11% (9/85). Median time to PVS was 41 days. In these patients, 18 balloon angioplasties, four endovascular stent placements (in two patients), and a further 23 surgical procedures were performed. Of the nine patients undergoing re-intervention after initial surgery at our institution, five (56%) survived. Two of these have no residual obstruction and right ventricular pressure (RVP) < 50% systemic, two have unilateral obstruction and RVP < 50% systemic, and one has bilateral obstruction and RVP 80% systemic. Of the three patients referred to us with secondary PVS, two are alive and well, and one died early after the first re-operation. CONCLUSIONS: Intrinsic obstruction (endocardial sclerosis or thickening) is associated with worse prognosis and earlier re-intervention than extrinsic (anatomical) obstruction. We advocate an early, aggressive approach to the management of patients with TAPVC, especially in the presence of PVS. This complication is most appropriately managed by a combination of re-operation and repeated balloon dilation.

Angioplasty, Balloon↗
PubMed1999

What do we know about the reliability and validity of physical examination tests used to examine the upper extremity?

The literature regarding the reliability and validity of commonly used clinical tests for disorders of the upper extremity was reviewed. Formal literature search, standard texts, and experts in the field of upper extremity were consulted to locate relevant articles. Range of motion and strength testing of the upper limb have been shown to be reliable, while various tests used for the diagnosis of conditions in the upper limb, such as carpal tunnel syndrome and rotator cuff tendinopathy, have been shown to have varying degrees of validity. Overall, however, we determined that there is little evidence regarding the reliability and validity of physical examination for the upper extremity and specifically less information available regarding the reliability of diagnostic physical examination tests and the validity of impairment measures used for the upper limb. Further studies in this area are warranted in view of the impact of these findings on the treatment of patients.

Arm↗
PubMed1999

Physician enthusiasm as an explanation for area variation in the utilization of knee replacement surgery.

BACKGROUND: Explanations for regional variation in the use of many medical and surgical treatments is controversial. OBJECTIVES: To identify factors that might be amenable to intervention, we investigated the determinants of regional variation in the use of knee replacement surgery. RESEARCH DESIGN: We examined the effect of the following factors: characteristics and opinions of surgeons; family physicians and rheumatologists; patients' severity of disease before knee replacement; access to knee-replacement surgery; surgeons' use of other surgical treatment; and county population characteristics. OUTCOMES MEASURE: County utilization rates of knee replacement in Ontario, Canada. RESULTS: Counties that had higher rates of knee replacement had older patients (P = 0.0001), higher percentage of medical school affiliated hospital beds (P = 0.04), with more male (P = 0.02) non-North American trained referring physicians (P = 0.002) and orthopedic surgeons who had higher propensities to operate and better perceptions of outcome (P = 0.0001). CONCLUSIONS: After controlling for population characteristics and access to care (including the number of hospital beds, and the density of orthopaedic and referring physicians), orthopaedic surgeons' opinions or enthusiasm for the procedure was the dominant modifiable determinant of area variation. Thus, research needs to focus on the opinions of surgeons which may be important in reducing regional variation for knee replacement.

Adult↗
PubMed1999

Enhanced endothelial vasoreactivity in endurance-trained older men.

Using external vascular ultrasound, we measured brachial artery diameter (Diam) at rest, after release of 4 min of limb ischemia, i. e., endothelium-dependent dilation (EDD), and after sublingual nitroglycerin, i.e., non-endothelium-dependent dilation (NonEDD), in 35 healthy men aged 61-83 yr: 12 endurance athletes (A) and 23 controls (C). As anticipated, treadmill exercise maximal oxygen consumption (VO(2 max)) was significantly higher in A than in C (40. 2 +/- 6.6 vs. 27.9 +/- 3.8 ml. kg(-1). min(-1); respectively, P < 0. 0001). With regard to arterial physiology, A had greater EDD (8.9 +/- 4.2 vs. 5.7 +/- 3.5%; P = 0.02) and a tendency for higher NonEDD (13.9 +/- 6.7 vs. 9.7 +/- 4.2%; P = 0.07) compared with C. By multiple linear regression analysis in the combined sample of older men, only baseline Diam (beta = -2.0, where beta is the regression coefficient; P = 0.005) and VO(2 max) (beta = 0.23; P = 0.003) were independent predictors of EDD; similarly, only Diam (beta = -4.0; P = 0.003) and VO(2 max) (beta = 0.27; P = 0.01) predicted NonEDD. Thus endurance-trained older men demonstrate both augmented EDD and NonEDD, consistent with a generalized enhanced vasodilator responsiveness, compared with their sedentary age peers.

Aged↗
PubMed1999

Rates of revision knee replacement in Ontario, Canada.

BACKGROUND: The present study was designed to measure the longevity of knee replacements and to assess the determinants of revision knee replacements in order to enhance the potential for informed decision-making. METHODS: Data on all hospitalizations for knee replacement that occurred in Ontario, Canada, between April 1, 1984, and March 31, 1991, were acquired. To calculate the rates of revision knee replacement, two algorithms were developed: one distinguished primary knee replacements from revision knee replacements, and the second linked revision knee replacements to primary knee replacements. The Kaplan-Meier method was used to assess survivorship (absence of a revision) for primary knee replacement. A proportional-hazards regression model was estimated to assess the role of independent variables on the survival of primary knee replacements. RESULTS: During the period of the study, 7.0 percent (1301) of 18,530 knee replacements were classified as revisions. Significant differences were identified between hospitalizations for primary and revision knee replacements in terms of the patient and hospital characteristics. Patients who were more than fifty-five years old, lived in a rural area, or had a diagnosis of rheumatoid arthritis had a significantly (p < 0.05) longer duration before revision than did other patients. Primary knee replacements performed in a teaching or specialty hospital had a significantly (p < 0.05) shorter duration before revision than did those performed in a non-teaching hospital. The long-term rates of revision were uniformly low. Estimates of the proportion of knee replacements that would need to be revised within seven years ranged from a low of 4.3 percent, with use of the algorithm for the longest time to revision, to a high of 8.0 percent, with use of the algorithm for the shortest time to revision. CONCLUSIONS: Revision of a primary knee replacement was a rare event that depended on a patient's age, gender, and place of residence as well as on the hospital where the primary knee replacement was performed. Estimates of the rates of revision knee replacement after almost seven years ranged from a low of 4.3 percent to a high of 8.0 percent.

Aged↗
PubMed1999

Slipped capital femoral epiphysis after septic arthritis of the hip in an adolescent: report of a case.

Septic arthritis of the hip must be managed promptly to avoid the serious complications associated with the condition. In the case reported here, the diagnosis was delayed and was complicated by a slipped capital femoral epiphysis. The patient, an adolescent boy previously in good health, presented with a 2-week history of hip pain and systemic illness. Septic arthritis was diagnosed and was managed by incision and drainage and antibiotic therapy. Two weeks later he presented with a subcutaneous abscess and a slipped capital femoral epiphysis, which was pinned in situ. There was a 2.5-cm leg-length discrepancy. Avascular necrosis of the femoral head subsequently developed leaving the boy with a permanent disability.

Adolescent↗
PubMed1998

A comparative study of TLSO, Charleston, and Milwaukee braces for idiopathic scoliosis.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To determine which of TLSO, Charleston, or Milwaukee bracing best prevents curve progression and surgery in adolescent idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Bracing has been shown to prevent curve progression in idiopathic scoliosis, when compared with no treatment. However, there is little literature available comparing the effectiveness of different brace designs. METHODS: One hundred seventy patients who completed brace treatment for adolescent idiopathic scoliosis between 1988 and 1995 were studied. Forty-five thoracolumbosacral orthoses, 95 Charleston braces, and 35 Milwaukee braces were used. Thoracolumbosacral orthoses and Charleston braces were used on comparable curves, whereas Milwaukee braces were used in a subgroup in which the other brace designs were considered inappropriate. Evaluated were the absolute increase in curve severity, the percentage of curves that progressed beyond 6 degrees and 10 degrees thresholds, and the percentage of patients who underwent surgery. RESULTS: Age, Risser stage, curve size, and time braced and observed did not differ among groups. Mean progression of the curve during bracing was 1.1 degrees with thoracolumbosacral orthosis, 6.5 degrees with the Charleston brace, and 6.3 degrees with the Milwaukee brace (P = 0.012; analysis of variance). Proportion of patients with more than 10 degrees of curve progression was 14% with thoracolumbosacral orthosis, 28% with the Charleston brace, and 43% with the Milwaukee brace (P = 0.017; chi-square). The proportion of patients who underwent surgery was 18% with thoracolumbosacral orthosis, 31% with the Charleston brace, and 23% with the Milwaukee brace (P = 0.26; chi-square). CONCLUSIONS: The thoracolumbosacral orthosis was superior at preventing curve progression in adolescent idiopathic scoliosis.

Adolescent↗
PubMed1998

Independent prognostic significance of ischemic ST-segment response limited to recovery from treadmill exercise in asymptomatic subjects.

BACKGROUND: Although exercise-induced ST depression is an independent predictor of future coronary events in asymptomatic populations, the predictive value of ST depression beginning after exercise cessation is unknown. METHODS AND RESULTS: We analyzed the treadmill exercise tests of 825 healthy volunteers who were 22 to 89 years of age from the Baltimore Longitudinal Study of Aging. All subjects were free from coronary heart disease by history, physical examination, and resting ECG. From 825 participants, 611 (group 0) had no ischemic ST-segment changes during or after treadmill exercise, while 214 subjects developed > or = 1-mm flat or downsloping ST depression: 151 (group 1) had ST changes starting during exercise, and 63 (group 2) had changes limited to recovery. Groups 1 and 2 were similar in age, sex, smoking status, hypertension prevalence, fasting plasma glucose, and serum cholesterol (CHOL). However, both groups were older and had higher CHOL and prevalence of hypertension than group 0. Treadmill exercise duration, peak oxygen consumption, and maximal heart rate were similar between groups 1 and 2 but were lower than in group 0 (each P < 0.05). During a mean follow-up time of 9 years, 55 subjects developed coronary events (angina pectoris, myocardial infarction, or coronary death): 21 of 611 (3.4%) in group 0, 22 of 151 (14.6%) in group 1, and 12 of 63 (19%) in group 2 (P = 0.001). By survival analysis, the risk of coronary events was similar in groups 1 and 2 but significantly higher than in group 0 (P < 0.0001). Multiple logistic regression showed that age (odds ratio [OR] = 1.07 per year, P = 0.00001), CHOL (OR = 1.02 per 1 mg, P = 0.0001), and presence of ST-segment depression (OR = 2.59, P = 0.007 and OR = 2.38, P = 0.04 for groups 1 and 2, respectively) were independent predictors of events. CONCLUSIONS: Thus, ischemic ST-segment changes developing during recovery from treadmill exercise in apparently healthy individuals have adverse prognostic significance similar to those appearing during exercise.

Adult↗
PubMed1998

The reliability of physical examination for carpal tunnel syndrome.

The goal of this study was to determine the interobserver and intraobserver reliability of static and moving two-point discrimination, Semmes-Weinstein monofilament testing, Tinel's test, manual motor testing of abductor pollicis brevis, vibration and Phalen's test in the diagnosis of carpal tunnel syndrome. Twelve patients with suspected carpal tunnel syndrome were examined in an outpatient setting. The interobserver reliability was satisfactory for all tests except for Semmes-Weinstein monofilament testing. Intraobserver reliability was also satisfactory for all tests. Static two point discrimination had higher reliability than moving two-point discrimination. Seven tests for the diagnosis of carpal tunnel syndrome were reliable in the hands of skilled health care professionals. Hand surgeons and hand therapists examined patients more reliably than occupational health workers.

Adult↗
PubMed1998

Recovery pattern of left ventricular dysfunction following radiofrequency ablation of incessant supraventricular tachycardia in infants and children.

OBJECTIVE: To assess recovery pattern of left ventricular function secondary to incessant tachycardia after radiofrequency ablation in a group of infants and children. DESIGN AND SETTING: A combined prospective and retrospective echocardiographic study carried out in a tertiary paediatric cardiac centre. PATIENTS: Echocardiographic evaluation of left ventricular size and function in nine children with incessant tachycardia, before and after successful radiofrequency ablation. Age at ablation ranged from 2 months to 12.5 years (mean 4.1 years). Recovery of left ventricular function was analysed in relation to age at ablation (group I < 18 months, group II > 18 months). MAIN OUTCOME MEASURE: Ventricular recovery pattern. RESULTS: Seven of the nine children had left ventricular dysfunction; six of these also had left ventricular dilatation. All children with left ventricular dysfunction had normalisation of ejection fraction and fractional shortening; left ventricular dilatation also improved, but the improvement occurred after recovery of function. There was a shorter recovery time for left ventricular function in younger (group I) than in older children (group II) (mean (SD) 5.7 (7.2) months v 31.3 (5.2) (p < 0.002). CONCLUSIONS: Tachycardia induced cardiomyopathy is reversible following curative treatment with radiofrequency. Recovery of left ventricular systolic function precedes recovery of left ventricular dilatation. Time course to recovery is shorter in younger children.

Age Factors↗
PubMed1998

Patient characteristics that affect the outcome of total hip arthroplasty: a review.

OBJECTIVE: To review the literature regarding patient factors pertinent to the outcome of total hip arthroplasty (THA). DATA SOURCE: MEDLINE from 1966 onward (key words "hip prosthesis" and "treatment outcome") and literature previously known to the authors and cited in papers from all sources. STUDY SELECTION: All identified studies were included provided the methodology permitted assessment of the effect of patient factors and a clear outcome was defined (either prosthesis survival or specific functional outcomes). DATA EXTRACTION: The patient factors, methods and outcomes described in each paper were summarized on a data extraction form. DATA SYNTHESIS: All data were reviewed by one author. This process was repeated by a second author, and the findings were reviewed by the remaining 2 authors to verify the findings. The best functional outcomes and prosthesis survival rates were reported among patients who were between 45 and 75 years of age, weighed less than 70 kg, had strong social support, had a higher educational level, had better preoperative functional status and had no comorbid disease. CONCLUSION: Important research remains to be done to examine the magnitude and interaction of patient factors on the the outcome of THA.

Age Factors↗
PubMed1998

The effect of hospital volume on the in-hospital complication rate in knee replacement patients.

OBJECTIVE: To examine the effect of hospital volume on in-hospital surgical outcomes for knee replacement using six years of Medicare claims data. DATA SOURCES/STUDY SETTING: The data include inpatient claims for a 100 percent sample of Medicare patients who underwent primary knee replacement during 1985-1990. We supplemented these data with information from HCFA's denominator files, the Area Resource File, and the American Hospital Association survey files. STUDY DESIGN: We estimated the probability that a patient has an in-hospital complication in the initial hospitalization for the first primary knee replacement, using a Logit model, for three definitions of complication. The models controlled for hospital volume, other hospital characteristics, patient demographics, and patient health status. We tested for the endogeneity of hospital volume. DATA COLLECTION/EXTRACTION METHODS: A panel of two orthopaedic surgeons and two internists reviewed diagnosis codes to determine whether a complication was likely, possible, or due to anemia. After removing the few observations with bad or missing data, the final population has 295,473 observations. PRINCIPAL FINDINGS: The probability of a likely in-hospital complication declines rapidly from 53 through 107 operations per year, then levels off. Statistical tests imply that hospital volume is exogenous in this patient-level data. Complication rates increased steadily through the study period. Although obesity appeared to lower the probability of a complication, a counterintuitive result, further investigation revealed this to be an artifact of the claims data limit of listing no more than five diagnoses. Controlling for this restriction reversed the effect of obesity. CONCLUSIONS: Rather than uncontrolled expansion of knee surgery to small hospitals, decentralization to regional centers where at least about 50, and preferably about 100, operations per year are assured appears to be the optimal policy to reduce in-hospital complications.

Arthroplasty, Replacement, Knee↗