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D T Gray

Publications and source records attributed to D T Gray.

24 records · Page 2Linked to original sources
PubMed1994

Examination of the early 'learning curve' for transcatheter closure of patent ductus arteriosus using the Rashkind occluder. PDA Closure Comparative Study Group.

BACKGROUND: Results of transcatheter implantation of the Rashkind double umbrella occluder for treatment of patent ductus arteriosus (PDA) have improved over time. We evaluated factors associated with changes in outcomes seen in the early clinical experience with this device. METHODS AND RESULTS: We reviewed records of otherwise healthy pediatric patients undergoing occluder implantation for isolated PDA between 1982 and 1987 at six major US and Canadian referral centers. Logistic regression was used to assess the impact of ductal size, patient age and weight, calendar time, prior intrainstitutional occluder experience, and residual center effects on closure rates. There were no study deaths. Of 180 occluder placement attempts, 76.7% (95% confidence limits = 70.5%, 83.0%) produced PDA closure by auscultation at 14-month cardiology follow-up or its equivalent. Success probabilities increased in a linear fashion as ductus size decreased, ranging from 41.7% for large (4.1 to 9.0-mm) ducts to 89.4% for small (1.5 to 2.5-mm) lesions. PDA occluder closure rates also improved over time, increasing from 47.4% in 1982-1983 to 84.6% in 1986 and 83.1% in 1987. Multivariate logistic regression indicated that improved outcomes were mainly attributable to decrease in the size of treated ducts over time. Independent of this patient selection, improvements in outcome were less strongly associated with cumulative intracenter experience, calendar time, and age. CONCLUSIONS: Increasing closure rates seen over time primarily reflected more judicious selection of patients as experience accumulated. However, other factors also contributed to the observed trends. An analysis of current treatment results would be of considerable interest.

Age Factors↗
PubMed1993

Clinical outcomes and costs of transcatheter as compared with surgical closure of patent ductus arteriosus. The Patient Ductus Arteriosus Closure Comparative Study Group.

BACKGROUND: Transcatheter implantation of the Rashkind PDA occluder is an alternative to conventional surgical closure of isolated patent ductus arteriosus. Neither the clinical outcomes nor the costs of these procedures have been formally compared. METHODS: We performed a retrospective cohort study to evaluate the clinical outcomes within a seven-month period for comparable patients with patent ductus arteriosus who underwent either placement of an occluder or surgical closure. The patients were treated between 1982 and 1987 at 14 major North American centers where patent ductus arteriosus was closed predominantly by a surgical procedure or by the occluder technique. To estimate inpatient and follow-up costs, we multiplied the observed use of resources by 1989 unit costs based on hospital-accounting and physician-reimbursement data. RESULTS: On the basis of cardiac auscultation at follow-up, the initial procedure resulted in closure of the ductus arteriosus in 77.3 percent of 185 patients in whom the occluder was implanted (95 percent confidence interval, 70.6 to 83.1 percent) and 99.8 percent of 446 surgical patients (95 percent confidence interval, 98.8 to 100.0 percent). Second procedures increased the percentage of successful closures to 87.6 percent (95 percent confidence interval, 81.9 to 92.0 percent) and 100.0 percent (95 percent confidence interval, 99.3 to 100.0 percent) for patients in the occluder and surgical groups, respectively. There were no deaths. Major complications occurred in 2.7 percent of the patients in whom the occluder was implanted (95 percent confidence interval, 0.9 to 6.2 percent) and 0.2 percent of the patients who underwent surgery (95 percent confidence interval, 0.0 to 1.2 percent); moderate complications in 16.8 percent (95 percent confidence interval, 11.7 to 22.9 percent) and 15.0 percent (95 percent confidence interval, 11.8 to 18.7 percent), respectively; and minor complications in 11.4 percent (95 percent confidence interval, 7.2 to 16.8 percent) and 24.9 percent (95 percent confidence interval, 20.9 to 29.2 percent). Including the cost of follow-up care, the mean estimated cost per case treated surgically was $8,838 (in 1989 U.S. dollars), as compared with $11,466 per case treated with the occluder technique. Sensitivity analyses based on our data identified no plausible situations in which the costs of surgery and of implantation of the occluder would be equal. CONCLUSIONS: The more effective and less costly surgical procedure was superior to transcatheter placement of the occluder for closure of isolated patent ductus arteriosus. Consequently, our results do not support the wide-spread dissemination of the occluder procedure for the management of this common congenital lesion.

Cardiac Catheterization↗
PubMed1992

Economic analysis in randomized control trials.

In medical technology assessment, randomized control trials (RCTs) play an important role in determining the relative efficacy of compared treatments. As scarce resources necessitate choosing among options for care, comparing costs of alternative tests, treatments, or programs also becomes important. This study assessed the prevalence and completeness of economic analyses in RCTs published from January 1966 through June 1988. It was found that only 121 of over 50,000 published randomized trials (0.2%) included economic analyses. For a random sample of 51 of these 121 studies, results revealed a mean quality of research score of 0.32 (SD of measurement = 0.14) and a mean economic analysis completeness score of 0.52 (SD = 0.13) on scales of 0 to 1. It was also found that higher economic completeness scores were positively correlated with later dates of publication (r = 0.28, P = 0.046) and with the presence of a statement of study perspective (r = 0.38, P = 0.006). A near-zero correlation between the economic completeness and the quality of research scores was revealed. Also noted were several deficiencies among the economic analyses, including improper allocation of overhead costs, absence of sensitivity analyses, and the fact that only 28% of the 51 studies included some form of aggregation of treatment costs and consequences. Progress in health care depends on accurate assessments of both relative efficacy and costs. The quality of both needs improvement.

Cost-Benefit Analysis↗
PubMed1982

Early surgical excision versus conventional therapy in patients with 20 to 40 percent burns. A comparative study.

Using the records of 72 patients treated at the University of Washington Burn Center, this study compared the results of early surgical excision (by 14 days postburn) and autografting to those of autografting after spontaneous separation and bedside debridement of burn eschar. Excised patients had shorter hospitalizations and lower rates of burn wound sepsis and serious burn wound contamination, and less use of potentially toxic antibiotics (p less than 0.05) than did the prognostically equivalent group treated before the introduction of early excision. Excised patients required more blood transfusions (p less than 0.05), but did not differ significantly from controls in rates of mortality or other inpatient complications, in the number of operations performed, or in the adjusted hospital costs. Evaluation of patients treated over the entire study period for more shallow burns indicated no concurrent change in other aspects of burn care which might account for the observed results. We conclude that early excision and grafting in young, otherwise healthy patients with 20 to 40 percent total body surface area burns that are likely to heal within 3 weeks is more effective than the more traditional management of slow wound separation and debridement.

Adolescent↗
PubMedDate not supplied

Decision and cost-utility analyses of surgical versus transcatheter closure of patent ductus arteriosus: should you let a smile be your umbrella?

Decision and cost-utility analyses considered the tradeoffs of treating patent ductus arteriosus (PDA) using conventional surgery versus transcatheter implantation of the Rashkind occluder. Physicians and informed lay parents assigned utility scores to procedure success/complications combinations seen in prognostically similar pediatric patients with isolated PDA treated from 1982 to 1987. Utility scores multiplied by outcome frequencies from a comparative study generated expected utility values for the two approaches. Cost-utility analyses combined these results with simulated provider cost estimates from 1989. On a 0-100 scale (worst to best observed outcome), the median expected utility for surgery was 99.96, versus 98.88 for the occluder. Results of most sensitivity analyses also slightly favored surgery. Expected utility differences based on 1987 data were minimal. With a mean overall simulated cost of $8,838 vs $12,466 for the occluder, surgery was favored in most cost-utility analyses. Use of the inherently less invasive but less successful, more risky, and more costly occluder approach conferred no apparent net advantage in this study. Analyses of comparable current data would be informative.

Angioplasty↗