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Biomedical subjects

S Zuckerman

Publications and source records attributed to S Zuckerman.

At least 37 records · Page 2Linked to original sources

Health reform: the good, the bad, and the bottom line.

The Health Security Act is a pragmatic plan for achieving universal health insurance coverage for a broad package of benefits at reasonable cost. It proposes necessary and reasonable changes in insurance market practices and administrative structure. It finances the reformed system with a credible combination of achievable cost savings, mandatory private-sector payments, and limited "sin" taxes. Political constraints-the inability to tax openly or redistribute tax subsidies-result in weak incentives for consumers to choose low-cost plans and an inefficient scheme for providing subsidies to the poor. The act also unnecessarily restricts and regulates fee-for-service plans and the training of health workers. We propose changes to correct the act's weaknesses without compromising its basic objectives.

Community Participation↗

Strategies for implementing global budgets.

Implementing global budgets requires setting a desired level of spending as well as establishing a set of policies to assure the budget will be met. Four alternative approaches are analyzed: one relies on all-payer rate setting coupled with volume controls; the second is a system of premium regulation that controls both the levels and rates of insurance premium increase; in another system, price competition among insuring organizations limits growth in spending while incorporating a global budget that limits the aggregate costs of all premiums; finally, either managed competition or premium regulation is combined with all-payer rate setting. The fourth model is singled out for its ability to control costs. An independent policy toward capital expenditures could increase the likelihood of success under any of the strategies.

Budgets↗

Measuring prices of Medicare physician services.

This study develops two sets of price indices for Medicare physician services. The first measures price changes, and the second measures geographic price differentials. The indices can be used to adjust Medicare physician spending data to examine growth or variations in the volume and intensity of services. In both instances, it is necessary to apply an index form that reflects both the rapid changes and variability in the mix of physician services received by Medicare beneficiaries and their relative importance. This suggests that an index based on a fixed basket of services (e.g., a Laspeyres index) can produce a biased measure of price. An alternative methodology based on the Fisher's Ideal Index form was used. This index allows service weights to vary over time and across areas. In the case of price change, the index is "chained" to acknowledge the introduction of new services over several years. It is concluded that the Fisher's Ideal approach is essential for cross-sectional price comparisons, in light of the high variability in service mix across areas. In measuring price changes, it was found that "chaining" was more important empirically than allowing the relative importance of services to change between years. During the 1985-1989 study period, Medicare payment rates grew, on average, by 3.5% annually. This rate varied across both time and types of services as a result of differential fee updates and explicit pricing policies implemented by Medicare (e.g., reductions in payments for "overvalued" procedures). Cross-sectionally, our results show that 1988 fees in the highest-priced areas were more than 1.5 times those in the lowest-priced areas.

Abstracting and Indexing↗

FK506 measurement: comparison of different analytical methods.

In this study, we used solid-phase extraction with Sep-Pak and a liquid-liquid extraction with methylene chloride as two primary methods of extracting FK506 from plasma. The extracts were either analyzed directly by enzyme-linked immunosorbent assay (ELISA) or subjected to high-performance liquid chromatography (HPLC) separation and different fractions were analyzed by ELISA. Serial blood samples were obtained from four kidney transplant patients and four patients who underwent liver transplantation, from day 1 until day 30-35 posttransplantation. There was no significant difference in the FK506 plasma concentration as measured by all four methods in normal transplant patients. However, in liver transplant patients, the solid-phase extraction method gave higher FK506 concentrations than the methylene chloride extraction during the early postoperative period. The concentrations measured after methylene chloride extraction were higher than that after HPLC-ELISA. This higher FK506 concentration measured by direct ELISA could be attributed to possible cross-reacting metabolites that were present in the plasma of patients with abnormal liver functions. Once liver function returns to normal, all four methods give identical plasma concentrations for FK506.

Chemistry Techniques, Analytical↗

Cyclic nucleotides and cerebrovascular tone in newborn pigs.

Relationships between cyclic nucleotides and cerebrovascular tone were investigated using closed cranial windows in anesthetized newborn pigs. Pial arteriolar diameter was monitored and cerebrospinal fluid (CSF) was collected from beneath the cranial window. Adenosine 3',5'-cyclic monophosphate (cAMP) and guanosine 3',5'-cyclic monophosphate (cGMP) concentrations in CSF were 1,690 +/- 200 and 730 +/- 40 fmol/ml, respectively. Topically applied isozyme-selective and nonselective inhibitors [3-isobutyl-1-methylxanthine (IBMX), theophylline, Ro 201724, dipyridamole, zaprinast, calmidazolium, and W-7] of cyclic nucleotide phosphodiesterases dilated pial arterioles with concomitant increases in cAMP and/or cGMP levels in CSF. Topical application of dibutyryl-cAMP and dibutyryl-cGMP also resulted in pial arteriolar dilation. Ten-minute hypercapnia, which results in pial arteriolar dilation, increased cAMP to 5,240 +/- 900 and cGMP to 1,350 +/- 200 fmol/ml. IBMX and zaprinast potentiated the increases in cAMP and cGMP as well as the cerebrovascular dilation in response to hypercapnia. These data suggest that cyclic nucleotides contribute to regulation of cerebral vascular tone during control conditions. Furthermore, cAMP and/or cGMP appears to be involved in arterial vasodilation in response to hypercapnia in newborn pigs.

3',5'-Cyclic-AMP Phosphodiesterases↗

Effects of indomethacin on cerebral vasodilator responses to arachidonic acid and hypercapnia in newborn pigs.

Responses of pial arterioles to topically applied arachidonic acid, conversion of exogenous arachidonic acid to prostanoids, and pial arteriolar dilation to hypercapnia were examined before and at progressive times after treatment with indomethacin (5 mg/kg i.v.) in chloralose-anesthetized newborn pigs with closed cranial windows. Before treatment with indomethacin, arachidonic acid and hypercapnia dilated pial arterioles and increased cortical periarachnoid cerebrospinal fluid concentrations of 6-keto-prostaglandin (PG) F1 alpha and PGE2. One h after indomethacin treatment, the dilations and prostanoid synthesis were blocked. By 2 h after indomethacin treatment, hypercapnia produced significant dilation of pial arterioles, and dilation to both stimuli had returned to preindomethacin levels by 3 h. Inhibition of conversion of exogenous arachidonic acid to prostanoids as monitored by increases in 6-keto-PGF1 alpha and PGE2 in cerebrospinal fluid under the window also was reversed by 3 h after treatment with indomethacin. Repeated indomethacin treatment again blocked dilations and conversion of arachidonic acid to prostanoids on the brain surface. The possibility of short duration of vascular effectiveness of indomethacin when it is administered systemically needs to be considered, both when it is used as a probe for understanding contributions of PGH synthase products to control of cerebral circulation and when it is used therapeutically in attempts to alter the newborn cerebral circulation.

Animals↗

Cerebral blood flow decreased by adrenergic stimulation of cerebral vessels in anesthetized newborn pigs with traumatic brain injury.

Changes in cerebral blood flow (CBF), pial arteriolar diameter, and arterial blood pressure, gases, and pH were examined before and for 3 hours after fluid-percussion brain injury in alpha-chloralose-anesthetized piglets. The brain injury was induced by a percussion of 2.28 +/- 0.06 atm applied for 23.7 +/- 0.5 msec to the right parietal cortex. Regional CBF was measured with radiolabeled microspheres, and changes in pial arteriolar diameter were monitored in the left parietal cortex using closed cranial windows. Immediately following brain injury, mean blood pressure transiently (for approximately 10 minutes) either increased or decreased and then exhibited a prolonged decrease in all of the animals. The brains showed changes consistent with traumatic brain injury such as subarachnoid hemorrhage, contusions, or reactive axonal swelling; none showed histological evidence of a global alternative pathogenetic mechanism such as hypoxic ischemic damage. While CBF of uninjured control animals did not change over a 3-hour observation period, after brain injury blood flow decreased 30% +/- 1% below the baseline level within 10 minutes and remained there for 2 to 3 hours posttrauma. After adrenergic blockade, CBF did not decrease at any time during the 3-hour period in either the uninjured control or the injured animals. Concomitant with the decreased blood flow after brain injury, pial arteriolar diameter decreased 14% below the preinjury level. However, in piglets treated with adrenoceptor antagonists, uninjured control and brain-injured animals did not show a decrease in pial arteriolar diameter. The present results support the hypothesis that increased sympathetic outflow to the cephalic vasculature following the fluid-percussion brain injury causes cerebral vasoconstriction decreasing pial arteriolar diameter and regional CBF.

Adrenergic alpha-Antagonists↗

Pituitary adenylate cyclase-activating polypeptide dilates cerebral arterioles of newborn pigs.

The actions of the 38- and 27-amino acid forms of synthetic pituitary adenylate cyclase-activating polypeptide (PACAP-38 and PACAP-27) on cerebral arterioles were tested in anesthetized newborn pigs equipped with closed cranial windows. The diameter changes of pial arterioles to topical PACAP were measured and cortical periarachnoid cerebrospinal fluid samples were collected for measurement of cAMP. The 38- and 27-amino acid forms of PACAP produced similar dose-dependent vasodilations. The increases of pial arteriolar diameter produced by PACAP-38 were 6 +/- 1%, 15 +/- 2%, 23 +/- 3%, and 38 +/- 3%, and those produced by PACAP-27 were 6 +/- 1%, 15 +/- 2%, 27 +/- 5%, and 38 +/- 8% at 10((-9), 10(-8), 10(-7), and 10(-6) M, respectively. Arteriolar diameter began to increase 1-2 min and reached a maximum 6-8 min after topical application of PACAP. Vasoactive concentrations of PACAP-38 and PACAP-27 increased cerebrospinal fluid cAMP levels dose dependently. Thus, PACAP-38 and PACAP-27 appear to stimulate cerebral adenylate cyclase and are potent dilators of newborn pigs pial arterioles.

Animals↗

How do Medicare physician fees compare with private payers?

Under the new fee schedule, Medicare physician fees are 76 percent of private fees. Consistent with the intent of payment reform, Medicare physician fees more closely approximate private fees for visits (93 percent) than for surgery (51 percent) and in rural areas as compared with large metropolitan areas. Variation in private fees across the country is considerably greater than it is for Medicare fees. Consequently, Medicare fees are most generous in areas that compare least favorably with the private market because private fees in these areas are well above average. These results shed light on the impact of the fee schedule and on the implications of using Medicare payment methods as part of a broad-based health reform.

Data Interpretation, Statistical↗

Physician fee levels: Medicare versus Canada.

Adjusted for differences in purchasing power and practice expenses, Canadian physician fees are, on average, 59 percent of Medicare fees. The general perception that Medicare fees are low is the result of comparison with U.S. private fees, not to the much lower Canadian fees. In the context of the current U.S. health care system, lowering Medicare fees to Canadian levels could jeopardize access to care by Medicare beneficiaries. However, if all payers used the same fee schedule, fees that differed substantially from those currently used by private insurers might be viable.

Canada↗

Border crossing for physician services: implications for controlling expenditures.

In this article, the authors explore geographic border crossing for the use of Medicare physician services. Using data from the 1988 Part B Medicare Annual Data (BMAD) file, they find that there is substantial geographic variation across both States and urban and rural areas in border crossing to seek services. As might be expected, there is more border crossing among smaller geographic areas than among States. Predominantly rural areas tend to be major importers of services, but urban areas, on average, export services. Border crossing tends to be greater for high-technology services such as advanced imaging, cardiovascular surgery, and oncology procedures. These results suggest that expenditure-control policies applying to States or metropolitan areas should incorporate adjusters for patients' current geographic patterns of care.

Catchment Area, Health↗

The future of Medicare Volume Performance Standards.

A policy of Medicare Volume Performance Standards (MVPS) was established to control the rate of growth in Medicare physician spending. The standards control spending growth by lowering fee updates when spending exceeds a preset standard, or increasing updates when spending is below the standard. Separate standards are established for surgical and nonsurgical services. This paper examines the policy's weaknesses and proposes refinements that would enhance the equity of MVPS rewards and penalties, and therefore, the policy's long-term viability. Specifically, we suggest that MVPS policy permit differentials in standards across areas when utilization rates vary geographically and for some types of services when volume growth differs significantly.

Economics, Medical↗

The influence of opioids on local cerebral glucose utilization in the newborn pig.

Topical methionine enkephalin, leucine enkephalin, and dynorphin (10(-6)M) previously have been observed to produce prominent pial arteriolar dilation. Dilation to these opioids could be caused directly by opioids acting on vascular receptors, or indirectly, as a consequence of increased metabolism. Therefore, we examined this possibility by determining the influence of opioids on cerebral glucose utilization in piglets with closed cranial windows using the [14C]deoxyglucose method. Qualitatively, the autoradiographic images expressed as a change in relative optical density from vehicle were unchanged by these opioids. Quantitatively, the opioids similarly had no effect on cerebral glucose utilization (53 +/- 5, 70 +/- 8, 63 +/- 5, and 52 +/- 3, mumol.100 g-1.min-1 for vehicle, methionine enkephalin, leucine enkephalin, and dynorphin, respectively). In contrast, topical glutamate (10(-3) M) produced similar dilation but increased cerebral glucose utilization (41 +/- 3 vs 89 +/- 8 mumol.100 g-1.min-1 for vehicle and glutamate, respectively). Therefore, these opioids do not appear to produce vascular effects through a change in cerebral metabolic utilization of glucose.

Animals↗

Comparing physician fee schedules in Canada and the United States.

Although Canada and the United States have fundamentally different systems for financing health care, there are many similarities between the two countries in their approaches to physician payment. The similarities have increased recently with the adoption of the Medicare fee schedule. Canadian provinces have been using fee schedules for more than 20 years. This article provides an overview of the fee schedules used by Medicare and the four largest Canadian provinces, highlighting specific similarities and differences. We conclude that, although some differences in service definitions exist, the major areas of contrast relate to what services are paid for and how fees are updated. Updating fees is important because it affects how rapidly expenditures grow.

Canada↗

Measuring growth in the volume and intensity of Medicare physician services.

Congress adopted a policy of Volume Performance Standards that will adjust Medicare fees downward (or upward) in direct relation to the amount that spending exceeds (or falls below) a preset target. Using data from the 1985 through 1989 Medicare Part B Annual Data (BMAD), we show there are wide differences in the rate of growth in volume and intensity across types of services, specialties, and geographic areas. This suggests the current policy that bases adjustments on two national standards for surgical and nonsurgical services could lead to inequitable fee rewards and penalties. A greater number of targets based on more homogeneous service categories could reduce these inequities.

Cost Control↗

An American approach to health system reform.

In terms of the major objectives one would have for health system reform, this plan makes the following choices: 1. It would cover everyone, through Medicare (the elderly), employer-based coverage (some workers and dependents) or a state-level public program that would replace Medicaid (the poor, unemployed, and other workers and dependents). 2. There would be a standard minimum package of required benefits for employer-based and public programs, with legislative requirements on maximum cost-sharing. Choice of provider might be restricted in some states. 3. Administration of the private programs would be the responsibility, as now, of the employers and/or insurance companies. Administration of the public program would be the responsibility of the states, with the objective of maximizing responsiveness to local needs and conditions. 4. It would control costs through giving the states a substantial financial stake in ensuring that the public program costs did not grow faster than nominal GNP. State control would also allow the testing of different mechanisms for cost control, with the ultimate objective of identifying the most effective cost-containment strategies. 5. The cost would be borne by employers, employees, and taxpayers. Employers would be protected from exorbitant costs by being allowed the option of paying into a public plan rather than providing health insurance themselves. The poor and unemployed would be protected by having their coverage under the public program subsidized on a sliding scale. 6. The political feasibility test would be met by retaining a major role for insurance companies and by retaining the role of employer-based coverage--thus reducing the tax increase needed to ensure universal coverage. By allowing flexibility in design of cost-containment strategy, some of the controversy over this issue would also be deflected. Our proposal is also not without problems. First, our approach would still have adverse effects on the profitability of small businesses and on the employment prospects for low-wage workers--although these effects would be less than under conventional mandates and less than under proposals with higher tax rates. Second, some states may not want the responsibility we envision or have the capacity to carry it out. But several Canadian provinces are relatively small and are able to perform the same administrative functions within the Canadian national health system. In addition, since the federal government would continue to administer the Medicare program, states would have the option of tying their policies for hospital and physician payment and utilization control to those of Medicare.(ABSTRACT TRUNCATED AT 400 WORDS)

Canada↗

Effects of ischemia/reperfusion on brain tissue prostanoids and leukotrienes in newborn pigs.

We investigated the hypothesis that cerebral prostanoid and peptidoleukotriene (LTs) (LTC4/D4/E4/F4) synthesis are increased during postischemic reperfusion of newborn pig brains. Prostanoids and LTs extracted from brain tissue were determined by RIA in sham-control piglets and at 1h, 3h, or 12h after a 20-min period of total cerebral ischemia. During reperfusion following ischemia, all regional brain tissue (cerebrum, brain stem and cerebellum) prostanoids (6-keto-PGF1 alpha, TXB2, PGE2 and PGF2 alpha) were increased at 1h compared with those in sham-control piglets. Only cerebral and brain stem 6-keto-PGF1 alpha and cerebral TXB2 remained elevated at 3h postischemia and all prostanoids returned to control levels by 12h postischemia. Brain tissue LTs were lower than prostanoids and were not altered 1, 3, or 12h following ischemia. These data indicate that 1) newborn pig brain tissue prostanoids are increased initially, and then returned to control levels at later stages of reperfusion following ischemia; 2) LTs are present in newborn pig brain tissue, but are not increased by ischemia/reperfusion injury and therefore probably do not play a significant role in cerebral ischemia-reperfusion injury.

6-Ketoprostaglandin F1 alpha↗