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N Smithline

Publications and source records attributed to N Smithline.

9 recordsLinked to original sources

Increased costs and rates of use in the California workers' compensation system as a result of self-referral by physicians.

BACKGROUND: There is widespread concern that ownership by physicians of testing or treatment facilities to which they refer patients leads to overuse of such facilities. We determined the patterns of use of three services--physical therapy, psychiatric evaluation, and magnetic resonance imaging (MRI)--among physicians treating patients whose care was covered under workers' compensation. We then compared the rates of use among physicians who referred patients to facilities of which they were owners (self-referral group) with the rates among physicians who referred patients to independent facilities (independent-referral group). METHODS: We used a large data base to analyze claims under workers' compensation in California from October 1, 1990, through June 30, 1991, to determine the frequency and cost of these three selected services and determined whether the referring physicians were practicing self-referral or independent referral. We evaluated the cost per case for all three services, measured the frequency with which physical therapy was initiated, and evaluated the medical appropriateness of MRI. RESULTS: We found that physical therapy was initiated 2.3 times more often by the physicians in the self-referral group (68 percent) than by those in the independent-referral group (30 percent; P < 0.01). The mean cost per case for physical therapy was significantly lower in the self-referral group ($404 +/- 102) than in the independent-referral group ($440 +/- 167; P < 0.01). The mean cost of psychiatric evaluation services was significantly higher in the self-referral group than in the independent-referral group (psychometric testing, $1,165 +/- 728 vs. $870 +/- 482; P < 0.01, psychiatric evaluation reports, $2,056 +/- 1,063 vs. $1,680 +/- 578; P < 0.01). The total cost per case of psychiatric evaluation services was 26.3 percent higher in the self-referral group ($3,222 +/- 1,451) than in the independent-referral group ($2,550 +/- 742; P < 0.01). Of all the MRI scans requested by the self-referring physicians, 38 percent were found to be medically inappropriate, as compared with 28 percent of those requested by physicians in the independent-referral group (P < 0.05). There was no significant difference in the cost per case between the two groups. CONCLUSIONS: This study demonstrates that self-referral increases the cost of medical care covered by workers' compensation for each of the three types of service studied.

Ambulatory Care Facilities

Fulminant hepatic failure secondary to amebic abscesses.

A patient presented with fulminant hepatic failure which rapidly led to his death. At postmortem examination, he had several amebic abscesses secondarily infected with bacteria, one of which had ruptured intraperitoneally, and another of which had occluded major hepatic veins of the right lobe of the liver. In addition, pylephlebitis and occlusion of several right portal venous radicles were noted. Microscopic examination of the right lobe revealed marked sinusoidal congestion and large areas of infarction with severe panlobular necrosis. Fulminant hepatic failure secondary to complications of amebic abscess has been reported infrequently but should be considered in patients with this presentation who have visited or inhabited areas endemic for amebiasis.

Acute Disease

Evidence that alterations in distal sodium delivery and distal sodium avidity affect the rate of excretion of an acute HCl load.

In these experiments, two groups of animals were studies to evaluate the effect of altering renal tubular sodium-handling on the excretion of acute HCl load. In group, I, normal salt animals hypotonically expanded with antidiuretic hormone (ADH) (using a protocol known to stimulate aldosterone) presented large amounts of sodium to the distal tubule and excreted an acute HCl load much more efficiently than did animals pretreated with either a normal (NL) or low (LO) salt diet alone. In group II, 24 hr after acid-loading, the plasma bicarbonate concentrations were significantly lower in animals pretreated with sodium restriction plus furosemide (F) than in those maintained on a normal (NL) or high (HI) salt diet alone. Acid excretion was maximized (ADH) when distal sodium avidity was stimulated in the presence of adequate distal sodium delivery and minimized (F) when distal sodium delivery was limited (despite possible augmentation of distal sodium avidity). Alterations in urinary sodium excretion alone (LO, NL, HI) did not affect the rate of acid excretion. These data are compatible with the hypothesis that the excretion of an acute HCl load is mediated by existing levels of distal sodium delivery and distal sodium avidity.

Absorption

Prognosis in steroid-treated idiopathic nephrotic syndrome in adults. Analysis of major predictive factors after ten-year follow-up.

This long-term study analyzes the prognostic value of the quantitative urinary protein excretion during and following steroid administration, the renal functional status three years after the onset of disease, and the degree of histologic damage in adult patients with steroid-treated idiopathic nephrotic syndrome (INS). No patient who had a complete (proteinuria less than 0.1 gm/day) or partial (proteinuria less than 2.0 gm/day) remission during steroid administration progressed to renal failure. Furthermore, no patient in whom urinary protein excretion subsequently fell to below 2.0 gm/day ever progressed to renal failure. Only 3 of 49 patients in whom renal function was normal three years after the onset of INS developed renal failure. Finally, renal failure occurred in only 2 of 28 patients with mild abnormalities by light microscopy, compared with 12 of 21 patients with more advanced glomerular abnormalities. Thus, a partial, as well as a complete remission during steroid administration, subsequent reduction in proteinuria to below 2 gm/day, persistence of normal renal function beyond three years, or the presence of mild histologic abnormalities auger a favorable long-term prognosis in patients with INS.

Adolescent

Gaps--anionic and osmolal.

Gaps is a bedside diagnostic game. It is played in two versions by nephrologists. It deserves wider application by the practicing physician. The more popular version, Anion Gaps, shows the presence of undetermined anions and alerts the physician to the possibilities of laboratory error, severe derangements in serum protein metabolism, or the ingestion of certain ionic compounds that directly or indirectly alter the concentration of routinely undetermined anions. A second version, Osmolal Gaps, shows the presence of unmeasured osmoles or of increased plasma solids and can be used in a variety of clinical situations to direct attention to laboratory, error, hyperproteinemia, hyperlipidemia, or the presence of unmeasured osmoles in the serum.

Acidosis, Respiratory

Light-chain nephropathy. Renal tubular dysfunction associated with light-chain proteinuria.

We observed idiopathic light-chain proteinuria in a patient with multiple abnormalities of proximal-tubule transport mechanisms (Fanconi syndrome), nephrogenic diabetes insipidus, and distal renal tubular acidosis. Seventeen of the 19 urinary amino acid levels measured were elevated. Uric acid and phosphate clearances were greater than 60 per cent and 50 per cent, respectively, of the simultaneous inulin clearance. When water deprivation was coupled with vasopressin administration, the maximum urinary concentration observed was 384 mOsm per kilogram of water. During ammonium-chloride loading, the level of hydrogen-ion concentration in the urine remained less than 100 times that in the blood. Kappa light-chain excretion was 149 mg per 24 hours. It appears that the concurrence of proximal tubular dysfunction, distal tubular dysfunction and light-chain proteinuria represents a distinct syndrome, which we call "combined light-chain nephropathy." Available evidence indicates that excessive light-chain production with subsequent filtration, reabsorption and catabolism, causes the complex tubular dysfunctions observed.

Acidosis, Renal Tubular

The critical role of the adrenal gland in the renal regulation of acid-base equilibrium during chronic hypotonic expansion. Evidence that chronic hyponatremia is a potent stimulus to aldosterone secretion.

Recent studies have shown that chronic hypotonic volume expansion (HVE) induced by administration of vasopressin and water stimulates distal hydrogen ion secretion and thereby (a) permits dogs with HCl-acidosis to restore acid-base equilibrium to normal despite continued acid feeding and (b) permits normal dogs to conserve filtered bicarbonate quantitatively despite the natriuresis induced by water retention. To examine whether these effects of chronic HVE are mediated by augmented mineralocorticoid secretion, urinary and plasma aldosterone levels were monitored during prolonged administration of vasopressin. In HCl-fed animals, the HVE-induced rise in plasma [HCO3] (from 13.8 to 21.3 meq/liter) was associated with a rise in aldosterone excretion from 0.45 to 0.88 mug/day (P less than 0.02). In normal animals, in which plasma [HCO3] remained stable during HVE (21.9 vs. 20.0 meq/liter), aldosterone excretion rose from 0.51 to 2.28 mug/day (P less than 0.02) and plasma aldosterone concentration rose from 8.1 to 39.8 ng/100 ml (P less than 0.01). Vasopressin and water were also administered to adrenalectomized animals maintained on glucocorticoids and a slightly subphysiologic replacement schedule of mineralocorticoids. In the HCl-fed adrenalectomized group, plasma [HCO3], instead of rising to normal, showed no significant change (16.9 vs. 15.0 meq/liter). In the non-HCl-fed adrenalectomized group, plasma [HCO3], rather than remaining stable, fell significantly (20.3 vs 16.5 meq/liter, P less than 0.1). Two conclusions can be drawn from this study: (a) the well-known inhibitory effect of volume expansion on aldosterone secretion can be overridden by a potent stimulatory effect on the adrenal produced by severe chronic hypotonicity, and (b) the response of plasma [HCO3] observed during severe chronic HVE is mediated by augmented mineralocorticoid secretion. These findings, furthermore, offer a possible explanation for the puzzling observation that plasma [HCO3] in patients with the syndrome of inappropriate antidiuretic hormone secretion is maintained at normal levels even in the face of severe hyponatremia.

Acid-Base Equilibrium

Understanding acid-base disturbances.

The physiologic principles of blood pH, Pco2, and bicarbonate homeostasis provide a suitable basis for a systematic approach to the interpretation of acid-base disturbances. Pathogenesis, diagnosis, and management of the four classic acid-base disorders follows.

Acid-Base Imbalance