Preserving the patient referral process in the managed care environment.

Referrals are a central component of the American health care system, defining the relationship among generalists, patients, and specialists. The dynamics of the referral process as they existed in a fee-for-service medical environment will evolve under managed care, but retain the basic "Try-out" approach of the generalist and "Rule-out" approach of the specialist. A managed care, contract-based health care system alters some of the assumptions on which the referral relationship has been structured. A four-step approach to assuring quality interactions among patient, generalist, and specialist within the managed care environment is described, including: (1) engage; (2) anticipate; (3) feedback; and (4) reassess. When the referral process is structured as suggested, it can be evaluated for quality and efficacy. Armed with mutual respect and understanding, the forces that polarized specialist and generalist care in the 1980s can be redirected to enhancing patient care in the 1990s.

Intraarterial hepatic chemotherapy with fluorouracil, fluorodeoxyuridine, mitomycin C, cisplatin or methotrexate as single-agent anticancer drugs for a transplanted experimental liver tumor in rats.

A prospective, controlled and standardized animal experiment was performed to study the influence of various anticancer drugs. The Novikoff hepatoma transplanted into male Sprague-Dawley rats was treated with fluorouracil (FUra), mitomycin C, methotrexate, cisplatin and fluorodeoxyuridine (FdUrd) at equi-effective dosage, in terms of side effects (weight loss), in comparison to a control group (0.9% saline solution) by locoregional application via the hepatic artery. The tumor multiplication factor (TMF = tumor volume day 12/tumor volume day 5) served as the parameter to compare the tumor growth of the various groups. All drugs showed a significant (P < 0.05) effect on the tumor growth. In comparison to the control group (mean TMF 9.66), FdUrd (3.78) and FUra (3.03) only limited the tumor growth, mitomycin C (0.96) produced stable tumor, cisplatin (0.64) and methotrexate (0.15) significantly reduced (P < 0.01) the tumor size. We suggest that, in addition to the established (FUra, FdUrd, mitomycin C) drugs, methotrexate and cisplatin should be considered in further studies of the treatment of primary and secondary liver malignancies.

[Results of devascularization surgery of the gastroesophageal junction in recurrent hemorrhage of esophageal and fundus varices]. / Ergebnisse der Devaskularisationsoperation des gastroösophagealen Uberganges bei Rezidivblutungen aus Osophagus- und Fundusvarizen.

Bleeding esophageal and gastric varices caused by portal hypertension with (group I) or without (group II) liver damage should be treated primarily by sclerotherapy or shunt-operation if there is no indication for liver transplantation. In the case of rebleeding associated with thrombosis of portal-/mesenteric or splenic vein we performed in 17 patients a complete devascularisation of the proximal stomach, cardia and distal esophagus (Hassab's operation 1967) (N = 5--group I; N = 12--group II). In group I, the early postoperative (0-30 days p.o.) course was complicated by one necrosis of the gastric fundus. In group II, postoperative bleeding from gastric varices was noted in four patients, three of which were treated by proximal gastric resection; two of twelve patients died. No serious complications in the long-term follow-up (min. 171--max. 1217 days) occurred in group I. In group II, half of the patients died (1 bleeding episode, 1 liver coma, 1 hepatocellular carcinoma, 2 other causes). The operative risk and the long-term prognosis are essentially influenced by the basic disease and to a much lesser degree by the type of operation. The devascularisation of the esophago-gastric junction is per se a low risk intervention which is always practicable, even in high risk patients.

Isolation of human colonic crypts for study of xenobiotics metabolism.

Methods allowing study of human colonic drug and carcinogen metabolism in intact epithelial preparations in vitro are needed. We describe an isolation method yielding intact colonic crypts with well-maintained ultrastructural integrity and good viability parameters. The crypt preparations obtained with this method were used to study phase I and II drug biotransformation. The colonic crypts demethylated aminopyrine and nitrosodimethylamine slowly, but the colonic carcinogen dimethylhydrazine at a higher rate. The phenolic compounds estrone, 17 beta-estradiol, and 1-naphthol were readily conjugated. In conclusion, the present method yields preparations well suited for further investigation of the role of human colonic biotransformation in carcinogenesis and drug pharmacokinetics.

Arterial, portal or combined arterio-portal regional chemotherapy in experimental liver tumours?

The most appropriate route for regional administration of chemotherapeutic drugs to liver tumours was studied in a standardized rodent model: cells of Novikoff hepatoma were transplanted into the central liver lobe of Sprague-Dawley rats. From day 5 to day 12 after transplantation, the liver was continuously perfused with 420 mg/kg 5'-fluoro-2-deoxyuridine by subcutaneous osmotic micropumps via the hepatic artery (n = 20), the portal vein (n = 20) or both vessels together (n = 12). The tumour multiplication factor (TMF) and the vascularization of the tumour were evaluated. Arterial and combined infusion led to a highly significant reduction in TMF, but combined infusion was not more effective than arterial alone. Portal infusion had no significant effect. There was no correlation between vascularization and tumour response in arterial infusion, but a strong correlation in portal infusion. Thus chemotherapy via the portal route may be effective in selected tumours with considerable portal vascularisation.

Teaching preventive cardiology in the pediatric setting.

This article presents both the rationale behind and a framework for incorporating pediatric preventive cardiology into undergraduate medical education and pediatric residency training. Such education of physicians in the practice of preventive cardiology requires provision of not only didactic information but also training and practice in clinical skills. A combination of didactic lectures, small group discussions, interactive programs utilizing video tapes and computer programs, family and patient simulation, preventive cardiology clinics, and community cardiovascular health promotion activities all help to provide the optimal framework for an effective medical student and pediatric resident training program in pediatric preventive cardiology. Since pediatricians are in the best position to practice true primary prevention of cardiovascular disease beginning in childhood, it is essential that physicians in training understand the concepts and learn the skills needed to practice this critical component of pediatric medicine.

[Celiac artery compression syndrome]. / Das Art. coeliaca-Kompressionssyndrom.

External compression and kinking of the celiac axis is caused by the enlarged and fibrous median arcuate ligament of the diaphragm. The pathogenetic cause may be a functional ischemia or an irritation of the squeezed celiac ganglion. This painful syndrome is an unusual condition, which occurs at a maximum age of about 40 years and mostly in women. The diagnosis is established by exclusion of all other abdominal sources of pain and lateral aortography. The therapy can often be limited to longitudinal incision of the ligament; reconstructive procedures of the coeliac artery are sometimes necessary.

Attitudes toward prevention of cardiovascular diseases among first-year students at eight American medical schools, 1983-1985.

First-year medical students at eight U.S. medical schools were surveyed by written questionnaire in 1983-1985 to determine their attitudes toward cardiovascular diseases prevention at medical school entry. An overall response rate of 92% was achieved (2,654 questionnaires), and 97% of responders provided complete and analyzable survey data. Response rates at five of eight medical schools were 98-100%, and one school each had rates of 67, 84, or 90%. Differences in mean attitude responses from school to school were small, as were differences between men and women or between blacks and whites. This survey found that entering medical students have generally positive attitudes toward the effectiveness of preventive cardiology practice as well as toward the importance of research efforts in cardiovascular disease prevention. Students frequently indicated, however, that it is "extremely difficult" to change patients' unhealthful habits and that "physician encouragement" may not be sufficient to help patients achieve more healthful behaviors. These findings could be helpful in directing educational efforts for medical students. The data suggest that major emphasis should be placed on conveying facts regarding the physicians' efficacy in clinical preventive cardiology and on teaching the skills of preventive cardiology practice. Less emphasis appears to be necessary on encouraging positive attitudes about the importance of prevention since current students' attitudes appear to be already positive in this dimension.

Continuous or bolus chemotherapy with 5-fluoro-2'-deoxyuridine in transplanted experimental liver tumors?

The effect of continuous and discontinuous locoregional chemotherapy with Floxuridine (FUdR) was studied in a standardized and controlled animal model, using the transplantable Novikoff hepatoma in Sprague-Dawley rats. The liver was perfused after transplantation with a total of 420 mg/kg FUdR, via a fully implanted osmotic minipump or miniport and catheter in the hepatic artery, either continuously (n = 22) from day 5 to day 12, or discontinuously (n = 28) on days 5 and 8. Viable tumor volume and peritumorous cell infiltration were measured. No reduction in tumor volume was attained using discontinuous therapy, in contrast to a highly significant reduction using continuous therapy (P less than 0.001). Significantly less cell infiltration was found after discontinuous than after continuous therapy. In conclusion, continuous locoregional chemotherapy with FUdR was the superior administration method on measurable tumor effect, when compared to discontinuous infusion.

[Are there differences in prodromal illnesses, symptoms and prognosis for various forms of mesenteric infarct?]. / Existieren Unterschiede bei Vorerkrankungen, Symptomatik, und Prognose für die verschiedenen Formen des Mesenterialinfarktes?

Comparing 105 patients with mesenteric infarction, the typical attributes of the underlying diseases, arterial embolization (aE) (n = 26), arterial thrombosis (aT) (n = 40), venous thrombosis (vT) (n = 32) and combined arterio-venous occlusion (n = 7) could be demonstrated. Present heart disease, diabetes and arterial hypertonia, rapid onset of symptoms, severe abdominal pain and signs of peritonitis, extended gangrene of bowel and a high mortality of about 90% is the typical combination for aE. Over 70 years old patients with higher incidence of arteriosclerosis, more digitalis intake, longer duration of symptoms and with bowel problems in the past have a higher incidence of aT and a slightly better prognosis. Risk of thrombosis, long-standing symptoms and a clearly better prognosis are typical for the vT.

Hemodynamic responses of the acutely stressed neonatal right ventricle: a maturational study in lambs.

Right ventricular Starling responses to acute volume infusion in newborn lambs were compared to those in older groups of lambs. When peak stroke volume/kg was reached during infusion, right ventricular end-diastolic pressures for the newborn group were significantly lower (p less than 0.001) than those obtained for older groups, in spite of significantly higher resting and peak stroke volumes in the two younger groups. Newborn lambs developed tricuspid regurgitation and right-to-left foraminal shunting, demonstrated by echocardiography, at a mean end-diastolic pressure of 7.5 mm Hg. No right-to-left shunting was noted in older lambs. This study demonstrated a blunted Starling response in the newborn lamb's right ventricle. The response to volume loading improved with maturation, but was still less than that reported for the left ventricle. Clinical implications regarding right ventricular immaturity and inadequate response to altered hemodynamic situations are raised.

Maturational changes in myocardial pump performance in newborn lambs.

We examined the left ventricular stroke volume response to fluid loading in 24 acutely instrumented newborn lambs and the right ventricular response in 12 lambs. Newborn lambs (group 1, ages 2 to 4 days) demonstrated a limited response to acute volume loading for both left and right ventricles. With maturation, the left ventricle exhibited a progressively greater ability to respond to acute volume loading, with greater peak stroke volumes achieved at higher end-diastolic pressures. The response of the right ventricle remained limited at all ages examined, with peak stroke volume achieved at lower end-diastolic pressures. We conclude that postnatal maturation of the left ventricle results in a progressively greater stroke volume response in older lambs, while the response of the right ventricle remains limited.

Conduction abnormalities detected by electrophysiologic testing following repair of ostium primum atrioventricular septal defect.

Since 1983 we have performed electrophysiologic studies in 6 patients who had previously undergone repair of an ostium primum atrioventricular septal defect. Information obtained during electrophysiologic studies was crucial in guiding appropriate pacemaker therapy in these patients. As judged from the resting electrocardiogram, sinus or junctional bradycardia was present in 3/6, atrial flutter / fibrillation in 2/6, and paced rhythm in 2 patients who had had ventricular pacemakers implanted for complete atrioventricular block. During maximal exercise testing 4 patients had reduced heart rates; 2 had sudden drops in heart rate at 1 min postexercise; 1 patient had exercise induced ventricular bigeminy; and 1 patient with atrial flutter and 2: 1-4: 1 block at rest developed 1: 1 conduction during Stage II with an effective ventricular rate of 220/min. During electrophysiologic studies, the maximum corrected sinus node recovery time was abnormal in five of the six, ranging from 410 to 5630 msec. There was no spontaneous atrial rhythm in the other patient. Complete atrioventricular block was present in 2 patients while the atrioventricular Wenckebach phenomenon occurred abnormally at atrial pacing cycle lengths greater than 450 msec in 2 others. Supraventricular tachycardia or atrial flutter/fibrillation, was either spontaneous or induced in 2/6 patients, while ventricular tachycardia was induced in 1/3 patients who underwent programmed ventricular stimulation. Electrophysiologic studies were important in unmasking severe sinus node disease in 3 patients and atrioventricular node disease in 2. We therefore recommend that electrophysiologic studies be strongly considered as part of the evaluation of conduction abnormalities following repair of ostium primum atrioventricular septal defect.

[Microsurgical bile duct anastomosis: animal experiment and clinical study]. / Die mikrochirurgische Gallengangsanastomose: Tierexperimentelle und klinische Untersuchung.

In 10 Göttingen-minipigs an end-to-end anastomosis of the normal common bile duct was accomplished under the microscope with 11/0 Polygalactin-sutures. Biliary flow was controlled by serum concentration of alkaline phosphatase, by cholangiography and by dynamic hepato-biliary scintigraphy 2 weeks, and 3 and 6 months after the operation. Anastomoses were judged by macroscopic, microscopic and scanning electronmicroscopic examination 6 or 12 months postoperatively. The anastomoses presented no stenosis at all, only a light periductal fibrosis with intact luminal epithelium. Alkaline phosphatases and cholangiography showed a normal pattern, the scintigraphy presented dyskinesia after 2 weeks and normal flow at the later controls. After a microsurgical operation one patient showed a normal anastomosis after 6 months. A biliary anastomosis should be made by microscope in all patients with a long life span and unchanged bile duct wall in spite of the more difficult operation.

A 20-year review of ostium primum defect repair in children.

Between July, 1963, and July, 1983, a total of 69 patients (35 boys and 34 girls) underwent ostium primum defect repair. There were four perioperative deaths and four patients were subsequently lost to follow-up, leaving 61 children followed for 6 months to 20 years (mean 5 years). Results of surgery were assessed by cardiac catheterization in 17 of 61 patients, while the remaining patients were evaluated noninvasively. Postoperative mitral insufficiency was found to be absent in 19 patients, mild to trivial in 35, moderate in four, and severe in two. Four patients were found to have large residual atrial septal defects. Significant late postoperative arrhythmias were found in 14 of 61 patients. The types of arrhythmias included isolated complete atrioventricular block in 5 of 14, complete atrioventricular block with sinus node dysfunction in 2 of 14, and isolated sinus node dysfunction in 7 of 14. Pacemakers have been implanted in 8 of 14 of these patients. Based on this 20-year review of a large number of children: (1) ostium primum defect repair is associated with a low mortality rate, (2) residual mitral insufficiency although common is usually mild to trivial and nonprogressive, and (3) significant arrhythmias are a frequent complication and often require pacemaker implantation.