William W. Coon

Venous Thromboembolism and Other Venous Disease in the Tecumseh Community Health Study

The prevalence and incidence of venous thromboembolism and other venous disease has been determined as part of a longitudinal study of health and disease in a Michigan community. When these data are extrapolated to 1970 U.S. census figures, a rough estimate of annual incidence of clinically recognized deep venous thrombosis is over 250,000 cases while that of superficial thrombophlebitis is over 123,000. An estimated 24 million US citizens have “significant” varicose veins while 6 to 7 million have stasis changes in the skin of the legs and 400,000 to 500,000 have or have had a varicose ulcer. The relatively high frequency of these conditions in the adult population of Tecumseh, Michigan, indicates that they represent several of the more common medical problems encountered by the practicing physician.

Epidemiology of venous thromboembolism.

This review of the epidemiology of venous thromboembolism includes estimates of incidence and prevalence of venous thrombosis and its sequelae, a discussion of geographical, annual and seasonal variations and data concerning possible risk factors. Selection of patients at increased risk for development of deep venous thrombosis or pulmonary embolism for specific diagnostic screening or for prophylactic therapy with low-dose heparin may be a more effective approach to lowering morbidity and mortality from this disease.

Deep venous thrombosis and pulmonary embolism: Prediction, prevention and treatment∗

Abstract The manifestations of thromboembolism are highly variable and frequently obscure. Clinical diagnosis of these entities is difficult, and the majority of cases will not be diagnosed by the means presently available to us. Nevertheless, a heightened awareness of the vagaries of this disease can result in considerable improvement in diagnostic accuracy. Prompt diagnosis on the basis of the slightest clinical suspicion, followed by immediate and adequate anticoagulant therapy, should result in a measureable decrease in thromboembolic complications. However, if one hopes to achieve a profound reduction in incidence of thromboembolism, the only approach presently available is prophylactic rather than therapeutic. The use of measures to increase venous return in patients who are immobilized in bed, plus the institution of prophylactic anticoagulant therapy in a selected group of patients with a high predisposition to the development of thromboembolic diseases, should result in a significant reduction in disability and mortality from this theoretically preventable disease.

Diagnosis of isolated small bowel injury following blunt abdominal trauma

A review of the case histories of 29 patients with isolated rupture of the small bowel was undertaken to determine which diagnostic tests were most sensitive in the early diagnosis of this notoriously occult injury. Results indicate that peritoneal lavage was the most useful test for this purpose, clearly more sensitive than standard clinical or radiographic signs. All patients in this series had indications for peritoneal lavage, and 85% of the patients who underwent peritoneal lavage in the emergency department had positive results and prompt operation. Reliance on the development of clinical peritonitis or the detection of pneumoperitoneum leads to long delays before operation.

Altered clearance of free amino acids from plasma of patients with cirrhosis of the liver

Summary Oral feeding of an egg-protein mixture or infusion of a balanced solution of essential amino acids to well-compensated cirrhotic patients is followed by a significant change in the rate of clearance of several amino acids from the plasma. This pattern is unchanged following portacaval shunt. The increased clearance of branched-chain amino acids and threonine may be secondary to a relative or absolute deficiency of these essential “building blocks” of protein in the cirrhotic patient.

Free amino acids in liver, plasma, and muscle of patients with cirrhosis of the liver☆

Abstract A significant decrease in concentration of branched-chain amino acids in skeletal muscle of cirrhotic patients has been observed. These data are presented in further support of the concept that a relative deficiency of these amino acids may be present in cirrhotic patients.

Some aspects of the pharmacology of oral anticoagulants

The pharmacology of oral anticoagulants ls discussed with particular rejerence to data of value in the management of therapy. The importance of individual variability in response and drug interaction is stressed. Other effects of these agents which may have clinical utility are noted.

Iatrogenic splenic injury.

In a previous report from this institution, 21% of splenectomies performed between 1957 and 1967 were for iatrogenic injury to the spleen. In the present study, encompassing the years 1971 to 1987, the frequency of iatrogenic splenic injury was reduced to 9% (134 of 1,557 splenectomies). However, there has been no evidence of a progressive decrease in accidental splenic injury from 1971 to 1987. Although the number of injuries related to operations on the stomach or repair of hiatus hernia have declined somewhat in the past decade, the incidence of splenic injuries secondary to colectomy and nephrectomy has not changed appreciably, and injuries linked to complex operations on the aorta and its branches (19 cases) have increased. No evidence could be found that morbidity was increased if the splenic injury is promptly recognized and managed by splenectomy. However, 13 of these 134 patients required reoperation for control of continued bleeding from unrecognized iatrogenic splenic trauma. Constant awareness of the continued prevalence of this operative complication and the mechanisms by which it is produced should enable surgeons to lessen its frequency and potential sequelae.

Splenectomy for cytopenias associated with systemic lupus erythematosus

Splenectomy was performed in 20 patients with refractory cytopenias associated with systemic lupus erythematosus. An immediate and sustained increase in platelet count (greater than 150,000 cells/mm3) was achieved in 12 of 18 patients whose principal indication for operation was thrombocytopenia. Of seven patients with hemolytic anemia, which was linked with thrombocytopenia in five, six had an increase in the hematocrit value of 20 percent or more after operation. The white blood count increased to normal values in three leukopenic patients. We believe that although removal of the spleen is not uniformly successful in correcting cytopenias in patients with systemic lupus erythematosus, splenectomy should be considered in patients refractory to other modalities of treatment.

Intra-individual and inter-individual variations in plasma free amino acids in normal adults

Summary Over periods of several months three serial determinations of plasma free amino acids have been performed in each of 14 individuals. Large intra-individual variations in levels of most of these amino acids were observed. Since normal values for each plasma free amino acid may vary as much as twofold or more among individuals, any study of plasma free amino acids in groups of patients must encompass a large population sample, unless profound differences from normal exist. Other considerations in experimental design of a study of this type have been discussed. Although the concept of biochemical individuality holds for all the amino acids except lysine and phenylalanine, it is diluted in importance by the large intra-individual variations observed.