Prophylactic placement of vena caval filters: A cautionary note

Greenfield filter placement in patients without deep venous thrombosis has been performed when such patients were felt to be at high risk for asymptomatic deep venous thrombosis and subsequent embolus. In this group placement is termed truly prophylactic to differentiate from placement in a patient with documented deep venous thrombosis which has not yet embolized. A retrospective review of Greenfield filter placement at five Dayton, Ohio, community hospitals over three years revealed 59 filters placed in 58 patients. Of these 90% were placed surgically and 10% percutaneously at an average cost of $4,141.00 per surgical procedure. Indications included traditional as well as true prophylaxis. A low morbidity and no mortality related to filter placement was observed. The high efficacy and safety of filter placement seen at large institutions is also found in our community hospital experience despite placement by physicians who perform the procedure infrequently. Although filter placement in patients at a high risk for silent fatal pulmonary emboli may prevent a rare mortality, widespread use of this modality for pulmonary embolus prophylaxis is costly and not without patient risk. We caution against the use of Greenfield filters for pulmonary embolus prophylaxis in patients without deep venous thrombosis until evidence of superior efficacy compared to other forms of prophylaxis can be demonstrated. Presented at the Annual Meeting of the Peripheral Vascular Surgery Society, New York, New York, June 17, 1989. The opinions expressed herein are those of the authors and do not reflect the opinions of the United States Air Force or the Department of Defense.     

Airway management: A new look at old models

Two methods for modifying standard orotracheal intubation models, in order to teach and practice special airway management skills, are described. Using these quick and inexpensive manipulations, an intubation manikin can be modified for use as a teaching model for standard nasotracheal intubation techniques as well as both orotracheal and nasotracheal intubation with a lighted stylet.     

Ultrastructure of the Lungs of Dogs Exposed to Beryllium-Containing Dusts

Two beagle dogs were exposed by the natural respiratory route to rocket exhaust fumes containing beryllium oxide, beryllium fluoride, and beryllium chloride. The lung tissue was examined electron microscopically after a three-year post- exposure period. Beryllium particles and small agglomerates less than 1μ in size were deposited in iysosomes in the cytoplasm of histiocytes in the interstitium of the septa. They were closely associated with collagen bundles several microns wide and with increases in numbers of septal capillaries. The lesions were more typical of the classical reaction to a foreign-body than immunologic in character and represented an early form of chronic beryllium disease.     

Perianal Bowen's disease

Thirty-three patients with perianal Bowen's disease were treated at the Cleveland Clinic Foundation from 1954 to 1986. Twenty-one patients were women and 12 were men, ranging in age from 30 to 69 years (mean, 48 years). Twenty patients (61 percent) presented with symptomatic perianal disease, while 13 patients (39 percent) were noted as having perianal Bowen's disease upon pathologic examination of routine hemorrhoidectomy specimens. Ten of the patients (30 percent) had prior histories of unrelated cancer. Twenty-seven patients were managed by wide local excision, three patients by simple excision, three patients by fulguration, and one patient by an abdominoperineal resection. During a follow-up period averaging 3.7 years (range, 0.3 to 10 years), one patient developed a new invasive skin cancer while a second patient experienced a recurrence of perianal Bowen's disease. The characteristic gross appearance of this lesion and its failure to respond to conventional therapy should prompt the performance of a hiopsy, which readily establishes the diagnosis. This experience confirms that wide local excision is adequate therapy for perianal Bowen's disease and that close clinical follow-up is necessary to identify disease recurrence or the development of a malignancy. Poster presentation at the meeting of the American Society of Colon and Rectal Surgeons, Washington, D.C., April 5 to 10, 1987. The opinions experessed are those of the authors and do not reflect the opinions of the United States Air Force or the Department of Defense.     

Epidemiologic study of asymptomatic men screened by maximal treadmill testing for latent coronary artery disease

A group of 1,390 asymptomatic men screened for latent coronary artery disease by maximal treadmill testing and double Master two-step test were followed up for a mean of 6.3 years. Angina, sudden death or acute myocardial infarction was used as the end point for coronary heart disease. There were differences in testing sensitivity and specificity among age and subject groups, but maximal treadmill testing out-performed the double Master test as a screening technique. Maximal treadmill testing demonstrated a 60.9 percent sensitivity, 92 percent specificity and a 20 percent probability that coronary artery disease would develop in a subject with an abnormal response. A risk ratio of 14.3 was obtained and demonstrated that maximal treadmill testing was a valuable screening technique for latent coronary artery disease. However, limitations of the sensitivity and specificity of the functional S-T segment response were apparent. The abnormal S-T segment response to exercise testing did not absolutely predict the future presentation of coronary artery disease, and a normal response to maximal treadmill testing did not rule out this possibility. Because premature ventricular contractions demonstrated a very low sensitivity, predictive value and risk ratio they were not a practical indicator of increased risk for latent coronary artery disease except when associated with an abnormal S-T segment response.