Biomedical subjects

K A Hasselfeld

Publications and source records attributed to K A Hasselfeld.

4 recordsLinked to original sources

PubMed1995

Allastair B. Karmody Award. Calf vein thrombi are not a benign finding.

BACKGROUND: Currently, there is no consensus in the literature regarding which patients with calf vein thrombi are at high risk for proximal propagation. This study examined patients with isolated calf vein thrombi with serial duplex scans in order to identify risk factors that would predict outcome. PATIENTS AND METHODS: Between May 1989 and November 1994, 288 patients were identified with isolated calf vein thrombi. One hundred ninety-two of them had sequential scans performed. RESULTS: Fifty-three (28%) of the 192 patients had propagation of their initial thrombi. The most proximal level of propagation was the popliteal vein in 11 patients, the superficial femoral vein in 5, the common femoral vein in 5, adjacent tibial or soleal veins in 24, adjacent soleal veins alone in 7, and the lesser saphenous vein in 1. Three patients whose thrombi propagated had free-floating thrombus tips in the large veins of their thighs. Symptoms, prophylaxis, and risk factor analysis comparing those patients whose thrombi propagated to those whose thrombi did not found no statistically significant prognostic value. Single or multiple calf vein thrombi did not predict propagation. Of the 23 patients treated with heparin, only 3 had thrombus propagation. None of these reached the level of the knee (including popliteal vein). CONCLUSIONS: The natural history of distal lower extremity thrombosis does not appear to be as benign as previously believed.

Female↗

PubMed1995

Vascular laboratory personnel on-call: effect on patient management.

PURPOSE: A prospective study was undertaken of all vascular laboratory tests performed by the "on-call" technologist during a 3-year time period. METHODS: Technologists take call on a rotating basis. All patients evaluated had symptoms. History and risk factor data were collected at the time of patient encounter. RESULTS: Studies were initiated from the emergency department 56% of the time, from inpatient examinations 33% of the time, and from outpatient examinations 11% of the time. Ninety percent (n = 440) of the studies obtained were venous duplex scans (VDS). Fifty-eight percent (257 of 440) of the studies were performed on weekends. Thirty-two percent of the studies resulted in admission of the patient. Of the 440 VDS obtained, 51% (224 of 440) identified some type of disease. Acute deep venous thrombosis (DVT) was diagnosed in 15% (67 of 440), acute superficial venous thrombosis (SVT) in 4% (17 of 440), acute DVT and SVT in 7% (31 of 440), chronic DVT in 4% (17 of 440), chronic SVT in 4% (16 of 440), and chronic DVT and SVT in 1% (3 of 440); 2% (9 of 440) of the DVTs were of indeterminate age. Other diseases were identified in 22% (95 of 440), including popliteal cysts, inguinal lymphadenopathy, and soft tissue edema. CONCLUSIONS: Having an "on-call" vascular technologist has allowed patients with acute venous thrombosis to be triaged and admitted, if necessary, in a timely fashion. Those patients who have symptoms and a negative VDS result are able to avoid unnecessary hospitalization and treatment. The expense of this service is easily justified by the savings of unnecessary hospital days.

Chi-Square Distribution↗

PubMed1994

Does the asymptomatic limb harbor deep venous thrombosis?

Deep venous thrombosis (DVT) is a great masquerader that cannot be reliably predicted by a patient's symptoms, history, or risk factors. Bilateral lower extremity duplex ultrasonography scans were made of 2,511 patients and analyzed to identify, if possible, a population in which a unilateral study would be appropriate. A total of 1,086 (43%) patients were found to have deep venous thrombosis--742 (30%) unilateral and 344 (14%) bilateral. Of the patients with DVT for whom side-of-symptom information was recorded, 64% had symptoms referable to the involved extremity and 36% had symptoms referable to the contralateral extremity. Of the 362 patients who had asymptomatic lower extremities, 128 (35%) had DVT. Moreover, clots were found in asymptomatic limbs in an additional 263 patients whose contralateral limb was symptomatic. Logistic regression analysis did not reveal combinations of symptoms and risk factors that could predict DVT. If DVT is suspected, the patient should undergo bilateral lower extremity duplex scanning.

Acute Disease↗

PubMed1990

Upper extremity venous thrombosis diagnosed by duplex scanning.

The incidence of axillary-subclavian venous thrombosis continues to rise, while reports of noninvasive methods to diagnose this condition have been sparse. A review of the records of 693 consecutive upper extremity duplex scans was performed, and a diagnosis of acute venous thrombosis was made in 123 of these patients. Of these, 85 involved the axillary or subclavian vein. Use of a central venous catheter was the most common risk factor for axillary-subclavian venous thrombosis. Within this group, 8% had a pulmonary embolism, of which 25% were fatal. Follow-up of patients with axillary-subclavian venous thrombosis at a mean of 2 years revealed that 49% of these patients had died. Of the remaining patients, more than one third had evidence of the post-thrombotic syndrome. Duplex scanning of the venous system provides a safe, reliable, and repeatable method of evaluating and following patients with suspected venous thrombosis of the upper extremity.

Acute Disease↗