Biomedical subjects
Publications and source records attributed to Bruce H Brundage.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
STUDY OBJECTIVES: To determine the incidence of catheter-related infection in patients with pulmonary arterial hypertension (PAH) receiving epoprostenol (EPO), and to note an etiologic role for Micrococcus spp, which is rarely reported as a pathogen in the medical literature. DESIGN: Observational study. SETTING: Two PAH specialty treatment centers, Harbor-UCLA Medical Center (Torrance, CA), and the College of Physicians and Surgeons, Columbia University (New York, NY). PATIENTS: A total of 192 patients with PAH receiving continuous therapy with IV EPO. INTERVENTIONS: From 1987 to 2000, 192 patients with PAH received infusions of EPO via central venous catheter. Catheter care included regular dressing changes with dry gauze using a sterile procedure, without the use of flushes. Patients were asked to report on known infections and treatments, and symptoms. All infections were verified by a telephone call to the patient, care provider, and microbiology laboratory whenever possible. MEASUREMENTS AND RESULTS: There were 335,285 catheter days (mean +/- SD, 1,325 +/- 974 catheter days). There were 88 clinical catheter infections with 51 blood culture-positive infections, necessitating catheter removal in 38 instances. The following pathogens were isolated: Staphylococcus aureus (25); Micrococcus spp (14); mixed flora (3); coagulase-negative Staphylococcus spp (2); Corynebacterium spp (2); Serratia marcessens (1); Enterobacter spp (1); Pseudomonas aeruginosa (1); enterococci (1); and unidentified Gram-positive cocci (1). The catheter infection rate was 0.26 per 1,000 catheter days. CONCLUSIONS: The use of long-term therapy with continuous EPO appears to be associated with a low incidence of catheter-related infections. Micrococcus spp were the second most common etiologic agent. Caregivers managing patients with PAH must be aware of the risk of catheter infection, as it may contribute to the morbidity and mortality associated with the use of EPO. When isolated, Micrococcus spp should not be viewed as a contaminant, but rather as a true pathogen that may require therapeutic intervention.
OBJECTIVE: To observe the effects of treatment with long-term continuous epoprostenol (Epo) infusion on the survival and pulmonary artery pressure in patients with primary pulmonary hypertension (PPH). METHODS: Sixty nine patients with PPH and congestive heart failure of stage III or IV (classification by New York Heart Association) treated with Epo of initial dose of 2 - 62 ng x kg(-1) x min(-1) (the dosage was enhanced by 1 - 2 ng x kg(-1) x min(-1) every 2 months according to patient's response). All patients underwent right heart catheterization and Doppler echocardiography to measure the systolic pressure gradient between the right ventricle and right atrium (DeltaP) and the cardiac output (CO). Doppler echocardiography and catheterization data were compared. Patients were followed up with echocardiography once every 4 months. RESULTS: Of 69 patients treated with Epo 17 were followed up for > 330 days. During this period, DeltaP decreased from (84.1 +/- 24.1) mm Hg to (62.7 +/- 18.2) mm Hg (P < 0.01), CO increased from (4.00 +/- 1.22) L/min to (4.70 +/- 1.27) L/min (P < 0.02), DeltaP/CO decreased from 22.8 +/- 9.4 to 14.9 +/- 6.5 (P < 0.01). The patient survival was improved. CONCLUSIONS: Patients with PPH treated with continuous infusion of Epo experienced a decrease in pulmonary artery pressure and an increase in cardiac output. Long-term follow-up of some patients of the group demonstrated improved survival during the period of Epo therapy.
OBJECTIVES: The study was done to evaluate whether ethnic differences exist in the prevalence of coronary artery calcification (CAC), and to determine whether differences in calcification correlate with the degree of coronary obstruction. BACKGROUND: Electron beam tomography (EBT) can be used to quantitate the amount of CAC and assist in prognostication of future cardiac events. It is unclear whether ethnic differences in coronary mortality are related to differences in the prevalence of coronary obstruction and CAC. METHODS: A total of 782 symptomatic subjects underwent both EBT and angiography. A 50% luminal narrowing defined an angiographic obstruction. RESULTS: We observed substantial ethnic differences in prevalence of both CAC and angiographic stenosis. In whites (n = 453), prevalence of CAC (score >0) was 84%, and significant obstruction on angiogram was 71%. Compared with whites, blacks (n = 108) had a significantly lower prevalence of CAC (62%, p < 0.001) and angiographic disease (49%, p < 0.01). Hispanics (n = 177) also had a lower prevalence of CAC (71%, p < 0.001) and angiographic obstruction (58%, p < 0.01). Asians (n = 44) were not significantly different in regard to CAC (73%, p = 0.06) or angiographic stenosis (64%, p = 0.30). These ethnic differences remained after simultaneously controlling (by use of multiple logistic regression) for age, gender and cardiac risk factors. CONCLUSIONS: As compared with whites, blacks and Hispanics had significantly lower prevalence of CAC and obstructive coronary disease. Ethnic differences in risk-factor profiles do not explain these differences. This study demonstrated that whites have a higher atherosclerotic burden than blacks and Hispanics, independent of risk-factor differences among symptomatic patients referred for angiography.
BACKGROUND: The sensitivity of coronary calcification by electron beam tomography (EBT) for the detection of coronary atherosclerosis is well-established. Combining the anatomic information of EBT with the functional information of stress testing might reduce the high false-positive result rate seen with treadmill stress test (TMST) alone. No studies have reported the additive value of a negative EBT result (no coronary calcium) for excluding obstructive coronary artery disease (OCAD) in patients with a positive TMST result. This study evaluated the negative predictive value and potential clinical utility of EBT to identify patients with a falsely abnormal TMST. METHODS: A coronary calcium score was determined by EBT for 153 symptomatic patients who underwent coronary angiography because of a positive TMST. The sensitivity, specificity, and predictive values of EBT were determined. A multiple logistic regression analysis compared conventional cardiac risk factors with coronary calcification by EBT for predicting OCAD. A receiver operating characteristic curve was generated plotting sensitivity versus false-positive rate. RESULTS: The false-positive rate of the TMST compared with angiography was 27% (41 of 153). The sensitivity of a nonzero coronary calcium score for OCAD was 98% (110 of 112), with a negative predictive value of 93%. According to multiple logistic regression, coronary calcification by EBT was a stronger predictor of OCAD than any conventional cardiac risk factor. EBT calcium added incremental value to the results of the TMST. Receiver operating characteristic curve analysis found an area under the curve of 0.91 (P <.001). CONCLUSIONS: The absence of coronary calcification by EBT reliably identified patients with a false-positive TMST result. The combination of EBT with TMST is a potentially useful diagnostic strategy to reduce the number of false-positive test results.