Biomedical subjects

B H Nguyen

Publications and source records attributed to B H Nguyen.

8 recordsLinked to original sources

PubMed2004

Epidemiology of electrical and lightning related deaths and injuries among Canadian children and youth.

Among burn injuries, electrical injuries constitute a small but devastating fraction. To describe the epidemiology of electrical injuries in Canadian children, data on deaths and emergency department visits related to electrical injuries, including lightning strikes, were obtained from provincial coroners' offices and the Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP) respectively, for the years 1991-96. Twenty one deaths and 606 emergency visits highlight that electrical related deaths, more frequent among school age children, are more likely the result of high voltage and lightning strike, while emergency department visits, more frequent among younger children, are more likely the result of low voltage. While the introduction of legislated standards for child safe outlets and educational programs for parents, children, and youth are recommended strategies toward reducing the frequency of these incidents, these strategies require further evaluation before their effectiveness can be estimated.

Accidents, Home↗

PubMed2001

Does willingness to pay vary by race/ethnicity? An analysis using mammography among low-income women.

As part of a population-based intervention to improve periodic mammogram screening, we examined WTP for mammography in five ethnic groups. Through random digit dialing, we contacted households in low-income census tracts of Alameda County, California (San Francisco Bay area). Women who met the ethnicity, age and cancer-free eligibility criteria were invited to participate. For the baseline assessment, women were surveyed over the phone in their preferred language. Of the 1465 surveyed women, 499 identified themselves as African-American, 199 were Chinese, 167 were Filipino, 300 were Latina, and 300 were non-Hispanic white. Bivariate and multivariate analysis showed that WTP varied significantly by ethnicity (P<0.05). We also found that when Filipino and Chinese women had a female relative with breast cancer, they were willing to pay less money for a mammogram. African-American, Latino, and non-Hispanic white women, however, were willing to pay more money for a mammogram if a female relative had had breast cancer. This ethnic difference, when there is a familial link to breast cancer, needs further study as it has implication for genetic testing. Nevertheless, WTP studies that do not account for ethnic differences may be overstating net benefits to society.

California↗

PubMed2001

Abnormal Pap smear follow-up in a high-risk population.

Low-income women are at high risk of developing cervical cancer attributable not only to the higher prevalence of risk factors in this population but also to the lack of timely follow-up of abnormal Pap smears. This study evaluates the efficacy of an aggressive follow-up strategy. Women with abnormal Pap smear results after screening in a public hospital emergency department were randomly assigned to follow-up either by a case-managed approach using computerized tracking and universal colposcopy or by traditional care. The main outcome was the proportion of women receiving follow-up in 6 months. A secondary outcome was the proportion of women receiving follow-up by 6 months and diagnostic resolution in 18 months. Of 54 women in the intervention group, 65% kept at least one follow-up appointment in 6 months compared with 41% of the 54 women in the control group (P = 0.012). Half the women in the intervention group versus 19% of women in the control group had follow-up in 6 months and diagnostic resolution in 18 months (P = 0.001). After adjusting for age, initial Pap smear result, and race/ethnicity, the odds of having follow-up in 6 months were four times greater for women in the intervention group (odds ratio = 4.0; 95% confidence interval, 1.6-9.7), and the odds of having both follow-up in 6 months and diagnostic resolution in 18 months were more than six times greater (odds ratio = 6.5; 95% confidence interval, 2.4-17.8). This study demonstrates that an aggressive follow-up strategy significantly improves the rate of both initial follow-up and diagnostic resolution of abnormal Pap smears among low-income women with atypical squamous cells of undetermined significance and atypical glandular cells of undetermined significance when compared with traditional care.

Adolescent↗

PubMed2000

Promoting cancer prevention activities among Vietnamese physicians in California.

BACKGROUND: To promote prevention and early detection of cancer, the authors conducted a three-year intervention targeting Vietnamese physicians in solo practice in California. METHODS: Twenty subjects who had received their medical training in Vietnam were recruited into a randomized controlled trial. The intervention included computerized or manual cancer screening reminders, continuing medical education seminars, Vietnamese-language health education materials, newsletters, and oncology data-query programs. Evaluation included chart audits for eight targeted activities pre- and post-intervention. RESULTS: Before the intervention, annual physician performance rates were low for all eight activities: routine checkups (65.6%), Pap testing (13.8%), pelvic examinations (19.8%), clinical breast examinations (13.3%), mammography (6.4%), hepatitis B serologies (21.9%), hepatitis B immunizations (12.8%), and smoking cessation counseling (1.6%). After the intervention, performance rates increased significantly for smoking cessation counseling (p = 0.02), Pap testing (p = 0.004), and pelvic examinations (p = 0.01). CONCLUSIONS: The results demonstrate the efficacy of an intervention targeting Vietnamese primary care physicians in promoting smoking cessation counseling, Pap testing, and pelvic examinations, but not other cancer prevention activities.

Adult↗

PubMed1999

Effect of a media-led education campaign on breast and cervical cancer screening among Vietnamese-American women.

BACKGROUND: Previous research has shown that breast and cervical cancer screening rates are low among Vietnamese women. METHODS: Over a 24-month period, we implemented a media-led community education campaign to promote recognition, intention, receipt, and currency of routine checkups, clinical breast examinations, mammograms, and Pap tests among Vietnamese-American women in Alameda and Santa Clara Counties in northern California. Women in Los Angeles and Orange Counties in southern California served as controls. To evaluate its impact, pretest telephone interviews were conducted of 451 randomly selected women in the intervention area and 482 women in the control area and posttest interviews with 454 and 422 women, respectively. RESULTS: At posttest, after controlling for demographic differences in the surveyed populations, the odds ratios for the intervention effect were statistically significant for having heard of a general checkup, Paptest, and clinical breast examination (CBE); planning to have a checkup, Pap test, CBE, and mammogram; and having had a checkup and Pap test. The intervention had no effect on being up to date for any of the tests. CONCLUSIONS: A media-led education intervention succeeded in increasing recognition of and intention to undertake screening tests more than receipt of or currency with the tests.

Adult↗

PubMed1999

Physiologic identification of eighth nerve subdivisions: direct recordings with bipolar and monopolar electrodes.

The purpose of this study was to determine stimulation and recording parameters that maximize differences in evoked responses recorded between the cochlear nerve and the surrounding tissues. Click-evoked potentials were obtained using monopolar and bipolar recording electrodes placed directly on the exposed eighth nerve of anesthetized cats. Responses were compared as stimulus intensity, electrode location, and bipolar electrode orientation and interelectrode spacing were systematically varied. Wave amplitudes increased monotonically with intensity for both monopolar and bipolar configurations, but bipolar configurations exhibited greater selectivity in differentiating cochlear from vestibular subdivisions. The optimal stimulus intensity was 70 to 80 dB peak sound pressure level (pSPL). Monopolar recordings were often confounded by activity originating at remote sites, typically the cochlear nucleus and (for recording sites on the vestibular nerve) the cochlear nerve. Bipolar response amplitudes increased with interelectrode spacing and were largest when electrodes were oriented parallel to the long axis of the nerve. Extrapolation of empirical data indicated that amplitudes of bipolar responses would be maximal at an electrode separation of 7.5 mm. Cochlear nerve conduction velocity, calculated from wave latencies at each of the two monopolar electrodes, was 11.6 +/- 1.6 m/sec.

Animals↗

PubMed1999

CathSim: an intravascular catheterization simulator on a PC.

The development of a medical simulator that incorporates substantial training value and realism into an affordable product has been a huge challenge for the simulation community. A large hurdle to making an inexpensive simulator has been the high cost of the computers needed for adequate realism. We have met this challenge by developing CathSim, a low-cost medical simulator that integrates force feedback, multimedia, and 3D graphics simulation technology on an industry standard PC. This product is commercially available and is currently being used by numerous training institutions and hospitals. The CathSim system includes software and a force feedback interface device. The platform and device can be used to train health care providers to perform needle-stick medical procedures. Our first module teaches users the techniques of peripheral intravenous (i.v.) catheterization. Other training modules that will be added to the CathSim platform include central venous catheter (CVC) insertion and peripherally inserted central catheter (PICC) placement. This paper discusses the challenges of this project and the trade-offs and solutions that we developed to overcome them. We describe our process of analyzing and prioritizing the medical tasks necessary to correctly perform peripheral intravenous catheterization. This analysis and prioritization was used to decide which tasks would be included in the simulator and how the included tasks would be replicated. We discuss the method by which we obtained the needed realism in the 3D graphics rendering and in the tactile feedback of the input device. We illustrate how we blended together simulation and multimedia technology to ensure adequate immersion and training efficacy, while keeping the system cost to a minimum.

Computer Simulation↗

PubMed1996

The teleos virtual environment toolkit for simulation-based surgical education.

In the past, surgical simulations have largely been created through the development of dedicated applications that require considerable programming and computer graphics skills. Advances in simulation-based surgical education have been limited by this dependence on computer graphics programming expertise. To lower barriers to the adoption of simulation-based training, we are developing tools based on Teleos, software technology that allows a wide variety of medical content developers to author surgical training simulations without programming.

Computer Graphics↗