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Biomedical subjects

J Brumm

Publications and source records attributed to J Brumm.

6 recordsLinked to original sources
PubMed2002

Exposure misclassification and threshold concentrations in time series analyses of air pollution health effects.

Linear, no-threshold relationships are typically reported for time series studies of air pollution and mortality. Since regulatory standards and economic valuations typically assume some threshold level, we evaluated the fundamental question of the impact of exposure misclassification on the persistence of underlying personal-level thresholds when personal data are aggregated to the population level in the assessment of exposure-response relationships. As an example, we measured personal exposures to two particle metrics, PM2.5 and sulfate (SO4(2-)), for a sample of lung disease patients and compared these with exposures estimated from ambient measurements Previous work has shown that ambient:personal correlations for PM2.5 are much lower than for SO4(2-), suggesting that ambient PM2.5 measurements misclassify exposures to PM2.5. We then developed a method by which the measured:estimated exposure relationships for these patients were used to simulate personal exposures for a larger population and then to estimate individual-level mortality risks under different threshold assumptions. These individual risks were combined to obtain the population risk of death, thereby exhibiting the prominence (and the value) of the threshold in the relationship between risk and estimated exposure. Our results indicated that for poorly classified exposures (PM2.5 in this example) population-level thresholds were apparent at lower ambient concentrations than specified common personal thresholds, while for well-classified exposures (e.g., SO4(2-)), the apparent thresholds were similar to these underlying personal thresholds. These results demonstrate that surrogate metrics that are not highly correlated with personal exposures obscure the presence of thresholds in epidemiological studies of larger populations, while exposure indicators that are highly correlated with personal exposures can accurately reflect underlying personal thresholds.

Air Pollution↗
PubMed1995

Small bowel transplantation.

Small bowel transplantation (SBT) presents a formidable challenge to perioperative nurses. Patients who survive these procedures have difficult postoperative courses with lengthy intensive care stays. They also are at significant risk for graft rejection and long-term immunosuppression complications. The option for SBT is reserved for patients who otherwise face the prospect of life-long total parenteral nutrition (TPN). Advances in donor and recipient surgical techniques and improvements in immunosuppressive therapies have raised hopes that patients with intestinal failures who undergo SBT procedures will be allowed to resume full oral nutrition and independence from TPN.

Animals↗
PubMed1992

Liver transplantation.

Nationwide, healthcare professionals are more involved with liver transplantation. Although providing a new lease on life is very rewarding within itself, it can also be stressful for all involved. Through a better understanding of the actual procedure, healthcare professionals can alleviate some of their own stress as well as understand the anxiety of the recipient.

Academic Medical Centers↗
PubMed1991

A donation to life: organ procurement.

1. Only 15% of brain dead patients become organ donors. This is due to a lack of public education regarding the benefits of organ donation, lack of recognition of potential donors, poor donor management, and unfortunately, even the reluctance of health-care workers to approach families with the choice to donate. 2. Once the patient has been officially accepted as an organ donor and the consents have been signed, the donor goes through a thorough evaluation involving physician consultations and lab work, and the medical history is reviewed for possible complications. 3. As many as four surgical teams may be involved in organ procurement, and good communication between nurses, physicians, and coordinators is vital to promote successful recovery of donor organs.

Brain Death↗
PubMedDate not supplied

Exposure of chronic obstructive pulmonary disease patients to particles: respiratory and cardiovascular health effects.

To examine hypotheses regarding air pollution health effects, we conducted an exploratory study to evaluate relationships between personal and ambient concentrations of particles with measures of cardiopulmonary health in a sample of patients with chronic obstructive pulmonary disease (COPD). Sixteen currently non-smoking COPD patients (mean age=74) residing in Vancouver were equipped with a particle (PM(2.5)) monitor for seven 24-h periods. Subjects underwent ambulatory heart monitoring, had their lung function and blood pressure (BP) measured, and recorded symptoms and medication use. Ambient PM(2.5), PM(10), sulfate, and gaseous pollutant concentrations were monitored at five sites within the study area. Although no associations between air pollution and lung function were statistically significant, an estimated effect of 3% and 1% declines in daily FEV(1) change (DeltaFEV(1)) for each 10 microg/m(3) increase in ambient PM(10) and PM(2.5), respectively, was observed. Increases of 1 microg/m(3) in personal or ambient sulfate were associated with 1.0% and 0.3% declines in DeltaFEV(1), respectively. Weak associations were observed between particle concentrations and increased supraventricular ectopic heartbeats and with decreased systolic BP. No consistent associations were observed between any particle metric and diastolic BP, heart rate, or heart rate variability (r-MSSD or SDNN), symptom severity, or bronchodilator use. Of the pollutants measured, ambient PM(10) was most consistently associated with health parameters; the use of personal exposures did not improve the strength of any associations or lead to increased effect estimates.

Aged↗