We obtained echocardiographic measurements of interventricular septal and posterior left ventricular wall thickness in 100 apparently normal subjects in whom there was no evidence or history of coronary artery disease, hypertension or prolapsing mitral valve. Subjects were divided into five age groups of 20-29, 30-39, 40-49, 50-59 and 60-70 years and there were 20 subjects in each group. Measurements of interventricular septum and posterior left ventricular wall thickness were made in each subject at both mitral and sub-mitral levels at the time of Q wave inscription, and the measurements were related to body surface area. The interventricular septum increased from a median of 8.3 mm in the age group 20-29 to 11.2 mm in the group 60-70, whereas the posterior left ventricular wall increased from 7.5 mm to 9.8 mm. The difference in the medians between the groups 20-29 and 60-70 was statistically significant for both interventricular septum and posterior left ventricular wall (P less than 0.02). Our data showed that interventricular septal, posterior left ventricular wall thickness measurements and their ratio should be related to age in order to assess their significance.

Adult↗

PubMedDate not supplied

Sources of disagreement among public and private agency paramedics.

INTRODUCTION: The purpose of the study was to document the occurrence and causes of disagreements between paramedics in a tiered-response emergency medical services (EMS) system. METHODS. This cohort analysis of disagreements between paramedics sampled 63 male public agency, 90 male private agency, and 41 female private agency paramedics. Paramedics responded to Likert-type items and one open-ended item concerning the occurrence of conflict between paramedics. RESULTS: On-scene conflict between EMS personnel from public and private agencies was reported by 70% of the respondents. Conflicts that interfered with patient care were reported to occur more frequently between paramedics from different types of agencies. The most commonly mentioned subject of disagreement was patient treatment, followed by patient transport, interpersonal and interagency conflicts, and patient assessment. CONCLUSION: A majority of paramedics have experienced on-scene disagreements with other paramedics. Disagreements occur more frequently between paramedics from different agencies and encompass a wide range of issues concerning patient care and interpersonal relationships.

Adult↗

PubMedDate not supplied

Influence of demographic variables in prehospital treatment of patients with chest pain.

OBJECTIVE: To determine whether the number of interventions requested by EMS personnel for patients with acute, nontraumatic chest pain varied with the patient's gender or race. METHODS: The authors conducted a retrospective chart review of the care requested for patients 17 years old or older complaining of acute, nontraumatic chest pain by one EMS squad in a city of 50,000 people over a six-month period. Interventions recorded for each patient included oxygen administration, artificial airway placement, intravenous fluid administration, defibrillation, and use of lidocaine and nitroglycerin. RESULTS: Of the 169 patients in this study, 54% (n = 92) were white and 56% (n = 95) were female. Age was missing for two patients; of the remainder, 75% (n = 127) were 40 years old or older. The numbers of interventions requested ranged from 0 to 4. EMS personnel requested supplemental oxygen for 163 patients. 81% of the females had i.v. lines placed or attempted, compared with 70% of the males; EMS personnel requested orders for nitroglycerin for 43% of the females and 29% of the males. Whites were more likely than nonwhites to have requests for i.v. lines or nitroglycerin. Overall, the numbers of interventions were similar among young females and among older patients, regardless of race or gender. The pattern for young males was different, with significantly more requests for interventions for young white males than for young non-white males (1.89 vs 1.34). CONCLUSIONS: Among older patients and among young females, EMS personnel requested similar numbers of interventions for patient complaining of acute, nontraumatic chest pain regardless of patients race. Patterns of care appeared to differ for young males, a finding that warrants further study.

Acute Disease↗

PubMedDate not supplied

A return-to-school program for the burned child.

Explore the source record for details and available documents.

Adolescent↗

PubMedDate not supplied

Monte Carlo dosimetry for 125I and 60Co in eye plaque therapy.

Monte Carlo calculations of radiation dosimetry using MORSE code are performed for 125I and 60Co point sources in a cylindrical head phantom that simulates the geometry of eye plaque therapy for choroidal melanoma. We obtain the dose variation in the eye at submillimeter intervals over distances as close as 1 mm and up to 2.5 cm from the source. The calculations for 125I are performed for the phantom media of water, protein, and a homogenized protein-water mixture simulating the composition of the eye. Relative dose functions for 125I for these phantom media are fitted to second-degree polynomials. Agreement is found with published results. The relative dose function for 60Co at eye position in the water head phantom is fitted to a third-degree polynomial and compared with that for 60Co at the center of a large water sphere. A boundary effect due to the head phantom-air interface on the dose distribution for 60Co is demonstrated. The dose falloff with distance is faster for the eye geometry compared with the bulk geometry. We also show that the relative dose distributions within the tumor are comparable for 125I and 60Co by comparing their relative dose functions. This result is consistent with the success of clinical trials of large melanoma treatments with 125I plaques.

Biophysical Phenomena↗

PubMedDate not supplied

Dose rate determination for 125I seeds.

Dose rates in water have been determined for the two types of 125I seed currently used in brachytherapy. The need for such determinations became evident when water/air ratios measured with a silicon diode were found to be lower than expected. Extensive measurements using lithium fluoride thermoluminescent dosimeters (TLD's) have been performed in a solid water phantom, at distances from 0.1 to 10 cm from the seed center and at angular increments of 10 degrees, 15 degrees, or 30 degrees within a plane through the seed axis. Dose calibration of the TLD's was accomplished by irradiation in air with 125I seeds of the same type and of strengths traceable to a calibration at the National Institute of Standards and Technology (NIST). Relative calibration of TLD's was monitored by irradiation, in an oven-type x-ray machine, of control dosimeters simultaneously and all dosimeters intercurrently with the 125I irradiations. Values obtained for the dose rate constant, i.e., dose rate per unit air-kerma strength at 1 cm on the transverse axis, were 0.853 and 0.932 cGy h-1 U-1 (1.08 and 1.18 cGy h-1 mCi-1) for the 6711 and 6702 seeds, respectively. Measured data were supplemented with Monte Carlo-calculated relative dose rate data generated using the MORSE code. These calculations used 100 energy groups from 10 to 35.4 keV and involved energy collection bins ranging from 0.025 to 1.2 cm on an edge. Normalized at 1 cm, transverse axis calculated data are not significantly different from measured data (ours or cited literature) at distances either less than 2.5 or greater than 8 cm. Normalized at different distances along the transverse axis, our off-axis calculated and measured distributions agree closely at all angles but differ from literature measured distributions at small (less than or equal to 1 cm) distances and, for small angles, increasingly at larger distances (greater than or equal to 5 cm).

Brachytherapy↗

PubMedDate not supplied

Dosimetry for 125I seed (model 6711) in eye plaques.

The effect of eye plaque materials (gold backing and silastic seed-carrier insert) on the dose distribution around a single 125I seed has been measured, using cubic lithium fluoride thermoluminescent dosimeters (TLDs) 1 mm on an edge, in a solid water eye phantom embedded in a solid water head phantom. With an 125I seed (model 6711) positioned in the center slot of the silastic insert for a 20-mm plaque of the design used in the collaborative ocular melanoma study (COMS), dose was measured at 2-mm intervals along the plaque central axis (the seed's transverse axis) and at various off-axis points, both with and without the COMS gold backing placed over the insert. Monte Carlo calculations (MORSE code) were performed, as well, for these configurations and closely the same geometry but assuming a large natural water phantom. Additional Monte Carlo calculations treated the case, both for 20- and 12-mm gold plaques, where the silastic insert is replaced by natural water. Relative to previous measurements taken in homogeneous medium of the same material (without the eye plaque), the dose reduction found by both Monte Carlo and TLD methods was greater at points farther from the seed along the central axis and, for a given central-axis depth, at larger off-axis distances. Removal of the gold backing from the plaque did not make measurable difference in the dose reduction results (10% at 1 cm).

Brachytherapy↗

PubMedDate not supplied

Probucol treatment affects the cellular composition but not anti-oxidized low density lipoprotein immunoreactivity of plaques from Watanabe heritable hyperlipidemic rabbits.

Use of the antioxidant probucol has been associated with a reduction in the development of atherosclerotic lesions in Watanabe heritable hyperlipidemic (WHHL) rabbits, an animal model of familial hypercholesterolemia. In this study, atheromatous lesions from control or probucol-treated WHHL rabbits were probed with monoclonal antibodies to evaluate whether use of this drug either affected the presence or distribution of epitopes recognized by an antibody against oxidized low density lipoprotein or altered the cellular makeup of lesions. Although probucol-treated animals had much less aortic atherosclerosis than did controls, equivalent immunoreactivity for the anti-oxidized LDL antibody (OXL 41.1) was demonstrated in atherosclerotic lesions of both groups of animals, consistent with a role for oxidative modification of lipoproteins in atherogenesis in this animal model. Use of smooth muscle cell-specific (HHF-35) and macrophage-specific (RAM-11) antibodies demonstrated that lesions from probucol-treated animals were significantly smaller (p less than 0.01) and less cellular (p less than 0.05) than were control lesions. In addition, smooth muscle cells were the predominant cell type in lesions from probucol-treated animals, whereas macrophages predominated in lesions from controls (p less than 0.01). These findings are consistent with a reduction of monocyte/macrophage recruitment into or retention in lesions in probucol-treated animals, or with probucol-induced alterations in the production of growth factors or cytokines that might influence the cellular makeup of atherosclerotic lesions.

Animals↗