The Relative Value of Various Types of High-Tension Transformers (Including Coil) Used for the Production of X-Rays

The —SH compound cysteamine and its —SS product, cystamine, have been tested as protective agents against x-irradiation death for adult CF1 mice of both sexes, and also the 15.5–17.5-day fetuses of the same strain. Control fetuses of 15.5–17.5 days rarely survived x-irradiation to 600 r or more while those whose mothers were injected with cysteamine prior to irradiation could tolerate 700-r x-rays and the majority of offspring survived 30 days postparturition. When irradiated fetuses were given foster (normal) mothers at birth, survival was further improved, but only in those whose mothers were given the drug just prior to irradiation. Cystamine also gave protection to the fetuses. Optimum survival of controls exposed at 17.5 days to 700-r x-rays was 19% at 30 days, while those ‘protected’ by cysteamine showed 50% survival and with cystamine, 41% survival. Thus there was definitely fetal ‘protection’ by either drug. Adult males and females of the same strain showed considerable ‘protection’ by either drug, the males increasing survival from 2% to 30% (cystamine) and 34% (cysteamine) while the females showed increased survival value to 56% and 64%, respectively. It is apparent that both of these drugs have protective value for fetal and adult mice of both sexes, when they are exposed to the ld50/30-day level of x-rays.

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Estimation of the Overuse of Preoperative Chest X-rays According to “Choosing Wisely”, “No Hacer”, and “Essencial” Initiatives: Are They Equally Applicable and Comparable?

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17238783 ◽

2020 ◽

Vol 17 (23) ◽

pp. 8783

Author(s):

Jorge Vicente-Guijarro ◽

José Valencia-Martín ◽

Paloma Moreno-Nunez ◽

Pedro Ruiz-López ◽

José Mira-Solves ◽

...

Keyword(s):

Tertiary Hospital ◽

Choosing Wisely ◽

X Rays ◽

X Ray ◽

Relative Value ◽

Wide Variability ◽

Chest X Ray ◽

American Society ◽

Practice Methods ◽

Preoperative Chest

Background: Overuse reduces the efficiency of healthcare systems and compromises patient safety. Different institutions have issued recommendations on the indication of preoperative chest X-rays, but the degree of compliance with these recommendations is unknown. This study investigates the frequency and characteristics of the inappropriateness of this practice. Methods: This is a descriptive observational study with analytical components, performed in a tertiary hospital in the Community of Madrid (Spain) between July 2018 and June 2019. The inappropriateness of preoperative chest X-ray tests was analyzed according to “Choosing Wisely”, “No Hacer” and “Essencial” initiatives and the cost associated with this practice was estimated in Relative Value and Monetary Units. Results: A total of 3449 preoperative chest X-ray tests were performed during the period of study. In total, 5.4% of them were unjustified according to the “No Hacer” recommendation and 73.3% according to “Choosing Wisely” and “Essencial” criteria, which would be equivalent to 5.6% and 11.8% of the interventions in which this test was unnecessary, respectively. One or more preoperative chest X-ray(s) were indicated in more than 20% of the interventions in which another chest X-ray had already been performed in the previous 3 months. A higher inappropriateness score was also recorded for interventions with an American Society of Anesthesiologists (ASA) grade ≥ III (16.5%). The Anesthesiology service obtained a lower inappropriateness score than other Petitioning Surgical Services (57.5% according to “Choosing Wisely” and “Essencial”; 4.1% according to “No Hacer”). Inappropriate indication of chest X-rays represents an annual cost of EUR 52,122.69 (170.1 Relative Value Units) according to “No Hacer” and EUR 3895.29 (2276.1 Relative Value Units) according to “Choosing Wisely” or “Essencial” criteria. Conclusions: There was wide variability between the recommendations that directly affected the degree of inappropriateness found, with the main reasons for inappropriateness being duplication of preoperative chest X-rays and the lack of consideration of the particularities of thoracic interventions. This inappropriateness implies a significant expense according to the applicable recommendations and therefore a high opportunity cost.

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An oscillographic study of the production of X-rays by a Coolidge tube

Mathematical Proceedings of the Cambridge Philosophical Society ◽

10.1017/s0305004100000165 ◽

1924 ◽

Vol 22 (1) ◽

pp. 70-75 ◽

Cited By ~ 1

Author(s):

J. A. Crowther

Keyword(s):

Measuring Instruments ◽

X Rays ◽

X Ray ◽

Spark Gap ◽

High Tension

Radiologists have often had cause to note certain apparent anomalies in the behaviour of their apparatus. It is quite well known that different X-ray tubes, excited by different kinds of high tension apparatus, yield X-radiation of markedly varying quality and quantity even under conditions which, as measured by spark gap and milliammeter (the usual measuring instruments of the radiologist), are apparently identical. These anomalies seemed to offer an interesting field for investigation, and one which might not be without value on the practical side.

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