Medical instrumentation
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Medical instrumentation · Jun 1987
Comparative StudySimultaneous comparison of three noninvasive oximeters in healthy volunteers.
Noninvasive monitoring of arterial hemoglobin oxygen saturation (SaO2) from the Nellcor N-100 and the Ohmeda-Biox 3700 pulse oximeters were compared with SaO2 measured simultaneously by the Hewlett-Packard 47201A ear oximeter. A total of 868 pairs of data points ranging in saturation from 55-100% were obtained from 31 healthy adult volunteers of different ages, sex, skin pigmentation, height, weight, hematocrit, and smoking habits. ⋯ The equations for the best fitted linear regression line between the Nellcor and the Ohmeda-Biox pulse oximeters as compared to the reference Hewlett-Packard ear oximeter readings were Y = 0.92X + 7.45 and Y = 1.10X - 10.73, respectively. Our study showed that despite a very close correlation among these three oximeters (r = 0.98), when compared to the Hewlett-Packard ear oximeter, the Nellcor pulse oximeter overestimates SaO2 by 2-4%, whereas the Ohmeda-Biox pulse oximeter underestimates SaO2 by 3-6% for SaO2 levels between 70 and 55%.
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Electrosurgical burns are said to be the most common electrical hazards in operating rooms. Characteristic of all burns is that the user is not sufficiently familiar with electrosurgery, its power, and possible dangers. ⋯ From the physics of electrosurgery and heat production, it can be shown that a residual voltage across the neutral electrode plays a dominant role. To monitor this voltage and process it in an appropriate way will open new possibilities in avoiding burns.
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Medical instrumentation · Jul 1985
Display adaptor for the Vitatek #511 monitor and the Puritan-Bennett CO2 analyzer.
Many CO2 infrared analyzers require additional graphics devices for continuous CO2 waveform display. An adaptor was designed to integrate the output of a Puritan-Bennett infrared CO2 analyzer into the display of a Vitatek #511 patient monitor. The adaptor is made with inexpensive off-the-shelf components and proved successful during more than six months of use.