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I Hinberg

Publications and source records attributed to I Hinberg.

41 records · Page 3Linked to original sources
PubMedDate not supplied

Walkie-talkies and cellular telephones: the hazards of electromagnetic interference in hospitals.

This article presents an overview of the effects of electromagnetic interference (EMI) on medical devices, with emphasis on portable telecommunication devices. In addition, the authors discuss existing voluntary national and international standards and policies governing the use of cellular telephones and walkie-talkies in hospitals, possible solutions to the susceptibility of medical devices to EMI, and recommendations to lessen EMI's potentially hazardous effects.

Canada↗
PubMedDate not supplied

Effects of a wireless local area network (LAN) system, a telemetry system, and electrosurgical devices on medical devices in a hospital environment.

Concerns have been raised about interference of wireless local area network (LAN) systems and telemetry systems with medical devices in hospitals. The authors have investigated the susceptibility of 65 electromedical devices to a wireless LAN system and a telemetry system in preselected areas of a hospital. Testing was based on the American National Standards Institute Standard C63.18. The wireless LAN system operated at 2.42 GHz with an output power of 100 mW. The telemetry system operated at 466 MHz with an output power of 4 mW. Of the 65 devices tested, only two hand-held Doppler units, a Mini Doppler Model D900 (Huntleigh Healthcare Ltd) and a Ultrasonic Doppler Model 811 (Parks Medical Electronics, Inc.), were affected by the LAN system. Placed within 10 cm of the LAN system in standby mode, both units emitted periodic high-pitched beating sounds, which could be misinterpreted as normal beating sounds from the patient. These changed to random static noise during data transmission by the LAN. Under normal conditions of use, a LAN system would never be placed this close to a medical device. The quality of data transmission from the LAN system changed from "good" to "acceptable" in the colonoscopy room. This deterioration in transmission quality could have been caused by the lead shielding in the room. Electrosurgical devices operating at 0.5 to 1 MHz did not affect the LAN system at distances up to 3 m. None of the devices was affected by the telemetry system. These findings suggest that wireless LAN systems and telemetry systems can be acceptable for use in hospitals. Nevertheless, other systems should be tested on potentially susceptible devices by the hospital before use.

Artifacts↗
PubMedDate not supplied

Formation of precipitate in priming solutions for extracorporeal perfusion.

A precipitate observed in Hartman's solution used to prime a cardiopulmonary bypass circuit was identified as calcium carbonate. Analysis of the chemical equilibrium showed that the precipitation was caused by sodium bicarbonate added to prevent acidosis. Although this practice is acceptable for haemic primes, in which buffers and albumins will prevent precipitation, it should not be done with non-haemic primes prior to bypass.

Bicarbonates↗
PubMedDate not supplied

Temperature distribution beneath pediatric electrosurgical dispersive electrodes: a model study.

Concerns have been raised about the safety and the thermal performances of commercially available electrosurgical dispersive electrodes. A model system was designed to simulate the thermal effects observed in humans. The following critical factors affecting the thermal performances of pediatric electrodes were investigated: the intensity and duration of the applied current, the electrical resistivity of the test medium, the contact interface area between the electrode and the test medium, and the water content of the adhesive gel of the electrode. The maximum temperature rises (delta Tm) under the electrodes were 0.6 +/- 0.1 degrees C, 2.8 +/- 0.2 degrees C, and 5.2 +/- 0.3 degrees C when 60 s of 1 A, 2 A, and 3 A currents, respectively, were applied. delta Tm increased linearly with the increase of the duration of applied current and the resistivities of the test medium. When dispersive electrodes with reduced areas or reduction of water content of the adhesive gel of the electrodes were used, delta Tm increased with the areas or the water contents decreased. The currents and durations used in this study were in excess of those routinely used in electrosurgery. The study confirmed that the maximum temperature increase under the electrode is inversely proportional to the square of the perimeter of the electrode, rather than the square of the surface area. The test methods described can be used to evaluate the thermal performances of other electrosurgical dispersive electrodes. Monitoring the impedance at the interface between the dispersive electrode and the tissue in contact would reduce the risk of burns.

Child↗