Biomedical subjects

S Miodownik

Publications and source records attributed to S Miodownik.

23 records · Page 2Linked to original sources

PubMed1981

Technical aspects and clinical implications of high frequency jet ventilation with a solenoid valve.

High frequency jet ventilation (HFJV) is an incompletely studied technique of mechanical respiratory support. The authors have built a ventilator based on a solenoid valve, that allows independent selection of respiratory rate and inspiratory/expiratory ratio. The ventilator can be synchronized to the heart rate. Humidification is provided by warm saline dripped in front of the injector nozzle, so that the jet stream itself acts as a nebulizer. Tube diameter, length, and deformability are fundamental determinants of inspiratory flow rate and wave form. Cannula kinking and inadequate humidification were the most significant sources of complications.

Respiration, Artificial↗

PubMed1978

Criteria for selective positive end-expiratory pressure and independent synchronized ventilation of each lung.

Respiratory failure of different origins often requires therapy with mechanical ventilation and positive end-expiratory pressure (PEEP). These supports are occasionally inadequate if the damage to one lung is significantly more pronounced than that to the other lung. Technical means exist to ventilate each lung independently or to provide a different PEEP to each lung. The findings from nine patients in whom one of these techniques was applied are presented, and advantages and disadvantages are discussed.

Adult↗

PubMedDate not supplied

Doubly tuned solenoidal resonators for small animal imaging and spectroscopy at 1.5 Tesla.

The design and construction of solenoidal resonators for use with small animals in a 1.5-Tesla clinical imaging system are described. The coils have been designed to exploit the B1 distributions of two resonant modes of a four-turn solenoid whose windings are in parallel. Both singly and doubly tuned versions have been constructed. 1H images of normal and pathologic anatomy in mice and rats as well as a 31P spectrum of a Walker 256 rat sarcoma are presented. A primary advantage of this design is that the coils are easy to build and implement while providing the necessary sensitivity to allow high quality images to be obtained with no changes to the hardware or software of the clinical unit.

Animals↗

PubMedDate not supplied

Electrosurgical output measurement: a review of methods and a new approach.

Since the introduction of the Electrosurgical Unit (ESU) as an effective tool in the OR and clinic, there has been a need to measure accurately the output of these devices in order to verify their safety, calibration, and performance. This article presents review of ESU measurement techniques, along with an analysis of their advantages and shortcomings. An alternative method is advanced that improves accuracy and resolution, provides extremely flexible selection of load resistance values and current measurement paths, and directly measures Crest Factor, a significant electrosurgical parameter.

Electric Conductivity↗

PubMedDate not supplied

Design of apparatus for precise x-ray dose chamber calibrations.

An apparatus for precision calibration of ion chambers in the x-ray region from 16 to 320 kV is described. The development of a fast-acting shutter with "opening" and "closing" times of less than 3-ms eliminates the requirement for operating time corrections. Controls from outside the radiation room permit changing x-ray filters and alternately positioning both test and standard ion chambers in the x-ray beam. Thus, the remote controls eliminate the need to enter the x-ray room in the course of a series of calibrations. The potential advantages resulting from the capabilities of this apparatus are described in this Technical Report.

Calibration↗