The respiratory muscles can present fatigue and even chronic inability to generate force. So, reliable devices are necessary to their evaluation. The aim of this study is to evaluate the MEP (Maximal Expiratory Pressure) values of individuals between 20 and 25 years old and to validate a protocol using a pressure transducer and a signal conditioner comparing it with the digital manometer. We ev...

Serial electrocardiographic (E.C.G.) recordings were taken in seven patients suffering from intracranial conditions, for which their intracranial pressure was directly and continuously monitored with a Konigsberg extradural transducer. The E.C.G. changes observed in patients with raised intracranial pressure were prominent U waves, ST-T segment changes, notched T waves, and shortening and prolo...

A simple instrument for measuring adductor pollicis tension in children has been devised. The thumb sensor utilizes a thin conical rubber seal obtained from a 5, 10 or 20 ml Becton Dickinson syringe. A syringe barrel of similar size, fixed at right angles to the sensor, forms a handle for the fist. The sensor is linked to a pressure transducer with non-compliant tubing. Pressure output of the s...

To assess the performance of transducers used clinically to measure pressure at the skin-cushion interface of seated patients, transducers were placed between slabs of gel and/or foam materials compressed between platens. The recorded pressures consistently exceeded the nominal pressures calculated using the surface area of the slabs. This overestimation, observed in both miniature diaphragm tr...

A new optical pressure transducer system (Viggo) has been assessed and compared with a standard P10 transducer (Spectramed) using a similar 20-gauge cannula, both in vitro in terms of linearity and frequency response and in vivo using an animal model. The linearity of the transducers was comparable; the resonant frequencies were 106 Hz and 75 Hz, respectively. However, the resonant frequency of...

OBJECTIVE To determine whether there was a correlation between tonometric measurements of the intraocular pressure and transducer measurements of the intracranial pressure in the acute setting, and whether intraocular pressure can be used as a surrogate measure of intracranial pressure. Children with traumatic brain injuries commonly develop increased intracranial pressure requiring surgical pl...