Biomedical subjects

E Trautman

Publications and source records attributed to E Trautman.

4 recordsLinked to original sources

PubMed1995

Preferred viewing distances for handheld and structurally fixed displays.

This research was conducted to define viewing distance characteristics of individuals engaged in ordinary reading tasks. Specific attention was directed to assessing the potential relationship between observed distance and individual resting point accommodation. Consistent, statistically significant differences were observed across variable handheld and structurally-fixed hardcopy display configuration conditions. Relationships between observed viewing distance and resting point accommodation were not apparent. These findings suggest that simple eye-to-display viewing distance is fundamentally different for handheld text presentations and for the same text presented in a configuration similar to that of a video display terminal.

Accommodation, Ocular↗

PubMed1988

Synthetic smoke with acrolein but not HCl produces pulmonary edema.

The chemical toxins in smoke and not the heat are responsible for the pulmonary edema of smoke inhalation. We developed a synthetic smoke composed of carbon particles (mean diameter of 4.3 microns) to which toxins known to be in smoke, such as HCl or acrolein, could be added one at a time. We delivered synthetic smoke to dogs for 10 min and monitored extravascular lung water (EVLW) accumulation thereafter with a double-indicator thermodilution technique. Final EVLW correlated highly with gravimetric values (r = 0.93, P less than 0.01). HCl in concentrations of 0.1-6 N when added to heated carbon (120 degrees C) and cooled to 39 degrees C produced airway damage but no pulmonary edema. Acrolein, in contrast, produced airway damage but also pulmonary edema, whereas capillary wedge pressures remained stable. Low-dose acrolein smoke (less than 200 ppm) produced edema in two of five animals with a 2- to 4-h delay. Intermediate-dose acrolein smoke (200-300 ppm) always produced edema at an average of 147 +/- 57 min after smoke, whereas high-dose acrolein (greater than 300 ppm) produced edema at 65 +/- 16 min after smoke. Thus acrolein but not HCl, when presented as a synthetic smoke, produced a delayed-onset, noncardiogenic, and peribronchiolar edema in a roughly dose-dependent fashion.

Acrolein↗

PubMed1986

Time dependence of the oxygen cost of force development during systole in the canine left ventricle.

To determine whether the oxygen cost of force development in the canine left ventricle is constant throughout systole, we inserted fluid-filled Latex balloons into eight isolated canine left ventricles perfused via support dogs. Balloon volumes were varied by a hydraulic servoactuator designed to withdraw preset volumes rapidly (0.5 ml/msec) beginning at a specified ejection pressure. Oxygen consumption was related to force-time integrals for 9-12 different ejections patterns formed by ejecting three or four different volumes from the same end-diastolic volume, each ejection beginning at three different pressures, isovolumic beats with four or five different end-diastolic volumes, including those used for the ejections. The force-time integral vs. oxygen consumption data are nonlinear for ejections that began at low pressures, with oxygen consumption exceeding that predicted from regression lines fitted to the isovolumic data. This difference appeared to peak at relatively low force-time integrals and then curve back to converge with the isovolumic line. This pattern was not evident for ejections that began late in systole. Although these results suggest that the energy required for force development is greater than expected early in systole, they also are consistent with the hypothesis that oxygen consumption is a function only of instantaneous ventricular volume.

Animals↗

PubMedDate not supplied

Contribution of measurement system artifacts to systolic spikes.

A clinical study was conducted to determine if the systolic spike often observed in an invasive blood pressure display originates in the measurement system. The clinical system consisted of a catheter, stopcocks, 4 ft of tubing, an amplifier (containing a 12-Hz low-pass filter), and a continuous flush device. A second transducer was connected directly to the patient's catheter, in parallel with the clinical system. Its output was conditioned by an amplifier modified to exclude the low-pass filter. Simultaneous measurements were taken from both transducers, recorded, and later analyzed. A comparison of the traces in the time domain, as well as an analysis of the signals in the frequency domain, suggests that the systolic spike did not originate in the pressure tubing or in the amplifier system.

Blood Pressure↗