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E Rohr

Publications and source records attributed to E Rohr.

6 recordsLinked to original sources

Are drivers more likely to injure their right or left foot in a frontal car crash: a crash and biomechanical investigation.

In this study we hypothesized that for frontal crashes, the driver was more likely to sustain foot injury than the front seated passenger and the right foot was more likely to be injured than the left because the driver's right foot was positioned in dorsiflexion and eversion during the crash and less able to tolerate crash forces. Seventeen CIREN frontal crashes were studied to document the circumstances and resulting foot injuries. NASS data was sampled to determine frequencies of injury to foot side and occupant position. Biomechanically, matched pairs of cadaveric feet were tested in compression with one in dorsiflexion, and the other, dorsiflexion, and eversion. Results showed that drivers were more likely than passengers to sustain a foot or ankle injury and this was almost exclusively due to a higher frequency of right foot injuries in drivers. Braking, with significant toepan intrusion, was associated with an increase in both right and left foot injuries in drivers. Biomechanically, 9 of 15 pairs tested provided useable data. There was a significant decrease in load to failure between specimens forced into dorsiflexion and eversion (mean, 4107 N, sd = 1630 N) compared with dorsiflexion alone (mean, 6468 N, sd = 2435 N, p = 0.001). The majority (16 of 17) of foot injuries in the CIREN cases were to drivers of which 13 injured their right foot and ankle. An implication of this work is that if thresholds based on data from dorsiflexion and compression loading are used to predict foot and ankle injury in frontal crashes they may not represent that population of drivers who are braking at the time of the crash and could suffer injuries at forces lower than current threshold values.

Accidents, Traffic↗

Breathing pattern associated with respiratory comfort during automatic tube compensation and pressure support ventilation in normal subjects.

BACKGROUND: Automatic tube compensation (ATC) is a new option to support spontaneously breathing tracheally intubated patients. We have previously demonstrated an increased respiratory comfort compared to pressure support ventilation (PSV) in volunteers. Here we characterized the breathing pattern during ATC associated with respiratory comfort in comparison to PSV. Furthermore, we studied whether ATC can be substituted by a simple modification of PSV. METHODS: We exposed 10 volunteers breathing through a 7.5 mm endotracheal tube via mouthpiece to PSV with 1) immediate and 2) delayed pressure rise and to 3) ATC. Immediate changes of the respiratory pattern after mode shifts were analyzed in detail. Furthermore, the volunteers were instructed to indicate changes in comfort after transitions between these modes as increased, unchanged, or decreased. RESULTS: Decreased comfort was associated with a substantial increase of tidal volume, minute ventilation, gas flow, and pressure. No differences in respiratory comfort were perceived between immediate and delayed pressure rise during PSV. CONCLUSION: PSV resulted in excessive tidal volumes and airflow, which was perceived as discomfort. This cannot be avoided by a delayed pressure rise but can be by the more comfortable ATC. ATC seems to adapt better to the ventilatory demand than PSV.

Adult↗

Respiratory comfort and breathing pattern during volume proportional assist ventilation and pressure support ventilation: a study on volunteers with artificially reduced compliance.

OBJECTIVE: To assess respiratory comfort and associated breathing pattern during volume assist (VA) as a component of proportional assist ventilation and during pressure support ventilation (PSV). DESIGN: Prospective, double-blind, interventional study. SETTING: Laboratory. SUBJECTS: A total of 15 healthy volunteers (11 females, 4 males) aged 21-31 yrs. INTERVENTIONS: Decreased respiratory system compliance was simulated by banding of the thorax and abdomen. Volunteers breathed via a mouthpiece with VA and PSV each applied at two levels (VA, 8 cm H2O/L and 12 cm H2O/L; PSV, 10 cm H2O and 15 cm H2O) using a positive end-expiratory pressure of 5 cm H2O throughout. The study was subdivided into two parts. In Part 1, volunteers breathed three times with each of the four settings for 2 mins in random order. In Part 2, the first breath effects of multiple, randomly applied mode, and level shifts were studied. MEASUREMENTS AND MAIN RESULTS: In Part 1, the volunteers were asked to estimate respiratory comfort in comparison with normal breathing using a visual analog scale. In Part 2, they were asked to estimate the change of respiratory comfort as increased, decreased, or unchanged immediately after a mode shift. Concomitantly, the respiratory pattern (change) was characterized with continuously measured tidal volume, respiratory rate, pressure, and gas flow. Respiratory comfort during VA was higher than during PSV. The higher support level was less important during VA but had a major negative influence on comfort during PSV. Both modes differed with respect to the associated breathing pattern. Variability of breathing was higher during VA than during PSV (Part 1). Changes in respiratory variables were associated with changes in respiratory comfort (Part 2). CONCLUSIONS: For volunteers breathing with artificially reduced respiratory system compliance, respiratory comfort is higher with VA than with PSV. This is probably caused by a better adaptation of the ventilatory support to the volunteer's need with VA.

Adult↗