EBSDC Component 2

<< Predictive Studies Programs

PREDICTIVE STUDIES VII (PS VII): Interactions of Hyperoxia, Exercise, and Immersion in Neurologic O2 Poisoning.
Major Category: Oxygen toxicity and oxygenation. Immersion. Exercise. (PS VII)

Background: Predictive Studies VII includes a Series of related Experiments concerned with determining bases for the known but unexplained effect of exercise in decreasing latency of convulsions in hyperoxic exposures, in dry or in-water immersed situations.

The Experiments Series is cited as Subcategories 1 - 11. It included development of abilities for performance of ergometer work, in submerged states, with integrated measurements of pulmonary ventilatory responses, end-tidal carbon dioxide partial pressures, and the middle-cerebral artery blood flow velocity index of brain blood flow. The Series included effects of O2 breathing at 2.0 ATA during incremental degrees of exercise, related pulmonary ventilation, arterial blood PCO2 and brain blood flow responses to the hyperoxic exercise.

It included effects of hyperoxic immersion on respiratory response to inspired CO2, and resultant arterial blood PCO2.

Integration and analysis of composite results is described in reports, including derivation and modeling of brain "hyperoxic dose" in hyperoxic exercise.

CONTENTS

1	O2 toxicity: exercise/O2 interactions during hyperoxic work in dry chamber.
2	Methods: Calibration of middle cerebral artery blood flow velocity by Transcranial Doppler vs ¹³³Xe brain blood flow over wide P_aCO2 range.
3	Brain blood flow velocity responses to hypercapnia at rest and during exercise at 1.0 ATA.
4	Repeated progressive exercise protocols: 3 times in succession
5	Development and characterization of underwater ergometer system.
6	Development of online methods for measuring/monitoring physiological responses in fully immersed Subjects.
7	Methods: comparison of glass and plastic syringes re: rates of gas loss from contained solution.
8	Preliminary study, comparison of Middle Cerebral Artery Blood Flow Velocity (MCAvel) and ventilatory responses to exercise
9	Partial and total immersion and hypercapnia
10	Partial and total immersion and exercise.
11	Hyperoxia, exercise, cerebral circulation.

08 February 2000 01:35:07 PM

For information, contact EBSDC: clambert@mail.med.upenn.edu