Chapter 31 

 DETERMINATION OF DISSOLVED GASES IN BODY FLUIDS 



W. F. Mazzone 

 Submarine Medical Center 

 New London, Connecticut 



G. F. Bond 



Special Projects Office 



Washington, D. C. 



J. W. Swinnerton 

 Naval Research Laboratory 

 Washington, D. C. 



INTRODUCTION 



One of the most difficult problem areas confronting the physiologist today is the lack of a 

 simple, accurate means of determining the inert- gas tension in tissue. In hyperbaric physiol- 

 ogy, decompression schedules may be based on mathematical calculation; however, the validity 

 of such schedules can be established only on an empirical basis. Although it is common prac- 

 tice to introduce safety factors in favor of the diver, it is not feasible to include contingencies 

 covering all individual variations. 



This study was undertaken during the early phases of preliminary pressure exposures 

 conducted at the Submarine Medical Research Laboratory, Submarine Medical Center, Groton, 

 Connecticut, to determine its acceptability for a test program to be scheduled during Sealab II. 

 The preliminary results were extremely encouraging, and therefore scheduled for the Sealab 

 II operation. 



The application of gas chromatography for determination of small amounts of dissolved 

 gases in solution, as reported by John Swinnerton, et al. of the Naval Research Laboratory, was 

 considered to be the most practical means of determining the dissolved- gas levels in urine. 



The equipment consists of all- glass sample chamber in which the dissolved gases are 

 stripped from solution by inert carrier, a four- way bypass valve, a commercially available gas 

 partitioner, and a 1-mv recorder. Calibration for routine work is accomplished by carrying 

 out the determination on a sample of water saturated with pure gas at a known temperature and 

 pressure. 



The partitioner may be fitted with two columns, each containing a separate packing materi- 

 al. Generally in the evaluation of respirable gases, column one contains a material called 

 diethyl hexyl sebacate, which removes or retards the carbon dioxide. Column two contains 

 molecular sieve 13x, where oxygen and nitrogen are separated. 



With argon gas as the inert carrier, it is possible to analyze for helium concentrations in 

 urine. With argon, the sensitivity for oxygen- nitrogen separation is considerably diminished. 



Note: The introductory remarks are authored by Captains Bond and Mazzone, while the report 

 itself is by Dr. Swinnerton. 



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