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Machine-read from the scan, so expect some errors. Lines that couldn’t be read are left out.
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From: Paul Meyer Institutional Review Board I ! ' I Human Subjects Experiments with Air Tagged with Radioisotopes This memo isin answer t o your request o f February 23, 1986 for more Iwill attempt t o address the issues youi n formation on the subject matter. raised point by point. Why are experiments done? What isthe Navy's Interest ? Decompression sickness problems remain the most important limitations of present and proposed operational Navy diving. Central Navy tasking to the medical laboratories recognizes the problem. It provides general guidance, such as "produce an algorithm for special warfare divers to perform complex dives, outside the current decompression tables," and allocates stable funding o f about 850OK per year (Ref.3). Much of that funding i s consumed by computational work and trial and error human experiments in the large high pressure chambers atthe Naval Medical Research Institute(NMRI)in Bethesda, Maryland. 60th theP.I.(Ref.9) and the Head of Diving Medicine (Ref. 1) believe that the proposed human experiments can provide a needed quantum increase i n basic understanding to minimize future trial and error Why a t LLNL? Some years ago, on the urging of LLNL's Hazards Control Department, I developed a radioisotope facility at the LINAC t o produce camera imaging system was implemented t o study the effect of ozone on lung function of dogs and humans. This project was i n cooperation with the University of Washington Medical School, funded by NIH and EPA, and approved by LLNL's Finance Committee. The capability and expertise gained was unique in the United ' States and lead to the current joint research program with the Navy. At this time,there exists,to our knowledge, no other laboratory where this scientific investigation could be conducted without a lengthy COLLECT~ON Institutional Review Board IRB Protocol File With ga dio active Gases
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Barton L. Gledhill -2- April 12, 1988 Decompression sickness risks; what are they and how often do they of cases of decompression sickness per year i n the Navy. the number of dives is listed as approximately 16,200 for the Navy alone. Overall incidence rate was found t o be 1.25%; the incidence rate for individual schedules, having more than 5 0 dives, ranged from 0-4.8% (Ref. 4). Several percent of these cases left permanent disabilities, such as central nervous system dysfunction, residual paralysis, sensory loss below the knee and impotence are some of the more common ones. systematic records are unavailable, it is said that civilian divers using Navy decompression tables under less controlled conditions, experienced an order of magnitude greater problems. Furthermore, a new Navy need is for a general decompression computer algorithm for SEAL teams t o operate on Their mission success depends on a good calculational approximation for gas exchange kinetics in humans. The present decompression tables are known to result i n dozens Radiation exposure risk? The dose received by each subject i s calculated using actual lung volume and time elapsed from isotope production t o beginning and end of exposure. absolute specific activity measurements achievable under full accelerator beam power condition, extrapolated back t o beam-off time. I n practice, the actual dose is always less than the maximum, because of elapsed time t o gas uptake and generally lower than maximum beam power. Due t o the necessary gas preparation procedure, the time t o uptake is at least one half-life of the N-13. Steve Homan (health physicist, LLNL Hazards Control) addresses the cancer risk (Ref. 2). His conservative estimates are based on 400mr t o the lung and generally accepted international statistical methods. The expected number of cancer fatalities for a set of 20 subjects associated with this procedure os 0.0002, i.e. t w o in 10,000. This must be compared with a natural expected value of five cancer fatalities for the group, i.e., 20 x 0.25 fatalities per person. The maximum dose of 400mr is based on Why use human subjects? Animal work with radioactive gas has been performed (Ref. 6) and the results have been partially implemented in new human decompression procedures (Ref. 7 and 8). However, the work done at LLNL with humans (Ref. 5) showed a striking qualitative difference in outcome, that perplexes diving physiologists and makes direct human studies
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1) letter from Dept. ofthe Navy by Capt. E. T. Flynn, Feb. 8, 1988. 2) Internal Memo from Steve Homan, LLNL Hazards Control Dept., References previously submitted 3) " Scientifically Based Decompression Tables for AIR and Mixed Gas Division, " Research and Technology Work Unit Summary, OD-DR&E(AR)636. T. E. Berghage and D. Durman,. Naval Medical Research Institute. 6) " Distribution of Xenon Gas Exchange Rates i n Dogs,0 P. K. Weathersby etal.,J. Appl. Physiol: Res pir at. Environ. Exercise Physiol. 50(6); 7) " Statistically Based Decompression Tables, 'I.A na lysis of Standard Air Dives: 1950-1970, NMRI 85-16, Naval Medical Research Institute. 8) "Equal Risk Air Diving Decompression Schedules,' NMRI 85-17 (1985). Naval Medical Research Institute, Bethesda, MD. 9) Letter from Dept. ofthe Navy by Cdr. P. K. Weathersby, Dec. 22, 1987.