*Vann RD, Pollock NW, Freiberger JJ, Natoli MJ, Denoble PJ, Pieper CF. Influence of bottom time on preflight surface intervals before flying after diving. Undersea Hyperb Med 2007; 34(3): 211-20.
OverviewThe three specific goals of the Flying After Diving project are:
The results of all our related studies are pooled to form a decompression model calibration data set.
The FAD Calibration study will be limited to tests of only a few specific dive-altitude combinations because of time and cost considerations. A comprehensive medical screening questionnaire and medical examination by a physician will ensure that subjects meet the physical requirements for participation. The studies are conducted in the hypo-/hyperbaric chambers at Duke University.
Subjects will perform light exercise continuously throughout the simulated dive, randomly either while dry or immersed as randomly assigned. Dive depths between 60 and 100 feet of seawater (fsw) or between 18 and 30 meters of seawater (msw) will be used with bottom times selected from the U.S. Navy dive tables. Following a planned surface interval, subjects will complete a resting exposure of four hours at a pressure equivalent to an 8,000-foot (2,438-meter) altitude. This is the maximum altitude (minimum pressure) allowed in commercial, pressurized aircraft.
The outcome of each experimental dive-surface interval-flight profile will be evaluated statistically to determine the next profile to be tested. Three alternatives are possible: (1) accept the surface interval without additional testing and begin testing a shorter surface interval; (2) reject the surface interval from further testing and begin testing a longer surface interval; or 3) test a different dive-surface interval-flight profile.
Two experiments, with up to four subjects per experiment, are conducted monthly. Exercise will be administered using a specially designed leg cycle ergometers for both dry and immersed exercise. Subjects are certified scuba divers or experienced in hypo-/hyperbaric exposures who are qualified upon completion of: 1) a medical history review and physical examination by a hyperbaric center physician; 2) body composition assessment; and 3) baseline ultrasonic measures. Subjects will be monitored for bubbles throughout the study with precordial Doppler (sound only) and transthoracic echocardiographic (two-dimensional picture) ultrasound for the presence of bubbles in the circulation.
ParticipationParticipants must be:
pregnancy (Females of child-bearing age must allow a small blood sample to be drawn for pregnancy testing.) pneumothorax asthma that is active and requires medication (Check with study physician.) chronic seizure disorder certain chronic diseases (Check with study physician.) recent joint surgery (within six months of study date)
Subjects are eligible for more than one study as the profiles change, but a subject may participate only once in a given dive-surface interval-flight profile.
Restrictions prior to the study:
Restrictions following the study:
Participants will receive prorated compensation for a total of $120 per trial. Completion of the study is required for full payment. This includes brief follow-up interviews on each of the first two mornings after the study flight. The medical outcome is just as important as the dive. Prorated compensation is $45 for the dive day, $45 for the flight day, $15 for the first morning-after health check, and $15 for the second morning-after health check. (Note: Volunteers disqualified after completing the baseline evaluations but before beginning the dive will receive a total compensation of $20.)
DAN membership and Preferred Plan insurance will be provided for participants who complete the dive phase of the study if they are not currently covered. (Current DAN Members with lesser insurance coverage will have their level increased to Preferred for the remainder of their annual membership cycle.)
Meals will be provided at the chamber during the study, and some meals may be compensated up to $7 for lunch and $13 for dinner. Individuals living outside a 60-minute driving radius from Duke University are asked to stay overnight following the dive and flight (room cost is covered by the study on a shared basis).
Please refer to the Study Cancellation Policy.
The FAD Calibration Study is currently scheduled for the following dates:
Oct. 27-28, 2011
Nov. 10-11, 2011
Dec. 1-2, 2011
Dec. 8-9, 2011
Sign Up or Ask Questions
If you would like to participate in this study, complete a Medical History Form and return it by email to firstname.lastname@example.org, by fax to +1-919-493-3040, or mail to DAN Research, 6 West Colony Place, Durham, NC 27705.
For additional information, contact DAN Research at +1-919-684-2948 ext. 260 or send a message.
Download directions to the Duke hyperbaric center.
Frequently Asked QuestionsWhat is the study about?
How do we receive our compensation?
Where do we go diving?
Do I bring any gear? What should I wear?
What is a typical study like?