DEPARTMENT OF ANESTHESIOLOGY ANNUAL REPORT

Adjuncts to Recompression Therapy for
Severe Dysbaric Diseases (Dr.
Thalmann)
A literature search has been conducted
to identify pharmacological
adjuvants, which might be useful in
treating decompression illness. The
focus has been on the scenario in
which there is a long, unavoidable
delay in obtaining recompression, in
order to identify pharmacological
agents that might reduce the negative
effect of the long pre-treatment surface
intervals on morbidity.
Analysis of the Effectiveness of Hyperbaric
Oxygen Treatment for Radiation
Cystitis (Drs. Hendricks, Moon, Stolp,
Dear, Piantadosi)
Numerous published reports support
the use of HBO for the treatment
of radiation-induced cystitis. However,
neither the optimum treatment pressure
nor the optimum number of treatments
are known. To determine these factors,
a meta-analysis is being performed
using a database that includes patients
treated at Duke and published series.
Biological Effects of Low Frequency
Sonar Signals on Divers (Drs.
Thalmann, Gerth)
Low frequency sonar is a new
method of communication between
submarines. Theoretical concerns
about possible deleterious biological
effects are being investigated.
Development of Efficient Oxygen Delivery
Systems for Field Use (Drs. Vann,
Pollock)
Testing of several rebreathing
circuits to determine the optimum
design to maximize inspired PO 2 and
minimize inspired PCO 2 at sea level and
simulated altitudes of 15,000 and 30,000
feet, under conditions of rest and
exercise.
Effect of Altitude Hypoxia and Hyperbaric
Oxygenation on S-nitrosohemoglobin
Concentration and Vascular Tone in
Humans (Drs. Piantadosi, Moon,
Stolp, Dear, Carraway, McMahon,
Mr. Archibald)
A joint study with members from
the Department of Medicine (Drs.
Piantadosi, Carraway, McMahon) has
been completed to examine the
hypothesis that PO 2-related changes
in pulmonary and systemic vascular
resistance in humans are mediated
by S-nitrosohemoglobin. This will be
followed by a study of prolonged exposure
to 15,000 feet altitude with volunteers
instrumented with arterial and
pulmonary artery catheters.
Effect of Ascent Rate on Venous Gas
Embolism and Decompression Illness in
Scuba Divers (Drs. Vann, Denoble)
With support from the Divers Alert
Network, a large series of chamber trials
is underway to study the effect on
decompression illness and venous gas
embolism of ascent rates, which have
in the past been recommended as low
as 10 ft/min and as high as 60 ft/min.
Ascent rates of 10 fpm and 60 ft/min
will be tested in a series of dive profiles
over a range of no-stop bottom times at
a depth of 100 fsw.
Establishing a Multi-Center, Multi-
Disciplinary Program for Improving Diver
Thermal Protection Hardware in Warm
and Cold Water (Drs. Thalmann, Gerth)
The goal of this project is to establish
a long range, ongoing, multi-disciplinary
program to address the thermal
protection needs of the military diver.
Current thermal protection methodology
has several shortcomings; passive
garments are bulky and provide inadequate
protection to the hands and feet,
active systems have yet to be designed,
which are compatible with current mission
profiles. In addition, little attention
has been paid to the thermal problems
encountered by divers who must dive
in hot water, such as in the Persian
Gulf. We will combine literature
searches with direct contacts of those
in the field to identify deficiencies and
possible methods of addressing them.
The centerpiece of this effort will be
a symposium where we will invite
scientists and engineers from various
disciplines to discuss new cutting edge
CLINICAL ACTIVITIES
technology that may have current application.
We will also identify any physiological
areas which may not have
been sufficiently investigated and
which may impact on the design of protective
garments. One example would
be the effect or regional heating of the
hand and forearm on heatflow from the
rest of the body. Once we have an idea
of what types of technologies are available,
and which types of institutions
may have a role in applying that technology
to operational problems we
will develop a BAA, which will solicit
research proposals targeted at applying
these technologies to existing problems.
This BAA will be turned over to the program
sponsor and form the basis of a
follow on R&D program. In addition
we will summarize our finding in a
report for future reference.
Field Measurement of Plasma Glucose in
Insulin-Requiring Diabetics During Scuba
Diving (Drs. Dear, Moon, Feinglos,* Ms.
Uguccioni, Mr. Dovenbarger)
*Division of Endocrinology, Department
of Medicine
Insulin-requiring diabetics have
traditionally been excluded from scuba
diving because of the risk of severe
hypoglycemia underwater. Field studies
in insulin-requiring diabetics are underway
to determine the probability of
hypoglycemia during recreational scuba
diving under tightly controlled circumstances.
A database of 500 man-dives
has been established, which includes
plasma glucose measurements before
and after each dive.
Influence of Surfactants on Bubble
Formation in Gelatin (Drs. Vann,
Gaskins, Mr. Hobbs)
The theoretical effects of surfactants
on bubble formation are widely
cited with regard to the mechanisms
of decompression sickness, but no data
are available to test the theory. We are
studying the effects of surfactant concentration
on bubble formation in
gelatin.
CLINICAL ACTIVITIES 57