Scientific papers 1960 - 1979
This document was published in 1965. It present
developments in decompression theory subsequent to the
Dwyer report
Robert D. Workman was a medical doctor of the U.S.Navy
Experimental Diving Unit. He made a systematic review of
decompression models, including previous research
performed by the U.S. Navy, notably those from
Yarbrough in 1937 and Dwyer in 1955.
He is the inventor of the M-values concept that established
a linear relationship between depth pressure (or ambient
pressure) and the tolerated inert gas pressure in each
"tissue" compartment. This concept is applied by a variety
of modelers today.
This document describes experiments made to test
assumptions underlying the conventional methods for
calculating decompression schedules:
1.
There is a critical limit to the supersaturation of a tissue
by a gas
2.
No gas is formed in the tissues of a subject who does
not develop symptoms of decompression sickness.
This document explains effects observed during
simulated diving experiments, where the subjects
have experienced intense itching, confluent
maculopapular skin lesions, and a severe vestibular
derangement with vertigo and nystagmus, when a
gas mixture containing nitrogen or neon was being
breathed while a second inert gas, helium, was
present in the surrounding environment. Thus, it
describes the effects of counterdiffusion.
Abstract:
To gain insight into the pathogenesis of warm-water
immersion dermatoses, an experimental technique was
developed whereby skin sites on human subjects could be
continuously exposed to water for varying time periods
simulating actual expo ·ures receivedby affected patients.
Clinical and histologic observations of test sites exposed to
water for 72 to 144 hours revealed intense subacute
dermatitis. Contrary to established beliefs, the induction
and intensity of responses were not dependent upon
increases in skin surface pH or bacterial population.
Moreover, neither post hydration anhidrosis nor miliaria
were found, although stratum corneum hydration and
maceration · were pronounced.
It is proposed that either water itself or some
unrecognized potentially toxic natural surface substance is
responsible for the dermatitis.
This document is a synthesis of descriptions of HPNS that
have been published in 1970 & 1971:
• Bennett and Towse 1971
• Fructus and Agarate 1971
• Fructus et al. 1971;
• Fructus and Conti 1971
• Fructus and Vigreux 1970
Doctor Bennett is a physiologist who was employed by
the royal Navy, and also headed the Defence and Civil
Institute for Environmental Medicine (DCIEM) in Canada.
He is the founder and former president of the Divers Alert
Network (DAN), a non-profit organization devoted to
assisting scuba divers.
He is also the author of numerous diving medical books,
and is a recognised diving medical expert.
In association with Hennessy, Hempleman developed a
complex formula taking into account the diffusion, the
surface tension around the bubble, the elasticity of tissues,
the perfusion, the voltage of the gas in the liquid to
describe the magnification of bubbles and their circulation
in the body.
In contrast to the Haldane model, it is considered that the
gas diffuses through the alveolar walls to dissolve in the
blood and broadcasts also in cartilage (only organic fabrics
retained in the model). This model is said “by diffusion”
David E. Yount (US navy at Hawaii) is a developer of the
Variable Permeability Model (VPM) that believes that
“nuclei” of gas need to be present to trigger the formation
of bubbles during or after decompression. The “nuclei” or
gas pockets occur in the natural state and may develop
from the gas nucleus trapped in small hydrophobic
crevices or be generated by tribonucleation. It is thought
that the surface tension at the external of the bubble
creates a sort of “skin”, which is the interface between the
free gases inside the bubble and the liquids/dissolved
gases in the tissue compartments. The skin of the bubble
can be compared to an elastic membrane with
microscopic holes which are closing gradually when the
size of the bubble decreases and opening gradually when
the size of the bubble increases: The permeability of the
bubble varies, that is why this model is called “Variable
Permeability Model”.
In this article, a model is investigated in which stability is
maintained by surface-actiive skins of varying gas
permeability.
This document is the final report of a workshop performed
on the 13 and 14 of November 1979 under the direction
of doctors Lambertsen and Bornmann.
This document is a conference made by Doctor Christian
J. Lambertsen to describe the concept of isobaric
counterdiffusion and bind together elements determining
decompression safety.
This document was published in 1966.
Brian Andrew HILLS (1940 - 2006) was a physiologist who
did fundamental researches regarding decompression
models.
He is the author of the "thermodynamic decompression
model", which is based on the concept of “unsaturation”
and in which decompression is controlled by the volume
of gas bubbles coming out of solution.
This model suggests deeper decompression stops than the
models based on Haldane's theory. It is used to design
new decompression tables.
Hills is also the author of numerous publications regarding
decompression problems.
This document was published in 1968. It describes
experimentations made by exposing a symptom-free
individual with a history of retrobulbar neuritis to 2.0
atmospheres (atm) of inspired oxygen for six hours to
obtain transient diminution of vision.
The document explains two distinct processes that
appeared to have been involved in producing the visual
disturbance.
One was considered an acute expression of oxygen
effect on neuronal elements by direct action on enzymes
or limitation of nutrient flow.
A second process was considered to have been a
recrudescence of retrobulbar neuritis.
The authors concluded that this case emphasized the
need for a detailed evaluation of all individuals exposed
to oxygen at greater pressures than atmospheric
pressure.
Doctor Christian James Lambertsen (1917 - 2011) is
known for his works on the effects of hyperbaric oxygen
and was the 1st scientist to describe the mechanism of
counterdiffusion. He is associated with many papers
published on this website.
This article was written to support the famous book
“Decompression Sickness: The Biophysical Basis of
Prevention and Treatment” (published by John Wiley in
New York and London), where the Thermodynamic
approach was explained in detail.
It describes the problems arising with decompression and
their approach by Brian Hills.
In this article, Brian Hills described the implication of
supersaturation and counterdiffusion for bubble
formation. He said that it could explain the occurrence of
decompression sickness when decompression is normally
not called for.
This document, published in 1978, describes
experimentations made during the seventies in support of
US Navy and the NASA activities with the particiaton of
the University of Pennsylvania, the U.S. Naval Medical
Research Institute, the U.S. Naval Submarine Medical
Center, the NASA Manned Spacecraft Center, the
University of Florida at Gainesville, and the Virginia Mason
Hospital at Seattle.
This study discusses the occurrence of incapacitating
vestibular dysfunction in men breathing mixes such as
nitrogen-helium-oxygen or neon-helium-oxygen mixtures
while surrounded by helium.
These symptoms were identified along with dermal gas
lesions and continuous venous gas embolization as part of
the isobaric counterdiffusion phenomenon, which is a
significant hazard in manned undersea activities.
Author: Edvard A. Hemmingsen.
Various solutions of surfactants and electrolytes were
equilibrated with argon at gas pressures up to 202 atm
and then decompressed to atmospheric pressure while
observed visually or cinematographically for the
occurrence of bubbles.
"U. S. Navy operational diving was computed for years
1958, 1960, and 1961. A comparison was made between
the incidence using the old U. S. Navy air decompression
tables (1958) and the revised U. S. Navy air
decompression tables (1960, 1961). Incidences were also
computed for dives equal to or greater than 100 feet and
less than 100 feet.
Using the Doppler detector implanted on the pulmonary
artery or posterior vena cava in sheep and goats, the team
demonstrated the presence of gaseous emboli in all
Haldane model.
"In the present investigation of diving bradycardia in the
human subject, the cardiovascular responses to breath-
holding have been examined both in air and in water at
various depths of immersion. The results provide an
explanation of the mechanism of the response. A
preliminary account of this work has been presented to
the Australian Physiological Society (Harding & Roman,
1961).
Author: Leslie A. Guildner
The values of thermal conductivities being reported in this
paper were obtained by the author at the Massachusetts
Institute of Technology. They were to have been part of a
more extensive set of measurements, but further work was
not completed with this equipment because the author
came to the National Bureau of Standards. Even though
the number of these results is small, the measurements
are thought to be sufficiently accurate to be useful.
Decompression limits for compressed air determined by
ultrasonically detected blood bubbles.
The direct decompression limits for a group of divers over
a range of pressure-time air exposures was determined
using ultrasonic detection of venous gas emboli (VGE). In
addition to dry chamber exposures, ranging from 233 ft
for 7 min to 25 ft for 720 min, the authors exposed six
divers to open ocean dives at 165 ft for 10 min. Findings
demonstrated a strong individual propensity to form
VGE, correlating with susceptibility to bends.
The primary purpose of this review was to examine the
evidence for pulmonary oxygen toxicity in man when
oxygen is administered at normobaric conditions or the
equivalent partial pressure. However, because of the limits
to experimental evidence in man, the effects of prolonged
administration of high concentrations of oxygen in
experimental animals and primates were also discussed,
where it was relevant to evaluating the evidence of
pulmonary oxygen toxicity in man.
This document, published in 1971, is a description of the
various phases of a simulated dive at 458m conducted at
the Experimental Hyperbaric Centre in Marseilles with two
men from the British Royal Naval Physiological Laboratory,
aged 26 and 20 years.
A compression rate of 100 ft (30 5 m) in 6 minutes was
used and broken into stages to permit the study adaptation
and recovery to HPNS. The ascent rate was 40 ft (12 m) per
hour and was found to be too fast.
As a comparison, the ascent rate from 350 msw to 20 msw
of a modern table such as the NORMAM-15 is 50 min/msw
(1.2 m/hr), so ten times slower.
This document explains the reasons and the process
used to implement the method for calculating the
Unit Pulmonary Toxic Dose (UPTD). The tables
resulting from these calculations have been used
from this time, and still by many diving organizations
today, even though scientists such as Barbara Shykoff
and Ran Arieli have proved that this concept, done
with the scientific data available during the sixties,
has to be reviewed.
The elements from this paper are integrated into our
surface-supplied handbook to explain this concept.
Dr. Wright worked closely with Dr. Lambertsen, who
launched this concept and supported this paper.
Authors: John B Hartley, George m Santangelo, Howard
Rasmussen, Howard Goldfine
This study examined membrane-related oxygen poisoning
in Escherichia coli K1060 and its parent strain, K-12 Ymel. It
concluded that the kinetics of oxygen toxicity in E. coli are
dependent upon the particular unsaturated fatty acyl
chain composition of the membrane, that the membrane
composition influences the rate-limiting step in hyperbaric
oxygen toxicity, but that a direct structural effect of
hyperbaric oxygen on the membrane lipid, such as
oxidation of the unsaturated acyl chain moiety, is unlikely
in these cells.
A clinical, radiological and statistical survey has been made
of decompression sickness during the construction of the
Dartford Tunnel. Over a period of two years, 1,200 men
were employed on eight-hour shifts at pressures up to 28
pounds per square inch (p.s.i.). There were 689 cases of
decompression sickness out of 122,000 compressions, an
incidence of 0-56%.
This paper is to be linked to the treatment of Acute
Oxygen Poisoning cases (Paul Bert effect).
Valium has been shown to be effective orally in the
control of chronic epilepsy, and when used parenterally,
we were pleased to find Valium remarkably effective for
treating “status epilepticus”. The authors, therefore,
decided to carry out an extensive study of its use in such
conditions.
Authors: T.E Berghage, J.Voromasti, E.E.P Barnard
This article reviews the US Navy and other recompression
procedures used throughout the world in 1978.
Author: Joseph C. Farmer j
This paper reports to the Undersea Medical Society the
discussions on “labyrinthine dysfunction during diving”
during a workshopheld on at Duke university medical
center (USA) in february 1973.
Author: Richard H. Strauss
Gelatin exposed to N2 at differing pressures was
decompressed to form bubbles findings are consistent
with the existence in gelatin of a spectrum of stable gas
nuclei which can b compressed or transformed into
bubbles. Results suggest that the number of bubbles and
their total volume can be-decreased, and decompression
time shortened, if the gas supersaturation pressure
remains constant for decompression of a given tissue.
Author:s Merill P. Spencer & David C. Johanson
This document was one of the 1st Paper on the use of
Doppler for detecting blood bubbles.
Author: Thomas E. Berghage
This document from the Undersea Medical Society
reports discussions logged during a Workshop held in
September 1978 and supported by the US Office of Naval
Research.
The participants were the most advanced US scientists in
decompression theory at this time.
Authors: H. Le Messurier, T. N. Smith, and W. r. Wood
The authors developed a model for behavior of specimens
in gel, and conformity with the results of an
experimentation program was demonstrated. With the
insight provided by this model, a substantial analogy
between important aspects of the behavior of gel and
tissue was claimed, and application of this model to the
refinement and development of diving and
decompression procedures was proposed.
This document is the summary of a workshop held in
1976 between doctors and specialists of decompression
to share knowledge and set up bases for developing
decompression tables.
Hamilton et al. conducted experiments to see whether
neon in mixed gas was suitable. The mixture was
composed of 25% helium and 75% neon, to which
oxygen was added. The team modified classical theory to
fit existing data, mainly from their experience with helium,
to develop the decompression tables. The resulting
decompression schedules proved to be unexpectedly
troublesome, causing sensory problems and delayed
effects.
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Author: P. Paulev
This document raises the question of whether
decompression sickness is unlikely for skin divers, given the
limitations in depth and duration of submersion that
prevent significant nitrogen absorption and restrict access
to compressed air supply at depth.
This document provides a collection of papers related to
the main topic of the DCIEM conference #73-cp960, held
in Downview, Canada, in 1973, in addition to its
proceedings.
Author: James H. Dougherty
This study aims to determine whether hydrogen is a
suitable inert gas for diving to 200 feet and to investigate
the possible improvement in ventilatory performance with
this least dense of all possible breathing gas mixtures.
Authors: Wayne A. Gerth & Edward A. Hemmingsen
Spontaneous cavitation is considered as a potential cause
of decompression accidents. Water with high gas
supersaturation can be stable without cavitation, but
increased supersaturation can lead to system failure and
bubble formation. The concentration of a gas in a solution,
which is influenced by its solubility, plays a significant role
in determining the stability of gas supersaturation in
liquids.
Authors: B. Gardette, A. Ternisien
This key document, written in French, summarizes
experimentations made by Comex on the use of Dopplers
during the years 1976 & 1977.
These operations led to the improvement of devices and
their corresponding procedures for use.
Authors: Louis D Homer, R. Clifton Bailey
Doctors Homer and Bailey conducted extensive research
on statistics for the US Navy.
This paper presents an approach to maximum likelihood
estimation (MLE) using analogies. The resulting algorithm
offers a direct and general approach to Maximum
Likelihood Estimation, simplifying the estimation process,
especially when dealing with complex likelihood functions.
Authors: William L. Hunter, Gene B. Pope, Danny A. Arsu
This document, published in 1978, aimed to improve US
Navy diving procedures. Although the incidence rate of
decompression sickness was below 0.1%, which was
considered low, it was acknowledged that accidents still
occurred and needed to be prevented.
Authors:
W.H. Spaur, E.D. Thalmann, E.T. Flynn, J.L. Zunirick, T.W.
Reedy, and J. M. Ringelberg
This document discusses experiments performed during
helium-oxygen saturation dives ranging from 150 to 1000
fsw to study the limits of multiple and extended-duration
excursions, both deeper and shallower than the storage
depth.
It was found that the distance a diver can safely ascend
without decompression is a function of depth, increasing
from 75 feet at a saturation depth of 225 feet to 180 feet
at I000 feet. Also, initiating saturation decompression
immediately after an excursion was considered safe.
Publisher:
The Undersea and Hyperbaric Medical Society (UHMS)
This workshop, held in Bethesda, Maryland, from
September 6 to 7, 1978, explored the complexities of
decompression theory and provided a platform for
collaboration and knowledge exchange. The Office of
Naval Research supported it.
Although the official proceedings remain a valuable
resource, the spirit of inquiry and exploration still shapes
our understanding of underwater medicine and safety.
Authors: K.E. Kidman, G. Masurel, R. Guillerm
This document explains how to establish a databank
containing Doppler ultrasonic bubble flow data obtained
during and after the decompression of divers.
This databank can serve as a foundation for future
computer correlation studies.
Author: Thomas D. Kunkle
This document pertains to experiments on the formation
of bubbles when gas dissolves in liquid and becomes
supersaturated.
The findings are that:
•
Viscosity significantly influences bubble growth.
•
Pressure and diffusion also affect the bubbles' behavior
and the gas transfer rate.
•
The solubility of the gas also plays a crucial role in the
dynamics of bubbles.
