Scientific papers 2019
Helium Preconditioning (HPC) recently demonstrated
beneficial properties against ischemic damage, so the
authors hypothesized that this procedure might decrease
the neurological deficits of DCS in rats.
Following the experimentations described in this report,
they found that Helium Preconditioning (HPC) resulted in
significantly decreased DCS incidence and delay of DCS
onset. It also improved animal performance on the grip
test after decompression and ameliorated decompression-
induced decrease of platelet number.
Furthermore, the incidence of abnormal Somatosensory
Evoked Potential (SSEP) waves and histological spinal
lesions was reduced by Helium Preconditioning (HPC).
Authors:
Jonathan L. Halbach, James M. Prieto, Andrew W. Wang,
Dennis Hawisher, David M. Cauvi, Tony Reyes, Jonathan
Okerblom, Israel Ramirez-Sanchez, Francisco Villarreal,
Hemal H. Patel, Stephen W. Bickler, George A. Perdrizet,
and Antonio De Maio.
Sepsis is a major clinical challenge, with therapy limited to
supportive interventions. Therefore, the search for novel
remedial approaches is of great importance.
The authors addressed whether hyperbaric oxygen
therapy (HBOT) could improve the outcome of sepsis
using an acute experimental mouse model.
Authors: Jean-Pierre Imbert, Costantino Balestra, Fatima
Zohra Kiboub, Oyvind Loennechen, & Ingrid Eftedal
Commercial saturation diving involves divers living and
working in an enclosed atmosphere with an elevated
partial pressure of oxygen (ppO2) for weeks. The divers
must acclimatize to these conditions during compression
for up to 28 days until decompression is completed.
During decompression, the ppO2 and ambient pressure
are gradually decreased; then, the divers must acclimatize
again to breathing normal air in atmospheric pressure
when they arrive at the surface. The authors investigated
51 saturation divers’ subjective evaluation of the
saturation and post-decompression phase via
questionnaires and individual interviews. The questions
were about decompression headaches and fatigue and
time before recovering to a pre-saturation state.
Authors: Jean-Pierre Imbert, Salih Murat Egi, Peter
Germonpre, & Costantino Balestra.
The risk for decompression sickness (DCS) after hyperbaric
exposures (such as SCUBA diving) has been linked to the
presence and quantity of vascular gas emboli (VGE) after
surfacing from the dive. These VGE can be semi-quantified
by ultrasound Doppler and quantified via precordial
echocardiography. However, for an identical dive, VGE
monitoring of divers shows variations related to individual
susceptibility, and, for a same diver, dive-to-dive variations,
which may be influenced by pre-dive pre-conditioning.
These variations are not explained by currently used
algorithms. In this paper, we present a new hypothesis:
individual metabolic processes, through the oxygen
window (OW) or Inherent Unsaturation of tissues,
modulate the presence and volume of static metabolic
bubbles (SMB) that in turn act as precursors of circulating
VGE after a dive.
Authors:
Alain Boussuges, Guillaume Chaumet, Nicolas Vallée,
Jean Jacques Risso & Jean Michel Pontier
Previous studies have suggested that the circulatory
system was involved in the production of circulatory
bubbles after diving. This study was designed to research
the cardio-vascular function characteristics related to the
production of high bubble grades after diving.
Authors
Simin Berenji Ardestani, Vladimir V. Matchkov, Ingrid
Eftedal, & Michael Pedersen.
The number of divers is rising every year, including an
increasing number of aging persons with impaired
endothelial function and concomitant atherosclerosis.
While diving is an independent modulator of endothelial
function, little is known about how diving affects already
impaired endothelium. In this study, the authors
questioned whether diving exposure leads to further
damage of an already impaired endothelium.
Authors:
Mitchell D. Frye, Allen F. Ryan, & Arwa Kurabi.
Like other documents in our database, this paper
describes phenomenons that apply to every person.
However, people in charge of diving and ROV teams
should be aware of the potential harm of noisy
environments during operations and when people are at
rest. This paper describes the processes of inflammation
and cochlear damage triggered by noise. It also discusses
current appropriate treatments.
Authors: Ali Erdal Gunes, Samil Aktas.
Complete blood count (CBC) is a routine diagnostic
procedure for patients and a part of routine health
inspection for healthy individuals. The effect of hyperbaric
oxygen (HBO2) therapy on CBC is not known.
The objective of this study was to determine the effects of
HBO2 on blood parameters in CBC with long-term HBO2
therapy.
Authors:
Ivana Šegrt Ribicic, Maja Valic, Joško Božic, Ante Obad,
Duška Glavaš, Igor, Glavicic, Zoran Valic.
This study aims to assess the effect of a gas mixture
composed of 50% nitrogen and 50% oxygen (nitrox 50)
or a gas mixture consisting of 1% nitrogen and 99%
oxygen (nitrox 99) on bubble formation and
vascular/endothelial function during decompression after
self-contained underwater breathing apparatus diving.
Author: Ran Arieli
In a study published in the Croatian Medical Journal, Šegrt
Ribicic et al. said that the endothelial function was
reduced after diving to a depth of 45 m seawater for a
bottom time of 20 m when breathing nitrox containing
50% oxygen, but not when breathing air or nitrox
containing 99% oxygen.
The authors of this paper claimed this was the opposite of
what they expected; it is known that endothelial function
is affected by hyperoxia.
Authors: Danilo Cialoni, Andrea Brizzolari, Michele Samaja,
Massimo Pieri, and Alessandro Marroni.
Nitric oxide plays an important role in the physiology and
pathophysiology of diving, and the related endothelial
dysfunction and oxidative stress roles have been
extensively investigated.
The scope of this study is to investigate the Nitrate and
Nitrite concentration and the total plasma antioxidant
capacity before, during and after a single SCUBA dive in
healthy scuba diving volunteers, as well as to look for
evidence of a possible relationship with venous gas
bubble formation.
Authors: Stanisław Skrzynski
In the article the author presents the specificity of
decompression of deep-sea dives in relation to methods
used in underwater works, with particular emphasis on
commercial diving in our country. In the 50 - 90 m depth
zone in the Polish offshore area, decompression was used
in underwater works (works below the depth of 50 m)
based on tables designed for bell diving. The technical,
organizational and formal conditions of these underwater
works corresponded to the national diving potential.
Authors:
Thijs T. Wingelaar, Pieter-Jan A. M. van Ooij, Paul
Brinkman, and Rob A. van Hulst
Exposure to hyperbaric hyperoxic conditions can lead to
pulmonary oxygen toxicity. Although a decrease in vital
capacity has long been the gold standard, newer
diagnostic modalities may be more accurate. In pulmonary
medicine, much research has focussed on volatile organic
compounds (VOCs) associated with inflammation in
exhaled breath. In previous small studies after hyperbaric
hyperoxic exposure several methyl alkanes were identified.
This study aims to identify which VOCs mark the
development of pulmonary oxygen toxicity.
Authors:
T. T. Wingelaar, P. Brinkman , P. J. A. M. van Ooij, R.
Hoencamp, A. H. Maitland-van der Zee, M. W.
Hollmann, and R. A. van Hulst
IAlthough hyperbaric oxygen therapy (HBOT) has
beneficial effects, some patients experience fatigue and
pulmonary complaints after several sessions. The current
limits of hyperbaric oxygen exposure to prevent
pulmonary oxygen toxicity (POT) are based on pulmonary
function tests (PFT), but the limitations of PFT are
recognized worldwide. However, no newer modalities to
detect POT have been established.
This study hypothesized that Volatil Organic Compounds
VOCs might be detected after HBOT.
Authors:
Amir Hadanny, Tal Zubari, Liat Tamir-Adler, Yair Bechor,
Gregory Fishlev, Erez Lang, Nir Polak, Jacob Bergan, Mony
Friedman, and Shai Efrati
This study is also purely medical and is published to
provide information about the role of Circadian rhythms,
which are 24-hour cycles that are part of the body's
internal clock, running in the background to carry out
essential functions which control many biological
processes in the body in both health and disease.
Authors:
Amir Hadanny, Tal Zubari, Liat Tamir-Adler, Yair Bechor,
Gregory Fishlev, Erez Lang, Nir Polak, Jacob Bergan,
Mony Friedman, and Shai Efrati
The aim of this study was to evaluate the effect of
hyperbaric oxygen therapy (HBOT) on pulmonary
functions of patients receiving the currently used HBOT
protocol.
Authors: Ran Arieli
In this document, doctor Arieli explains that lung
surfactant leaks into the bloodstream, settling on the
luminal aspect of blood vessels to create active
hydrophobic spots (AHS). As a result, nanobubbles
formed by dissolved gas at these AHS are most probably
the precursors of gas micronuclei and decompression
bubbles.
Authors: Ran Arieli
In this study, doctor Arieli proposes a new Pulmonary
oxygen toxicity (POT) index to evaluate the severity of
POT, expressed as reduced lung function or the incidence
of POT in a group of divers.
Note that, as in many studies from doctor Arieli the
concept is demonstrated using complex mathematic
functions.
Authors:
Christopher M. Myers, Jeong-Su Kim , Kevin K. McCully,
and John P. Florian
This study examined the effects of repeated long-duration
hyperoxic water immersions (WIs) at 1.35 atmospheres
absolute (ATA) on neuromuscular endurance
performance. its authors hypothesized that over five days
of consecutive, resting, long-duration hyperoxic WIs, there
would be a decrease in neuromuscular endurance
performance and tissue oxygenation with the quadriceps
muscle but not with the forearm flexors
Author: Ran Arieli
Doctor Areli introduced his concept as follows:
The concept of the unit pulmonary toxic dose (UPTD),
which is based on a modification of the rectangular
hyperbola, was proposed in response to a request for
oxygen exposure limits based on a very small amount of
research data: a point at four atmospheres absolute (atm
abs) (405.2 kPa) and the absence of known injury at an
inspired partial pressure of oxygen PO2 of 0.5 atm abs
(50.6 kPa). It was merely descriptive, without any basis in
physico-chemical or physiological mechanisms. In light of
all this, it was clear that a different model was required to
fit outcome data.
Authors:
Olivier Castagna, Cedric Bergmann, Jean Eric Blatteau.
Prolonged exposure to a high partial pressure of oxygen
leads to inflammation of pulmonary tissue and pulmonary
oxygen toxicity (POT), which is associated with
tracheobronchial irritation, retrosternal pain, and
coughing, and decreases in vital capacity (VC). The nitric
oxide (NO) concentration in exhaled gas (FeNO) has
been used as an indicator of POT, but the effect of diving
on FeNO has rarely been studied. This study assessed
alterations to pulmonary function and FeNO following a
12-h dive using breathing apparatus with a relatively high
partial pressure of oxygen.
Authors: Monika Patel, Arun Dehadaray
Acute otitis externa (AOE) is the inflammation of the
external ear. It usually presents with severe pain in the ear.
The treatment of AOE should aim in relieving pain at the
earliest. Out of the various treatment options, topical
treatment should be considered as prescribing oral
antibiotics without local treatment can cause antibiotic
abuse. Due to unavailability, cost, and compliance issues of
other topical measures,
The authors observed and proved the effectiveness of a
new modality glycerine and povidone-iodine wick in the
treatment of AOE.
Authors: Shrestha K, Shah R, Sapkota S
Otitis externa is a common painful condition presents with
generalized infection of external auditory canal, typically
reveals erythema and edema of the skin. Aural packing
plays an important role in relieving the pain and edema.
For packing either we impregnated with 10% Ichthammol
glycerine or steroid-antibiotic ointment.
Authors:
Piotr Siermontowski, Wojciech Kozłowski, Katarzyna
Pleskacz
The study aimed to assess the influence of post-
pulmonary barotrauma lesions on the heart muscle and
the importance of hyperbaric treatment on exacerbating
such lesions in the heart. The hearts of 35 rabbits were
used in the study. In animals of the experimental group,
pulmonary barotrauma was induced in the pressure
chamber using the proprietary method described in
previous publications.
Authors: M Hobbs & W. Kneller
Previous research has demonstrated that nitrogen
narcosis causes decrements in memory performance, but
the precise aspect of memory impairment is not clear in
the literature. Objective: The present research investigated
the effect of narcosis on free recall and recognition
memory by applying signal detection theory (SDT) to the
analysis of the recognition data.
Authors:
Brandon W. Lewis, Sonika Patial , and Yogesh Saini
The primary purpose of pulmonary ventilation is to supply
oxygen for sustained aerobic respiration in multicellular
organisms. However, abiotic insults and airborne
pathogens present in the environment are occasionally
introduced into the airspaces during inhalation, which
could be detrimental to the structural integrity and
functioning of the respiratory system.Defective mucociliary
clearance (MCC) is often associated with airway
mucoobstruction, increased occurrence of respiratory
infections, and progressive decrease in lung function in
mucoobstructive lung diseases.
Author: Ran Arieli
This paper is a response from Doctor Ran Arieli regarding
a critic expresse by David Doolette (US Navy) regarding
his assertion that nanobubbles formed on a hydrophobic
surface are the source of decompression bubbles.
Authors: Ashish Tawar, P. Gokulakrishnan
This review article is of interest to the doctors who face
the dilemma of treating the rare syndrome of DCI that
could present in the clinical spectrum ranging from
itching and minor pain to severe neurological symptoms
or other systemic pathology. The first aid lies in the
administration of 100% oxygen, and definitive treatment is
therapeutic recompression. With appropriate and
adequate treatment, recovery is complete, but some
severe cases may have lifelong residual deficits, even after
extended and multiple recompressions.
Authors:
Erik Hoencamp, Thijs TCF van Dongen , Pieter-Jan AM van
Ooij , Thijs T Wingelaar, Mees L Vervelde, Dave AA Koch,
Rob A van Hulst, Rigo Hoencamp
This paper was a systematic review of human and animal
studies of medications in the hyperbaric environment.
Studies were subdivided into those describing a
medication/hyperbaric environment interaction and those
concerned with prevention of diving disorders. Studies
without a relation to diving with compressed air, and
those concerning oxygen toxicity, hyperbaric oxygen
therapy or the treatment of decompression sickness were
excluded.
Authors:
Alice Bliznyuk , Yoram Grossman, & Yevgeny Moskovitz
Divers exposed to pressures above 11 bar develop the
high pressure neurological syndrome (HPNS), manifesting
as central nervous system (CNS) hyperexcitability, motor
disturbances, sensory impairment, and cognitive deficits.
The glutamate-type N-methyl-D-aspartate receptor
(NMDAR) has been implicated in the CNS
hyperexcitability of HPNS. NMDARs containing different
subunits exhibited varying degrees of increased and
decreased current at high pressure. The mechanisms
underlying this phenomenon remain unclear.
Authors:
Alice Bliznyuk, Hava Golan, & Yoram Grossman
Professional divers who are exposed to high pressure (HP)
above 1.1 MPa suffer from high pressure neurological
syndrome (HPNS), which is characterized by reversible
CNS hyperexcitability and cognitive and motor deficits.
HPNS remains the final major constraints on deep diving
at HP. Prolonged and repetitive exposure to HP during
deep sea saturation dives may result in permanent
memory and motor impairment. Previous studies revealed
that CNS hyperexcitability associated with HPNS is largely
induced by N-methyl-D-aspartate receptors (NMDARs).
NMDARs that contain the GluN2A subunit are the only
ones that show a large current increase at He HP.
Author:
Simin Berenji Ardestani, Costantino Balestra, Elena V.
Bouzinova, Øyvind Loennechen, & Michael Pedersen
Symptoms of high-pressure neurological syndrome
(HPNS) might appear at depths deeper than 150 meter
sea water (msw),due to rapid increase in pressure on the
central nervous system during compression. The aim of
this study was to first operate a new computerized tool,
designed to monitor divers’ wellbeing and cognitive
function, and to record the results. The second aim was
to evaluate the feasibility and validity of the Physiopad
software and HPNS questionnaires as a new tool for
monitoring divers wellbeing in an operational setting,
including visualization and presentation of results.
Authors: Dirk Mayer, Katja Bettina Ferenz
The question of deep and shallow decompression stops is
interesting and fraught with controversy in diving circles
and operations, training, exploration and scientific
endeavors. Plus, fraught with some misunderstanding
which is understandable as the issues are complex. We
accordingly detail a short history of deep and shallow
stops, physical aspects, staging differences, diving tests,
models, data correlations, data banks, diver statistics and
DCS outcomes for diving amplification. Pros and cons of
deep stop and shallow stop staging are presented.
Misinformation is corrected. Training Agency Standards
regarding deep and shallow stops are included.
Authors: B. R. Wienke, and T. R. O’ Leary
The question of deep and shallow decompression stops is
interesting and fraught with controversy in diving circles
and operations, training, exploration and scientific
endeavors. Plus, fraught with some misunderstanding
which is understandable as the issues are complex. We
accordingly detail a short history of deep and shallow
stops, physical aspects, staging differences, diving tests,
models, data correlations, data banks, diver statistics and
DCS outcomes for diving amplification. Pros and cons of
deep stop and shallow stop staging are presented.
Misinformation is corrected. Training Agency Standards
regarding deep and shallow stops are included.
Authors:
Denis A. Tolstun, Anna Knyazer, Tetiana V. Tushynska,
Tatyana A. Dubiley, Vladislav V. Bezrukov, Vadim E.
Fraifeld, Khachik K. Muradian
The authors hypothesised that a hypoxic-hypercapnic
environment (HHE) could induce metabolic suppression
and associated benefits for health and longevity, as
observed in the naked-mole rat (NMR).
We developed a model of self-produced HHE, similar to
the natural habitat of NMRs, which is simple, reliable,
natural, and does not require external sources of gases or
complex technical equipment.
Author: David J Doolette
This is a brief document from Doctor Doolette that
provides an update on the current knowledge regarding
gas micronuclei, which are minuscule gas-filled voids
suspended in liquids that are considered the starting point
for bubble formation.
Authors: Tobias Cibis, Alistair McEwan, Arne Sieber,
Bjoern Eskofier, Karl Friedl, & Michael Bennett
This review discusses diving physiology and related
conditions, identifying key physiological parameters for
monitoring.
The authors explored technological solutions, particularly
wearable monitoring technologies, and assessed their
suitability for underwater use. They also reviewed current
safety devices, such as dive computers, focusing on their
decompression models and algorithms. This review
highlights the importance of biomedical monitoring in
diving and encourages further research and development
to improve safety.
Authors: Muhammad Imran Qadir, Hira Naeem Qureshi
The presence of substances such as glucose, protein, and
other molecules in urine is referred to as urine specific
gravity. Typically, urine specific gravity ranges from 1.010
to 1.030. Many people resort to stress eating due to
increased stress and tension in their lives. This habit can
lead to obesity and other significant health issues.
A study involving 80 students who underwent a urinalysis
test to measure urine specific gravity found no correlation
between urine specific gravity levels and stress eating.
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Author: Justin M. Hintze, Lina Geyer, Conall W. Fitzgerald,
Cristina Simoes Franklin, Fergal Glynn, Laura Viani,
Peter Walshe
The paper provides recommendations based on a study of
complications associated with SCUBA diving in patients
with cochlear implants. This study describes a retrospective
case series and literature review, highlighting specific cases
and the difficulties SCUBA divers face with cochlear
implants. The authors aim to raise awareness about
potential risks and suggest caution and adherence to
safety limits for such patients.
Authors: Geoffrey E. Ciarlone, Christopher M. Hinojo,
Nicole M. Stavitzski, Jay B. Dean
This document comprehensively reviews the central
nervous system oxygen toxicity (CNS-OT) associated with
hyperbaric oxygen (HBO2) therapy and underwater
activities. It explains the limitations and risks of HBO2
exposure due to CNS-OT, the symptoms and progression
of CNS-OT, the variability in the latent period of safe
oxygen breathing, summarizes current understanding of
the pathophysiology of CNS-OT, highlights conditions that
accelerate seizure onset, and the current strategies and
research for mitigating CNS-OT to enable safer and longer
HBO2 exposures.
Authors:
Anne-Virginie Desruelle, Pierre Louge Simone Richard
Jean-Eric Blatteau, Sandrine Gaillard, Sébastien De Maistre,
Hélène David, Jean-Jacques Risso, and Nicolas Vallée
This study investigates the effects of minocycline, an
antibiotic, on decompression sickness (DCS) in mice. It
explores the potential of minocycline to modulate blood
parameters and its impact on the symptoms of DCS.
Additionally, it evaluates the use of infrared (IR) imaging as
a diagnostic tool to differentiate between healthy and
DCS-affected mice by detecting hypothermia and other
temperature-related changes.
Authors: Kaitlin N. Allen, & José Pablo Vázquez-Medina
This study reviews the current knowledge on how marine
mammals manage to suppress inflammation and cope
with oxidant generation resulting from
ischemia/reperfusion events that occur during their long-
duration dives. It highlights the contrast between the
detrimental effects of ischemia/reperfusion in humans and
the apparent lack of such effects in diving mammals,
suggesting a focus on the biological strategies these
animals employ to mitigate potential damage.
Authors: Sheeba Santhosh, A Vimala Juliet, G Hari
Krishnan
This document discusses the importance of electrode
selection and placement in medical diagnostics,
particularly when measuring electrical signals in the
human body, such as ECG, EEG, and EMG. It emphasizes
how the type and positioning of electrodes are crucial for
accurate bioimpedance measurements used in the
diagnosis of various disorders. Based on these factors, it
also analyzes different electrode systems used for cardiac
bioimpedance monitoring.
