Scientific papers 2019 - Part B
Authors: Rongjia Zhang, Hongda Bi, Ning Zhang, Ting
Zhang, Zhouheng Ye, Xuejun Sun, Yongchao
Yu, Anatol Manaenko, & Ling Zhang.
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.
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
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:
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: 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:
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.
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:
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.
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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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.
Authors:
Kaighley D. Brett, Nathan Z. nugent, Noelle K. fraser,
Veena M. Bhopale, Ming Yang, & Stephen R. thom
This study presents scientific research findings on the
production of blood-borne microparticles (MPs) and
interleukin (IL)-1beta in response to high pressure in
humans and investigates whether these responses occur
due to exposure to high pressure or the process of
decompression, using data from experiments conducted
in hyperbaric chambers. The research aims to convey the
results, which show that MPs and IL-1B levels increase
during high-pressure exposure and persist after
decompression, suggesting potential health implications
and the need for further studies
Authors: Amalie Ustrup, Signe Knag Pedersen, Charlotte
Suppli Ulrik
This paper introduces a study that developed and tested a
clinical algorithm to assess the fitness of individuals with
asthma for scuba diving to determine if individuals with
asthma could be safely classified as having no medical
contraindications to scuba diving after undergoing
specific tests and potential asthma therapy adjustments. It
suggests that while the algorithm shows promise, further
studies are necessary to confirm its safety and
effectiveness in real-world scuba diving scenarios.
Author: Kevin M. Pitt, Jonathan S. Brumberg, Jeremy D.
Burnison, Jyutika Mehta, Juhi Kidwai
The purpose of this document is to inform about the use
of brain-computer interface (BCI) techniques, particularly
in the context of augmentative and alternative
communication (AAC) for individuals with severe physical
impairments, to clarify how electroencephalography
(EEG) records brain signals related to BCI, what specific
signals are targeted for BCI control, and why these signals
are chosen. Also, it provides a tutorial developed by a
multidisciplinary team to enhance understanding of BCI-
AAC-related signals.
Authors:
Marguerite St Leger Dowse, Ben Whalley, Matthew K
Waterman, Robert M Conway, Gary R Smerdon
The survey discussed in this paper was conducted to
investigate the prevalence of mental health (MH) issues
and the use of prescription medications among sports
divers in the United Kingdom to highlight the rate of non-
compliance with current medical guidelines among divers
with depression and anxiety and to consider the positive
effects of scuba diving on mental health. The survey also
suggests that changes in diver training and guidelines
may be needed to encourage accurate reporting and to
develop evidence-based protocols that consider both the
risks and potential mental health benefits of diving.
Author: Ran Arieli
This document presents findings related to the behavior
of lung surfactant and its role in the formation of
decompression bubbles in blood vessels. It describes an
experiment involving sheep blood vessels and hyperbaric
pressure, and it aims to provide insights into the dynamics
of decompression bubbles, which could be used to
improve models of decompression physiology.
Additionally, it discusses the implications of bubble size in
the venous circulation.
21- Bubble Solution Description by Non-Extensive Thermodynamics:
Pressure Effect
- Published by
the Universite de Bretagne Occidentale
Author: Pierre Letellier, Mireille Turmine
This study explains that nanobubble solutions are not
just a mix of solutions and bubbles but are
"supersaturated solutions" with gas in two forms. Gibbs'
thermodynamics cannot describe their behavior.
Nonextensive thermodynamics helps explain their
properties, including counter-intuitive effects like
increased bubble size with increased pressure. The
proposed relationships offer a new approach to
understanding these solutions and their unique
characteristics.
28 - A new form of admissible pressure for Haldanian
decompression models
- Published by Computers in Biology and Medicine - Science Direct.
Author: Alexis Blasselle, Michael Theron, Bernard
Gardette, Emmanuel Dugrenot
In this article, we propose a new form of admissible
pressure in the Haldanian framework. We study the
surjectivity of the Gradient Factors and a specific case. This
case leads to a decompression strategy focused on ascent
rate, suggested by COMEX using a physiologically
relevant method. This strategy combines the COMEX
approach with the Haldanian method.
Author: Barbara E. Shykoff, Rees L. Lee
Effects of breathing gas with high oxygen levels at sea
level or higher are discussed. High oxygen levels can
cause absorption problems in the lungs and sinuses,
especially if passages are blocked. Symptoms of
pulmonary oxygen toxicity are unlikely in flight. Treatment
for decompression sickness carries risks. Elevated PO2 can
constrict blood vessels and affect blood sugar response.
Healthy lungs do not benefit from increased PO2, and
low humidity in breathing gas can lead to
bronchoconstriction.
27 - Spinal Decompression Sickness in an Experienced Scuba Diver:
A Case Report and Review of Literature
- Published by Sage journals
Authors: Altaf Saadi, Emily A. Ferenczi, and Haatem Reda
Decompression sickness from diving is a rare but
potentially reversible spinal injury. Early treatment with
hyperbaric oxygen improves neurologic outcomes. A 65-
year-old diver experienced thoracic back pain and leg
weakness after a dive, but made partial recovery after
extended therapy. Diagnosis should be based on clinical
evaluation, not MRI findings.
37 - Oxygen toxycity and diving headache
- Published by the Undersea & Hyperbaric Medical Society (Author-provided)
This document contains letters from doctors Ran Arieli,
who explains that diving headaches are mainly related to
hypercapnia, decompression sickness, primary headache
disorders, and possible diving ascent headache.
It also contains a message from Doctor Susan
Steinemann, who criticizes an article that incorrectly
portrays the University of Hawaii's hyperbaric services as
lacking a 24/7 hyperbaric chamber for critical patients.
38 - Inhibition of NR2B-containing NMDA receptors during nitrogen
narcosis
- Published by Diving and Hyperbaric Medicine.
Authors: Bin Peng, Du-Du Hao, Xia Li, Guo-Hua Wang,
Zong-Yu Guan, Zheng-Lin Jiang
When humans breathe compressed air or nitrogen-
oxygen mixtures at high pressure, they may experience
nitrogen narcosis, which can lead to diving accidents.
However, the exact causes are still not clear. In this study,
mice were exposed to a nitrogen-oxygen mixture under
pressure, and their brain activity and behavior were
analyzed. Results showed that brain activity decreased
significantly during exposure. Furthermore, exposure to
high pressure inhibited the activity of specific receptors in
cultured hippocampal neurons, indicating a potential
mechanism for nitrogen narcosis.
11- Obese mice exposed to psychosocial stress display cardiac and
hippocampal dysfunction associated with local brain-derived
neurotrophic factor depletion
- Published by
EBioMedicine
Authors:
Jacopo Agrimi, Cristina Spalletti, Carlotta Baroni, Gizem
Keceli, Guangshuo Zhu, Angela Caragnano, Marco
Matteucci, Stephen Chelko, Genaro A. Ramirez-Correa,
Djahida Bedja, Valentina Casieri, Nicole Di Lascio, Arianna
Scalco, Antonio Paolo Beltrami, Nazareno Paolocci, Matteo
Caleo, Vincenzo Lionetti
This study investigates how psychosocial stress (PS) affects
cardiac and hippocampal functions in obese mice
induced by a high-fat diet (HFD). Using wild-type (WT)
and cardiac-selective TrkB knockout (cTrkB KO) mice, the
research assesses left ventricular (LV) performance,
behavior, and molecular changes associated with brain-
derived neurotrophic factor (BDNF) signaling.
Authors: Charles Paul Azzopardi, Joseph Caruana, Lyubisa
Matity, Stephen Muscat, WA Jack Meintjes
This 30-year retrospective study (1987-2017) analyzed
437 decompression illness (DCI) cases treated at Malta's
single hyperbaric referral centre, which handles all diving-
related DCI in the country. Results showed a shift in DCI
patterns: musculo-skeletal DCI prevalence declined while
vestibulo-cochlear DCI increased, likely reflecting changes
in local diving practices.
Authors: Diogo A Costa, José S Ganilha, Pedro C Barata,
Francisco G Guerreiro
This 20-year retrospective analysis of 188,335 HBOT
sessions showed that adding a 5-minute air-break
reduced CNS-OT seizures from 3.9 to 1.2 per 10,000
treatments (P<0.0001). Seizures occurred at a median of
57 minutes and after 21 sessions, with higher rates in
acute traumatic peripheral ischaemia and necrotising
fasciitis. The protocol significantly lowers seizure risk;
defining high-risk patient/treatment profiles helps
minimize CNS-OT.
Authors: Lone Forner, Adela Berkowicz, Ebbe Dickmeiss,
Ole Hyldegaard, Erik C Jansen, Anne Fischer
Nielsen
Hyperbaric oxygen therapy (HBO) is used to treat
conditions such as late radiation-induced tissue injury and
may mobilize bone marrow-derived stem/progenitor cells
(SPCs) into the peripheral blood, though the cumulative
effects remain uncertain. This study examined HBO-
induced SPC mobilization (measured via CD34+CD45dim
cells and ALDH activity) in 10 patients undergoing HBO
treatment, with 6 completing 29–30 sessions. Platelet
activation was also assessed. Results showed a minor but
statistically significant increase in CD34+CD45dim cells
after 15 sessions, but no effect after 30 sessions.
Authors: Francisco de Asís Fernández, Fernando
González- Mohino, José M González-Ravé
The study investigated the impact of a maximal dynamic
apnoea on sensory sensitivity (SS) in experienced male
breath-hold divers. Using critical flicker fusion frequency
(CFFF) thresholds to measure SS, the study found that SS
remained unchanged (102% of baseline) after the
apnoea, despite significant decreases in oxygen saturation
(SpO2). A moderate correlation was observed between SS
and swimming speed (r = 0.423) and apnoea time (r = -
0.404). The findings suggest that the duration of hypoxia
during a maximal voluntary apnoea is insufficient to alter
SS.
Authors: Fernando Guillén-Pino, Armando Morera-
Fumero, Manuel Henry-Benítez, Emilio Alonso-
Lasheras, Pedro Abreu-González, Vicente
Medina-Arana
This study reports epidemiology of 130 diving injuries
treated at Canary Islands University Hospital's Hyperbaric
Unit (2008-2017). Most victims were men (71%), 43%
foreign, with 18% uncertified. Only 40% received on-site
first aid, and few got oxygen. Type 1 (43%) and Type 2
(52%) decompression sickness predominated. 94% were
discharged asymptomatic, though one died and one
remained quadriparetic. Just 76% had insurance. Over
half lacked first aid; public health recommendations for
the Canary Islands are made.
Authors: Sylvain Boet, Olivia Cheng-Boivin, Leonardo
Martin, Tomi Hurskainen, Cole Etherington
This systematic review aimed to investigate the impact of
simulation-based education in hyperbaric medicine, but
found no relevant English-language studies. Only one
potentially relevant German paper was identified. The
review concludes that more research is needed to
understand the benefits of simulation-based education for
both practitioners and patient care in hyperbaric
medicine.
Authors: Pasquale Longobardi , Klarida Hoxha, Michael H
Bennett
Delayed wound healing, persisting beyond 4-6 weeks of
treatment, poses significant morbidity and healthcare
costs. Hyperbaric oxygen therapy (HBOT) enhances
oxygen delivery to wounds and is explored here for non-
healing ulcers in rare conditions like vasculitis, calcific
uremic arteriolopathy (CUA), livedoid vasculopathy (LV),
and pyoderma gangrenosum (PG). A review of three case
series and four case reports (63 participants) found limited
evidence suggesting HBOT may accelerate wound
healing by boosting nitric oxide levels and endothelial
progenitor cells, while also alleviating pain.
Authors: James Todd, Mark Edsell
Between 40,000 and 50,000 divers and swimmers suffer
envenomation annually, with Weever fish, Scorpion fish,
and jellyfish as the primary culprits in the Mediterranean,
alongside coral and sea urchins. Most stings cause
localized inflammation, swelling, and pain, while severe
cases may lead to life-threatening complications like shock
or organ damage. Prevention is possible through
buoyancy control, protective gear, and vigilance.
Immediate first aid includes exiting the water, elevating
and cleaning the wound, and soaking in hot water for
pain relief. Severe cases—marked by confusion or heavy
bleeding—require urgent medical attention.
Authors: Denise McCool, Chris Butler, John Evans, Carsten
Aase
A 43-year-old female scuba diver was retrieved and
treated following a rapid ascent and presumed cerebral
arterial gas embolism (CAGE). She subsequently
developed respiratory distress and was found to have
Takotsubo cardiomyopathy, with transient left ventricular
dysfunction, elevated cardiac enzymes, and normal CT
coronary angiography. We believe this to be the first
report of CA
Authors: Michael H Bennett, Cheng FB Hui, Hooi G See,
Kwan L Au-Yeung, Christopher Tan, Stephanie
Watson
A temporary myopic shift is a known complication of
hyperbaric oxygen treatment (HBOT), likely caused by
protein oxidation in the crystalline lens. This study
compared the effect of oxygen delivery via hood versus
oronasal mask on myopic shift over 20 and 30 HBOT
sessions in 120 patients. Results showed a significantly
greater myopic shift with the hood at both 20 sessions (-
0.92D vs -0.52D) and 30 sessions (-1.25D vs -0.63D), with
slower and less complete recovery. The findings support
using an oronasal mask over a hood when feasible.
Authors: Kurtuluri Açiksari, Seracettin Egin, Gülçin Hepgül,
Bengüsu Mirasoglu, Gamze Tanriverdi, Devrim S Kanber,
Sibel Demirci, Halil Dogan, Dogaç N Özüçelik, Akın S
Toklu, Ismail Seçkin, Hakan T Yanar
This study evaluated the effects of hyperbaric oxygen
therapy (HBOT) on intestinal healing in rats following
mesenteric ischaemia/reperfusion (I/R). Thirty-two rats
were assigned to I/R, sham, I/R+HBOT (6h post-
reperfusion), or I/R+HBOT (12h) groups. I/R used a 60-
minute superior mesenteric artery occlusion; HBOT
involved 13 sessions (90 min, 2.5 ATA, 100% O2).
Histopathological scores were worst in I/R-only, improved
with HBOT (superior at 6h), and early HBOT raised
glutathione levels.
Authors: Richard V Lundell, Olli Arola, Jari Suvilehto, Juha
Kuokkanen, Mika Valtonen, Anne K Räisänen-
Sokolowski
This first Finnish study on decompression illness (DCI)
examined 571 hyperbaric oxygen-treated cases
(1999–2018), over 95% of national totals, comparing 200
technical and 371 non-technical divers. Technical diving
(mixed gases, CCR, or planned decompression) has risen,
involving deeper, longer dives in cold or overhead
settings. Technical divers used first-aid 100% oxygen more
frequently and sought care earlier, though symptoms
were similar. Annual cases averaged 29, remaining stable.
Most received USN Treatment Table Six, yielding 82%
asymptomatic outcomes.
Authors: Dror Ofir, Yoav Yanir, Mirit Eynan, Yehuda Arieli
The study assessed the thermal protection of a 2–3 mm
wetsuit during two-hour fin dives in 16–20°C shallow
water on six trained, cold-acclimatised male rebreather
divers. Core temperature dropped by 0.35–0.81°C (no
participant fell below 35°C), while upper body skin
temperature decreased by 5.97–8.41°C. Manual dexterity
declined (~30% longer task completion time, P < 0.05),
but cognitive performance and muscle strength remained
unaffected. The wetsuit provided sufficient thermal
protection for trained, cold-adapted divers in water ≥16°C.
Authors: Thijs T Wingelaar, Edwin L Endert, Rigo
Hoencamp, Peter-Jan AM van Ooij, Rob A van
Hulst
Hearing loss (HL) is prevalent among working adults, and
diving is often considered a risk factor, though long-term
comparative studies are scarce. This 25-year retrospective
study analyzed Royal Netherlands Navy divers with over
15 years of experience, comparing their hearing
thresholds (HT) to ISO 7029:2017 standards. Among 35
divers, significant HT increases were observed in 9 of 16
frequencies, but Z-scores, adjusted for age, showed no
worsening and even better hearing than non-divers in
some cases.
Authors: Nicholas Gant, Hanna van Waart, Edward T
Ashworth, Peter Mesley, Simon J Mitchell
This study compared ExtendAir® cartridge and granular
Sofnolime® scrubbers of equal size in an immersed
O2ptima rebreather under staged and continuous
exercise protocols. Manufacturer claims of twice the
absorptive capacity, less variability, lower work of
breathing, and reduced causticity after flooding lacked
supporting data. Results showed only 0–20% longer
endurance for the cartridge depending on protocol and
CO2 endpoint, with no meaningful differences in
variability, inspiratory-expiratory pressure, or eluted water
pH. Conclusions indicate similar performance overall,
inconsistent with claims of substantial superiority.
Authors: Neil DG Banham, John Lippmann
Cerebral arterial gas embolism (CAGE) is a recognized
scuba diving hazard caused by breath-holding during
ascent. While breath-hold divers with normal lungs are
typically safe, those who breathe compressed gas at
depth face significant risk of pulmonary barotrauma and
CAGE upon surfacing. A 26-year-old breath-hold diver
who used a scuba set at 10 meters depth died from
severe barotrauma and CAGE after ascending. Both
breath-hold and scuba divers, particularly inexperienced
ones, must understand this critical danger.
Authors: Payal S Razdan, Dominique Buteau, Neal W
Pollock
A broad differential diagnosis is crucial but challenging,
especially for conditions like decompression sickness
(DCS), which can mimic other disorders. While hyperbaric
oxygen treatment (HBOT) may improve DCS symptoms, it
can also affect other conditions, such as Löfgren’s
syndrome (LS), a poorly understood sarcoidosis variant
with diverse symptoms. A case is reported where a patient
initially diagnosed with DCS developed LS symptoms after
HBOT.
Authors: Luke R. Johnson, Andrew R. Battle, and Boris
Martinac
NMDAR activation boosts post-synaptic Ca2+
conductance, essential for LTP and memory formation. It
serves as a coincidence detector, opening upon
glutamate/glycine binding and depolarization to relieve
Mg2+ block. Evidence indicates mechanosensitivity via
force-from-lipids and tethering mechanisms, triggered by
membrane stretch or arachidonic acid, potentially
enhancing NMDAR activity to facilitate memory. This
review examines NMDAR roles in nervous system
mechanobiology, mechanisms of mechanosensitive
channels, gain control of opening probability, and
mechanobiology’s implications.
