Scientific papers 2021 - Part A
Click here
Click on the octopus
to return to the top
of the page
Authors:
Thijs T. Wingelaa, Leonie Bakker, Frank J. Nap, Pieter-Jan
A. M. van Ooij, Edwin L. Endert, and Rob A. van Hulst.
Intrapulmonary pathology, such as bullae or blebs, can
cause pulmonary barotrauma when diving. Many diving
courses require chest X-rays (CXR) or high-resolution
computed tomography (HRCT) to exclude asymptomatic
healthy individuals with these lesions. The ability of routine
CXRs and HRCT to assess fitness to dive has never been
evaluated.
Authors: Wei-Shih Tseng, Nian-Sheng Tzeng, Kung-Hung
Lin, Nan-Chieh Huang, Man-Yuan Huang, and
Bor-Hwang Kang
Divers with a history of decompression sickness may be at
high risk for sleep problems. However, limited studies have
investigated the relationship between diving exposure and
sleep problems of occupational divers. This study
investigated the association between diving exposure and
sleep quality and quantity among male occupational
divers in southern Taiwan.
Authors:
Patrice Jissendi-Tchofo, Yassin Jdaoudi, Peter Germonpré,
Danilo Cialoni, Andrea Brizzolari, Patrick Musimu,
Costantino Balestra.
This study hypothesizes that Blood Oxygen Level
Dependent signal variations express the functional
adaptive diving response under prolonged apnea at rest.
That is a preliminary report whose results are promising for
large series of investigations.
Authors: David Q. Le, Paul A. Dayton, Frauke Tillmans,
John J. Freiberger, Richard E. Moon, Petar
Denoble, Virginie Papadopoulou
The purpose of this review is to provide a technical
overview of the use of ultrasound in decompression
research, particularly Doppler ultrasound and brightness
(B)-mode ultrasound. Furthermore, the authors discuss
the strengths and limitations of these technologies. and
how new advancements are improving our ability to
understand bubble behavior post-decompression.
Authors: Andreas Fichtner, Benedikt Brunner, Thomas
Pohl, Thomas Grab, Tobias Fieback, Thea Koch
This study evaluated 342 open-circuit air dives using
echocardiography and the Eftedal-Brubakk bubble-grade
classification system. Post-dive cardiac bubbles were
observed in 47% of the dives, which were found to be
correlated with dive parameters and age.
The authors concluded that simple dives and individual
parameters allow for a reasonable estimation of medium
to high bubble grades, providing information on
decompression stress after ascent. Based on this
conclusion, the authors proposed a formula for estimating
bubble grades.
Authors: Gianpiero Italiano, Laura Fusini, Valentina
Mantegazza, Gloria Tamborini, Manuela Muratori,
Sarah Ghulam Ali, Marco Penso, Anna Garlaschè,
Paola Gripari and Mauro Pepi
Cardiovascular imaging is advancing quickly, with
technologies such as three-dimensional echocardiography
improving heart structure analysis. New software such as
transillumination offers detailed descriptions of valve
lesions, crucial for severity grading. In addition, machine
learning algorithms now provide fast and accurate
chamber quantification, essential for assessing left
ventricular function and guiding clinical decisions. This
review highlights these innovations in echocardiography,
offering deeper insights into heart diseases.
Author: Jan Risberg
This systematic review presents the results of a literature
search for studies reporting the incidence of DCS, venous
gas embolism (VGE), or subjective health reports after
multi-day hyperbaric exposure in humans and
experimental animals. The results suggest that multi-day
hyperbaric exposure is likely to have an acclimatizing effect
and protect against DCS. However, the mechanisms
causing acclimatization, the extent of protection, and the
optimal procedure for acclimatization have not been
adequately investigated.
Author: arosław Krzyzak, Krzysztof Korzeniewski
New and active divers, whether recreational or
professional, are required to have a fitness to dive
certificate. This certificate ensures that there are no
medical reasons preventing someone from diving.
Evaluating health and approving diving under hyperbaric
conditions is often the responsibility of a diving instructor,
underwater work manager, or physician. Legal standards
for these certificates vary between recreational and
occupational divers.
Authors: Danilo Cialoni, Andrea Brizzolari, Michele Samaja,
Gerardo Bosco, Matteo Paganini, Massimo Pieri,
Valentina Lancellotti, & Alessandro Marroni
This study investigates the physiological responses of
expert breath-hold divers to repetitive dives. It specifically
measures changes in nitrate and nitrite (NOx)
concentration, total antioxidant capacity (TAC), and lipid
peroxidation (TBARS) in blood plasma before, during, and
after the dives. The results indicate significant changes in
NOx and TAC levels at the bottom of the dive, which
return to normal shortly after surfacing, while TBARS levels
remain unchanged throughout the protocol.
Authors: Kirsi O. Lorentz, Bianca Casa
This study assesses the prevalence of External Auditory
Exostoses (EAEs) in a Chalcolithic skeletal assemblage from
Souskiou-Laona, southwestern Cyprus. It aims to
understand human-environment interactions, activity
patterns, and behavioral differences between sexes based
on the presence of EAEs linked to repetitive aquatic
activities. The findings suggest that both males and
females participated in these activities, with varying
prevalence rates, and these differences may reflect
increasing specialization and social complexity during the
Chalcolithic period.
Authors: Cassondra L. Williams, and Paul J. Ponganis
This document provides a comprehensive review of the
advancements and current state of research in the field of
diving physiology of marine mammals and birds. It outlines
the historical context, key developments, and
technological advancements that have facilitated field
studies, particularly through biologging. It also highlights
significant research findings in areas such as heart rate,
blood flow, body temperature, and oxygen store
management during diving. Additionally, it discusses the
challenges and future directions for research in this field.
Authors: Krzysztof Dziewiatowski, Romuald Olszanski, Piotr
Siermontowski
This document describes the case of a Polish Navy Dive
Medical Officer who experienced decompression illness
(DCI) symptoms 20 years ago and was later diagnosed
with a right-to-left shunt (RLS) across a patent foramen
ovale (PFO), suggesting that this undiagnosed condition
may have contributed to the initial DCI incident. The
authors argue for the development of standards for initial
PFO screening in certain groups of divers to enhance
diving safety, recommending the use of contrast-
enhanced transcranial Doppler ultrasound for RLS
screening and the use of multi-compartment chambers for
recompression treatment.
07 - Predicting the effect of decompression sickness on survival
following submarine tower escape
- Published by Emerald Insight
Authors: Geoff A.M. Loveman, & Joel J.E. Edney
The purpose of the present study was the development of
a methodology for translating predicted rates of
decompression sickness (DCS), following tower escape
from a sunken submarine, into
predicted probability of survival, a more useful statistic for
making operational decisions.
According to the authors’ knowledge, this study
represents the first attempt to quantify the effect of
different DCS symptoms on the probability of survival in
submarine tower escape.
02 - Dopamine-dependent biphasic behaviour under ‘deep diving’
conditions in Caenorhabditis elegans.
- Published by The Royal Society
Authors: Inbar Kirshenboim, Ben Aviner, Eyal Itskovits,
Alon Zaslave, and Limor Broday
Underwater divers face neurological risks from increased
pressure, particularly due to the effects of inert gases like
helium and nitrogen, leading to nitrogen narcosis. This
study explored the behavior of the soil nematode
Caenorhabditis elegans under scuba diving conditions. By
examining wild-type and dopamine pathway mutant
nematodes at various pressures and gas compositions,
the research found that speed changes in response to
pressure depended on dopamine levels. Dopamine-
deficient mutants did not show this response, indicating
the role of dopamine in high-pressure reactions. C.
elegans is identified as a valuable model for studying
nitrogen toxicity mechanisms.
05 - Case Studies in Physiology: Breath-hold diving beyond 100
meters - cardiopulmonary responses in world-champion divers
- Published by American Physiological Society
Author: Alexander Patrician, Christopher Gasho, Boris
Spajic, Hannah G. Caldwell, Darija Bakovic -
Kramaric, Otto Barak, Ivan Drvis , Zeljko Dujic,
and Philip N. Ainslie
This case study examines two world-champion breath-
hold divers' physiological responses to deep dives of 102
m and 117 m. The divers showed impressive
management of stress during extreme hydrostatic
pressures. Pulmonary function assessments revealed
impaired gas exchange efficiency immediately post-dive,
but recovery occurred within hours. Both divers
experienced transient issues like hemoptysis and nitrogen
narcosis, highlighting their extraordinary apneic
performance under severe physiological conditions.
13 - Rapid ping-pong eye deviation following a recovery from
carbon dioxide narcosis
- Published by BMJ Journals.
Author: Shuichiro Neshige, Ohno Narumi, Shiro Aoki,
Hirofumi Maruyama
A 70-year-old woman with a history of panic disorder
was admitted to the emergency room due to carbon
dioxide narcosis due to atelectasis after lung cancer
lobectomy. After mechanical ventilation, she improved
consciousness and reduced responsiveness to the
environment. Neurological tests showed normal motor
function but she did not move voluntarily. Despite
breathing, she remained ventilator-dependent. The only
neurological abnormality was rapid 'ping-pong' eye
deviations, which disappeared when she was relaxed.
She was diagnosed with catatonia and functional
saccadic oculomotor disturbance
Authors: Pedro Valente Aguiar, Bruno Carvalho, Pedro
Monteiro, Paulo Linhares, Óscar amacho,
Rui Vaz
Resistant CNS infections—postoperative brain/spine
infections and spontaneous rhino-orbital-cerebral
mucormycosis (ROCM)—pose significant therapeutic
challenges. This retrospective case series (2010–2018)
evaluated hyperbaric oxygen therapy (HBOT) as
adjunctive treatment in seven refractory cases. All had
failed prior management—averaging four surgeries and
five months of antimicrobials. After HBOT, six achieved
infection resolution without further surgery; one ROCM
patient discontinued HBOT after three sessions due to
intolerance. Three patients ceased antimicrobials entirely;
four continued prophylactic therapy.
Authors: Nazim Ata, Erkan Karaca
Hypoxia exposure training, mandatory for aircrew and
generally safe, carries a risk of decompression sickness
(DCS), which typically affects individuals singly. This report
describes a rare cluster of three simultaneous DCS cases,
exceeding the usual incidence rate, and investigates it
using an epidemic DCS framework focusing on time,
place, population, and environment. The cluster was
classified as individual-based, highlighting environmental
factors. Equipment analysis identified perforations in the
oro-nasal oxygen masks used during training as the likely
cause for two cases. This finding led to replacement of
damaged equipment and modification of training
procedures to prevent recurrence.
Authors: Charles P Azzopardi, Kurt Magri, Alex Borg, Jake
Schembri, Jonathan Sammut
This case involves a diver experiencing decompression
sickness (DCS), specifically cutis marmorata, which is linked
to persistent foramen ovale (PFO) as a risk factor. Initial
transthoracic echocardiography with antecubital agitated
saline bubbles (ASBs) showed no shunt due to a large
Eustachian valve, but intra-femoral ASB injection revealed
a large PFO with spontaneous shunting. The report
stresses using proper echocardiography techniques
before employing intra-femoral injections to overcome the
Eustachian valve's hemodynamic effects.
Authors: William Brampton, Martin DJ Sayer
A diver with a moderate-to-large unclosed patent foramen
ovale (PFO) and a prior neuro-spinal decompression
sickness (DCS) episode with relapse returned to diving 15
months later, following the conservative 2015 PFO-and-
diving guidelines. After a single cautious dive, an
accidental post-surfacing Valsalva maneuver likely
triggered mild but recurrent DCS symptoms mirroring her
prior episode. She required multiple hyperbaric oxygen
treatments and had residual deficits at discharge. Despite
adherence to current recommendations, this case
suggests that some divers with unclosed PFO and a
history of serious DCS may remain at unacceptable
risk—even with strict conservative diving practices.
Authors: Derek Covington, Chris Giordano
This commentary discusses a fatal case of pulmonary
barotrauma and cerebral arterial gas embolism in a
breath-hold diver who inhaled from a compressed gas
cylinder at 10 msw and ascended without exhaling. While
such injuries are rare in traditional breath-hold diving, they
are emerging among 'technical freedivers', a growing
group using compressed gas at depth to extend dive
depth and duration. Instructors emphasize exhaling
during ascent to prevent barotrauma, often aided by
safety divers. Pioneers like Kirk Krack use this technique
alongside other tools (e.g., propulsion vehicles) to access
previously scuba-only environments, as demonstrated in
dives at Truk Lagoon.
Author: F Michael Davis
A severely injured patient, intubated post-accident, was
inadvertently administered nitrous oxide (N2O) instead of
oxygen (O2) during anesthesia. After rapid correction with
100% O2, he experienced cyanosis, tachypnea, and a
grand mal convulsion within seconds, controlled by
thiopentone. The cause of the convulsion likely stemmed
from either acute hypoxic hypoxia or oxygen toxicity
following reoxygenation. The incident was traced to an
unfamiliar anesthetic machine configuration, where the
N2O rotameter was positioned oppositely to standard
setups. The case underscores the risks of oxygen toxicity,
particularly when hypoxia disrupts cerebral vascular
regulation.
Authors: Björn Edvinsson, Ulf Thilén, Niels Erik Nielsen,
Christina Christersson, Mikael Dellborg, Peter
Eriksson, Joanna Hlebowicz
Interatrial communication, specifically a patent foramen
ovale (PFO), is linked to an elevated risk of decompression
sickness (DCS) in scuba divers. While PFO closure is
hypothesized to reduce this risk, supporting clinical
evidence remains limited. This document discusses a study
of nine Swedish divers with a history of DCS and PFO
closure, who performed 6,835 dives pre-closure and 4,708
post-closure. Most reported DCS symptoms before closure
(7 mild, 10 serious), but only one diver experienced serious
DCS post-closure, attributed to a provocative dive profile.
The findings suggest potential benefits of PFO closure,
though evidence is constrained by a small sample size.
Authors: Michal Hájek, Dittmar Chmelar, Jakub Tlapák,
František Novomeský, Veronika Rybárová,
Miloslav Klugar
Chronic pain can arise from various conditions, including
neuropathic pain, complex regional pain syndrome
(CRPS), and fibromyalgia. Effective treatments with minimal
side effects are needed. One option is hyperbaric oxygen
treatment (HBOT). A case study details a patient who
experienced two events of recurrent post-traumatic CRPS
in both lower and upper limbs, managing pain with
pharmacological treatment and HBOT, leading to
significant improvement. Patients with a history of CRPS
are advised they may be at risk for developing secondary
CRPS after surgery or trauma.
Authors: Morten Hedetoft, Michael H Bennett, Ole
Hyldegaard
Standard treatments for necrotising soft-tissue infections
(NSTI) include surgery, antibiotics, and intensive care.
While hyperbaric oxygen therapy (HBOT) has been used
for decades as an adjunct, its efficacy remained unclear.
This systematic review (PROSPERO-registered) analyzed
clinical studies comparing HBOT and non-HBOT patients.
Among 48,744 NSTI patients, in-hospital mortality was
9.8%, with HBOT associated with significantly lower odds
of death (OR 0.44, 95% CI 0.33–0.58). HBOT also trended
toward reducing major amputations (OR 0.60, 95% CI
0.28–1.28), though oxygen dosing was inconsistently
reported.
Authors: Prashant Komdeur, Thijs T Wingelaar, Rob A van
Hulst
A study analyzed the health conditions of Dutch diving
instructors in light of demographic aging. An online
survey yielded 497 responses (27% response rate), with an
average age of 57.3 years, mostly male. While 46% had
no current health issues, the most reported conditions
were hypertension, hay fever, and equalization problems.
Many instructors had past conditions like equalization
issues and joint pain. Medication use was notable, with
59% taking non-prescription and 49% prescription
medications. Additionally, 66% of male and 38% of female
instructors were classified as overweight, with all
instructors reporting cardiovascular disease being
overweight.
Authors: Jacek Kot, Ewa Lenkiewicz, Edward Lizak, Piotr
Góralczyk, Urszula Chreptowicz
A 51-year-old hyperbaric physician experienced spinal
decompression sickness (DCS) shortly after a routine 70-
minute HBOT session (2.5 ATA) as an inside attendant in a
multiplace chamber, despite being an experienced diver
and within no-decompression limits. Prompt
recompression with US Navy Treatment Table 6 led to
rapid resolution of neurological symptoms. He resumed
work after four weeks of no hyperbaric exposure, and
follow-up echocardiography 18 months later showed no
patent foramen ovale. This case underscores that internal
hyperbaric attendants face significant occupational DCS
risk, even during standard protocols, amplified by age,
fatigue, dehydration, etc.
Author: Ajit C Kulkarni
Multipurpose Support Vessels with advanced diving
capabilities are used in the offshore oil industry for subsea
pipeline inspection, maintenance, and repair. Despite
stringent safety protocols and regulatory oversight
developed after past fatal diving accidents, incidents,
especially those involving divers in water, remain a serious,
often fatal, risk. A key hazard is hydrogen sulphide (H2S),
or 'sour gas', produced by anaerobic bacteria acting on
sulphate-rich organic matter. Highly toxic, H2S
contaminates 'sour crude' transported via pipelines. Divers
responding to leaks frequently contact this crude, coating
their hot water suits and umbilicals with H2S-laden fluid,
posing a contamination risk to the diving bell
environment, as evidenced by a reported fatality.
Authors: Michelle L Lim, Soo J Kim, Meng K Tan, Kim H
Lim, Hooi G See
The document describes managing a critically ill patient
with severe carbon monoxide poisoning who was also
suspected of having COVID-19, requiring emergency
hyperbaric oxygen treatment (HBOT). Key strategies
included minimizing infection risk through strict protocols:
aerosol-generating procedures (e.g., endotracheal tube
manipulation) should be performed in negative pressure
rooms. Intubated patients pose lower risk than non-
intubated, coughing patients. Successful HBOT
administration for an intubated COVID-19 suspect requires
strict infection control, contact precautions, optimized
hospital workflows, and teamwork.
Authors: John Lippmann, Chris Lawrence, Michael Davis
This study examines snorkelling and breath-hold diving
fatalities in New Zealand from 2007 to 2016. Researchers
analysed data from multiple coronial and diving safety
databases to identify risk factors. Of 38 deaths, 29 involved
seafood gathering and 6 were recreational snorkellers.
Two-thirds of victims were diving alone without
supervision. Key risk factors included: 28 victims being
overweight or obese, 19 being Maori, and 30 having pre-
existing health conditions, predominantly cardiac issues
(18 cases). Other contributing factors were diabetes,
epilepsy, asthma, and substance use (cannabis/alcohol in
7 cases). Five deaths resulted from apnoeic hypoxia. The
findings highlight the importance of supervision, health
screening, and awareness of diving risks.
Authors: Louise MacInnes, Carol Baines, Alexandra Bishop,
Karen Ford
This study examines patients' knowledge and experiences
of hyperbaric oxygen treatment (HBOT) through surveys
and interviews. Prior to HBOT, 52% of participants were
aware of its use for divers, with 60% of those also knowing
it treats non-divers; only one-third sought additional
information post-referral. Anxiety decreased significantly
after treatment. Key themes from interviews included
personal anxiety, initial unfamiliarity, enjoyment of the
'diver' experience, and the challenges of HBOT.
Authors: Stephanie M Price, Will D Price, Mickaila J
Johnston
This document describes the unusual case of a civilian
diver who developed pneumomediastinum with
significant respiratory symptoms. Standard treatment with
normobaric 100% oxygen proved ineffective. After ruling
out pneumothorax, hyperbaric oxygen therapy
successfully relieved the patient's symptoms,
demonstrating a novel treatment approach for this
complication.
Authors: Marcello Sanzi, Alberto Aiolfi, Jacopo Nicolò
Marin, Abd El Hakim Darawsh, Davide Bona
This report details the use of hyperbaric oxygen treatment
(HBOT) to manage colorectal anastomosis ischaemia after
surgery. A 47-year-old man developed an anastomotic
leak with ischaemia 17 days following laparoscopic low
anterior resection for rectal adenocarcinoma. He
underwent 11 HBOT sessions over three weeks and was
monitored endoscopically and radiologically for two
months. Healing of the anastomosis was confirmed at two
months, allowing ileostomy closure. The patient retained
satisfactory anal function without incontinence or sepsis.
Authors: Susannah Sherlock, Sharon Kelly, Michael H
Bennett
This study assessed the impact of the 2014 UHMS revision,
which approved idiopathic sudden sensorineural hearing
loss (ISSHL) as an HBOT indication, on referral patterns in
Australia and New Zealand. Analyzing 319 referrals across
two periods, it found a significant rise in the share of ISSHL
patients treated with HBOT. ISSHL accounted for 3.2% of
HBOT indications in the earlier period and 12.1% in the
later period. A single hyperbaric facility contributed most
ISSHL cases in both periods and showed a notable uptick
after the guideline change. Overall, three of seven facilities
experienced a significant increase in ISSHL referrals
following the revision.
Authors: Nicole E Spruijt, Lisette T Hoekstra, Johan
Wilmink, Maarten M Hoogbergen
This study investigated the effectiveness of hyperbaric
oxygen treatment (HBOT) for mastectomy flap ischemia.
Analyzing 50 cases, researchers found that while 34% of
surface area ischemia scores improved with HBOT, depth
scores worsened in 42% (both P < 0.01). More severe
necrosis, indicated by higher SKIN scores, correlated with
an increased need for re-operation. Ultimately, 58% of
breasts recovered without further surgery. Preoperative
radiotherapy and postoperative infection were identified
as significant risk factors for requiring re-operation.
Authors: Derya Ümit Talas, Orhan Beger, Ülkü
Çömelekoglu, Salim Çakır, Pourya Taghipour,
Yusuf Vayisoglu
This cadaveric study investigated the rupture pressure of
the tympanic membrane (TM) to assess its tensile strength
for otological purposes. Twenty ears from 10 fresh frozen
cadaveric heads were examined. Tensile strength was
evaluated by measuring bursting pressure, while
membrane and perforation dimensions were assessed
using digital imaging. The mean bursting pressure was
97.71 kPa, with mean TM area of 57.46 mm². No
significant differences were found between genders or
ear sides. Importantly, bursting pressure showed no
correlation with TM size or perforation dimensions.
