Scientific papers 1996 - 1998
Next page Next page BUTTON TEXT Previous page Back to the menu 17 - The incidence of decompression sickness arising from commercial offshore air-diving operations in UK sector of the North Sea during 1982/83.
Authors: Doctors Shield & Lee This report is part of the documents that have initiated the implementation of the UK HSE diving bottom time limits that are in force in British waters. Also, they have been adopted by IOGP in the recommended diving practices of the association.
24 - B. W. Hamill, J. E. Hendrix, L. J. Crepeau, J. D. Pelton, M. D. Miley, E. E. Kadlec: Speech intelligibility assessment in a helium environment - The speech intelligibility index.
This document relates experiments where speech Intelligibility was measured with US Navy divers participating in deep saturation dives and a group of non- divers to test different communication systems and their components.
41 - R. Gelfand, C. J. Lambertsen, J. M. Clark, E. Hopkin: Hypoxic ventilatory sensitivity in men is not reduced by prolonged hyperoxia (Predictive Studies V and VI)
The investigations described in this report included observing the development rates of visual, auditory- vestibular, neurological, pulmonary, cardiac, mental performance, and respiratory effects of hyperoxia over the O2 pressure range of 1.5–3.0 ATA. Year of publication: 1998
55 - Yasuhiro Manabe, Kenichi Sakai, Kenichi Kashihara, Toshikiyo Shohmori: Presumed venous infarction in spinal decompression sickness.
This document describes the Magnetic Resonance Imaging (MRI) findings in a patient with spinal decompression sickness. The authors conclude that Magnetic Resonance Imaging (MRI) may facilitate the early diagnosis of spinal decompression sickness. Date of publication: September 1998
15 - Evaluation of decompression sickness risk in saturated air and nitrox dives juged on the basis of changes in haemostasis.. Authors: Romuald Olszanski, Zbigniew Baj, Andrzej Buczynski, Maciej J. Konarski, Ryszard Klos, Stanislaw Skrzynski, and Krzysztof Zeman.
The evaluation of decompression tables and individual sensitivity to decompression disease is primarily based on the detection of symptoms. Thus, not on physiological but pathophysiological criteria. The above situation imposes research into such diagnostic methods that would allow for the evaluation of the decompression system applied. Apart from the "bends" criteria and Doppler monitoring of gas bubbles and blood flow, hemostasis evaluation may well be an indicator that the decompression is correct
22 - Stabilized bubbles in the body: pressure-radius relationships and the limits to stabilization.
Authors: Van Liew, Hugh D., and Soumya Raychaudhuri The authors previously outlined the fundamental principles governing stabilized bubbles' behavior, such as the microbubbles being put forward as ultrasound contrast agents. In this document, their goal is to develop the idea that there are limits to the stabilization and to provide a conceptual framework for comparing bubbles stabilized by different mechanisms.
43 - Role of metabolic gases in bubble formation during hypobaric exposures.
Authors: Philip P Foster, Johnny Conkin, Michael R. Powell, James M. Waligora, & Raj S. Chhikara The authors hypothesize that metabolic gases play a role in the initial explosive growth phase of bubble formation during hypobaric exposures. Models that account for optimal internal tensions of dissolved gases to predict the probability of occurrence of venous gas emboli were statistically fitted to 426 hypobaric exposures from National Aeronautics and Space Administration tests. The presence of venous gas emboli in the pulmonary artery was detected with an ultrasound Doppler detector. The model fit and parameter estimation were done using the statistical method of maximum likelihood.
02 - Statistically Based Decompression Tables IX: Probabilistic Models of the Role of Oxygen in Human Decompression Sickness. Author: Paul K Weathersby
While probabilistic models of human decompression sickness (DCS) have been successful in describing both the level and timing of DCS risk in a wide variety of N2- O2 data, they have failed to account for the observed DCS risk in the currently available collection of dives with significant periods of 100% oxygen breathing. The best model to date, calibrated with over 2300 air and N2-O2 dives, under-predicts the DCS risk of these O2 dives by 60%, whether O2 is breathed during in-water decompression or during surface decompression procedures. This overestimation of the benefit of O2 is due to an exaggerated acceleration of N2 wash-out during O2 breathing.
07 - Statistically Based Decompression Tables X: Probabilistic Models of the Role of Oxygen in Human Decompression Sickness. Author: Paul K Weathersby
Underwater decompression meters or computers sense a diver's changes of depth in real-time and calculate a decompression schedule for the individual diver's exposure. Currently available devices compare calculated nitrogen tissue tensions to a set of stored “safe” constants. No explicit quantitative connection between these rules and the risk of decompression sickness has been established. Well calibrated probabilistic models, even though computationally more intense, can be used to specify decompression procedures tailored to control the risk of decompression sickness...
14 - Detection of circulating bubbles with 2D echocardiography and pulsed doppler
Authors: A. Boussuges, P Ambrosi, G Habib, D Cartran, B. Gardette, JM Sainty Detection of circulating bubbles can be used as an indicator of the safety of a dive and his decompression procedure. Continuous wave Doppler is the more widely used but the analysis of the signals obtained involve a degree of subjectivity. Then, the inter-rater agreement on the grading of intravascular bubble signals can be important and statistics of studies with a few records can be falsified. Others ultrasonic methods for detecting bubbles have been evaluated. Echocardiography can visualised circulating bubbles in right cavities. Transesophageal echocardiography is semi invasive and only used during experimental animal studies.
13 - Recovery time constant in central nervous system O2 toxicity in the rat
Authors: R. Arieli, A. Gutterman The development of oxygen toxicity can be delayed by intermittent periods of normoxia. In this document, doctors Arieli and Gutterman show a procedure for quantifing the recovery during normoxia, so a process that allows calculating the accumulation of oxygen toxicity and its recovery to evaluate central nervous system oxygen toxicity.
42 - Goran E. Nilsson: Respiratory physiology of vertebrates
This document explains the fundamentals of oxygen sensing, uptake, and transport. It also shows examples of extreme respiratory performance, such as diving and high- altitude survival in mammals and birds, air-breathing in fish, and those few vertebrates that can survive without oxygen for several months.
08 - Compressed air work - French tables 1992 - Operational result Authors: (J. C. Le Péchon, P. Barre, J. PBaua'i, F. Ollivier
This document is a presentation of the MT92 for tunneling operations requiring compressed air work, and an analysis of the 1st operations performed with this table.
54 - HeO2 CUMA Repetitive Dive Table Trials - Series 2 and 3 Author: Mark Kessler
This document is a study of tables made in 1998 for the Canadian Underwater Minecountermeasures (MCM) Apparatus (CUMA), a self-contained, semi-closed circuit breathing apparatus in service with the Canadian Forces (CF) for diving on underwater mines to a depth of 81 metres of seawater (msw) using a mixture of helium and oxygen (HeO2). .
23 - EEG and sleep disturbances during dives at 450 msw in helium- nitrogen-oxygen mixture
Authors: C. Rostain, M. C. Gardette-Chauffour, & R. Naquet To study the effects of nitrogen addition to the breathing mixture on sleep disturbances at pressure, two dives were performed in which helium-nitrogen oxygen mixture was used up to 450 m sea water (msw). In total, sleep of 12 professional divers was analyzed (i.e., 184 night records). Sleep was disrupted by compression and by stay at 450 msw: The authors observed an increase in awake periods and in sleep stages I and II and a decrease in stages III and IV and in rapid-eye-movement sleep periods.
01 - Effect of SF6-O2 (80/20) breathing on air bubbles in rat tissues Authors: O. Hyldegaard, J. Madsen
This paper describes studies on the effect of sulfur hexafluoride/oxygen breathing on air bubbles injected into skeletal muscle, rat-tail tendon, the anterior chamber of the eye, and spinal white matter. Decompression- induced nitrogen bubbles in adipose tissue was studied. The results were compared with previous experiments using heliox 80/20.
06 - The effects of wave conditions on dry immersion suit isolation: A comparison between humans and a manikin Author: Michel B. Ducharme, Christopher J. Brooks
This study was designed to investigate the effect of standard wave conditions (0 to 70 cm) on dry immersion suit insulation when tested on humans and a mannequin simultaneously. The objectives of the study were: • To see if the thermal insulation of suits used on a manikin and humans is equally affected by wave motion; • To determine which component of the suit is most affected by wave motion.
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26 - Pulmonary edema of scuba divers
Authors: N.B. Hampson and R.G. Dunford The "cold-induced pulmonary edema" syndrome was first described in 1989, affecting scuba divers in cold European waters. The authors observed six similar cases, five in Puget Sound and one in the Gulf of Mexico, involving four women and two men aged between 24 and 60. This syndrome can occur in both cold and warm waters and is not related to decompression sickness. Medical personnel should be familiar with this condition to manage it effectively.
19 - Doppler-echocardiography study of cardiac function during a 36 atm (3,650 kPa) human dive
Authors: V. Lafay, A. Boussuges, P. Ambiosi, P. Barthelemy, Y Frances, B. Gardette,and Y. Jammes This study focused on the heart's pumping ability and the blood flow during the dive. The findings showed a decrease in heart rate, which led to a reduced overall heart output, while other heart function indicators remained stable. There was no evidence of heart muscle relaxation issues, valve problems, or increased lung artery pressure. The study concluded that this type of echocardiography is a reliable method for monitoring heart function during deep dives, and the dive conditions tested did not significantly alter heart function, aside from the slower heart rate.
28 - Hyperbaric oxygen as a therapy of Bell’s palsy
Authors: G. Racic, P.J. Denoble, N. Srem, L. Bojic and B. Bota This study aimed to evaluate the effectiveness of hyperbaric oxygen (HBO2) versus prednisone in treating 79 Bell’s palsy, a condition that causes temporary facial paralysis on one side of the face. The participants were divided into two groups: 42 received HBO2, and 37 took prednisone. The HBO2 group inhaled 100% oxygen at 2.8 atm abs for 60 minutes, twice daily, for up to 30 sessions or until full recovery, and also took a placebo pill. The prednisone group breathed 7% O2 at the same pressure and schedule and received 450 mg of prednisone over eight days. The findings indicate that HBO2 treatment is more effective than prednisone for treating Bell’s palsy.
33- Effect of dysoxia and moderate air hyperbarism on red-green color sensitivity
Authors: N.A.M. Schellart, M. Pollen, and A. Van Der Kley The study investigated how different levels of oxygen and pressure affect color vision and sensitivity to red and green colors. The findings revealed that normal air pressure with low oxygen enhances red sensitivity by 4%, while high oxygen at the same pressure decreases it by 4%. Hyperbaric oxygen showed a minor reduction in red- green sensitivity, attributed to the counteracting effect of increased carbon dioxide levels. No changes were observed with normal air pressure and oxygen levels
34 - Influence of wet suit wear on anxiety responses to underwater exercise
Authors: K.F. Koltyn and W.P. Morgan The authors examined how wearing a wetsuit affects divers' mental and physical responses. They found that heart rate, air usage, and breathing effort increased in both trials, but these increases were more significant when divers wore wetsuits. Only in the wet suit trial did the divers' core temperature rise significantly. Divers also felt more anxious and aware of their bodies in the wet suit. Interestingly, anxiety levels dropped significantly after swimming without the wet suit. This suggests that wearing a wet suit can make divers feel more anxious, especially when it's warm, and the exercise is intense.
35 - Reversibility in blood-brain barrier, rnicrocirculation, and histology in rat brain after decompression
Authors: A. Nohara and T. Yusa In this study, 90 rats were subjected to high-pressure conditions and then rapidly decompressed to examine the effects on their brain structures. Initially, there were noticeable disruptions, but these issues were largely resolved within 24 hours. However, the problems reappeared about two to three days later. This suggests that the initial recovery might be temporary, and longer- term brain damage could occur due to the stress of decompression.
40 - Decompression Induced Venous Gas Emboli in Sport Diving: Detection with 2D Echocardiography and Pulsed Doppler
Authors: A. Boussuges, D. Carturcin, P. Ambrosi, G. Habib, j. M. Sainty, R. Luccioni This study aimed to determine how pulsed Doppler and 2D echocardiography can detect and measure blood bubbles in divers after decompression. The study concluded that pulsed Doppler was more effective than 2D echocardiography in detecting and measuring blood bubbles in divers after decompression. However, further research is necessary to compare the effectiveness of pulsed and continuous Doppler in detecting these bubbles.
46 - Patent foramen ovale and decompression sickness in sports divers
Authors: P. Gemonpre, P. Dendale, P. Unger, and C. Balestra This study was conducted on sports divers to investigate whether a heart condition known as Patent Foramen Ovale (PFO) could be the cause of unexplained decompression sickness (DCS). Based on the results, PFO is linked to unexplained DCS related to the brain, but not to spinal DCS. The researchers emphasized the need for standardized methods in future studies that use this type of heart scan.
49 - Risk of decompression sickness in shallow no-stop air diving: An analysis of naval safety center data 1990 - 1994,
Authors: E.T. Flynn, E.C. Parker, R. Ball From 1990 to 1994, Navy and Marine Corps divers conducted 163,400 shallow no-decompression dives, ranging from 21 to 55 feet deep, following U.S. Navy no- decompression limits (USN57). During this period, 48 incidents were reported as possible decompression sickness (DCS), with the majority identified as Type II DCS, which contrasts with previous reports where Type I was more prevalent. The study also examined the potential impact of implementing more stringent no-decompression limits (USN93), assuming diving patterns remained unchanged..
50 - Clearing Up The Confusion About “Deep Stops”
Authors: Erik C. Baker The saying "an ounce of prevention is worth a pound of cure" really applies when it comes to avoiding decompression sickness. The best way to prevent it is by following a proper decompression plan. Technical divers have noticed that including "deep stops" in their diving profiles helps prevent many problems. By understanding how decompression works, we can adjust the model to manage pressure differences better and calculate the safest and deepest stops needed.
04 - Cardiopulmonary changes with moderate decompression in rats
Authors: B.D. Butler, R. Robinson, T. Little, J.E. Chelly, and M-F. Doursout The authors investigated the cardiovascular and pulmonary responses of laboratory rats to moderate decompression stress. Rats were compressed to 616 kPa for 120 minutes and then decompressed at 38 kPa/min. They concluded that moderate decompression profiles cause detectable cardiovascular and pulmonary responses in rats.
11 - Anesthetic and Convulsant Properties of Aromatic Compounds and Cycloalkanes: Implications for Mechanisms of Narcosis
Authors: Zexu Fang, James Sonner, Michael J. Laster, Pompi Ionescu, Lori Kandel, Donald D. Koblin, Edmond I Eger and Michael J. Halsey The authors investigated the anaesthetic and convulsive properties of 16 aromatic compounds (from benzene to 1,3,5-tris(trifluoromethyl)benzene) and four cycloalkanes (from cyclopentane to cyclooctane). Some compounds, such as benzene and cyclopentane, caused excitation, while others, such as perfluorotoluene and cyclohexane, caused convulsions. The results suggest that molecular shape and size provide only limited insight into the structure of the anaesthetic site of action.
12 - Nitric oxide, superoxide, and peroxynitrite: the good, the bad, and the ugly
Authors: Joseph S. Beckman, & Willem H. Koppenol Nitric oxide (NO) is unique among intercellular messengers due to its rapid and isotropic diffusion through tissues, although it cannot be transported through the bloodstream because it is quickly destroyed by oxyhemoglobin. While its direct toxicity is modest, it becomes significantly more toxic when it reacts with superoxide to form peroxynitrite, a selective oxidant that modifies proteins by creating nitrotyrosines. This nitration can disrupt protein assembly, leading to pathological consequences.
16 - The Role of Oxygen Free Radicals in Occupational and Environmental Lung Diseases
Authors: Val Vallyathan & Xianglin Shi This paper explains the role of reactive oxygen species (ROS) in causing lung injuries and diseases. The review highlights both endogenous and exogenous sources of ROS, focusing on occupational and environmental exposures to various chemical substances. ROS can cause cell injury and molecular alterations through various mechanisms, including intracellular signaling and the activation of proinflammatory cytokines. Understanding these processes is crucial for preventing and mitigating lung injuries from acute and chronic toxin exposure.
18 - Decompression comparison of helium and hydrogen in rats
Authors: R. S. Lillo, E. C. Parker, and W. R. Porter This study examined the differences in decompression risk between helium (He) and hydrogen (H2) using 1,607 unanesthetized male albino rats. The rats, subjected to dives with 2% oxygen balance at depths up to 50 ATA and bottom times up to 60 minutes, were decompressed to 10.8 ATA with varying profiles. Using maximum likelihood analysis, the study estimated the relative decompression risk ("potency") and the gas uptake and elimination rate. The findings indicated that H2 has up to 35% greater potency for causing decompression sickness compared to He.
27 - Superoxide Anion Radical (O2), Superoxide Dismutases, and Related Matters
Author: Irwin Fridovich The field of study concerning the biology of superoxide anion radicals and related free radicals has matured significantly. It is now known that superoxide and hydroxyl radicals are produced in living systems, and there are complex defense and repair systems in place to mitigate their harmful effects. New defensive enzymes, such as superoxide dismutase, catalase, and peroxidase, are continually being discovered, along with new targets affected by these radicals. The involvement of these radicals in both physiological and pathological processes is also being established.
30 - High-pressure-mediated dissociation of immune complexes demonstrated in model systems
Authors: Charles Y. Cheung, David J. Green, Gerald J. Litt, and James A. Laugharn, Jr This study demonstrated that high hydrostatic pressure can disrupt immune complexes in two model systems: prostate-specific antigen (PSA) with its antibody and epiglycanin with its specific antibody. The dissociated antibodies were able to rebind to their antigens, indicating that the pressure-induced dissociation was reversible. These findings suggest that high hydrostatic pressure could enhance the sensitivity and specificity of clinical assays.
31 - Diver’s hand: a skin disorder common in occupational saturation diving
Authors: Catrine Ahlén, Ole Jan Iversen, Jan Risberg, Gunnar Volden, Harald Aarset This paper discusses clinical and epidemiological aspects of a condition known as "diver's hand" based on studies conducted in 1990, 1994, and 1995. It reveals that most long-term saturation divers experience this condition at some point in their careers. This condition can occur without prior skin symptoms, and divers may experience other skin issues during saturation periods. Diver's hand appears to be specifically associated with saturation diving.
32 - Salivary Melatonin as a Circadian Phase Marker: Validation and Comparison to Plasma Melatonin
Authors: Athena Voultsios, David J. Kennaway, & Drew Dawsont This study aimed to develop and validate a salivary melatonin radioimmunoassay to determine the phase state of the biological clock, comparing it with traditional plasma assays. The findings support the use of salivary melatonin measurements for phase typing of the melatonin rhythm in humans.
37 - Role of NO in the O2 and CO2 responsiveness of cerebral and ocular circulation in humans
Authors: Leopold Schmetterer, Oliver Findl, Karin Strenn, Ursula Graselli, Johannes Kastner, Hans-Georg Eichler, and Michael Wolzt The study examines the role of nitric oxide (NO) in regulating cerebral and ocular blood flow in response to CO2 and O2 levels. Using L-NMMA in young subjects, researchers measured blood flow velocities and ocular fundus pulsation. L-NMMA reduced pulsations and slightly decreased flow velocities. Hypercapnia increases flow velocities in the middle cerebral artery and fundus pulsation amplitude. The responses were blunted by L- NMMA, indicating NO's role in hypercapnia-induced vasodilation. L-NMMA did not affect hyperoxia-induced changes.
38 - Nitric oxide regulates oxygen uptake and hydrogen peroxide release by the isolated beating rat heart.
Authors: Juan J. Poderoso, Jorge G. Peralta, Constanza L. Lisdero, María Cecilia Carreras, Marcelo Radisic, Francisco Schopfer, Enrique Cadenas, and Alberto Boveris The study examined how nitric oxide (NO) and bradykinin impact myocardial oxygen (O2) uptake in isolated rat hearts. It showed a reduction in O2 uptake with increased NO concentrations, and higher levels of NO led to elevated hydrogen peroxide (H2O2) release and inhibited O2 uptake in isolated rat heart mitochondria. NO was found to hinder electron transfer at cytochrome oxidase and between cytochrome b and cytochrome c, mainly binding to myoglobin and affecting mitochondria.
39 - Identification of infectious Pseudomonas aeruginosa strains in an occupational saturation diving environment
Authors: Catrine Ahlén, Lise Helen Mandal, Ole Jan Iversen This study focuses on skin infections among occupational saturation divers, particularly those caused by Pseudomonas aeruginosa, from 1987 to 1995 in the North Sea. It aims to document the occurrence of P. aeruginosa in these infections, its presence in diving environments, and the relationship between infection strains and environmental isolates.
44 - Lymphocyte subsets and adhesion molecules expression in heatstroke and heat stress.
Authors: Muhammad M. Hammani, Abderrezak Bouchama, Essam Shail, Hassan Y. Aboul-Enein, Sultan Al-Sedaury This study analyzed circulating lymphocyte changes in heatstroke patients before and after cooling, compared to heat-stressed controls. Findings suggest heatstroke causes significant alterations in lymphocyte subsets, which are not entirely normalized by cooling and are unrelated to catecholamine levels. Heat stress results in similar but milder changes, indicating a continuum between heatstroke and heat stress.
45 - Assessment of cardiac autonomic nervous activities during heliox exposure at 24 atm abs.
Authors: Fumio Yamazaki, Keizo Shiraki, Sueko Sagawa, Yutaka Endo, Riko Torii, Hitoshi Yamaguchi, Motohiko Mohri, and Yu-chong Lin This experiment studied the autonomic nervous system in hyperbaric bradycardia. Four male divers were in a heliox environment at 24 atm abs for seven days. Heart and respiratory rates were measured during different phases. Results showed a stable morning heart rate but a decreased nighttime heart rate initially. Parasympathetic activity increased on the first night, but sympathetic activity did not change. Increased parasympathetic activity causes bradycardia during heliox dives. The gradual disappearance of bradycardia may be due to cardiovascular deconditioning.
05 - Haemoconcentration in neurological decompression illness
Authors: A. Boussuges, P. Blanc, F. Molenat, E. Bergmann, J.M. Sainty This study discusses the relationship between haematocrit levels and neurological decompression illness (DCI) in sports divers. It determines if there is a correlation between haematocrit levels and the prognosis of neurological sequelae in divers affected by DCI. It also provides statistical analysis highlighting that a higher haematocrit level is associated with persistent neurological sequelae.
25 - Decompression sickness from saturation diving: a case control study of some diving exposure characteristics
Author: G. Jacobsen, J. E. Jacobsen, R. E. Peterson, J. H. McLellan, S. T. Brooke, T. Nome, A. O. Brubakk This document presents and analyzes data from a comprehensive database of diving activities conducted by a Norwegian offshore diving contractor, focusing on the incidence of decompression sickness (DCS) among divers. It discusses the development of a theory that aims to predict DCS based on exposure factors and describes a study using a case-control design to identify characteristics of dives that resulted in DCS. It also highlights the relationship between pressure changes during dives and the likelihood of DCS, suggesting that some dive characteristics, such as multiple storage depths and significant pressure changes, increase the risk of DCS.
52 - Risk of decompression sickness with patent foramen ovale
Authors: A.A. Bove This study investigates the relationship between the presence of a patent foramen ovale (PFO) and the risk of developing decompression sickness (DCS) in divers. It uses statistical methods, such as Logistic Regression and Bayes' theorem, to analyze data from multiple studies. The findings suggest that while having a PFO increases the odds of developing serious DCS, the overall risk remains small and does not justify routine echocardiographic screening for divers.
53- Intrathoracic pressure changes after Valsalva strain and other maneuvers: implications for divers with patent foramen ovale
Authos: C. Balestra, P. Germonpre, and A. Marroni This paper presents research findings on the risks associated with some physical maneuvers for scuba divers with a patent foramen ovale (PFO). It informs and advises divers, particularly those with PFO, about the potential dangers of performing specific exercises that can lead to paradoxical nitrogen gas emboli due to changes in intrathoracic pressure. It concludes with a recommendation for divers to avoid strenuous exercises after decompression dives to mitigate these risks
03 - Evolution and offshore performances of the Comex Treatment Tables.
Author: Jean Pierre Imbert This document was published during the Workshop on Decompression Illness Treatment. Undersea Biomedical Hyperbaric Society, Palm Beach, Florida - June 1996 Employers must set up contingency plans for any work hazards in commercial diving. Diving companies provide equipment, train staff, and revise recompression procedures for treating decompression sickness (DCS). This presentation assesses the offshore effectiveness of Comex treatment procedures used since 1975.
Author: D. J. Valaik, E. C. Parker, S. S. Survanshi This document is a presentation of the “Real Time Dive Planner, a flexible method of calculation that was approved for use in support of Naval Special Warfare (NSW) diving operations in May 1994
10 - Calculating Decompression in Naval Special Warfare SEAL Delivery Vehicle Diving Operations Utilizing the Real Time Dive Planner
Authors: Michael Knauth, Stefan Ries, Stefan Pohimann, Tina Kerby, Michael Forsting, Michael Daffertshofer, Michael Hennerici, Klaus Sartor This study investigates how a patent foramen ovale may contribute to multiple brain lesions in sport divers who did not report decompression symptoms. It is a prospective double-blind cohort study involving 87 divers with at least 160 scuba dives. The main outcomes measured were brain lesions seen in MRI and the presence and size of patent foramen ovale using echocontrast transcranial Doppler ultrasonography. Findings showed that 25 divers had a right-to-left shunt, with multiple brain lesions found mainly in those with a large patent foramen ovale, suggesting a link to gas embolism.
20 - Cohort study of multiple brain lesions in sport divers: Role of a patent foramen ovale.
29 - Concervative management of gastric rupture following scuba diving
Author: J D Hunter, C A Roobottom, Ph Bryson, C Brown Gastric rupture is an uncommon surgical problem which normally presents with an acute abdomen and peritonism. Aan nusual case following underwater ascent and its conservative management is presented.
36 - The Importance of Deep Safety Stops: Rethinking Ascent Patterns From Decompression Dives
Author: Richard L. Pyle The author of this article believes that deep stops help avoid decompression sickness by controlling bubble size and, therefore, improving safety. He concludes by suggesting divers explore this practice but reminds them to prioritize their own safety.
47 - DCI incidence for surD NDC tables in the range of 48 to 51 metres
Authors: W. Sterkl, N. vinré, and R. Takashima The Netherlands Diving Centre (NDC) created decompression tables, known as DADCODAT (DCD) tables, in 1988 using a specific computational model. These tables aimed for a decompression illness (DCI) rate of no more than 0. 5%. Users were required to report dive data to NDC until 1994, when data collection stopped due to perceived sufficiency. Recently, concerns arose that DCI rates might exceed the acceptable limit after air diving at depths between 45 and 50 msw, especially during NDC courses, prompting further investigation.
Author: Erich W Russi Pulmonary barotrauma (PBT) of ascent is a feared complication in compressed air diving. Although certain respiratory conditions are thought to increase the risk of suffering PBT and thus should preclude diving, in most cases of PBT, risk factors are described as not being present. The purpose of the study was to evaluate factors that possibly cause PBT. Design. The authors analyzed 15 consecutive cases of PBT with respect to dive factors, clinical and radiologic features, and lung function. They were compared with 15 cases of decompression sickness without PBT, which appeared in the same period.
48 - Diving and the risk of barotrauma.
09 - Effects of N2O narcosis on breathing and effort sensations during exercise and inspiratory resistive loading.
Author: D.M. Fothergill, & A. Carlson This study on thirteen male US Navy divers revealed that breathing 23% nitrous oxide moderately affected respiratory effort, but did not impair exercise tolerance or depress ventilatory reflexes during resistive breathing exercises.
The Convention for the Protection of Human Rights and Dignity of the Human Being with regard to the Application of Biology and Medicine, commonly known as the Oviedo Convention, is an international treaty aimed at protecting human rights and dignity in the biomedical field. It was opened for signature in Oviedo, Spain, on April 4, 1997.
21 - Convention for the Protection of Human Rights and Dignity of the Human Being with regard to the Application of Biology and Medicine: Convention on Human Rights and Biomedicine (Convention of Oviedo)
Author: Shi Zhnog-yuan This study investigated the safety and performance of helium-nitrogen-oxygen excursions from nitrox saturation at significant depths. Four divers were saturated in nitrogen-oxygen conditions and completed excursions to 60 and 80 msw using a specific trimix gas. Decompression procedures based on Hamilton's methods were followed, yielding effective results. While some bubble grades persisted post-dive, no major symptoms were reported, suggesting that deep diving with helium-rich mixtures is feasible and safe with proper protocols.
51 - Experiment of nitrox saturation diving with trimix excursion