scientific-2003

Scientific papers 2003

15 - Independent cerebral vasoconstrictive effects of hyperoxia and accompanying arterial hypocapnia at 1 ATA - Published by the American Physiological society.

Document written by Thomas, F. Floyd, James M. Clark, Robert Gelfand, John A. Detre, Sarah Ratcliffe, Dimitri Guvakov, Christian J. Lambertsen, and Roderic G. Eckenhoff Breathing 100% O2 at 1-atmosphere absolute (ATA) is known to be associated with a decrease in cerebral blood fow (CBF). It is also accompanied by a fall in arterial PCO2 leading to uncertainty as to whether the cerebral vasoconstriction is totally or only in part caused by arterial hypocapnia. The team tested the hypothesis that the increase in arterial PO2 while O2 was breathed at 1.0 ATA decreases the cerebral blood fow (CBF) independently of a concurrent fall in arterial PCO2 ..

Authors: A. O Brubakk, A. J. Arntzen, B. R. Wienke, S. Koten: This study examined how different decompression profiles affect bubble formation after surface decompression using oxygen. Three profiles were tested on a pig after an air dive: a USN staged profile, a linear continuous profile matching the USN time, and a faster linear profile. The study found that the faster linear profile resulted in fewer bubbles in the pulmonary artery and jugular vein, aligning with model simulations.

22 - Human factors in decompression sickness in compressed air workers in the united Kingdom 1986-2000 - A case-control study and analysis using the HSE decompression database - published by the UK Health and Safety Executive.

This report describes a case-control study of UK compressed air workers in which subjects with repetitive DCS during a single compressed air project were matched to two control groups. Further to this, an analysis of the Health and Safety Executive (HSE) Decompression Database 1986-2000 was undertaken to examine the relative contribution of those workers with repetitive DCS to the overall number of DCS episodes in the UK during the study period.

17 - Heat stress attenuates air bubble-induced acute lung injury: a novel mechanism of diving acclimatization - Published by the American Physiological society (author-released).

Authors: Kun-Lun Huan, Chin-Pyng Wu, Yin-Li Chen, Bor- Hwang Kang, & Yu-Chong Lin Diving acclimatization refers to reduced susceptibility to acute decompression sickness (DCS) in individuals undergoing repeated compression-decompression cycles. The authors postulated that mechanisms responsible for acclimatization are similar to that of stress preconditioning. In this study, we investigated the protective effect of prior heat shock treatment on air embolism-induced lung injury and DCS incidence in rats.

19 - Heat-induced increases in endothelial NO synthase expression and activity and endothelial NO release - Published by the Undersea & Hyperbaric Medical Society (Author-released).

Authors: M. B. Harris, M. A. Blackstone, Hong Ju, V. J. Venema, & R. C. Venema. Endothelial nitric oxide (NO) synthase (eNOS) is the primary source of NO production in the cardiovascular system. It is a key regulator of systemic blood pressure, blood vessel proliferation, and vascular lesion formation. eNOS is regulated by numerous mechanisms, including subcellular location, phosphorylation, and protein-protein interactions. This study is the continuation of previous experiences regarding this point. Understanding the phenomenons described is essential to understand divers' physical condition and some phenomena linked to decompression accidents.

11 - Neuronal sensitivity to hyperoxia, hypercapnia, and inert gases at hyperbaric pressures - Published by the American Physiological Society (Author-released)

Authors: Jay B. Dean, Daniel K. Mulkey, Alfredo J. Garcia, Robert W. Putnam, and Richard A. Henderson As ambient pressure increases, hydrostatic compression of the central nervous system, combined with increasing levels of inspired PO2, PCO2, and N2 partial pressure, has deleterious effects on neuronal function, resulting in O2 toxicity, CO2 toxicity, N2 narcosis, and high-pressure nervous syndrome. The cellular mechanisms responsible for each disorder have been difficult to study by using classic in vitro electrophysiological methods, due to the physical barrier imposed by the sealed pressure chamber and mechanical disturbances during tissue compression.

7 - Measurement of fatigue following 18msw dry chamber dives breathing air or enriched air nitrox. - Published by the Undersea & Hyperbaric society (Author-released)

Authors: RJD Harris, D.J Doolette, D.C Wilkinson, D.J. Williams Many divers report less fatigue following diving, breathing oxygen-rich N2 - O2 mixtures than breathing air. In this double-blinded, randomized controlled study, 11 divers breathed either air or enriched Air Nitrox 36% O2 during an 18 msw chamber dive for a bottom time of 40 minutes. Two periods of exercise were performed during the dive. Divers were assessed before and after each dive.

14 - Autonomic Mechanisms of Bradycardia During Nitrox Exposure at 3 Atmospheres Absolute in Humans - Published by Aviation Space and environmental medicine (author-released)

Authors: Fumio Yamazaki, Futoshi Wada, Ken Nagaya, Riko Torii, Yutaka Endo, Sueko Sagawa, HitoshiYamagushi, Motohiko Mohri, Yu-chong Lin, & Keizo Shiraki. This experiment examined the involvement of the autonomic nervous systems and intrinsic components in the occurrence of hyperbaric bradycardia. Eight male divers were exposed to an N2 - O2 (Nitrox) environment at 3 atmospheres (ATA). The heart rate (HR), plasma norepinephrine (NE), and spectral power of the variability of the cardiac interval were measured during a 4-day pre- dive control period, a seven-day saturation period at 3 ATA, and a 4-day post-dive period.

10 - A comparison of oxygen decompression tables for use in compressed air work - Published by Unimed Scientific Limited (Company disolved in 2024) / UK HSE

Published by: Unimed Scientific Limited for the UK HSE This study was commissioned to compare a number of tables used for oxygen decompression in compressed air tunneling work. It was undertaken by Unimed Scientific Limited at the request of UK Health and Safety Executive.

Authors: Mirit Eynan, Yehuda Arieli, Ran Arieli, & Arieth Bomzon The purpose of this study was to measure the effect of 24 h breathing 100% O2 in normobaric conditions on energetic efficiency in the trained rat. The results suggested that prolonged exposure to hyperoxia induces a reduction in the energetic efficiency of trained rats.

Author: Valerie Flook The work described in this report continues the one published by Unimed Scientific Ltd in December 2002 for “Well Ops UK Ltd”. In this report, Valerie Flook describes changes to procedures for upward excursions, that were not discussed in the previous document.

Authors: David J Doolette and Simon J Mitchell) Isolated inner ear decompression sickness (DCS) is recognised in deep diving involving breathing of helium- oxygen mixtures, particularly where breathing gas is switched to a nitrogen-rich mixture during decompression. The biophysical basis for this selective vulnerability of the inner ear to DCS has not been established. A compartmental model of inert gas kinetics in the human inner ear was constructed from anatomical and physiological parameters described in the literature and used to simulate inert gas tensions in the inner ear during deep dives and breathing gas substitutions that have been reported to cause inner ear DCS.

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6 - Change of occurrence of type 1 and type 2 decompression sickness of divers treated at the Croatian Naval Medical Institute in the period from 1967 to 2000 - Published by the International maritime health (author-realeased).

Authors: Dejan Andric, Nadan M. Petri, Hrvoje Stipancevic, Lena Vranjkovic Petri, Hasan Kovacevic Between 1991 and 2002, Croatia experienced a significant change in the incidence of type 1 and type 2 decompression sickness (DCS) among divers. This shift has been attributed to the widespread use of diving computers and advanced gas mixtures, which allow for longer and deeper dives, thereby increasing the likelihood of decompression-related issues. The results of this study are particularly significant because type 2 decompression sickness can cause permanent neurological damage.

12 - Report of the Decompression Illness Adjunctive Therapy Committee of the Undersea and Hyperbaric Medical Society - including Proceedings of the Fifty-Third Workshop of the Undersea and Hyperbaric Medical Society - Published by the Undersea & Hyperbaric Medical Society

This workshop was held at Duke University on January 23 and 24, 2002, with a focus on decompression illness in humans and animal models, as well as adjunctive therapies and research opportunities.

4 - Differential Diagnostic Problems of Decompression Sickness - Examples from Specialist Physicians’ Practices in Diving Medicine - Published by Science Direct - Archives of Medical Research (Author-released)

Authors: Nadan petri & Dejan Andrie This document discusses the increasing challenge of diagnosing decompression sickness (DCS) in Croatia due to the rising number of divers. Many physicians at remote diving sites have only basic knowledge of diving medicine and lack experience. Language barriers also hinder the medical history and examination of foreign divers. Consultations at the Naval Medical Institute (NMI) in Spli significantly aided in accurate diagnosis and treatment. The text includes six case studies from NMI Archives illustrating how biases, panic, and inexperience can complicate DCS diagnosis.

5 - Increased oxygen before and during decompression reduces bubble formation in rats - Published by the Undersea & Hyperbaric society (Author-released)

Authors: S. Skogland, L.E.B. Stuhr, H. Sundland, S. Marstein, A. Hope This study aimed to test whether increasing oxygen partial pressure shortly before and during decompression from hyperbaric pressures would reduce venous gas bubble formation in rats. Results showed significantly fewer bubbles in exposure with increased O2 partial pressure, suggesting that increasing oxygen partial pressure before and during decompression may lead to safer decompression in conscious rats.

8 - Incidence of probable occupational asthma and changes in airway calibre and responsiveness in apprentice welders - Published by the European Repiratory journal (author-released)

Authors: M. El-Zein, J-L. Malo, C. Infante-Rivard, D. Gautrin This study aimed to determine the incidence of probable occupational asthma (OA), bronchial obstruction, and hyperresponsiveness among 286 students entering a welding apprenticeship program. Out of 194 subjects with complete data, the incidence of probable OA was 3%, and bronchial hyperresponsiveness was 11.9%. There was a significant decline in lung function, with an average 8.4% drop in forced expiratory volume percent predicted. The study suggests early pulmonary function changes due to welding exposure, but the long-term chronic effects need further exploration.

Author: Michael G Costigan Hydrogen sulphide (H2S) is a toxic gas that smells like rotten eggs and poses a significant risk in various industries, especially in confined spaces such as manholes and sewers. High concentrations (>1000 ppm) can quickly cause unconsciousness and death. There are numerous reports of fatalities due to H2S exposure. Even low concentrations (<10 ppm) can affect health by interfering with cellular respiration. The UK updated occupational exposure limits for H2S to reduce these health risks.

23 - Involvement of Nitric Oxide and Hyperbaric Oxygen in the Pathogenesis of Cyclophosphamide-Induced Hemorrhagic Cystitis in Rats - Published by the American Urological Association - Published by the American Urological Association

Authors: hmet Korkmaz, sükrü Öter, Salih Deveci, Taner Özgürtas, Turgut Topal, Serdar Sadır, and Hayati Bilgiç This study investigated the role of nitric oxide and hyperbaric oxygenation in developing and treating cyclophosphamide-induced hemorrhagic cystitis in rats. The study concluded that inducible nitric oxide synthase plays a crucial role in the pathogenesis of cyclophosphamide-induced cystitis, and hyperbaric oxygen aids in bladder repair rather than protection.

3 - Right-to-left shunt and risk of decompression illness with cochleovestibular and cerebral symptoms in divers: Case control study in 101 consecutive dive accidents - Published by Lippincott Williams & Wilkins (Author-released)

Authors: Emmanuel Cantais, Pierre Louge, Alain Suppini, Philip P. Foster, Bruno Palmier This medical study investigated the role of right-to-left shunt in divers with decompression illness using transcranial Doppler ultrasonography to determine the association between right-to-left shunt and various types of decompression illness, such as cochleovestibular and cerebral decompression illness, and to suggest paradoxical embolism as a potential mechanism for these conditions. It provides detailed statistical analysis and conclusions drawn from the study, indicating that a significant right-to-left shunt is associated with an increased incidence of certain types of deco illness.

13 - SARMAC V 2003 abstracts - Discussants: The effects of nitrogen narcosis on metacognition in divers - Published by SARMAC

Authors: Conference: Society for Applied Research in Memory and CognitionAt: Aberdeen, ScotlandAffiliation: University of Plymouth This symposium includes reports on recent research on various topics related to cognition in emotionally disordered states, including the interpretation of facial expressions, the interpretation and recall of verbal material, autobiographical memory, and the generation of mental models.

20 - Change in strategy of solving psychological tests: Evidence of nitrogen narcosis in shallow air-diving. - Published by the Undersea & Hyperbaric Medical Society (Author-released).

Authors: N.M. Petri Research on nitrogen narcosis effects indicates that psychomotor disturbances can occur at depths not typically regarded as hazardous. Testing involved experienced divers exposed to varying hyperbaric pressures showed significant performance decrements in various tasks. The findings imply potential risks for underwater operations requiring precision, highlighting the need to reassess safety standards related to nitrogen narcosis.

2 - Activation of a glycine transporter on spinal cord neurons causes enhanced glutamate release in a mouse model of amyotrophiclateral sclerosis - Published by the British Journal of Pharmacology (Nature)

Authors: Luca Raiteri, Egle Paolucci, Simona Prisco, Maurizio Raiteri & Giambattista Bonanno The study compared glycine-evoked [3H]D-aspartate and [3H]GABA release from spinal cord synaptosomes in SOD1-G93A(+) ALS model mice (advanced pathology) versus controls. In controls, glycine concentration- dependently evoked release of both via glycine transporter activation, as shown by blockade with glycyldodecylamide but not receptor antagonists. In SOD1-G93A(+) mice, glycine-evoked [3H]D-ASP release was significantly enhanced versus controls, while [3H]GABA release was unchanged.