ILO Home
Go to the home page
Site map | Contact us Français | Español
view in a printer-friendly format »

Hypobaric pressure - 34 entries found

Your search criteria are

  • Hypobaric pressure

2009

CIS 10-0116 Brandt M.S., Morrison T.O., Butler W.P.
Decompression sickness rates for chamber personnel: Case series from one facility
During 2004, an epidemic of decompression sickness (DCS) was observed among participants of a United States air force physiological training programme. There were 10 cases of chamber-induced altitude DCS observed. Internal and external investigations focused on time, place, person, and environment. Four were students and six were inside observers. Four were women and six men. Among the inside observers, examining the monthly exposures load against DCS suggested a dose-response relationship. Poisson regression analysis demonstrated a statistically significant 2.1-fold rise in DCS risk with each monthly exposure. Consequently, the number of exposures per month may need to be considered when devising inside observer schedules.
Aviation, Space, and Environmental Medicine, June 2009, Vol.80, No.6, p.570-573. 11 ref.

2002

CIS 03-399 Pilmanis A.A., Webb J.T., Kannan N., Balldin U.
The effect of repeated altitude exposures on the incidence of decompression sickness
Repeated hypobaric exposures in a single day occurring during parachute training, hypobaric chamber training, unpressurized flight and extravehicular space activity can cause decompression sickness (DCS). To test the hypothesis that short exposures with and without ground intervals would result in a lower incidence of DCS than a single exposure of equal duration, 32 subjects were exposed to three different hypobaric exposures: a single 2h continuous exposure (condition A, control); four 30min exposures but no ground interval between the exposures (condition B); four 30min exposures and a 60min period of ground interval between exposures (condition C). All exposures were to a simulated altitude of 7500m with 100% oxygen breathing. Subjects were examined for symptoms of DCS and precordial venous gas emboli (VGE). Results indicate that repeated simulated altitude exposures to 7500m significantly reduce DCS and VGE incidence compared with a single continuous exposure of equivalent duration.
Aviation, Space, and Environmental Medicine, June 2002, Vol.73, No.6, p.525-531. Illus. 28 ref.

2000

CIS 01-1597
Secretaría del Trabajo y Previsión Social
Official Mexican Standard - Occupational exposure to abnormal environmental pressure: Safety and health conditions [Mexico]
Norma Oficial Mexicana - Exposición laboral a presiones ambientales anormales - Condiciones de seguridad e higiene [México] [in Spanish]
Contents of this standard: scope (all work activities which include diving, or which involve work under low atmospheric pressure); definitions and symbols; obligations of employers and exposed workers; safety and health conditions of activities performed under low atmospheric pressure; safety and health conditions of activities under diving-type high atmospheric pressure; verification systems. In annexes: decompression tables and other limits connected with work under abnormal atmospheric pressure.
Internet copy, 2000. 18p. + annexes (not included in pagination).
http://www.stps.gob.mx/04_sub_prevision/03_dgsht/normatividad/normas/nom-014.htm [in Spanish]

1999

CIS 00-576 West J.B.
Oxygen enrichment of room air to improve well-being and productivity at high altitude
Increasingly, commercial and scientific activities, such as mining and observational astronomy, are taking place at very high altitudes, up to 5,000m. Frequently, workers commute to these locations from much lower altitudes. In addition, large numbers of people permanently live and work at high altitudes. The hypoxia of high altitude impairs sleep quality, mental performance, productivity and general well-being. The proposed solution is to inject oxygen into enclosed work areas through the air-conditioning system. An increase in oxygen concentration by one percentage point (e.g. from 21% to 22%) decreases the equivalent altitude by about 300m, i.e. a room at an altitude of 4,500m containing 26% oxygen is effectively at an altitude of 3,000m. This innovative technique promises to improve productivity and well-being at high altitudes.
International Journal of Occupational and Environmental Health, July-Sep. 1999, Vol.5, No.3, p.187-193. Illus. 23 ref.

1997

CIS 00-428 Diseases associated with high altitude
Patología en la altura [in Spanish]
This publication contains a collection of studies performed in the general hospital of Chúlec, Peru, situated at an altitude of 3,730 meters, on a series of diseases associated with high altitude. These studies are classified under the following headings: paediatrics, general medicine, surgery, gynaecology and obstetrics, and occupational medicine. In the latter, studies were performed on acoustic trauma, auditory fatigue and prevalence of occupational deafness, assessment of the visual function of metal miners and levels of arsenic poisoning of exposed workers in a metallurgy plant.
Oficina de Comunicaciones y RR.PP. de CENTROMIN PERÚ S.A., Peru, [1997] . 254p. Illus. Bibl.ref.

CIS 97-2088 Sulaiman Z.M., Pilmanis A.A., O'Connor R.B.
Relationship between age and susceptibility to altitude decompression sickness
Data on 1,299 subject flight exposures in altitude chambers conducted during 1983-1994 were examined. Ages of subjects ranged 18-48 years. There was a trend towards increased susceptibility to decompression sickness with increasing age, with a particularly strong trend for individuals over 42 years of age.
Aviation, Space, and Environmental Medicine, Aug. 1997, Vol.68, No.8, p.695-698. Illus. 15 ref.

CIS 97-1384 Loftin K.C., Conkin J., Powell M.R.
Modeling the effects of exercise during 100% oxygen prebreathe on the risk of hypobaric decompression sickness
Previous studies on the effect of exercise during oxygen prebreathe on the incidence of hypobaric decompression sickness (DCS) were analyzed, and a statistical model was developed as a predictive tool for DCS. A dose-response probability tissue ratio (TR) model was created for two groups: prebreathe with exercise and resting prebreathe. Results suggested that exercise during prebreathe increases tissue perfusion and nitrogen elimination approximately 2-fold and markedly lowers the risk of DCS. The model provides a useful planning tool for developing appropriate prebreathe exercise protocols and for predicting DCS for astronauts.
Aviation, Space, and Environmental Medicine, Mar. 1997, Vol.68, No.3, p.199-204. 23 ref.

1996

CIS 98-1525 Gunga H.C., Röcker L., Behn C., Hilderbrandt W., Koralewski E., Rich I., Schobersberger W., Kirsch K.
Shift working in the Chilean Andes (>3600m) and its influence on erythropoietin and the low-pressure system
Topics: Chile; high altitude; hypoxia; intermittent work; physiology of blood; shift work; venous blood pressure.
Journal of Applied Physiology: Respiratory, Environmental and Exercise Physiology, 1996, Vol.81, p.846-852. Illus. 29 ref.

CIS 96-1015 Conkin J., Kumar V., Powell M.R., Foster P.P., Waligora J.M.
A probabilistic model of hypobaric decompression sickness based on 66 chamber tests
An approach to estimating the probability of decompression sickness (DCS) in astronauts performing extravehicular activities (EVAs) is described. Data from 66 hypobaric chamber tests (211 cases of DCS in 1075 exposures) were analyzed. Variables considered were denitrogenation prior to decompression, magnitude of the decompression, exercise after decompression, and length of the EVA. Probability models were fitted using techniques from survival analysis. Constant probability of DCS was better described by tissue ratios that decrease as ambient pressure after decompression decreases, a conclusion supported by other studies.
Aviation, Space, and Environmental Medicine, Feb. 1996, Vol.67, No.2, p.176-183. 20 ref.

CIS 96-1018 Basu C.K., Selvamurthy W., Bhaumick G., Gautam R.K., Sawhney R.C.
Respiratory changes during initial days of acclimatization to increasing altitudes
Daily changes in respiratory function were monitored in 16 male subjects at sea level and at high altitudes of 3110m, 3445m, and 4177m. Identical studies were carried out among acclimatized subjects staying at 3110m and 4177m for two years. Respiratory function values are tabulated for each altitude. Initial respiratory adjustment occurred by day 3 at 3110m and showed a further decrement at 4177m with a cyclic variation on day 6. Respiratory adaptation to hypoxia in acclimatized subjects were different at 3110m and 4177m.
Aviation, Space, and Environmental Medicine, Jan. 1996, Vol.67, No.1, p.40-45. Illus. 31 ref.

1995

CIS 96-332 Radiation exposure and high-altitude flight
This report reviews current knowledge about ionizing radiation levels expected in high-altitude flight and the risk of radiation-induced cancer and developmental effects in the embryo-foetus. Dose rates at different altitudes are discussed along with biological effects, limitations on current risk estimates, estimates of risk to crew and passengers, and radiation protection philosophy. Equivalent dose rates at higher altitudes are two to three times those received at current aircraft altitudes. Recommendations are made for further research into levels of radiation exposure, potential biological effects and the development of appropriate protection guidelines.
National Council on radiation Protection and Measurements, 7910 Woodmont Avenue, Bethesda, MD 20814-3095, USA, July 1995. v, 25p. Illus. 38 ref. Price: USD 15.00.

CIS 95-2300 Ward M.P., Milledge J.S., West J.B.
High altitude medicine and physiology
Contents of this manual: the human response to altitude; ventilatory response to hypoxia and carbon dioxide; lung diffusion; cardiovascular system; haematology; blood gas transport; peripheral tissues; exercise; limiting factors at extreme altitude; sleep; nutrition and intestinal function; the endocrine and renal systems; central nervous system; high-altitude populations; mountain sickness; high-altitude pulmonary oedema, cerebral oedema and retinal haemorrhage; vascular disorders; thermal balance and its regulation; reaction to cold; hypothermia; local cold injury; accidents, surgical emergencies and anaesthesia; skiing injuries and rescue in the mountains; heat injury and solar radiation; medical conditions at high altitude - leisure and commercial activities; fitness and performance in the mountains; practicalities of field studies.
Chapman & Hall, 2-6 Boundary Row, London SE1 8HN, United Kingdom, 2nd ed., 1995. xviii, 618p. Illus. Bibl.ref. Index. Price: GBP 69.00.

1994

CIS 94-2085 Kumar K.V., Powell M.R.
Survivorship models for estimating the risk of decompression sickness
The applicability of survival analysis for modelling the risk of decompression sickness (DCS) is illustrated by using data from earlier studies of hypobaric chamber exposures. A method for estimating the overall incidence-free survival rates for circulating microbubbles, symptoms and test aborts is described and the results are discussed. Survival analysis is shown to have certain advantages over other methods for modelling the risk of DCS.
Aviation, Space, and Environmental Medicine, July 1994, Vol.65, No.7, p.661-665. 15 ref.

1992

CIS 93-1352 Rudge F.W.
The role of ground level oxygen in the treatment of altitude chamber decompression sickness
Data were collected on the use of ground-level oxygen in the treatment of altitude chamber decompression sickness among US Air Force personnel during 1989-91. Data included age, sex, time of symptom development, type of initial treatment and response to ground-level oxygen administration. Of the 175 cases treated with ground-level oxygen, 40 failed to resolve and were treated with compression therapy. The remaining 135 all resolved with ground-level oxygen, obviating the need for hyperbaric oxygenation. Factors associated with a favourable response to this type of treatment are discussed.
Aviation, Space, and Environmental Medicine, Dec. 1992, Vol.63, No.12, p.1102-1105. 12 ref.

CIS 93-1042 Kumar K.V., Waligora J.M., Gilbert J.H.
The influence of prior exercise at anaerobic threshold on decompression sickness
In a study to examine the effects of exercise prior to decompression on the incidence of altitude decompression sickness (DCS), 39 subjects exercised at their predetermined anaerobic threshold levels for 30min each day for three days prior to exposure to an altitude of 6,400m in a hypobaric chamber. No significant difference in DCS preferences was found.
Aviation, Space, and Environmental Medicine, Oct. 1992, Vol.63, No.10, p.899-904. 26 ref.

CIS 93-305 Crowley J.S., Wesensten N., Kamimori G., Devine J., Iwanyk E., Balkin T.
Effect of high terrestrial altitude and supplemental oxygen on human performance and mood
In a study to investigate the effects of high terrestrial altitude on human performance, 13 male soldiers ascended in 10min from sea level to 4,300m (simulated) and remained there for two and a half days. Subjects carried out cognitive tests and mood tests and completed a questionnaire to assess the severity of acute mountain sickness (AMS) symptoms. Following rapid ascent, performance was most affected during the first eight hours. Recovery of cognitive function was slower in subjects suffering from AMS.
Aviation, Space, and Environmental Medicine, Aug. 1992, Vol.63, No.8, p.696-701. 26 ref.

1991

CIS 92-1012 Seigneuric A.
Pathology associated with altitude and flights in the atmosphere and in space
Pathologie liée à l'altitude et aux vols dans l'atmosphère et dans l'espace [in French]
Following a summary of the hazards associated with high altitude (oxygen rarefaction and hypoxia, cold, humidity and radiation), acute pathological effects are examined: mountain sickness, acute pulmonary oedema, cerebral oedema and vascular complications, particularly in the retina. Effects of a prolonged stay at altitude, which may result in either a satisfactory adaptation or Monge disease, are also outlined. The effects of flights in the atmosphere and in space are dependent on the duration and altitude of the flight and require the protective measures described.
Encyclopédie médico-chirurgicale, Toxicologie-Pathologie professionnelle, 1991. 10p. 77 réf.

CIS 92-300 Butler F.K.
Decompression sickness presenting as optic neuropathy
Report of a case of acute optic nerve dysfunction seen in a parachutist after repeated hypobaric exposures. The patient made 2 to 4 high altitude exposures per day for 4 days in an unpressurised aircraft at a maximum altitude of 3,636-3,939m. Resultant symptoms included persistent headache, paracentral scotoma and decreased visual acuity in the left eye. Symptoms improved promptly following treatment with recompression and hyperbaric oxygen therapy. This is believed to be the first case of decompression sickness presenting as optic neuropathy.
Aviation, Space, and Environmental Medicine, Apr. 1991, Vol.62, No.4, p.346-350. Illus. 11 ref.

CIS 92-298 Rush W.L., Wirjosemito S.A.
Decompression sickness: Risk factors and the monoplace chamber - A case report
This case report of serious decompression sickness (DCS) with pulmonary and neurological manifestations illustrates the principles and concerns related to the use of monoplace chambers for the treatment of DCS. Closely timed recurrent altitude exposure is discussed as a risk factor for DCS, and a newly defined risk factor associated with the menstrual phase is considered relevant to this case. It is recommended that arrangements be made early in the management of DCS cases for transfer to a chamber which can provide definitive therapy.
Aviation, Space, and Environmental Medicine, May 1991, Vol.62, No.5, p.414-417. 19 ref.

1990

CIS 92-297 Rudge F.W.
Relationship of menstrual history to altitude chamber decompression sickness
Records at the USAF School of Aerospace Medicine were reviewed to determine the relationship between the incidence of altitude chamber decompression sickness (DCS) in females and menstrual history. A significant inverse linear correlation was noted between the number of days since the start of the last menstrual period and the incidence of DCS. The underlying mechanism for the correlation between menstrual cycle and susceptibility to development of DCS is unknown. It is concluded that women are at higher risk of developing altitude related DCS during menses, with the risk decreasing linearly as the time since last menstrual period increases.
Aviation, Space, and Environmental Medicine, July 1990, Vol.61, No.7, p.657-659. Illus. 7 ref.

CIS 91-296 Devine J.A., Forte V.A., Rock P.B., Cymerman A.
The use of typanometry to detect aerotitis media in hypobaric chamber operations
Diagnosis and quantification of aerotitis media were performed using a modified commercially-available tympanometer under hypobaric conditions. Subjects were 22 males and 9 females, 22-43 years of age, who were tested in each ear with the tympanometer prior to and after exposure, sequentially at the barometric pressue plateaus of 706, 656, 609, 586, 564, and 522mm Hg, and following an induced ear block during a 1-min descent from 522 to 586mm Hg. Each subject was examined once either alone or in pairs during a 90-min exposure. Aerotitis media was detected using tympanometry at simulated altitude as evidenced by the difference between measurements made during induced ear blocks and those made prior to inducement, as well as following relief of the pressure differential with the Valsolva manoeuvre. There were no significant differences between pre- and post-induced aerotitis media values at 586mm Hg, or between pre- and post-hypobaria. Thus, tympanometry can be a valuable tool in managing aerotitis media in the aeromedical environment.
Aviation, Space, and Environmental Medicine, Mar. 1990, Vol.61, No.3, p.251-255. Illus. 20 ref.

1989

CIS 91-1493 Risks of working in high mountain locations
Los riesgos del trabajo en la alta montaña [in Spanish]
Training manual. Contents: jobs at high altitudes; the Cordillera environment (high winds; action of water, snow and ice; reduced air pressure); proper work practices (establishing camp; selection of personnel; construction of camps; safety organisation); dangers of transport at high altitudes; work in cold environments; protection against avalanches; emergency planning.
Asociación Chilena de Seguridad, Casilla 14565, Correo Central, Santiago, Chile, Sep. 1989. 33p. Illus.

1988

CIS 90-2082 Mekjavic I.B., Banister E.W., Morrison J.B.
Environmental ergonomics: sustaining human performance in harsh environments
This book containing a selection of papers presented at the 2nd International Environmental Ergonomics Conference, held at Whistler, British Colombia (Canada), on 21-25 July 1986 offers a collaborative approach to the study of human performance in the face of harsh environments such as equatorial and polar regions, ocean floors and outer space, where hot, cold, wet, high- and low- pressure and other extreme conditions affect the body's physiological and cognitive functions to a significant degree.
Taylor and Francis Ltd., Rankine Road, Basingstoke Hants RG24 OPR, United Kingdom, 1988. 412p. Illus. Bibl. Index. Price: GBP 39.00.

1986

CIS 86-1967 Vogel H.
Diseases due to differences in environmental pressure
Maladies dues à des variations de la pression ambiante [in French]
The 2 parts of this very detailed document present the following subjects: physical principles and laws; sources of risk (diving, high-pressure environments, high altitudes); pathogenesis and clinical tables (barotrauma, effects of gases dissolved in the body under increased pressure, gas bubbles in blood and body tissue during a rapid fall in air pressure, effects of oxygen deprivation, deaths during diving); medical and therapeutic prevention; insurance law; accident rates; legal case studies.
Caisse nationale suisse d'assurance en cas d'accidents, case postale, 6002 Luzern, Switzerland, Sep. 1986, n°8, 2 parts, 139p. Illus. 37 ref.

1982

CIS 84-1131 Kolesari G.L., Kindwall E.P.
Survival following accidental decompression to an altitude greater than 74,000 feet (22,555m)
The accident occurred in an industrial vacuum chamber. The victim experienced burst lung, massive decompression sickness, and sustained ebulism (vaporisation of blood). He remained "at altitude" for as much as 3-5min. He was still profoundly unconscious 5.5h after the accident. After treatment in a hyperbaric chamber with recompression he eventually recovered. Substantial barotrauma to the tissues was present. This is probably the most severe case of unprotected human decompression with survival reported to date.
Aviation, Space, and Environmental Medicine, Dec. 1982, Vol.53, No.12, p.1211-1214. Illus. 3 ref.

1981

CIS 82-1999 Mielle F.
Work at high altitudes and underground or underwater: Clinical physiopathology and practical deductions
Altitude et profondeur: physiopathologie clinique et déductions pratiques [in French]
Physiological and pathological effects of altitude: hypoxia, physical factors, dynamic conditions, space flight; major pathological syndromes due to altitude. Contraindications (flight crews; periods spent at high altitudes). Physiopathology of underground work: minework, speleology. General considerations on hyperbaric physiopathology (physiology, decompression tables). Free diving, compressed-air and compressed-gas diving. Basic information on treatment of diving accidents. Contraindications for diving.
Cahiers de médecine interprofessionnelle, 4th quarter 1981, Vol.21, No.84, p.25-63. Illus. 45 ref.

CIS 81-1482 Colin J.
Physiopathology of high altitudes and atmospheric and space flights
Physiopathologie liée à l'altitude et aux vols dans l'atmosphère et l'espace. [in French]
Revised text of an article. The 1st part deals with: high-altitude hypoxia (effects and tolerance) and high altitude pathology (barotraumatic effects, aviation decompression syndrome, ebullism, prevention of high-altitude risks). The 2nd part covers: the physiopathology of acceleration (haemodynamic effects of prolonged acceleration, mechanical effects of short-term acceleration and the effects of acceleration on spatial orientation, posture and movement mechanisms). The 3rd part examines the three main mechanisms behind physiopathological reactions to weightlessness, and their prevention.
Encyclopédie médico-chirurgicale, maladies et agents physiques, 18 rue Séguier, 75006 Paris, France, 1981. 16p. 30 ref.

1980

CIS 82-1823 Prevention of furnace implosions in multiple burner boiler-furnaces
This standard, adopted as an American National Standard 28 July 1980, establishes minimum standards for the design, installation and operation of boiler-furnaces, their fuel burning, air supply and combustion products removal systems, which include induced-draught fans and related control equipment, to prevent furnace implosions. It offers 2 methods for minimising the risk of negative furnace draught in excess of furnace structural capability: design of the furnace and flue gas removal system so that the low gas flow maximum head capability of the induced-draught fan system with ambient air does not exceed the design pressure of furnace ducts and associated equipment; or provision of a furnace pressure control system, draught fan directional blocking, or run-backs. Contents: equipment requirements (furnace structural design; combustion products removal; furnace pressure control system); sequence of operations; functional and system requirements for interlock and alarm systems.
National Fire Protection Association, Batterymarch Park, Quincy, MA 02269, USA, 1980. 18p. Illus. Price: US-$5.00.

1978

CIS 79-41 Kryger M., Aldrich F., Reeves J.T., Grover R.F.
Diagnosis of airflow obstruction at high altitude.
Many workers in the US mining industry work at high altitudes (>3,000m). A large molybdenum (hard rock) mine in Colorado (altitude 3,100m) instituted respiratory screening of all newly hired and current employees in 1976. Evaluations included a respiratory questionnaire, spirometry, and a chest X-ray. The authors evaluated all men screened between March 1976 and April 1977 (approximately 1,600 subjects) and then excluded all subjects who had smoked cigarettes, who had a history of lung disease, or whose present or previous job was in an environment of mineral dusts or chemical fumes, leaving 126 nonsmokers believed to be free of lung disease. The authors conclude from the results of measurements (FVC; FEV1; FEV1/FVC, mean forced expiratory flow) that using predicted sea level values for spirometry done at high altitude, underestimation of airway obstruction may result, and established spirometric normal values for an altitude of 3,100m for white men.
American Review of Respiratory Disease, June 1978, Vol.118, No.6, p.1055-1058. Illus. 14 ref.

1977

CIS 78-1180 Mambetaliev B.
Indices for evaluation of working capacity of miners according to altitude
Nekotorye pokazateli rabotosposobnosti u gornorabočih na različnyh vysotah [in Russian]
Results of ergometric and other studies in 44 and 43 miners working respectively at low (860m) and high altitudes (2,800m) in the Tsian'-Shan mountains (USSR). Maximal aerobic power was relatively poor in the high-altitude workers. Studies of functional parameters of mental stress caused by arduous work in difficult climatic conditions showed the cardiovascular and respiratory systems of high-altitude miners to be under very much greater stress than in those working at low altitudes. These differences must be taken into account when organising mining work on a scientific basis.
Gigiena i sanitarija, Aug. 1977, No.8, p.35-40. 14 ref.

1976

CIS 78-1135 Böni M., Schibli R., Nussberger P., Bühlmann A.A.
Diving at diminished atmospheric pressure: Air decompression tables for different altitudes.
The rationale of the tables and the studies that led up to them (106 simulated dives and 278 actual dives at 900-1,700m altitude) are described. The schedules themselves are decompression tables, maximum ascent-rate tables, surface-interval tables and repetitive timetables, for altitudes up to 3,200. Schedules up to 2,000m were tested in humans under wet conditions; some are untested.
Undersea Biomedical Research, Sep. 1976, Vol.3, No.3, p.189-204. 5 ref.

CIS 76-1259 Treaftis H.N., Tomb T.F., Carden H.F.
Effect of altitude on personal respirable dust sampler calibration.
Studies on the effect of altitude on 3 personal samplers (MSA Model G, Bendix 3900 and Bendix C115) performed in a vacuum chamber simulating altitudes of 800-16,000 feet (240-4,800m) are described. Pump performance and calibration of the flow-rate meters were both affected by altitude changes. In all 3 cases, the flow rate of a pump unit calibrated for 2l/min at 800 feet increased by approx. 5% at 12,000 feet if not adjusted. If at 12,000 feet the flow was adjusted so that the flow-rate meter float was at the original calibration mark, flow rate increased by 10-23%. Equations for the empirical relations so derived are given for each sampler.
American Industrial Hygiene Association Journal, Mar. 1976, Vol.37, No.3, p.133-138. Illus. 6 ref.

1974

CIS 75-776 Thierfeldt P.
Risks of traumatic incidents in simulated low-pressure ascents in decompression chamber, their prevention and treatment
Zwischenfälle bei Unterdruckkammeraufstiegen, deren Vorbeugung und Behandlung [in German]
The author considers the possibilities of decompression-chamber accidents due to lack of oxygen, low pressure or variations in air pressure. Barotrauma of ear and nasal sinuses, observed in 10% of the cases examined, is the most frequent accident, followed by pre-collapse and collapse due to hypoxia, decompression disturbances and altitude meteorism at heights between 10,000 and 12,000m. Reference is made to the possibility of aero-odontalgia, hypocapnia and vomiting into the respirator. Prevention and treatment. Importance of psychological aspects when conducting simulated ascent tests and necessity for employing experienced personnel for this purpose.
Verkehrsmedizin und ihre Grenzgebiete, 1974, Vol.21, No.7, p.230-236.

1973

CIS 75-878 Ringenbach G.
Haematological adjustment to high altitudes
L'acclimatation hématologique à l'altitude. [in French]
After a review of past and current knowledge concerning altitude polyglobulia or long-term polyglobulia, that is, the true haematological adjustment to altitude, the author summarises 20 years of personal research on the phenomena which lead to this adaptation. He used a veino-capillary coupled erythrogram technique on 72 subjects who had to remain for long periods at high altitudes on account of their occupation. He observed a reduction of red blood cells in the venous blood, and an unequal distribution of these cells in both venous blood and capillary blood. Based on these observations, he derived a chronology of adaptation and conducted a pathogenic study from which he concluded that there was pertubation of the water metabolism. He suggests prophylaxis by administration of haematoporphyrin to enable workers to live safely and comfortably at high altitudes.
Revue de médecine aéronautique et spatiale, 4th quarter 1973, Vol.12, No.48, p.595-600. 19 ref.