Acute Oxygen Toxicity Research Articles

Positive airway pressure in lambs spontaneously breathing air and oxygen

The effects of 10 cm H 2O positive endexpiratory pressure (PEEP) were studied in 26 unrestrained Hampshire and Corriedale lambs, breathing spontaneously air or pure oxygen. No changes in lung morphology, pulmonary mechanics or arterial blood gas tensions were detected after air breathing with 10 cm H 2O PEEP for one week. No changes were found in mean pulmonary artery pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance or cardiac output in oxygen breathing lambs until minutes before death. Addition of PEEP to oxygen breathing accelerated the development of respiratory acidemia and death (PEEP group mean lifespan 54 3 4 hr, without PEEP mean lifespan 71 3 4 hr). Morphologic changes of acute oxygen toxicity were present in oxygen breathing lambs and lung water was increased. Oxygen breathing lambs died from apnea with hypercarbia and a markedly increased ( A-a) DO 2. An increase in pulmonary vascular resistance or right ventricular failure do not appear to be major factors in the syndrome of fulminant acute respiratory insufficiency due to oxygen toxicity in lambs.

Relative susceptibility of altitude-acclimatized mice to acute oxygen toxicity

The influence of hypoxic acclimatization at altitudes of 0, 5,000, or 15,000 ft on the relative susceptibility to acute oxygen poisoning was determined in 288 adult female mice. After acclimatization periods of 1, 2, 4, or 8 wk, the mice were exposed to oxygen at high pressures (OHP) of 4, 6, or 9 ATA and the times to convulsion and death recorded. A factorial analysis of variance indicated that altitude and OHP level had inverse, log-linear effects on both parameters. The duration of acclimatization progressively decreased the time to death. The onset of convulsions and death was independent of body weight. There were significant interactions on the measured parameters between various combinations of altitude, OHP level, and duration of acclimatization. While alterations in the metabolism of gamma-aminobutyric acid and high-energy compounds are common to both hypoxia and hyperoxia, the most plausible explanation of the results relates to the decrease in buffer base induced by hypoxic acclimatization which might have caused CO2 potentiation of OHP symptoms.

Radiological manifestations in patients on continuous positive-pressure breathing.

Chest films of patients on continuous positive-pressure breathing (CPPB) occasionally prove difficult to interpret. Diaphragmatic paralysis may be masked, and lobar atelectasis may present with confusing findings. If the radiologist is not aware that the patient is receiving CPPB, two other findings may be confusing: (a) hyperinflation of the lungs and (b) unusually rapid clearing of pulmonary edema, atelectasis, or both. Complications of CPPB include acute gastric dilatation, oxygen toxicity, pneumothorax, pneumomediastinum, and pulmonary interstitial emphysema. In some cases, prolonged intubation may result in tracheal stenosis and/or malacia.

Acute pulmonary oxygen toxicity in spontaneously breathing anesthetized dogs.

ARTICLESAcute pulmonary oxygen toxicity in spontaneously breathing anesthetized dogsGM Clarke, G Smith, AT Sandison, and IM LedinghamGM Clarke, G Smith, AT Sandison, and IM LedinghamPublished Online:01 Feb 1973https://doi.org/10.1152/ajplegacy.1973.224.2.248MoreSectionsPDF (2 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByReducing the oxygen concentration of gases delivered from anaesthetic machines unadapted for medical air22 August 2011 | Veterinary Record, Vol. 169, No. 17Oxygen toxicityPharmacology & Therapeutics. Part B: General and Systematic Pharmacology, Vol. 1, No. 4 More from this issue > Volume 224Issue 2February 1973Pages 248-255 Copyright & PermissionsCopyright © 1973 by American Physiological Societyhttps://doi.org/10.1152/ajplegacy.1973.224.2.248PubMed4686480History Published online 1 February 1973 Published in print 1 February 1973 Metrics

Selective vulnerability of the central nervous system to hyperbaric oxygen.

The adverse effects of hyperoxia on the central nervous system (CNS) have been well known since the 19th century writing of Paul Bert. Acute CNS oxygen toxicity is manisfested by grand mal convulsions and may result in death following status epilepticus. Bean and Seigfried2 reported a delayed or chronic type of oxygen poisoning in rats subjected to repeated brief intermittent exposures to hyperbaric oxygen (HO), which resulted in permanent limb paralysis. The paralyses observed in this type of oxygen toxicity usually affect the forelimbs bilaterally with the animals assuming a kangaroolike posture. Rigidity of the paralyzed limbs is common. Animals capable of locomotion are ataxic. A few rats become quadriplegic.

Hyperbaric oxygen-induced seizure in a marine mammal, the seal.

ARTICLESHyperbaric oxygen-induced seizure in a marine mammal, the sealD Kerem, G Kooyman, JP Schroeder, JJ Wright, and CM DrabekD Kerem, G Kooyman, JP Schroeder, JJ Wright, and CM DrabekPublished Online:01 May 1972https://doi.org/10.1152/ajplegacy.1972.222.5.1322MoreSectionsPDF (812 KB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation More from this issue > Volume 222Issue 5May 1972Pages 1322-1325 Copyright & PermissionsCopyright © 1972 by American Physiological Societyhttps://doi.org/10.1152/ajplegacy.1972.222.5.1322PubMed5022390History Published online 1 May 1972 Published in print 1 May 1972 Metrics