title: Effects of Acute, Profound Hypoxia on Healthy Humans: Implications for Safety of Tests Evaluating Pulse Oximetry or Tissue Oximetry Performance.
abstract: Extended periods of oxygen deprivation can produce acidosis, inflammation, energy failure, cell stress, or cell death. However, brief profound hypoxia (here defined as SaO2 50%-70% for approximately 10 minutes) is not associated with cardiovascular compromise and is tolerated by healthy humans without apparent ill effects. In contrast, chronic hypoxia induces a suite of adaptations and stresses that can result in either increased tolerance of hypoxia or disease, as in adaptation to altitude or in the syndrome of chronic mountain sickness. In healthy humans, brief profound hypoxia produces increased minute ventilation and increased cardiac output, but little or no alteration in blood chemistry. Central nervous system effects of acute profound hypoxia include transiently decreased cognitive performance, based on alterations in attention brought about by interruptions of frontal/central cerebral connectivity. However, provided there is no decrease in cardiac output or ischemia, brief profound hypoxemia in healthy humans is well tolerated without evidence of acidosis or lasting cognitive impairment.
authors.affiliation: From the *Department of Anesthesia and Perioperative Care, University of California at San Francisco School of Medicine, San Francisco, California, †Clinimark Labs, Louisville, Colorado, and ‡Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina.
authors.forename: Philip E
authors.initials: PE
authors.lastname: Bickler
authors.forename: John R
authors.initials: JR
authors.lastname: Feiner
authors.forename: Michael S
authors.initials: MS
authors.lastname: Lipnick
authors.forename: Paul
authors.initials: P
authors.lastname: Batchelder
authors.forename: David B
authors.initials: DB
authors.lastname: MacLeod
authors.forename: John W
authors.initials: JW
authors.lastname: Severinghaus
mesh_terms: D000138:Acidosis / Q000209:etiology / Q000503:physiopathology; D000208:Acute Disease; D000222:Adaptation, Physiological; D000818:Animals; D001288:Attention; D015415:Biomarkers / Q000097:blood; D001921:Brain / Q000503:physiopathology; D002302:Cardiac Output; D003071:Cognition; D003072:Cognition Disorders / Q000209:etiology / Q000503:physiopathology / Q000523:psychology; D004195:Disease Models, Animal; D006801:Humans; D000860:Hypoxia / Q000097:blood / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D010092:Oximetry; D010100:Oxygen / Q000097:blood*; D011237:Predictive Value of Tests; D012123:Pulmonary Ventilation; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors
chemical_list: D015415:Biomarkers; D010100:Oxygen