Title |
Supplementary oxygen for nonhypoxemic patients: O2 much of a good thing?
|
---|---|
Published in |
Critical Care, June 2011
|
DOI | 10.1186/cc10229 |
Pubmed ID | |
Authors |
Steve Iscoe, Richard Beasley, Joseph A Fisher |
Abstract |
Supplementary oxygen is routinely administered to patients, even those with adequate oxygen saturations, in the belief that it increases oxygen delivery. But oxygen delivery depends not just on arterial oxygen content but also on perfusion. It is not widely recognized that hyperoxia causes vasoconstriction, either directly or through hyperoxia-induced hypocapnia. If perfusion decreases more than arterial oxygen content increases during hyperoxia, then regional oxygen delivery decreases. This mechanism, and not (just) that attributed to reactive oxygen species, is likely to contribute to the worse outcomes in patients given high-concentration oxygen in the treatment of myocardial infarction, in postcardiac arrest, in stroke, in neonatal resuscitation and in the critically ill. The mechanism may also contribute to the increased risk of mortality in acute exacerbations of chronic obstructive pulmonary disease, in which worsening respiratory failure plays a predominant role. To avoid these effects, hyperoxia and hypocapnia should be avoided, with oxygen administered only to patients with evidence of hypoxemia and at a dose that relieves hypoxemia without causing hyperoxia. |
X Demographics
Geographical breakdown
Country | Count | As % |
---|---|---|
Canada | 9 | 29% |
Australia | 7 | 23% |
United States | 3 | 10% |
United Kingdom | 2 | 6% |
Korea, Republic of | 1 | 3% |
New Zealand | 1 | 3% |
Unknown | 8 | 26% |
Demographic breakdown
Type | Count | As % |
---|---|---|
Members of the public | 18 | 58% |
Scientists | 7 | 23% |
Practitioners (doctors, other healthcare professionals) | 4 | 13% |
Science communicators (journalists, bloggers, editors) | 2 | 6% |
Mendeley readers
Geographical breakdown
Country | Count | As % |
---|---|---|
Brazil | 2 | 2% |
Switzerland | 1 | <1% |
Austria | 1 | <1% |
Australia | 1 | <1% |
Germany | 1 | <1% |
South Africa | 1 | <1% |
Czechia | 1 | <1% |
Spain | 1 | <1% |
United States | 1 | <1% |
Other | 0 | 0% |
Unknown | 107 | 91% |
Demographic breakdown
Readers by professional status | Count | As % |
---|---|---|
Student > Ph. D. Student | 19 | 16% |
Student > Bachelor | 17 | 15% |
Other | 16 | 14% |
Researcher | 14 | 12% |
Professor > Associate Professor | 9 | 8% |
Other | 27 | 23% |
Unknown | 15 | 13% |
Readers by discipline | Count | As % |
---|---|---|
Medicine and Dentistry | 67 | 57% |
Nursing and Health Professions | 10 | 9% |
Agricultural and Biological Sciences | 8 | 7% |
Neuroscience | 4 | 3% |
Social Sciences | 3 | 3% |
Other | 8 | 7% |
Unknown | 17 | 15% |