rule of three


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rule of three

an arterial oxygen tension that is three times the value of the inspired oxygen concentration. It is regarded as an empiric guide to a temporarily acceptable minimal oxygenation or expression of clinical observation and has no scientific basis.
References in periodicals archive ?
While OPM has assured us that category rating is a better tool for ensuring veterans preference than the rule of three, we will monitor this to ensure that there are no unintended consequences.
I had a rule of three weeks at a time away and a cushion on both sides.
In the 1950s, the rule of three prevailed: Babies who were described with colic cried at least three hours, three days a week for three consecutive weeks.
I have two rules for pruning, my rule of two and my rule of three.
In a pediatric setting known to have a large number of abnormal size RBCs and a large number of hemoglobinopathies, we have found the Rule of Three to be a very useful tool.