Effect of regional hypoxia on the distribution of pulmonary blood flow in man.
نویسندگان
چکیده
• The observation that hypoxia causes an elevation of pulmonary arterial pressure probably secondary to pulmonary vasoconstriction led von Euler and Liljestrand to suggest that local pulmonary hypoxia might play a role in controlling the distribution of pulmonary blood flow. One method of studying this proposed mechanism in man has been to induce unilateral hypoxia by means of a bronchospirometry catheter. Fishman et al. gave 10% oxygen in nitrogen to one lung and failed to find a response. However, Himmelstein et al. found approximately a 40% decrease in pulmonary blood flow to the hypoxic lung in three out of five subjects when 5% oxygen was administered. A fourth subject had an increased pulmonary artery pressure but no change in the partition of the pulmonary blood flow. The results on the fifth subject were inconclusive. In contrast, Defares et a!. found approximately a 44% decrease in blood flow to the lung breathing 10% oxygen in 10 normal subjects. Fishman' has reviewed the studies of unilateral hypoxia in man and concludes that the bulk of evidence suggests an increased resistance to perfusion on the hypoxic side probably secondary to ipsilateral vasoconstriction. Cautious interpretation of the experimental findings has been necessary since conclusions regarding pulmonary vasoconstriction have been based on the finding of an increase in pulmonary vascular resistance or a greater
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ورودعنوان ژورنال:
- Circulation research
دوره 18 5 شماره
صفحات -
تاریخ انتشار 1966