TY - JOUR
T1 - Pulmonary blood flow regulation
T2 - Influence of positive pressure ventilation
AU - Theissen, J. L.
AU - Fischer, S. R.
AU - Traber, L. D.
AU - Traber, D. L.
N1 - Funding Information:
This project was supported in part by Grant GM33324 from the National Institute of General Medical Sciences and SNA15845 from the Shriners of North America.
PY - 1995/12
Y1 - 1995/12
N2 - Positive pressure ventilation with PEEP has been reported to reduce hypoxic pulmonary vasoconstriction (HPV) and thus increase venous admixture. This effect was investigated in six chronically instrumented unanesthetized healthy sheep. The change in left pulmonary arterial blood flow (Q̇lpa, ultrasonic transit time) in response to unilateral lung hypoxia (10 min of N2 alternately to the left (LLH) and right lung (RLH)) was evaluated during mechanical ventilation with and without PEEP of 10 cm H2O in comparison to spontaneous breathing. In the spontaneously breathing animal and during mechanical ventilation without PEEP, Q̇lpa decreased during LLH from 30% to 16% of cardiac index, during RLH it increased to 51%. With 10 cm H2O of PEEP, Q̇lpa showed an identical reaction to hypoxia both in the left and right lung. It is concluded that mechanical ventilation and PEEP up to 10 cm H2O does not interfere with pulmonary blood flow regulation to hypoxia.
AB - Positive pressure ventilation with PEEP has been reported to reduce hypoxic pulmonary vasoconstriction (HPV) and thus increase venous admixture. This effect was investigated in six chronically instrumented unanesthetized healthy sheep. The change in left pulmonary arterial blood flow (Q̇lpa, ultrasonic transit time) in response to unilateral lung hypoxia (10 min of N2 alternately to the left (LLH) and right lung (RLH)) was evaluated during mechanical ventilation with and without PEEP of 10 cm H2O in comparison to spontaneous breathing. In the spontaneously breathing animal and during mechanical ventilation without PEEP, Q̇lpa decreased during LLH from 30% to 16% of cardiac index, during RLH it increased to 51%. With 10 cm H2O of PEEP, Q̇lpa showed an identical reaction to hypoxia both in the left and right lung. It is concluded that mechanical ventilation and PEEP up to 10 cm H2O does not interfere with pulmonary blood flow regulation to hypoxia.
KW - Blood flow, pulmonary artery
KW - Hypoxia, pulmonary vasoconstriction
KW - Hypoxic pulmonary vasoconstriction
KW - Mammals, sheep
KW - PEEP
KW - Positive pressure ventilation
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U2 - 10.1016/0034-5687(95)00049-6
DO - 10.1016/0034-5687(95)00049-6
M3 - Article
C2 - 8904016
AN - SCOPUS:0029561098
SN - 0034-5687
VL - 102
SP - 251
EP - 260
JO - Respiration Physiology
JF - Respiration Physiology
IS - 2-3
ER -