EFFECTS OF ACUTE HYPOXIA ON HEMODYNAMICS IN DOGS
Abstract
Background: Almost 50 years ago tire proposition that acute hypoxia elicits pulmonary vasoconstriction was made.By now methods have been standardised for exploring the pulmonary and systemic circulation in a systematic &sophisticated way and tire introduction of cardiac catheterization had brought the previous remote pulmonarycirculation within reach. Methods: This study was designed to see the effects of acute hypoxia on hemodynamics withthe advanced, sophisticated equipment and standardised method. The effects of acute 10 minutes’ hypoxia werestudied on hemodynamics in anaesthetized dogs. Results: Acute hypoxia increased the Cardiac Output from 1.76 ±0.43 to 1.91 ± 0.52 L/min. HR from 240 ± 55.58 to 260 ± 63.34 beat/min, Ppa from 2.24 ± 0.61 to 3.39 ± 1.09 kPa,PVR from 9.49 ± 3.33 to 14.30 ± 5.29 kPa. s/L, Psa from 14.53 ± 1.16 to 15.16 ± 1.17 kPa. SVR from 61.50 ± 14.81to 64.33 ± 15.02 kPa. s/L and CBF from i73.62 ± 81.99 to 192.50 ± 85.40 ml/min, respectively. Conclusions: Theresults showed that Acute hypoxia increased all the parameters but the increase in pulmonary vascular resistance wasmore significant than systemic vascular resistance. This shows that in vivo the hypoxic response of cerebral vessel isdilative, while the hypoxic response of pulmonary vessels as well as that of peripheral systemic vessel is constrictive.Key Words: Hypoxia, Hemodynamics.References
Von Euler. Liljestrand G: Observation of Pulmonary arterial
blood pressure in cat. Acta Physiol Scand 12:301-320,1946.
Duke HN: The pulmonary circulation. In the control of the
circulation of blood, edited by RJS McDouall. London,
Dawson and sons, 1956, pp 144-162.
Liljestrand G: Chemical control of distribution of pulmonary
blood flow. Acta Physiol Scand 44: 216-240,1958.
Fishman AP: Respiratory gases in the regulation of
pulmonary circulation. Physiol Rev 41: 214-280:1958
Fishman AP: Dynamics of pulmonary circulation, in
handbook of physiology, section 2, circulation, vol 2, edited
by WF Hamilton, P Dow. Washington D.C, American
Physiological Society, 1963. pp 1667-1743.
Jin X R, Fan M, Wang Z Q et al. Strain difference in
pulmonary vascular responsiveness to hypoxia in rats. J Tongji
Med Univ, 1990. 10(3): 134 Rowell L B, Blackmon J R.
Review article, Human
cardiovascular adjustment to acute hypoxaemia. Clinical
Physiol, 1987,7:349
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