Abstract
Cerebral blood flow (CBF) was measured by133Xe clearance to determine whether there were any residual effects of cardiopulmonary bypass (CPB) on the CBF response to changes in arterial PCO2 or blood pressure in the early (3–8 hr) post-CPB period. During CPB, the nine patients studied were managed according to alpha-stat, temperature uncorrected, pH management. The mean ± SD increase in CBF resulting from an increase in PaCO2 (1.35 ± 0.5 ml · 100 g−1 · min−1 · mmHg−1 PaCO2) was within the normal range, indicating appropriate CBF response to a change in PaCO2. There were no significant differences in CBF, being 25.7 ml · 100 g−1 · min−1 at a mean arterial blood pressure of 70 mmHg and 26.5 ml. 100 g−1 · min−1 at 110 mmHg, demonstrating intact cerebral autoregulation over this pressure range. We conclude that cerebral autoregulation and CO2 responsiveness are preserved in the immediate postoperative period after CPB using alpha-stat pH management.
Résumé
Le flot sanguin cérébral (CBF) a été mesuré par Xe133 afin de déterminer les effets résiduels de la circulation extracorporelle (CPB) sur les réponses due CBF aux changements de la PCO2 ou de la pression artérielle dans la période précoce en post CPB (3–8 hres). Durant le CPB, les neuf patients étudiés et chez qui le pH ne fut pas corrigé selon la température, l’augmentation moyenne ± SD de la CBF après une augmentation de la PaCO2 (1,35 ± 0,5 ml · 100 gm−1 · min−1 mmHg−1 PaCO2) était à l’intérieur des normes indiquant une réponse appropriée du CBF au changement de la PaCO2. Il n’y avail aucune différence significative dans le CBF, étant 25,7 ml · 100 g−1 · min−1 pour des pressions artérielles moyennes de 70 mmHg et 26,5 ml · 100 g−1min−1 à 110 mmHg, démontrant une autorégulation cérébrale intacte pour cet écart de pression. On conclut que l’autorégulation cérébrale et la réponse au CO2 est préservée dans la période postopératoire immédiate après CPB utilisant la conduite alpha-stat du pH.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Shaw PJ, Bates D, Cartlidge NEF, Heaviside D, Julian DG, Shaw DA. Early neurologic complications of coronary artery bypass surgery. Br Med J 1985; 291: 1384–7.
Smith PLC, Treasure T, Newman SP et al. Cerebral consequences of cardiopulmonary bypass. Lancet 1986; i:823–5.
Breuer AC, Furlan AJ, Hanson MR et al. Central nervous system complications of coronary artery bypass graft surgery: prospective analysis of 421 patients. Stroke 1983; 14: 682–7.
Henriksen L. Evidence suggestive of diffuse brain damage following cardiac operations. Lancet 1984; i: 816–20.
Murkin JM, Farrar JK, Tweed WA, McKenzie FN, Guiraudon G. Cerebral autoregulation and flow/ metabolism coupling during cardiopulmonary bypass: the influence of PaCO2. Anesth Analg 1987; 66: 825–3.
Irish CL, Murkin JM, Guiraudon GM. Anaesthetic management for surgical cryoablation of accessory conducting pathways: a review and report of 181 cases. Can J Anaesth 1988; 35: 634–40.
Murkin JM. Appendix: CBF methodology.In: Hilberman M (Ed.). Brain Injury and Protection During Heart Surgery. Boston: Martinus Nijhoff Publishing, 1988: 61–6.
Hoedt-Rasmussen K, Sveinsdoftir E, Lassen NA. Regional cerebral blood flow in man determined by intra-arterial injection of radioactive inert gas. Circ Res 1966; 18: 237–47.
Obrist WD, Wilkinson WE. Stability and sensitivity of CBF indices of the noninvasive133Xe method.In: Hartman A, Hoyer S (Eds.). Cerebral Blood Flow and Metabolism Measurement. New York: Springer-Verlag 1985: 30–6.
Chen RYZ, Fan FC, Kim S, Jan KM, Usami S, Chien S. Tissue-blood partition coefficient for xenon: temperature and hematocrit dependence. J Appl Physiol 1980; 49: 178–83.
Grubb RL, Raichle ME, Eichling JO, Ter-Pogossian MM. The effects of changes in PaCO2 on cerebral blood volume. Stroke 1974; 5: 630–4.
Prough DS, Stump DA, Roy RCet al. Response of cerebral blood flow to changes in carbon dioxide tension during hypothermic cardiopulmonary bypass. Anesthesiology 1986; 64: 576–81.
Cold GE, Christensen KJS, Nordentoft J, Engberg M, Pedersen MB. Cerebral blood flow, cerebral metabolic rate of oxygen and relative CO2 reactivity during neuroleptanaesthesia in patients subjected to craniotomy for supratentorial cerebral tumours. Acta Anaesthesiol Scand 1988; 32: 310–5.
Kety SS, Schmidt DF. The effects of altered arterial tensions of carbon dioxide and oxygen on cerebral blood flow and cerebral oxygen consumption of normal young men. J Clin Invest 1948, 27: 484–92.
Kety SS, Schmidt CF. The effects of active and passive hyperventilation on cerebral blood flow, cerebral oxygen consumption, cardiac output, and blood pressure of normal young men. J Clin Invest 1946; 25: 197–219.
Wollman H, Smith TC, Stephen GW et al. Effects of extremes of respiratory and metabolic alkalosis on cerebral blood flow in man. J Appl Physiol 1968; 24: 60–5.
Grubb RL, Raichle ME. Effects of hemorrhagic and pharmacologic hypotension on cerebral oxygen utilization and blood flow. Anesthesiology 1982; 56: 3–8.
Wang HH, Liv LMP, Katz RL. A comparison of the cardiovascular effects of sodium nitroprusside and trimethaphan. Anesthesiology 1977; 46: 40–8.
Moyer JH, Morris G, Snyder H. A comparison of the cerebral hemodynamic response to aramine and norepinephrine in the normotensivc and hypotensive subjects. Circulation 1954; 10: 265–70.
Mutch WAC, Louise AM, Ringaert KRA. Phenylephrine increases regional cerebral blood flow following hemorrhage during isoflurane-oxygen anesthesia. Anesthesiology 1989; 70: 276–9.
Greenfield JC, Tindall GT. Studies of the effects of vasopressor drugs on internal carotid blood flow in man.In: Bain WH, Harper AM (Eds.). Blood Flow Through Organs and Tissues, Edinburgh: Livingstone, 1968; 336–48.
Weil-Malherbe H, Axelrod H, Tomchick K. Blood-brain barrier for adrenaline. Science 1958; 129: 1226–7.
Mackenzie ET, McCulloch J, O’Kean M, Pickard JD, Harper AM. Cerebral circulation and norepinephrine: relevance of the blood-brain barrier. Am J Physiol 1976; 231: 483–8.
Newberg LA, Milde JH, Michenfelder JD. The cerebral metabolic effects of isoflurane at and above concentrations that suppress cortical electrical activity. Anesthesiology 1983; 59: 23–8.
Vernhiet J, Renou AM, Orgogozo JM, Constant P, Caille JM. Effects of a diazepam-fentanyl mixture on cerebral blood flow and oxygen consumption in man. Br J Anaesth 1978; 50: 165–9.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
McNeill, B.R., Murkin, J.M., Farrar, J.K. et al. Autoregulation and the CO2 responsiveness of cerebral blood flow after cardiopulmonary bypass. Can J Anaesth 37, 313–317 (1990). https://doi.org/10.1007/BF03005581
Issue Date:
DOI: https://doi.org/10.1007/BF03005581