Ventriculocisternal Perfusion Studies in the Monkey. II. PCO sub 2 and the Rate of Formation of Cerebrospinal Fluid

Abstract : Changes in cerebrospinal fluid formation rate (Vf) with hypocapnia and hypercapnia were measured by the ventriculocisternal perfusion technique in 24 rhesus monkeys anesthetized with nitrous oxide. In addition cerebral blood flow (CBF) was measured by the hydrogen clearance method. The results indicate that in the monkey variations of PCO2 within broad physiologic limits, which are sufficient to cause large changes in CBF, have little effect on Vf. This observation is of clinical importance in all respiratory disease states characterized by an elevated PCO2, and also is of very practical significance to surgeons and anesthesiologists who often wish to vary PCO2 at surgery.