Accurate measurement of cerebral metabolism in the conscious, unrestrained neonatal piglet. I. Blood flow.

A technique has been developed for the accurate and precise measurement of cerebral blood flow in the conscious, unrestrained neonatal piglet. Repeat determinations under conditions in which the animals could observe the experimenters showed that there was a significant fall in cerebral perfusion rate between first and second measurement, amounting to about 15 ml/min/100g. This systematic error was subsequently avoided by use of screens and the reproducibility of the technique was then estimated to be 5.9 ml/min/100 g (SD). When 5 animals were subjected to moderate stress by handling, there was a significant (p less than 0.001) increase in cerebral perfusion rate to a mean value of 172.6 +/- 35.0 ml/min/100g (+/- SEM). Mean resting cerebral perfusion rate in 18 normal animals was 65.6 +/- 4.6 ml/min/100 g (+/- SEM), which is similar to that reported in the conscious neonates of other species including man.