Cisternal versus lumbar cerebrospinal fluid lactate concentration in healthy dogs

The analysis of cerebrospinal fluid biomarkers provides a wide range of information about the neurological health of a patient. Lactate is a metabolic precursor necessary for brain gluconeogenesis. When oxidative impairment or mitochondrial damage is present, lactate alteration occurs. The rostro-caudal dynamics of cerebrospinal biomarkers along the craniospinal axis in humans and horses was demonstrated in other studies. To the authors' knowledge, no clinical study has, so far, investigated the cerebrospinal fluid lactate concentration in dogs in association with the puncture site. The purpose of this study was to compare the cerebellomedullary cistern and lumbar cistern cerebrospinal fluid lactate concentrations in healthy dogs. Cerebellomedullary and lumbar cerebrospinal fluids were collected for the cell count, total protein determination and lactate analysis from ten healthy Beagle dogs. The results revealed a significantly increased lumbar cerebrospinal fluid lactate concentration when compared with the cerebellomedullary cistern level. The results included: the total nucleated cell count < 5 cells/µl, the red blood cell count < 500 cell/µl, the total proteins < 0.3 g/l, as well as the cerebellomedullary lactate values (1.44 ± 0.06 mM/l) and the lumbar cistern lactate values (1.58 ± 0.1 mM/l). The results of this study highlight useful data that help to understand the physiological lactate variations depending on the cerebrospinal fluid puncture site.