Examination of the cerebrospinal fluid is frequently a crucial point in diagnosis. If a "bloody tap" is encountered, however, the fluid is usually discarded as valueless. The resultant delay in diagnosis is always disturbing and may become a serious matter in the presence of an acute illness.
Bauckus and Foord,1 Lange2 and, more recently, Gordon3 stated that even small quantities of blood vitiate the value of the examination of the cerebrospinal fluid. Levinson4 advised waiting three days before repeating a puncture when traumatic blood is present. The literature, moreover, gives few quantitative data concerning the effect of contaminating blood on the composition of the cerebrospinal fluid.
It has been our experience over a period of years that much valuable information can be obtained from examination of a bloody spinal fluid, provided certain precautions are observed. In most instances sufficiently accurate information can be obtained from a
SOLOMON P, DAILEY ME, FREMONT-SMITH F. CONTAMINATION OF THE CEREBROSPINAL FLUID BY BLOOD. Arch NeurPsych. 1934;31(6):1222-1234. doi:10.1001/archneurpsyc.1934.02250060108007