I have never liked the results of a Saccomanno's fixed CSF prep. It
further dilutes what is usually a very dilute specimen anyway. I feel
that a cytospin should be done from the neat specimen if possible, and
always as a stat. We do use the hematology cell count to aid in
dilution/concentration decisions. Left over (or held over) specimens will
maintain their morphology quite nicely for up to 24hrs at 4'C.  Also, we
add one drop (100 microliters) of 22% bovine serum albumin (coats and
protects cells from excessive drying, aids in blocking for immunos) to
the Cytospin sample chamber after loading the CSF.  Spin at 1200 rpm
with LOW acceleration for 5min then fix immediately in 95%ETOH for
10min before pap stain or 20min before immunos.  

Since saccomanno's coagulates proteins, it can mucky up cell surface
antigen markers that you may want to perform. Example: Kappa and
Lambda on a CSF demonstrating a lymphoma. By using the neat
specimen, we avoided labeling all the Kappa and Lambda present in the
fluid and labeled crisp, clear stain on the cell surface only. Not
coagulated lumps of protein that would have lit up in a saccommano's
prep. 
Just my 2 cents.
Terri Braud, Hist. Supv.
St Frances Cabrini Hospital
Alexandria, LA