[Histonet] Almost Eliminating Floaters

[Steve McClain]

MY APOLOGIES FOR NOT DELETING THE REST OF THE HISTONET EMAIL FROM MY
PRIOR RESPONSE.  I HAVE ADDED ADDITIONAL NOTES AT THE END.- STEVE
Floaters on the water bath are generally not the problem, are usually
identifiable, unlike the serious issue posed by floaters in the block.

I would suggest counting floaters to get a benchmark- ANY COUNT YOU MAKE
WILL PROBABLY BE AN UNDERESTIMATE, BUT AT LEAST YOU HAVE SOMETHING TO
TRACK..
In order to change the outcome, you (the institutional you) must change
what you are doing.
SO change your grossing-procedure.

Start by scrupulously cleaning every pair of forceps.

Keep an open vial of 50% alcohol at the bench to have the grossers rinse
their forceps between specimens.
Photograph every specimen-this forces the grossers to maintain a clean
background.  If you do not have grossing cameras, then mount a video
camera above the grossing station and let it run.  Point is a few hours
study of technique can help identify where the problem is. Better than
wasting many hours.

Have grossers begin to wrap every small specimen in lens paper- Three
darn good reasons.  Wrapping specimens with forceps helps to clean the
forceps before the next specimen.  At embedding , the action of
opening/unwrapping specimens with forceps cleans forceps at the
embedding center. Floaters can also occur during processing-wrapping
specimens prevents floaters during processing and keeps processors
clean.  
(If you don't believe me- filter your first reagent when changing and
then process that to a block- I once inherited a processor from a lab
that did placentas.  We found pieces of placenta in our derm specimens
as long as 5 or 6 months later.)

Change fixative and clean block bucket at the grossing bench routinely.
You may wish to consider rinsing all blocks in fresh reagent BEFORE
placing on processor.

Evolving to this procedure, the floaters fell to 1 per 15,000, about 3
per year in our small lab.

ADDITIONAL NOTES:
Focusing on grossing is neither putting all your eggs in one basket nor
blaming the grossers.  

Focusing on grossing floaters is focusing on the complex,  dirty
workplace where historically the vast majority (70-80-90%) of these
errors are generated.
The people may be part of the problem, yet the system is at the heart of
the issue and determines the error-rate.

The system is complicated, but includes the environment and structure
and policy.
There is too much going on at or near the grossing bench, make it quiet
and simple, reduce  distractions
There are generally more grossers than embedders and greater variation
in technique and sample size-(embedders generally only have to deal with
samples 15x15mm or less.)
And greater numbers of reagents and fixatives 
And perhaps even a cryostat for FS
Or FAXITRON. 
Or a computer
Accessioning, scanning documents and cassette printing
Maybe a telephone.
Or a reagent recycler 
Or a processor
(eliminate as many distractions as you can.  Separate quiet enclosed
areas where specimens can be controlled and studied without distraction.
For example we banned cellphones from the grossing area).
Point is simplify and reduce noise.
Make the grossing area for small specimens quiet.
The singularly important reason we never adopted voice recognition in
the grossing area  had to do with the distractions imposed by messing
with computers, the noise of talking into a machine, the distraction of
looking at a screen to proofread while working with a one of a kind
valuable specimen in the most error-prone area of the lab. 
Talking and looking at a computer screen is neither studying tissue nor
professional.
If you use that type of system, consider modifying your procedure to
focus on getting the tissue cleanly in the block and the block safely in
reagent, then do the dictation.
Some of our grossers were resistant to change with valid reasons for
doing so we let them be the baseline control- when we wanted to make a
change we compared method A to method B.
When one method was statistically better we showed them the data. 
There is room for the inevitable disagreement- but study and get some
data and restudy if needed.

Personally, I want to see grosser focused on the tissue, studying tissue
as a trained professional; 
Once the tissue is safely in the cassette and in the next reagent (or
fixative or ) then the grossers enter their own data.
Scan the next bottle barcode and move on to the next specimen.

'Clean' is a relative term and a perceptual problem. (What is
clean?-even when your grossing area is spotless-if one were to eat in
the lab would you prefer to do so standing next to the grosser or the
embedder? Not suggesting it is permitted- just which area is cleaner and
what is meant by clean)
SUGGESTIONS
Have an EM (electron microscope) tech come in and get it clean to
his/her satisfaction.  They are used to clean-room mentality and
standards
Grossers are reluctant to change paper towels or other cutting surfaces
or cutting tools between specimens.
Make them freely available.
Make the grossing benches spotless.
Make the reagent buckets, spotless. 
Fresh reagents every shift- or whenever a speck appears.
The instruments, spotless.
Cut white or blue flat paper towels into 2.5x2.5 inch squares and gross
on them- fewer floaters than brown C-fold towels or use pink dental wax
sheets.
Make a hard and fast rule about the number of tissue fragments per
cassette, e.g., 5- not more.
5 pieces in a cassette can be seen and verified easily. 
Place similar sized pieces in cassettes (if there are 10 pieces, 5 each
1mm and 5 each 3mm- all the 1mm go into one cassette and all the 3 mm in
the other cassette.  A 1mm speck-floater is not obvious among 3mm
pieces.  A sixth 1mm speck in the 1mm cassette is noticeable.
Use a separate area to gross large specimens and small biopsies, whether
on different benches or at different times of day than the small
biopsies.
ADVANTAGES OF PHOTOGRAPHY(if one photographs every specimen as we do at
McClain Labs
and critiques grossers for knifemarks or bloody stains on the towel or
leaving the same bloody background in consecutive photos by posting them
in the lab or at staff meetings, they soon catch on.  Rewards for great
photographs also sends a message. Photography is a great method for
verifying technique, for documenting your work, for )

METRICS- fewer is better.
Track floaters by grosser to see if you have an outlier or risk-taker.
Performance improves on any measured parameter when one follows through.
Historically grossing performance has been measured by how fast the
grosser completes x number of specimens.
That metric should be suspended or abandoned if there are issues in the
lab or you are working toward improving technique. 
FYI our other metrics are 1) lost specimens- (the number is zero in
seven years) 
And 2) cumulative blocks since last maintenance for each processor. 
3) catastrophic tissue loss- sounds a bit extreme, but means any hole or
tissue loss on the slide visible at low power (2x).  Each such slide is
photographed, investigated and discussed at staff meeting of grossers
and histotechs and pathologists.

PERSONNEL
Training histotechs to gross has a variety of benefits.
My good experience biases me -my best grossers have been histotechs
They respect the difficulty in embedding and cutting and communicate
well with other histotechs.
My second best are pathologists (I am the slowest) 
Physician assistants and residents are difficult (or maybe I demand too
much). Both operate largely outside traditional lab feedback loops.
(residents may be castigated by the attending who is legally responsible
for their mistakes at the microscope and feel discomfort, yet embedding
and cutting their mistakes at the microtome falls to the histotechs) I'd
rather gross myself than to clean up messes made by residents.
I was a jerk resident myself 1000 years ago- you know the trainee who is
told to keep the blocks postage stamp-size and brings in a commemorative
stamp?

Eliminating floaters is analogous to troubleshooting staining problems
where errors in technique in the early steps  cause great variation in
the final product.  Begin by eliminating early points of failure (for
staining-first care in handling prior to fixation, followed by prompt
fixation, adequate fixation,  then consistent thickness in grossing,
then processing, then cutting).   Errors in early steps cannot be fixed
later on.  Mashing tissue or prolonged drying or inadequate fixation
cannot be fixed by re-processing.  Once the floater is in the block, it
is there to stay and proof by testing the DNA of the floater and patient
is expensive, used to be $3000-$5000.

It is better and less expensive to eliminate these errors at the source.
Focusing on  grossing not only gets rid of the main source(s) of
variation, it also serves notice to the embedders once "grossing
floaters and "processing floaters" are eliminated embedding is next.

Steve A. McClain, MD
631 361 4000
NY BAD (MY bad from NY)
I apologize for replying with all the stuff still attached.