Re: I-131 Therapy and Contamination

[Betty Schwab <bschwab@hsc.vcu.edu>]

    We usually cover the hospital room floor with Chux and tape them
down so the patient won't trip.  We mold aluminum foil over the toilet
and rails in the bathroom (looks like a silver throne) and tape plastic
bags over the phone and nurse call control so the patient can see the
buttons through the plastic.  We also put Chux on the mattress under the
sheets and have the nurses order disposable eating trays and utensils.
The bathrooms in our hospital have ceramic tile with grout and this can
be very hard to decontaminate.  So we make sure the bathroom floor is
well covered.  Linoleum tile is easier to decontaminate.
    I've been involved with I-131 therapies up to 520 mCi.  Since these
patients no thyroid gland and are being treated for thyroid metastases,
they usually have an uptake of less than 5%.  This means almost the
entire dose will be excreted or secreted by the patient.  With therapies
above 300 or 400 mCi, we've noticed that room clearance is usually not
possible for a couple of days after the patient is discharged.  The
entire room is "hot" including everything under the protective paper.
It's impossible to find discrete areas that need to be decontaminated.
In these cases, we close the room for a couple of days, then are able to
go in and decontaminate the room.
    We have the patient assigned to a room at the end of a corridor and
vacate the patient room next door until exposure levels are acceptable
there. In these cases the I-131 therapy patients weren't messy (we've
had those, too).  It's almost as if the excreted I-131 volatilizes and
"plates out" in the room.  Anyone else notice this with high I-131
doses?