[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re[2]: incontinent patient dosed with ~100 mCi of I-131
I will be out of the office from June 20 through July 4, returning July 5th.
Please contact Jennifer Smulling on x2978 if you need imediate assistance.
___________________________________________________________________________
Subject: RE: incontinent patient dosed with ~100 mCi of I-131
From: radsafe@romulus.ehs.uiuc.edu
Date: 06/19/00 17:20:37
I assume your patient has thyroid cancer, has undergone a sub-total
thyroidectomy and you are treating her with 100 mCi (2.7 GBq or 2700 MBq) of
I-131 to ablate post-surgical thyroid tissue remnants, or you are treating
post-thyroidectomy metastatic disease. In this case, you would expect the
patient to excrete >95% of the administered activity, primarily through the
urine. I would have a great deal of concern about potential deterministic
radiation effects to the skin of the buttocks and genitals of this patient.
NCRP Report #111 "Developing Radiation Emergency Plans for Academic, Medical
or Industrial Facilities" table 4.3 gives a skin contamination dose
equivalent for I-131 of 1694 mSv per square centimetre per MBq per hour.
During the first night after oral administration of the radioactivity, it
would not be unusual for the patient to void 10% of the activity, which
would be trapped over a surface area in her diaper of about 100 cm^2.
Assuming the patient sleeps 8 hours with 10 mCi (370 MBq) or more of
excreted I-131 in her diaper (direct contact with her skin), she could
theoretically receive a skin dose of 50 Sv per cm^2 - which could lead to a
spectrum of nasty skin effects, including erythema, moist desquamation,
total breakdown. The threshold dose for moist desquamation is 15 Sv. And
that's just the skin dose for the first night. The skin in that area is
already fragile and vulnerable to breakdown because of constant exposure to
ammonia in the urine - have you ever seen a baby with diaper rash?? Very
nasty and long-term effects for the patient, plus high potential for a
successful medical malpractice suit against the physican and medical
institution.
If this were our patient, I would strongly recommend hospitalizing the
patient for at least 48 hours so that she could be catheterised with the
shielded "hot" urine collection bag emptied to the toilet every few hours by
trained nursing staff. I would make sure the patient is very well-hydrated
(I.V. drip) and/or lots of liquid orally to flush out of her system the
radioactivity not taken up by the target tissue As a matter of fact, I have
done this for an incontinent patient in diapers being treated for Graves
disease with much less activity - when we expected only about 5 mCi excreted
via the urine.
Regards,
Karin
Gordon**********************************************************************
**
*****************
Karin Gordon RTR, RTNM, RTT
Radiation Safety Coordinator
Winnipeg Regional Health Authority
Health Sciences Centre
GC-214, 820 Sherbrook Street
Winnipeg, Manitoba
CANADA, R3A 1R9
phone (204) 787-2903
fax (204) 787-1313
e-mail kgordon@hsc.mb.ca
************************************************************************
*****************
Message-----
From: Douglas Simpkin [mailto:dsimpkin@execpc.com]
Sent: Monday, June 19, 2000 12:37 PM
To: Multiple recipients of list
Subject: incontinent patient dosed with ~100 mCi of I-131
Folks:
Ignorant question time!
Our nuclear medicine physicians are talking about treating an incontinent
patient with ~100 mCi of I-131. Even if we hold her (and her diapers) in
the hospital for a few days, she'll still be generating I-131 waste once
she gets home.
How would others handling this?
1. Ignore waste she generates at home, and hope the landfill doesn't
monitor.
2. Have her collect her own waste for decay in her basement?
3. Have her collect her own waste, and we then pick up the trash for
decay-in-storage here. What are the DOT repercussions of me having a
trunk-full of hot Depends?
Any comments?
Thanks,
Doug
Douglas J. Simpkin, Ph.D., D.A.B.R.
St. Luke's Medical Center
2900 West Oklahoma Avenue
Milwaukee, WI 53215
phone: (414)649-6457
fax: (414)649-5118
email: dsimpkin@execpc.com
************************************************************************
The RADSAFE Frequently Asked Questions list, archives and subscription
information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html
************************************************************************
The RADSAFE Frequently Asked Questions list, archives and subscription
information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html
************************************************************************
The RADSAFE Frequently Asked Questions list, archives and subscription
information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html