RE: incontinent patient dosed with ~100 mCi of I-131

[David W Lee <lee_david_w@lanl.gov>]

RADSAFERS:

Stupid question #3 or #4 so far on this thread.  If this incontinent
patient's attending physicians already agree/know that the patient is
incontinent, what is so difficult about catheterizing the patient and
collecting the radioactive urine in a bag/bottle which could then be
periodically poured down the hospital commode by a hospital radiological
control technician supporting this operation?

Best regards  David W. Lee, Radiological Engineering Team Leader,
Los Alamos National Laboratory (lee_david_w@lanl.gov), PH: (505)
667-8085; FAX:  (505) 667-9726




At 03:23 PM 06/19/2000 -0500, you wrote:
>  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
>
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DAVID W. LEE, CHP
Los Alamos National Laboratory
Radiation Protection Services
Radiological Engineering Team Leader
ESH-12, MS K483
Los Alamos, NM  87545
PH:   (505) 667-8085
FAX:  (505) 667-9726
lee_david_w@lanl.gov