Biomedical Engineering Reference
In-Depth Information
ROUTINE TRAUMA
Initial
Surgery
Reparative
Surgery
Reconstructive
Surgery
1
2
5
10
50
100
DAYS AFTER INJURY
IRRADIATION PLUS TRAUMA
Initial
Surgery
Reparative
Surgery
Reconstructive
Surgery
Surgery Precluded
1
2
5
10
50
100
DAYS AFTER INJURY
Figure 5.4
Trauma timecourse.
radionuclides from the GI tract and removes some
radionuclides from the capillary bed surrounding
the intestine and prevents their reabsorption.
Prussian blue is effective in removing cesium,
thallium, and rubidium by the fecal route. It has
been used, without serious side effects, outside
the United States to treat humans for cesium
137 internal contamination. Main side effects are
nausea, vomiting, constipation and staining. Prus-
sian blue decreases the biological half-life of
cesium 137 to 30 per cent of the original 100
days. Prussian blue is approved as an investiga-
tional new drug; Radiation Emergency Assistance
Center/Training Site (REAC/TS) has the license
for research use.
If radioiodine (reactor accident) is considered,
prophylactic potassium iodide (Lugol's Solution)
should be administered within the first 24 hours
to be efficacious. If given within 30 minutes of
exposure to iodine-131, potassium iodide prevents
the uptake of iodine-131 by the thyroid gland.
Potassium iodide should be given for 7-14 days
to prevent the uptake of recycled iodine-131. The
recommended daily dose of iodide is 300mg given
as 390mg of potassium iodide. Any readily avail-
able soluble form of iodine with equivalent iodide
5.3.2 Internal Contamination
After inhalation, particles less than 5m in dia-
meter can be deposited in the alveoli. Larger parti-
cles will be limited to the mucociliary apparatus
of the tracheobronchial tree or the oropharynx. In
either area, soluble particles will be absorbed into
the blood streamvia the lymphatic system. Insoluble
particles will continue to irradiate surrounding
tissues until cleared from the respiratory tract. This
will cause inflammation and result in fibrosis and
scarring. Absorption of ingested radioactive parti-
cles depends on the solubility of the contaminant.
Iodine 131 and cesium 127 are rapidly absorbed
by the gut while plutonium, radium, and strontium
are not. The lower GI tract is the target organ for
insoluble particles that pass unchanged in the feces.
For internal contamination, decontamination is
also indicated. This will reduce the ongoing radioac-
tive injury. Recommendations can be obtained by a
RadiationSafetyOfficer orNuclearMedicinePhysi-
cian. There are several medications and chemicals
that can be used for internal decontamination.
Prussian or Berlin blue is ferric ferrocyanide.
This chemical is not absorbed by the gastro-
intestinal (GI) tract and works through two modes
of action. It decreases the absorption of many
