Decontamination should never be performed before stabilizing the patient and obtaining samples of involved areas. Efforts can be divided into two distinct processes, internal and external decontamination. Before continuing with methods of internal and external decontamination, a description of the two is in order.
Contamination occurs when an unwanted material remains on or inside the patient. External contamination is located on the surface of the body. This form of contamination is usually easily managed. Radioactive materials are not especially difficult to remove. In most cases, soap and water will remove the external contamination that may be located in the skin or hair.
Internal contamination is located internal to the skin and is more difficult to treat because it may have already entered a metabolic pathway. Full knowledge of the chemistry, physiological properties, and modes of excretion is required. This knowledge is available in several texts. Most notably, NCRP #65 (Management of Persons Accidentally Contaminated with Radionuclides) lists many of the biologic pathways for the elements.
Radioactive external contamination is often easily treated by using soap and water. The popular movies showing abrasive cleaning of the skin with corn meal and bleach is detrimental. This action may actually cause an easily managed external contamination to become internal contamination.
The method for any solution used is the same. Wash, dry, then resurvey. The area should be washed with a clean gauze sponge. The gauze should be wet with the cleaning solution, the affected area gently scrubbed, and then the gauze disposed of. The commonly used technique of wetting the gauze, cleaning the area, rewetting the gauze, and cleaning again should be avoided. The potential for contamination of the basin of cleaning solution occurs when moving back and forth between a contaminated area and the basin. A gauze should be used once, then discarded.
The affected area should next be dried thoroughly. Contaminated cleaning solution may remain on the patient. Drying with an absorbent disposable material or gauze will remove any contaminants that were washed off by scrubbing. Finally, when the drying is complete, the area should be resurveyed to check the efficacy of the decontamination efforts. If contamination persists but the amount has decreased, continue using the same solution. If three successive washings do not result in a significant decrease, progression to a different cleaning solution is indicated.
The mildest cleaning solution should be the one to start with for intact skin. For treatment of wounds that are contaminated, the cleansing solution normally used for cleaning should beemployed. Betadine is quite effective in its cleaning action and offers the additional protection of blocking the thyroid from any radioactive iodine uptake.
Should the first solution not be effective in cleansing, other solutions can be tried. Betadine, hydrogen peroxide, Phisohex, or Dakins solution are also effective cleansers. Persistent contamination on intact skin can sometimes be removed by the use of hand lotion.
Internal contamination poses a special problem. The offending agent has passed the protective layer of the skin and is now somewhere inside the patient. The location of the contaminant depends on the chemical composition and its biological distribution. A thorough knowledge of the mechanisms of enhancing excretion of these materials is useful in the therapy of internal contamination.
Iodine is almost completely absorbed by the thyroid gland. The iodine not absorbed by the thyroid is excreted primarily via the urine. Since iodine becomes organified within the thyroid, it is imperative to begin treatment early. This is performed by providing the patient with a comparatively large dose of stable iodine. Ten drops of super saturated potassium iodide sloution SSKI in a glass of water or juice followed by three drops per day for three days should suffice to block the thyroid.
Treatment with SSKI within the first hour of contamination results in about 90% effectiveness in preventing thyroid uptake. At four hours, it is only about 50% effective. At 24 hours, SSKI offers no benefit in preventing thyroid uptake of iodine.
Betadine, as mentioned earlier, offers a certain amount of protection. Iodine is absorbed through intact skin and wounds. Betadine contains enough iodine as to help prevent thyroid uptake of iodine. If iodine contamination is suspected however, treatment with SSKI is suggested.
Like iodine, tritium is also absorbed through intact skin. Tritium behaves like water and distributes throughout the fluid spaces of the body. Treatment consists of aggressive fluid replacement and diuresis. Caution should be taken to regularly monitor the electrolytes during this treatment.
Strontium behaves like calcium within the body. It is taken up by the bones and incorporated into the bony matrix. To prevent this, calcium can be given to help displace the strontium and enhance the excretion through the kidneys.
Many other materials cannot easily be excreted. In these cases, materials such as desferoxamine, EDTA, BAL and other chelating agents can be used to bind the material and promote excretion. Great care must be taken when using these chelating agents as they donot discriminate in what they bind between radioactive and non-radioactive elements. Massive and dangerous electrolyte disturbances may result from the use of these agents.
It is possible that a significant amount of material may be inhaled and deposit within the lungs. There is some question if bronchial lavage is indicated in these cases. Alpha emitters that deposit their radiation doses locally may result in pulmonary fibrosis. Bronchial lavage has been proposed as a means by which these contaminants may be removed.
Bronchial lavage however is not without complications itself. It may not result in complete removal of the contaminant and may cause significant irritation of the bronchial lining. Its use should be limited to situations where there are large amounts of inhaled contamination.
Large doses of radiation exposure that result in the depression of white cells and platelets may require a bone marrow transplant. This too is a procedure that is not to be taken lightly. The complications of bone marrow transplant may be life threatening. Depending on the areas exposed, an autologous transplant may not be possible. Its use should be confined to very high doses of radiation exposure. Transplanatation in the acute radiation syndrome situation is highly controversial.