Treatment of radiation damage

Ionizing exposure may be accompanied by physical injury (e.g. from an explosion or fall); the accompanying injury may be more life-threatening than the radiation exposure and requires immediate treatment. Treatment of serious injury should not be delayed until radiation diagnostic and protection services arrive. Standard precautions routinely used in trauma care are sufficient to protect rescuers.

Hospitalization

The certification service requires that all hospitals have protocols and that staff be trained to deal with radioactive contamination. When radioactive contamination is detected, a patient is isolated in a special room, decontaminated, and the hospital's radiation safety officer, health authorities, hazardous materials service, and law enforcement are notified to actively search for the source of the radioactivity.

Contaminated body surfaces can be covered with a protective plastic screen to facilitate subsequent decontamination. This should never delay medical care. Waste containers (labeled "Caution, Radiation"), sample containers, and Geiger counters should be readily available. All equipment that has been in contact with the room or the patient (including ambulance equipment) should be isolated until the degree of contamination has been assessed.

Personnel must wear caps, masks, gowns, gloves, and shoe covers, and all exposed areas of protective clothing must be sealed with adhesive tape. Used material is placed in labeled bags or containers. Personnel must wear individual dosimeters to monitor radiation contamination. Personnel should be rotated to minimize exposure. Pregnant women are not allowed to treat patients.

Decontamination

After isolation in a special room, the victim is carefully removed from clothing, which must be placed in appropriate pre-prepared containers to minimize the spread of contamination. About 90% of external contamination is removed with clothing. Contaminated skin is washed with a warm, weak soap solution until the radioactivity level decreases to two times the background value or until successive washes significantly reduce the contamination level. During washing, all wounds on the body must be covered to prevent radioactive substances from getting into them. Skin cleaning devices must be firm, but at the same time not scrape the skin. Particular attention is usually paid to nails and skin folds. Special chelating solutions containing ethylenediaminetetraacetic acid are not needed for decontamination.

The wounds are checked with a Geiger counter and washed until the radiation level is normal. Surgical debridement may be required to remove particles stuck in the wound. Foreign bodies removed from the wound are placed in special lead containers.

Ingested radioactive materials are removed as quickly as possible by inducing vomiting or by gastric lavage if the exposure was recent.

If the oral cavity is contaminated, rinse frequently with saline or diluted hydrogen peroxide. Contamination of the eyes is deactivated with a directed stream of water or saline in such a way as to avoid contamination of the nasolacrimal canal.

Other, more specific measures to reduce internal contamination depend on the particular radionuclide and the results of the mandatory specialist consultation. If exposure to radioactive iodine has occurred (after a nuclear reactor accident or a nuclear explosion), the patient should be given potassium iodide (KI) as soon as possible; its effectiveness is significantly reduced within a few hours of exposure. KI can be given either in tablet form or as a saturated solution (dosage: adults 130 mg; ages 3-18 years 65 mg; ages 1-36 months 32 mg; ages under one month 16 mg). Various chelating agents are used to treat internal contamination with other radioactive substances: saturated K (radioactive iodine), calcium or zinc diethylenetriamine pentaacetate (plutonium-239 or yttrium-90), Prussian blue (cesium-137, rubidium-82, thallium-201), or oral calcium preparations or aluminum phosphate solution (radioactive strontium).

Decontamination is not indicated for patients who have been exposed to external radiation sources without contamination.

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Specific treatment of radiation injuries

If necessary, symptomatic treatment is prescribed, including treatment of shock and anoxia, analgesics and anxiolytics, sedatives (lorazepam 1-2 mg intravenously) for the prevention of seizures, antiemetics (metoclopramide 10-20 mg intravenously every 4-6 hours; prochlorperazine 5-10 mg intravenously every 4-6 hours; ondansetron 4-8 mg intravenously every 8-12 hours), and antidiarrheals (kaolin + pectin 30-60 ml orally for each case of loose stools; loperamide at an initial dose of 4 mg orally, then 2 mg orally for each case of loose stools).

There is no specific treatment for cerebral syndrome, the condition inevitably ends in death. Help consists of creating maximum comfort for the patient.

Gastrointestinal syndrome is treated with aggressive fluid and electrolyte replacement. Parenteral nutrition allows for intestinal unloading. If the patient is febrile, broad-spectrum antibiotics (eg, imipenem + [cilastine] 500 mg intravenously every 6 hours) should be started immediately. Despite this, shock from incurable infection remains the most likely cause of death.

The treatment of the hematologic syndrome is the same as that for bone marrow hypoplasia and pancytopenia of any etiology. Anemia and thrombocytopenia are treated with blood components transfusions, hematopoietic growth factors (granulocyte colony-stimulating factor and granulocyte macrophage colony-stimulating factor) and broad-spectrum antibiotics for neutropenia and neutropenic fever, respectively. Neutropenic patients should be isolated. The likelihood of bone marrow recovery is extremely low after irradiation with doses >4 Gy, so hematopoietic growth factors should be started as soon as possible. Stem cell transplants have had limited success but should be considered after irradiation with doses >7–8 Gy (see the relevant section).

Other than regular monitoring of symptoms of the disease (e.g. eye examination for cataracts, thyroid function testing), there are no specific monitoring or treatments for specific organ damage. Post-radiation cancer is treated in the same way as spontaneous cancer of the same location.

Prevention of radiation damage

Protection from radiation exposure consists of minimizing exposure time, maximizing distance from the source, and using protective shields. Shielding from a known specific radioactive substance can be quite effective (e.g., with lead aprons or commercial transparent shields), but protection from contamination by radionuclides from most major disasters (e.g., a nuclear accident or explosion) is not possible. Therefore, after a radiation release, if possible, people in the contaminated area should be evacuated for 1 week if the expected dose is >0.05 Gy, and permanently if the predicted lifetime dose is >1 Gy. When evacuation is not possible, sheltering in a concrete or metal structure (e.g., a basement) may provide some protection.

People living within 16 km (10 mi) of a nuclear power plant should have potassium iodide tablets available. They should be available from pharmacies and health care facilities. Many drugs and chemicals (such as sulfhydryl compounds) increase survival in animals when given before exposure. However, none are as effective in humans.

All personnel handling radioactive materials should wear dosimeters and be regularly monitored for symptoms of excessive radiation exposure. The standard occupational threshold is 0.05 Gy/year. For emergency medical personnel, the recommended dose thresholds are 0.05 Gy for any non-life-threatening event and 0.25 Gy for any life-threatening event.