injuries poisoning
Radiation Exposure and Contamination
Treatment of Radiation Exposure and Contamination
Treatment of severe traumatic injuries or life-threatening medical conditions first Minimization of health care worker radiation exposure and contamination Treatment of external and internal contamination Sometimes specific measures for particular radionuclides Precautions for and treatment of compromised immune system Minimize inflammatory response Supportive care (see Evaluation and Treatment ). Trauma resuscitation of the seriously injured takes priority over decontamination efforts and must not be delayed awaiting special radiation management equipment and personnel. Standard universal precautions, as routinely used in trauma care, adequately protect the critical care team. Extensive, reliable information about principles of radiation injuries, including management, is available at theUS Department of Health and Human Services Radiation Event Medical Managementweb site. This information can be downloaded to a personal computer or smartphone in case internet connectivity is lost during a radiation incident. Consensus clinical management guidelines for the optimal management of acute radiation syndromes (ARS) were developed by an international consultancy of experts convened by the World Health Organization to consider the quality of the evidence supporting various treatment guidelines (see table). Associated trauma is more immediately life threatening than radiation exposure and must be treated expeditiously. Standard universal precautions, as routinely used in trauma care, adequately protect the critical care team. The Joint Commission mandates that all hospitals have protocols and that personnel have training to deal with patients contaminated with hazardous material, including radioactive material. Identification of radioactive contamination on patients should prompt their isolation in a designated area (if practical), decontamination, and notification of the hospital radiation safety officer, public health officials, hazardous material teams, and law enforcement agencies as appropriate to investigate the source of radioactivity. If practical, treatment area surfaces may be covered with plastic sheeting to aid in facility decontamination. This preparation should never take precedence over provision of medical stabilization procedures. Waste receptacles (labeled “Caution, Radioactive Material”), sample containers, and Geiger counters should be readily available. All equipment that has come into contact with the room or with the patient (including ambulance equipment) should remain isolated until lack of contamination has been verified. An exception is a Radiological Weapons , during which lightly contaminated critical equipment such as helicopters, ambulances, trauma rooms, and x-ray, CT, and surgical facilities should be quickly decontaminated to the extent possible and returned to service. Personnel involved in treating or transporting the patient should follow standard precautions, wearing caps, masks, gowns, gloves, and shoe covers. Used gear should be placed in specially marked bags or containers. Dosimeter badges should be worn to monitor radiation exposure. Personnel may be rotated to minimize exposure, and pregnant personnel should be excluded from the treatment area. Due to the low exposure rates anticipated from most contaminated patients, medical staff members caring for typical patients are unlikely to receive doses in excess of the occupational limit of 0.05 Sv/year. Even in the extreme case of radiation casualties from the Chernobyl nuclear reactor accident, medical personnel who treated patients in the hospital received<0.01 Sv. Several authoritative sources suggest that a dose of up to at least 0.5 Gy may be considered an acceptable risk for lifesaving activity. Typical sequence and priorities are Removing clothing and external debris Decontaminating wounds before decontaminating intact skin Cleaning the most contaminated areas first Using a radiation survey meter to monitor progress of decontamination Continuing decontamination until areas are below 2 to 3 times background radiation or there is no significant reduction between decontamination efforts Clothes are removed carefully to minimize the spread of contamination and placed in labeled containers. Clothing removal eliminates about 90% of external contamination. Foreign objects should be considered contaminated until checked with a radiation survey meter. Contaminated wounds are decontaminated before intact skin; they are irrigated with saline and gently scrubbed with a surgical sponge. Minimal debridement of wound edges may be done if there is residual contamination after multiple attempts at cleansing. Debridement beyond the wound margin is not required, although embedded radioactive shrapnel can have very high radiation exposure rates and thus should be removed using long forceps or a similar device and placed in a lead container. Contaminated skin and hair are washed with lukewarm water and mild detergent until radiation survey meter measurements indicate levels below 2 to 3 times normal background radiation or until successive washings do not significantly reduce contamination levels. All wounds are covered during washing to prevent the introduction of radioactive material. Scrubbing may be firm but should not abrade the skin. Special attention is usually required for fingernails and skinfolds. Hair that remains contaminated is removed with scissors or electric clippers; shaving is avoided. Inducing sweating (eg, placing a rubber glove over a contaminated hand) may help remove residual skin contamination. Burns are rinsed gently rather than scrubbed because scrubbing may increase injury severity. Subsequent dressing changes help remove residual contamination. Decontamination is not necessary for patients who have been irradiated by an external source and are not contaminated. Ingested radioactive material should be removed promptly by induced vomiting or lavage if exposure is recent. Frequent mouth rinsing with saline or dilutehydrogen peroxideis indicated for oral contamination. Exposed eyes should be decontaminated by directing a stream of water or saline laterally to avoid contaminating the nasolacrimal duct. The urgency and importance of using more specific treatment measures depend on the type and amount of the radionuclide, its chemical form and metabolic characteristics (eg, solubility, affinity for specific target organs), the route of contamination (eg, inhalation, ingestion, contaminated wounds), and the efficacy of the therapeutic method. The decision to treat internal contamination requires knowledge of the potential risks; consultation with a specialist (eg, Centers for Disease and Control and Prevention [CDC] or Radiation Emergency Assistance Center/Training Site [REAC/TS]) is recommended. Currentmethods to remove radioactive contaminantsfrom the body (decorporation) include Saturation of the target organ (eg,potassium iodide[KI] for iodine isotopes) (seeCDC: Potassium Iodide [KI]) Chelation at the site of entry or in body fluids followed by rapid excretion (eg, calcium or zinc diethylenetriamine penta-acetate [DTPA] for americium, californium, plutonium, and yttrium) (seeCDC: DTPA) Acceleration of the metabolic cycle of the radionuclide by isotope dilution (eg, water for hydrogen-3) Precipitation of the radionuclide in the intestinal lumen followed by fecal excretion (eg, oral calcium or aluminum phosphate solutions for strontium-90) Ion exchange in the gastrointestinal tract (eg, Prussian blue for cesium-137, rubidium-82, thallium-201) (seeCDC: Prussian Blue) include iodine allergies and certain skin disorders associated with iodine sensitivity (eg, Dermatitis Herpetiformis , urticaria vasculitis). Symptomatic treatment is given as needed and includes managing shock and hypoxia, relieving pain and anxiety, and giving sedatives (lorazepam1 to 2 mg IV as needed) to control seizures, antiemetics (metoclopramide10 to 20 mg IV every 4 to 6 hours,prochlorperazine5 to 10 mg IV every 4 to 6 hours, orondansetron4 to 8 mg IV every 8 to 12 hours) to control vomiting, and oral antidiarrheal agents (kaolin/pectin 30 to 60 mL with each loose stool orloperamide4 mg initially, then 2 mg with each loose stool) for diarrhea. There is no specific treatment for the cerebrovascular syndrome. It is universally fatal; care should address patient comfort. The gastrointestinal syndrome is treated with aggressive fluid resuscitation and electrolyte replacement. Parenteral nutrition should be initiated to promote bowel rest. In febrile patients, broad-spectrum antibiotics (eg, imipenem 500 mg IV every 6 hours) should be initiated immediately. Sepsis and Septic Shock from overwhelming infection remains the most likely cause of death. Management of the hematopoietic syndrome is similar to that of bone marrow hypoplasia and pancytopenia of any cause. Blood products should be transfused to treat anemia and thrombocytopenia, and hematopoietic growth factors (granulocyte colony-stimulating factor and granulocyte macrophage colony-stimulating factor) and broad-spectrum antibiotics should be given to treat neutropenia and neutropenic fever, respectively (see Treatment ). Patients with neutropenia should also be placed in reverse isolation. With a whole-body radiation dose Cytokinesmay be helpful. Recommended medications and dosages are Filgrastim(G-CSF) 10 micrograms per kilogram of patient weight (10 mcg/kg) daily by subcutaneous injection. Should be administered as soon as possible after suspected or confirmed exposure to radiation doses greater than 2 gray (Gy). Sargramostim(granulocyte macrophage colony-stimulating factor [GM-CSF]) 5 to 10 mcg/kg subcutaneously once a day or 200 to 400 mcg/m2subcutaneously once a day Pegfilgrastim(pegylated G - CSF) 6 mg subcutaneously once Radiation-induced sores or ulcers that fail to heal satisfactorily may be repaired by skin grafting or other surgical procedures. Aside from regular monitoring for signs of certain disorders (eg, ophthalmic examination for cataracts, thyroid function studies for thyroid disorders), there is no specific monitoring, screening, or treatment for specific organ injury or cancer. 