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Emergency Department Management of Radiation Casualties. CAUTION. This presentation, "Emergency Department Management of Radiation Casualties,” was prepared as a public service by the Health Physics Society for hospital staff training.
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Emergency Department Management of Radiation Casualties CAUTION
This presentation, "Emergency Department Management of Radiation Casualties,” was prepared as a public service by the Health Physics Society for hospital staff training. The presentation includes talking points on the Notes pages, which can be viewed if you go to the File Menu and "Save As" a PowerPoint file to your computer. The talking points are provided with each slide to assist the presenter in answering questions. It is not expected that all the information in the talking points will be presented during the training. The presentation can be edited to fit the needs of the user. The authors request that that appropriate attribution be given for this material and would like to know who is presenting it and to what groups. That information and comments may be sent to Jerrold T. Bushberg, PhD, UC Davis Health System, at jtbushberg@ucdavis.edu. Version 2.9
Scope of Training • Characteristics of ionizing radiation and radioactive materials • Differentiation between radiation exposure and radioactive material contamination • Staff radiation protection procedures and practices • Facility preparation
Scope of Training (Cont.) • Patient assessment and management of radioactive material contamination and radiation injuries • Health effects of acute and chronic radiation exposure • Psychosocial considerations • Facility recovery • Resources
Ionizing Radiation • Ionizing radiation is radiation capable of imparting its energy to the body and causing chemical changes. • Ionizing radiation is emitted by: • - Radioactive material. • Some devices such as x-ray machines.
Types of Ionizing Radiation Alpha Particles Stopped by a sheet of paper Radiation Source Beta Particles Stopped by a layer of clothing or less than an inch of a substance (e.g. plastic) Gamma Rays Stopped by inches to feet of concrete or less than an inch of lead
Radiation Units Measure of Amount of radioactive material Ionization in air Absorbed energy per mass Absorbed dose weighted by type of radiation Quantity Activity Exposure Absorbed Dose Dose Equivalent Unit curie (Ci) roentgen (R) rad rem For most types of radiation 1 R 1 rad 1 rem
Radiation Doses and Dose Limits Flight from Los Angeles to London 5 mrem Annual public dose limit 100 mrem Annual natural background 300 mrem Fetal dose limit 500 mrem Barium enema 870 mrem Annual radiation worker dose limit 5,000 mrem Heart catheterization (skin dose) 26,000 mrem Life-saving actions guidance (NCRP-116) 50,000 mrem Mild acute radiation syndrome 200,000 mrem LD50/60 for humans (bone marrow dose) 350,000 mrem Radiation therapy (localized & fractionated) 6,000,000 mrem
Radioactive Material • Radioactive material consists of atoms with unstable nuclei. • The atoms spontaneously change (decay) to more stable forms and emit radiation. • A person who is contaminated has radioactive material on his/her skin or inside his/her body (e.g., inhalation, ingestion, or wound contamination).
Half-Life (HL) • Physical Half-Life Time (in minutes, hours, days, or years) required for the activity of a radioactive material to decrease by one half due to radioactive decay • Biological Half-Life Time required for the body to eliminate half of the radioactive material (depends on the chemical form) • Effective Half-Life The net effect of the combination of the physical and biological half-lives in removing the radioactive material from the body • Half-lives range from fractions of seconds to millions of years • 1 HL = 50% 2 HL = 25% 3 HL = 12.5%
Examples of Radioactive Materials Physical RadionuclideHalf-LifeActivityUse Cesium-137* 30 yrs 1.5 x 106 Ci Blood Irradiator Cobalt-60 5 yrs 15,000 Ci Cancer Therapy Plutonium-23924,000 yrs 600 Ci Nuclear Weapon Iridium-192 74 days 100 Ci Industrial Radiography Hydrogen-3 12 yrs 12 Ci Exit Signs Strontium-90 29 yrs 0.1 Ci Eye Therapy Device Iodine-131 8 days 0.015 Ci Nuclear Medicine Therapy Technetium-99m 6 hrs 0.025 Ci Diagnostic Imaging Americium-241 432 yrs 0.000005 Ci Smoke Detectors Radon-222 4 days 1 pCi/l Environmental Level *Potential use in radiological dispersion device
Types of Radiation Hazards Internal Contamination • External Exposure - • Whole-body or partial-body (no radiation hazard to EMS staff) • Contaminated- • External radioactive material: on the skin • Internal radioactive material: inhaled, swallowed, absorbed through skin or wounds External Contamination External Exposure
Causes of Radiation Exposure/Contamination • Accidents • Nuclear reactor • Medical radiation therapy • Industrial irradiator • Lost/stolen medical or industrial radioactive sources • Transportation • Terrorist Event • Radiological dispersal device (dirty bomb) • Attack on or sabotage of a nuclear facility • Low-yield nuclear weapon
Scope of Event Event Number of Deaths Most Deaths Due to Radiation None/Few Radiation Accident Few/Moderate Radioactive Blast Trauma (Depends on Dispersal size of explosion and Device proximity of persons) Blast Trauma Low-Yield Large Thermal Burns (e.g., tens of thousands in an urban area even from 0.1 kT weapon) NuclearWeapon Radiation Exposure Fallout (Depends on Distance)
Radiation ProtectionReducing Radiation Exposure • Time • Minimize time spent near radiation sources. To Limit Caregiver Dose to 5 rem Distance Rate Stay time 1 ft 12.5 R/hr 24 min 2 ft 3.1 R/hr 1.6 hr 5 ft 0.5 R/hr 10 hr 8 ft 0.2 R/hr 25 hr • Distance • Maintain maximal practical distance from radiation source. • Shielding • Place radioactive sources in a lead container.
Protecting Staff from Contamination • Follow universal precautions. • Survey hands and clothing with radiation meter. • Replace contaminated gloves or clothing. • Keep the work area free of contamination. • Key Points • Contamination is easy to detect and most of it can be removed. • It is very unlikely that ED staff will receive large radiation doses from treating contaminated patients.
Mass Casualties, Contaminated butUninjured People, and Worried Well • An incident caused by nuclear terrorism may create large numbers of contaminated people who are not injured and worried people who may not be injured or contaminated. • Measures must be taken to prevent these people from overwhelming the emergency department. • A triage site should be established outside the ED to intercept such people and divert them to appropriate locations. • Triage site should be staffed with medical staff and security personnel. • Precautions should be taken so that people cannot avoid the triage center and reach the ED.
Decontamination Center • Establish a decontamination center for people who are contaminated, but not significantly injured. • Center should provide showers for many people. • Replacement clothing must be available. • Provisions to transport or shelter people after decontamination may be necessary. • Staff decontamination center with medical staff with a radiological background, health physicists or other staff trained in decontamination and use of radiation survey meters, and psychological counselors.
Psychological Casualties • Terrorist acts involving toxic agents (especially radiation) are perceived as very threatening. • Mass-casualty incidents caused by nuclear terrorism will create large numbers of worried people who may not be injured or contaminated. • Establish a center to provide psychological support to such people. • Set up a center in the hospital to provide psychological support for staff.
Facility Preparation • Activate hospital plan: • Obtain radiation survey meters. • Call for additional support: Staff from Nuclear Medicine, Radiation Oncology, Radiation Safety (Health Physics). • Establish area for decontamination of uninjured persons. • Establish triage area. • Plan to control contamination: • Instruct staff to use universal precautions and double glove. • Establish multiple receptacles for contaminated waste. • Protect floor with covering if time allows. • For transport of contaminated patients into ED, designate separate entrance, designate one side of corridor, or transfer to clean gurney before entering, if time allows.
ED Staff Radiation Survey & Charting Contaminated Waste Radiation Survey STEP OFF PAD Waste Treatment Area Layout Separate Entrance CONTAMINATED AREA Trauma Room HOT LINE BUFFER ZONE Clean Gloves, Masks, Gowns, Booties CLEAN AREA
Detecting and Measuring Radiation • Instruments • Locate contamination - GM Survey Meter (Geiger counter) • Measure exposure rate - Ion Chamber • Personal Dosimeters - Measure doses to staff • Radiation Badge - Film/TLD • Self-reading dosimeter (analog and digital)
Patient Management - Priorities Triage • Medical triage is the highest priority. • Radiation exposure and contamination are secondary considerations. • Degree of decontamination is dictated by number of and capacity to treat other injured patients.
Patient Management - Triage Triage based on: • Injuries • Signs and symptoms - nausea, vomiting, fatigue, diarrhea • History - Where were you when the bomb exploded? • Contamination survey
Patient Management - Decontamination • Carefully remove and bag patient’s clothing and personal belongings (typically removes 95 percent of contamination). • Survey patient and, if practical, collect samples. • Handle foreign objects with care until proven nonradioactive with survey meter. • Decontamination priorities: • Decontaminate wounds first, then intact skin. • Start with highest levels of contamination. • Change outer gloves frequently to minimize spread of contamination.
Patient Management - Decontamination (Cont.) • Protect noncontaminated wounds with waterproof dressings. • Contaminated wounds: • Irrigate and gently scrub with surgical sponge. • Extend wound debridement for removal of contamination only in extreme cases and upon expert advice. • Avoid overly aggressive decontamination. • Change dressings frequently. • Decontaminate intact skin and hair by washing with soap & water. • Remove stubborn contamination on hair by cutting with scissors or electric clippers. • Promote sweating. • Use survey meter to monitor progress of decontamination.
Patient Management - Decontamination (Cont.) • Cease decontamination of skin and wounds: • When the area is less than twice background, or • When there is no significant reduction between decon efforts, and • Before intact skin becomes abraded. • Contaminated thermal burns • Gently rinse. Washing may increase severity of injury. • Additional contamination will be removed when dressings are changed. • Do not delay surgery or other necessary medical procedures or exams . . . residual contamination can be controlled.
Treatment of Internal Contamination • Radionuclide-specific • Most effective when administered early • May need to act on preliminary information • NCRP Report No. 65, Management of Persons Accidentally Contaminated with Radionuclides RadionuclideTreatment Route Cesium-137 Prussian blue Oral Iodine-125/131 Potassium iodide Oral Strontium-90 Aluminum phosphate Oral Americium-241/ Ca- and Zn-DTPA IV infusion, Plutonium-239/ nebulizer Cobalt-60
Patient Management - Patient Transfer Transport injured, contaminated patient into or from the ED: • Cover clean gurney with two sheets. • Lift patient onto clean gurney. • Wrap sheets over patient. • Roll gurney into ED or out of treatment room.
Facility Recovery • Remove waste from the emergency department and triage area. • Survey facility for contamination. • Decontaminate as necessary: • Normal cleaning routines (mop, strip waxed floors) typically very effective. • Periodically reassess contamination levels. • Replace furniture, floor tiles, etc., that cannot be adequately decontaminated. • Decontamination Goal: Less than twice normal background . . . higher levels may be acceptable.
Radiation Sickness Acute Radiation Syndrome • Occurs only in patients who have received very high radiation doses (greater than approximately 100 rem) to most of the body • Dose ~15 rem • no symptoms, possible chromosomal aberrations • Dose ~50 rem • no symptoms, minor decreases in white cells and platelets
Acute Radiation Syndrome (Cont.)For Doses > 100 rem • Prodromal Stage • Symptoms may include nausea, vomiting, diarrhea, and fatigue. • Higher doses produce more rapid onset and greater severity. • Latent Period (Interval) • Patient appears to recover. • Decreases with increasing dose. • Manifest Illness Stage • Hematopoietic • Gastrointestinal • CNS Time of Onset Severity of Effect
Acute Radiation Syndrome (Cont.)Hematopoietic Component - latent period from weeks to days • Dose ~100 rem • ~10 percent exhibit nausea and vomiting within 48 hrs • mildly depressed blood counts • Dose ~350 rem • ~90 percent exhibit nausea/vomiting within 12 hrs, 10 percent exhibit diarrhea within 8 hrs • severe bone marrow depression • ~50 percent mortality without supportive care • Dose ~500 rem • ~50 percent mortality with supportive care • Dose ~1,000 rem • 90-100 percent mortality despite supportive care
Acute Radiation Syndrome (Cont.)Gastrointestinal and CNS Components • Dose > 1,000 rem - damage to GI system • severe nausea, vomiting, and diarrhea (within minutes) • short latent period (days to hours) • usually fatal in weeks to days • Dose > 3,000 rem - damage to CNS • vomiting, diarrhea, confusion, and severe hypotension within minutes • collapse of cardiovascular system and CNS • fatal within 24 to 72 hours
Treatment of Large External Exposures • Estimating the severity of radiation injury is difficult. • Signs and symptoms (N,V,D,F): Rapid onset and greater severity indicate higher doses. Can be psychosomatic. • CBC with absolute lymphocyte count • Chromosomal analysis of lymphocytes (requires special lab) • Treat symptomatically. Prevention and management of infection is the primary objective. • Hematopoietic growth factors, e.g., GM-CSF, G-CSF (24-48 hours) • Irradiated blood products • Antibiotics/reverse isolation • Electrolytes • Seek the guidance of experts. • Radiation Emergency Assistance Center/Training Site (REAC/TS) • Medical Radiobiology Advisory Team (MRAT)
Localized Radiation Effects - Organ System Threshold Effects • Skin - No visible injuries < 100 rem • Main erythema, epilation >500 rem • Moist desquamation >1,800 rem • Ulceration/Necrosis >2,400 rem • Cataracts • Acute exposure >200 rem • Chronic exposure >600 rem • Permanent Sterility • Female >250 rem • Male >350 rem
Emergency Surgery Hematopoietic Recovery No Surgery Surgery Permitted 24-48 Hours After adequate hematopoietic recovery ~3 Months Special Considerations • High radiation dose and trauma interact synergistically to increase mortality. • Close wounds on patients with doses > 100 rem. • Wound care, burn care, and surgery should be done in the first 48 hours or delayed for 2 to 3 months (> 100 rem).
Chronic Health Effects from Radiation • Radiation is a weak carcinogen at low doses. • There are no unique effects (type, latency, pathology). • Natural incidence of cancer is ~40 percent; mortality ~25 percent. • Risk of fatal cancer is estimated as ~5 percent per 100 rem. • A dose of 5 rem increases the risk of fatal cancer by ~0.25 percent. • A dose of 25 rem increases the risk of fatal cancer by ~1.25 percent.
What Are the Risks to Future Children?Hereditary Effects • Magnitude of hereditary risk per rem is ~10percent that of fatal cancer risk. • Risk to caregivers who would likely receive low doses is very small; 5 rem increases the risk of severe hereditary effects by ~0.02percent. • Risk of severe hereditary effects to a patient population receiving high doses is estimated as ~0.4percent per 100 rem.
Fetal IrradiationNo significant risk of adverse developmental effects below 10 rem Weeks After Fertilization Period of Development Effects <2 2-7 7-40 All Pre-implantation Organogenesis Fetal • Little chance of malformation • Most probable effect, if any, is death of embryo • Reduced lethal effects • Teratogenic effects • Growth retardation • Impaired mental ability • Growth retardation with higher doses • Increased childhood cancer risk (~0.6 percent per 10 rem)
Key Points • Medical stabilization is the highest priority. • Train/drill to ensure competence and confidence. • Preplan to ensure adequate supplies and survey instruments are available. • Universal precautions and decontaminating patients minimize exposure and contamination risk. • Early symptoms and their intensity are an indication of the severity of the radiation injury. • The first 24 hours are the worst; then you will likely have many additional resources.
Resources • Radiation Emergency Assistance Center/Training Site (REAC/TS), 865-576-1005, www.orise.orau.gov/reacts • Medical Radiobiology Advisory Team (MRAT) Armed Forces Radiobiology Research Institute (AFRRI), 301-295-0530, www.afrri.usuhs.mil • Medical Management of Radiological Casualties Handbook, 2003; and Terrorism with Ionizing Radiation Pocket Guide • Web sites: • http://remm.nlm.gov/ - Radiation Event Medical Management by Department of Health & Human Services • http://emergency.cdc.gov/radiation/ - Response to Radiation Emergencies by the Centers for Disease Control and Prevention • www.acr.org - “Disaster Preparedness for Radiology Professionals” by the American College of Radiology, (search for “disaster” on website) • www1.va.gov/emshg - Medical Treatment of Radiological Casualties
Resources • Books: • Gusev I, Guskova A, Mettler F, eds. Medical management of radiation accidents, 2nd ed. Boca Raton, FL: CRC Press; 2001. • Mettler F, Upton A. Medical effects of ionizing radiation, 2nd ed. Philadelphia: Saunders; 1995. • The Medical Basis for Radiation-Accident Preparedness; REAC/TS Conference, 2002. • National Council on Radiation Protection and Measurements. Management of persons accidentally contaminated with radionuclides. Bethesda, MD: NCRP; NCRP Report No. 65. • National Council on Radiation Protection and Measurements. Management of terrorist events involving radioactive material. Bethesda, MD: NCRP; NCRP Report No. 138. • Articles: • Mettler F, Voelz G. Major radiation exposure - What to expect and how to respond. New England Journal of Medicine 346:1554-1561; 2002. • Waselenko J, et.al. Medical management of the acute radiation syndrome: Recommendations of the strategic national stockpile radiation working group. Annals of Internal Medicine 140:1037-1051; 2004. • Gerber GB, Thomas RG, eds. Guidebook for the treatment of accidental internal radionuclide contamination of workers. Radiation Protection Dosimetry. 41:1; 1992.
Acknowledgments Prepared by the Medical Response Subcommittee of the National Health Physics Society Homeland Security Committee. Jerrold T. Bushberg, PhD, ChairKenneth L. Miller, MS Marcia Hartman, MS Robert Derlet, MDVictoria Ritter, RN, MBA Edwin M. Leidholdt, Jr., PhD ConsultantsFred A. Mettler, Jr., MD Niel Wald, MD William E. Dickerson, MD Appreciation to Linda Kroger, MS, who assisted in this effort.
Health Physics Society* Version 2.9 Disclaimer: The information contained herein was current as of May 9, 2009, and is intended for educational purposes only. The authors and the Health Physics Society (HPS) do not assume any responsibility for the accuracy of the information presented herein. The authors and the HPS are not liable for any legal claims or damages that arise from acts or omissions that occur based on its use. *The Health Physics Society is a non profit scientific professional organization whose mission is to promote the practice of radiation safety. Since its formation in 1956, the Society has grown to approximately 6,000 scientists, physicians, engineers, lawyers, and other professionals representing academia, industry, government, national laboratories, the department of defense, and other organizations. Society activities include encouraging research in radiation science, developing standards, and disseminating radiation safety information. Society members are involved in understanding, evaluating, and controlling the potential risks from radiation relative to the benefits. Official position statements are prepared and adopted in accordance with standard policies and procedures of the Society. The Society may be contacted at: 1313 Dolley Madison Blvd., Suite 402, McLean, VA 22101; phone: 703-790-1745; FAX: 703-790-2672; email: HPS@BurkInc.com.