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The Burn Center and Radiation Incidents. David J. Barillo, MD, FACS COL MC USAR Commander, FEMA Burn Specialty Team 2. Disclaimers. I have no financial interests in any of this
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The Burn Center and Radiation Incidents David J. Barillo, MD, FACS COL MC USAR Commander, FEMA Burn Specialty Team 2
Disclaimers • I have no financial interests in any of this • Views expressed are my own and do not reflect official policy of my various employers, including FEMA, the Dept of Defense or the US Army • Don’t take notes: presentation and references are online at www.burndisaster.com
OVERVIEW • Types of radiation • Units of radiation measurement • Sources of radiation / radiation patients • Treatment considerations • References
Alpha particle • Rare and emitted by limited number of • substances including plutonium • A large heavy particle carrying significant energy due to mass • Easily blocked: most stopped by paper • Not particularly dangerous externally • An internal contamination threat • Needs special instruments to detect: not picked up by Geiger Counter • Most substances that emit alpha particles also emit beta and gamma
Beta particle • High energy electrons • Example: tritium • Blocked by thin lead shielding • Damage depends on length of exposure and energy of electrons • Tends to cause burns • Beta and Gamma are the clinically relevant exposures ARS with cutaneous syndrome from beta and Gamma radiation at Chernobyl (Ricks p 355)
Neutrons • Rarest particle • Needs specialized instruments to detect • Not usually found outside of the center of nuclear reactors or the middle of nuclear weapon blasts • Neutron bombardment can make non radioactive substances into radioactive substances (inside of reactors/blasts) • Best shielding is water
Gamma Radiation • High-frequency electromagnetic radiation • Easily detected • Hard to shield against (thick lead) • Distance works best
Measurement • Dosimeters • Detection Devices • Biologic assays • Rapid estimation by timing of symptoms
Radiation Dose • R: Roentgen • An early unit for measuring gamma or X-radiation . • The amount of gamma or X radiation needed to ionize air (0.000258 coulomb of energy per kg of air) • Doesn’t work well for high energy XR or nuclear particles • 1 R is roughly = 1 RAD = 1 REM • 1 R = 0.88 RAD in air
Radiation Dose • RAD • Radiation Absorbed Dose • One RAD = 100 ergs deposited in 1 gram of any material (living or not)
Radiation Dose • REM • Roentgen Equivalent Man • The quantity of any ionizing radiation which has the same biological effectiveness as 1 rad of X-rays • 1 REM is roughly = 1 RAD = 1 R
Radiation Dose • Gy (Grey) • The International System of Units (SI) measure of radiation • 1 Gy = 100 Rads • 10 milligray (mGy) = 1 Rad= 1 R = 1 REM
Radiation Dose • Sv (Sievert) • The Si unit of ionizing radiation • Defined as the dose of ionizing radiation that has the same biological effectiveness as 1 Gy of X-rays • 1 Sv = 100 REM = roughly 100 RADS, 100 R or 1 Gy • 10 millisieverts (mSv) = 1 REM= 1 RAD= 1 R • Sv is now the preferred unit
Radiation Dosehow much is OK? • Public: 0.1 - 0.5 REM/yr (100-500 mREM) • Occupational: 5 REM/yr • Emergency lifesaving: 50 -100 REM whole body • Emergency nonlifesaving: 25 REM REF: Mettler and National Council on Radiation Protection
Radiation Dosehow much is bad? • 50 -200 R: headache, 5% hospitalization/death • 200-500 R: N/V, 90% hospitalization 50% death rate • 800 R whole body: no long-term survival recorded • 1000-5000 R: 100% mortality in 30 days
Radiation Sources COMMON • Natural • Man-made (cigarettes, smoke detectors, watch dials) • Medical ( both diagnostic and therapeutic) • Industrial, including nuclear power • Dirty Bombs • Nuclear weapons UNCOMMON
CXR: 40 mRAD CT: 1000 - 5000 mRAD Panorex: 1000mRAD Ref: Mettler
Radiation RegistryRadiation Emergency Assistance / Training Site, Oak Ridge • Whole body dose > 25 REM • Skin dose > 600 REM • Absorbed organ dose from external source > 75 REM • Internal contamination => one half permissible body burden • Medical misadventures at doses above
Radiation RegistryRadiation Emergency Assistance / Training Site • Approximately 20 significant events / year (10-15 in USA) • 50-60 assistance calls per year, 2/3 do not involve significant exposure • Worldwide 1944-1987: 290 accidents, 136,607 people, 24,845 significant exposures, 65 deaths (half from Chernobyl). 1990-2002
ISOTOPE R/min 137 Cs 513 192 Ir 813 236 Ra 1310 60 Co 2075 Ref: Mettler
Yanango HydroelectricPlant, Lima Peru 1999 • Industrial radiography 192 Ir source • lost and carried home in pants pocket • of a welder • Estimated exposure 1-3 Gy over 6 hr • Nausea and erythema at 6 hrs • Photo is remaining injury at 2 months • Transfer to French burn center day 91 • R hip disarticulation, colostomy, • uretheral fistulae, pelvis radionecrosis Ref: Ricks pp 361
Dirty Bomb • A terrorist or area-denial device involving addition of any radioactive substance to conventional explosives • Most of the damage would be from the conventional explosives • Radioactive contamination of the wounds would significantly complicate triage, transport and management • Widespread fear and panic • Has never actually been carried out (PBS) • British Intelligence thinks that Al Qaeda may have built at least one small device from medical sources. IAEA secured several unguarded medical cobalt sources in Afghanistan in 2002 (PBS)
Nuclear Weapons Hiroshima, Japan August 6, 1945 • 2000 ft airburst of a 60 kg • U235 fission bomb (13 KT) • Estimated 80,000 • immediate fatalities in a • total population of 255,000 • Damage or loss of 90 % • of buildings • burns were present in: 50% of fatalities • 65% of survivors
Nuclear Weapons • Won’t be seen outside of a major war involving big countries • Won’t ‘go nuclear’ unless intentionally detonated in a very specific manner • Estimated 50 incidents of nuclear weapon loss, accident, crash or fire since the 1940’s with ZERO nuclear detonations. • The (conventional) high-explosive component can explode, making large messes Palomares, Spain, 1966: 650 contaminated acres of soil packaged into 4,810 55 gal drums & shipped thru the PORT OF CHARLESTON, SC for burial at the Savannah River Site, Aiken SC Ref: Mettler et al 1990
Treatment • Acute vs chronic • Whole body vs local • Exposure vs contamination • Internal vs external contamination • Isolated radiation vs radiation plus trauma
Outcomes of combined radiation and trauma injury are worse than either alone
Treatment guidelines • Decontaminate ON-SCENE whenever possible • Any fixed facility utilizing radioactive substances has both technical expertise and decontamination facilities: seek out both • If you must transport the contaminated, do not use rotary wing aircraft
Treatment guidelines • Someone exposedto radiation is not radioactive. In virtually NO case does a nuclear weapon casualty become radioactive • Someone contaminated with fallout or other radioactive material is not radioactive, but the stuff on the casualty IS radioactive and needs to be removed (think of it as radioactive dirt). • Remove the clothing, wash or shower the patient, and then treat like anyone else • Bloodborne PPE, disposable items
Treatment guidelines • Internal contamination may result from inhalation or ingestion of a radioactive substance, or passage of radioactive materials thru open wounds • Internally contaminated victims with intact skin pose little hazard, but isolate any body fluids or waste • Internal contamination resulting from explosions with remaining radioactive substances embedded in open wounds CAN pose a risk to rescuers or medical teams
Personal Protection • Time • Distance • Shielding Absorbed dose varies as the inverse square of the distance between source and patient double distance = ¼ of the radiation triple distance = 1/9th of the radiation Ref: Mettler
Seek Advice • Radiology, Nuclear Medicine and Health Physics • Fire Department/Hazmat Team • REAC/TS (www.orau.gov/reacts/) • Dept of Energy Oak Ridge Op Center 1 865 576 1005 (ask for REAC/TS)
Triage • Most immediate or early deaths from radiation incidents are due to concurrent trauma and not to radiation • Basic guide: deal with the life-threatening injuries first, worry about the radiation injury later
Exposure estimation based on symptoms • Early severe CNS failure and convulsions: 5000 Rad (50 Gy) -all will die in 2 days • Cardiovascular instability or collapse: similar. Hypotension in a radiation MASCAL setting is expectant • Vomiting within 4 hours: 300 Rad (3 Gy) Without medical care, 50% will die within 2 months • Vomiting in 50% of victims within 6 hours: 100-200 Rad (1-2 Gy) • No noticeable effects: under 100 Rad (1 Gy)
nuclear war triage • First triage and treat conventional injuries • Next determine exposure lymphocytes > 1500: no rx necessary lymphocytes 500-1000:severe radiation injury lymphocytes < 500: may prove fatal not detectable: survival very unlikely • Finally treat according to exposure or resources
ARS Hematopoietic • Seen with exposure of 70 R or higher • 30 R may cause mild symptoms • Drop in lymphocyte counts • Get q6h CBC first day, then daily • HLA typing
ARS Gastrointestinal • Seen with exposure of 600- 1000 R or higher • Depopulation of epithelial lining • In sublethal doses, presents as GI distress in 2 days • Death in 3-10 days without massive support • Treat dehydration, nausea, vomiting, diarrhea symptomatically
ARS Central Nervous System • Seen with total body exposure of 5000R • Death in hours • Other syndromes don’t have time to develop
ARS Cardiovascular • Seen with total body exposure of 2000- 5000R • Within minutes: skin burning sensation, confusion, nausea, oliting, diarrhea, LOC • Death usually in minutes to hours • Other syndromes don’t have time to develop
ARS Skin(skin doses, not whole body doses) • Seen with exposure to high doses of beta radiation • Washing off contaminants can prevent skin damage • Acute: 600 - 2000 R causes erythema • Acute: 2000-4000R causes skin breakdown in 2 weeks • Acute: > 30,000 R immediate skin blistering • Chronic: > 2000 R causes delayed and irreversible structural changes, dermatitis with increased cancer risk
References • Zajtchuk, R, ed: Textbook of military medicine part 1: military consequences of nuclear warfare. TMM Publications, 1989 • Medical management of radiation casualties, Second Edition 2003 www.afrri.usuhs.mil • Mettler, FA, Kelsey, CA & Ricks, RC: Medical management of radiation accidents Boca Raton: CRC Press 1990 • Ricks, RC, Berger, ME and O’Hara, FM: The medical basis for radiation accident preparedness. New York: Parthenon Publishing 2002