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Medical Response to Nuclear and Radiological Events. Cham Dallas, PhD Director CDC Center for Mass Destruction Defense. Overview. Nuclear scenario effects Radiation injury Acute radiation syndrome Mass burn casualties External contamination Internal contamination
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Medical Response to Nuclear and Radiological Events Cham Dallas, PhD DirectorCDC Center for Mass Destruction Defense
Overview • Nuclear scenario effects • Radiation injury • Acute radiation syndrome • Mass burn casualties • External contamination • Internal contamination • Pharmaceutical intervention strategies
Question Which of the following are most likely to occur and result in significant casualties? A. Nuclear power plant release B. Improvised nuclear devise C. Conventional nuclear weapon D. “Dirty” bomb
Potential Nuclear/Radiological Hazards in the U.S. • Simple radiological device • “Dirty” conventional bomb • Improvised nuclear device (IND) • 1 kT “suitcase nuke” • Ballistic missile attack • 250 kT nuclear weapon: “city killer” Plutonium
Diversion of Nuclear Weapons 50 –100 1 kT “suitcase” nuclear weapons are unaccounted for. The Threat of Nuclear Diversion. Statement for the Record by John Deutch, Director of the Central Intelligence to the Permanent Subcommittee on Investigations of the Senate Committee on Government Affairs, 20 March 1996.
Energy Partition Standard Fission/Fusion Thermal 35% Blast 50% 10% Fallout InitialRadiation 5% AFRRI, Medical Effects of Nuclear Weapons, “Blast and ThermalEffects” Lecture, 1990.
White House Capitol Lincoln Memorial The Mall Washington Monument Potomac River Scenario: Washington Mall
Effective Range for Blast Energy AFRRI, Medical Effects of Nuclear Weapons, “Blast and Thermal Effects” Lecture, 1990.
Effective Range for Thermal Energy 1 kT Weapon AFRRI, Medical Effects of Nuclear Weapons, “Blast and Thermal Effects” Lecture, 1990.
Safe Separation Distances for Eye Injuries 1 kT Weapon AFRRI, Medical Effects of Nuclear Weapons, “Blast and Thermal Effects” Lecture, 1990.
Atlanta SSE Med Wind 250 kT Fatalities Probability of Fatality (Default Plot) Time: 32 days, 0.0 hours Mean Probability of Fatality Expected Prob Population 90% 0.9 455,934 50% 0.5 661,169 10% 0.1 886,681 Fatality Possible (w/meander) Expected Prob Population 90% 0.9 455,934
New York: 250 kT Nuclear Detonation Mortality Probability 3.9m Affected Red 90% Lt Brown 80% Yellow 70% Green 60% Pale Blue 50% Dark Blue 40% Lt Purple 30% Dk Purple 20% Dk Pink 10% Lt Pink 1%
What Is Fallout? • A complex mixture of more than 200 different isotopes of 36 elements • 2 oz of fission products formed for each kT of yield • Size <1 micron to several mm
Question The risk from delayed fallout that is dispersed long distances (>100 miles) still has a devastating impact on public health. A. True B. False
Early Fallout • That which reaches the ground during the first 24 hours after detonation • Early fallout fraction 50 –70% of total radioactivity • Highest degree of fallout risk
Delayed Fallout • Arrives after the first day, very fine invisible particles which settle in low concentrations over a considerable portion of the earth’s surface • 40% of total radioactivity • Much lower degree of risk relative to early fallout
Bikini Atoll (1 March 1954) Radioactive Contamination • 15 mT thermonuclear detonation fallout • Population affected: 300 in public domain • Int/Ext contamination • Local radiation injury • Mild ARS • Thyroid injury Radiodermatitis
Ionizing Radiation Radiation that consists of directly or indirectly ionizing particles or photons Alpha Beta Gamma Neutron 1 m concrete
* * * * * * * * Radiation Exposure Types External Contamination Internal Contamination Irradiation
Acute Radiation Syndrome • Systemic effects of radiation • Prodromal • Hematologic • Gastronintestinal • Pulmonary • Cutaneous • Neurovascular • Combined injury
Prodromal Component (0.5–3 Gy and higher) • Immediate effect of cell membrane damage • Onset of nausea, vomiting, diarrhea • Mediated neurologically by the parasympathetic system
Respiratory Component(5–310 Gy and higher) • Sensitive from highly vascular tissue • Endothelial cells • Type II alveolar cell • Effect is dose-rate related • Pneumonitis • Fibrosis Healthy lung Pneumonitis
Radiation Skin Injury • 0.75 Gy Hair follicles change • 3 Gy Epilation • 6 Gy Erythema • 10 Gy Dry desquamation • 20 Gy Wet desquamation (transepithelial injury) Erythema
Distribution of Injuries in aNuclear Detonation Single injuries (30%–40%) Combined injuries (65%–70%) Wounds + Burns Wounds + 5% Irradiation Irradiation 5% 15–20% Burns + Wounds + Irradiation 20% Burns 15–20% Burns + Wounds < 5% Irradiation 40% Data from Walker RI, Cerveny TJ Eds., Medical Consequences of Nuclear Warfare, TMM Publications, Falls Church, 1989. p 11.
Absolute lymphocyte count over 48 hours Confirms significant radiation exposure Andrews Lymphocyte Nomogram From Andrews GA, Auxier JA, Lushbaugh CC: The Importance of Dosimetry to the Medical Management of Persons Exposed to High Levels of Radiation. In Personal Dosimetry for Radiation Accidents. Vienna, International Atomic Energy Agency, 1965, pp 3- 16
Priorities in Combined-Injury Triage- Radiation Doses Conventional Triage Changes in Expected Triage (No Radiation Exists) Following Radiation Exposure <1.5Gy 1.5–4.5Gy >4.5Gy >3 hr 1–3 hr <1 hr onset onset onset Immediate Immediate Immediate Expectant Delayed Delayed Expectant Expectant Minimal Minimal Expectant Expectant Expectant Expectant Expectant Expectant Modified from Medical Consequences of Nuclear Warfare, 1989, p. 39
Decontamination Equipment • Hospital surgical gown (waterproof) • Cap, face shield, booties (waterproof) • Double gloves (inner layer taped) • Pencil dosimeters, TLDs, survey meters • Drapes • Plastic bags • Butcher paper • Large garbage cans • Radiation signs and tape
Question Which of the following is the best decontamination agent? A. Dry removal B. Bleach C. Soap & water D. Waterless cleanser
Decon Agents: 1 • Dry removal • Soap/shampoo • Household bleach 1:10 (sodium hypochlorite) • Waterless cleansers • Povidone-iodine • Lava soap • Cornmeal/Tide 50:50 • Vinegar (32P) or club soda • Toothpaste
Internal Contamination Involves 4 Stages • Deposition along route of entry • Translocation • Deposition in target organ • Clearance
Therapeutic Interventions • Plutonium/transuranics: DTPA • Cesium: insoluble Prussian Blue • Uranium: alkalinization of urine • Radioiodine: radiostable iodine • Tritium: radiostable water
…is for good men and women to do nothing. All that is necessary for the triumph of evil…