radiation injury

RADIATION INJURIESRADIATION INJURIES

RADIATION INJURIESRADIATION INJURIES Ionizing radiation: Radiation Ionizing radiation: Radiation

that occurs when atoms have that occurs when atoms have 1 or more electrons ejected 1 or more electrons ejected owing to interactions with x- or owing to interactions with x- or gamma rays or with alpha or gamma rays or with alpha or beta particles or neutrons.beta particles or neutrons.

Penetrating radiation: x-, Penetrating radiation: x-, gamma rays, neutronsgamma rays, neutrons

Non-penetrating radiation: Non-penetrating radiation: alpha, betaalpha, beta


Humans affected Humans affected externally and/or externally and/or internally by internally by radiation.radiation.

1 Roentgen = 1 1 Roentgen = 1 rad = 1 rem =10 rad = 1 rem =10 mGy = 10 mSv.mGy = 10 mSv.


Radiobiological principlesRadiobiological principles– Radiation targets water molecules in cells Radiation targets water molecules in cells

H2O ionized Resulting free radicals H2O ionized Resulting free radicals are highly reactive and rapidly interact with are highly reactive and rapidly interact with other cellular molecules (DNA, mRNA, other cellular molecules (DNA, mRNA, proteins).proteins).


Radiobiological principlesRadiobiological principles– Severity of biological effects due to:Severity of biological effects due to:

DoseDose Dose rateDose rate ShieldingShielding Energy (degree affects penetration)Energy (degree affects penetration)


Radiation pathophysiologyRadiation pathophysiology– Radiosensitivity varies directly with rate Radiosensitivity varies directly with rate

of cell proliferation (RBCs, G.I. Mucosa of cell proliferation (RBCs, G.I. Mucosa cells).cells).

– Radiosenstivity varies directly with Radiosenstivity varies directly with number of future divisions (stem cells).number of future divisions (stem cells).

– Radiosensitivity varies inversely with Radiosensitivity varies inversely with degree of morphologic and functional degree of morphologic and functional differentiation ( exception: lymphocyte).differentiation ( exception: lymphocyte).


Types of radiation releasesTypes of radiation releases– Radiation dispersal device Radiation dispersal device

(RDD)(RDD)– Nuclear reactor accidentNuclear reactor accident– Industrial/medical source Industrial/medical source

accidentaccident– Nuclear weapon detonationNuclear weapon detonation

Thermal, blast, radiation traumaThermal, blast, radiation trauma Fallout (radioactive particles of Fallout (radioactive particles of

dust)dust)

RADIATION INJURIESRADIATION INJURIES– GyGy Signs & SymptomsSigns & Symptoms

0.05-0.25 0.05-0.25 Asymptomatic.Asymptomatic. 0.50-0.750.50-0.75 Asymptomatic; few with decreased WBC, platelets.Asymptomatic; few with decreased WBC, platelets. 0.75-1.250.75-1.25 Within 2 days, 10-20% with nausea, vomiting, Within 2 days, 10-20% with nausea, vomiting,

fatigue; some fatigue; some with mild WBC/platelet with mild WBC/platelet depressiondepression

1.25-2.01.25-2.0 Symptomatic; most with hematologic changes; Symptomatic; most with hematologic changes; lymphocytes lymphocytes drop 50% within 48 hrs.drop 50% within 48 hrs.

2.5-3.52.5-3.5Serious; 50% mortality if untreated; lymphocytes drop Serious; 50% mortality if untreated; lymphocytes drop 75% 75% within 48 hrs.within 48 hrs.

5+5+ GI subsyndrome within 2 weeks; death occurs in mostGI subsyndrome within 2 weeks; death occurs in most 50+50+ CV, GI, CNS subsyndromes with death within 24-72 hrs.CV, GI, CNS subsyndromes with death within 24-72 hrs.


3 Types of radiation exposure3 Types of radiation exposure– IrradiationIrradiation– Internal contaminationInternal contamination– External contaminationExternal contamination


Acute Radiation Syndrome (ARS)Acute Radiation Syndrome (ARS)– Responsible for most deaths during Responsible for most deaths during

first 60 days post-exposure.first 60 days post-exposure.– Course affected by age, pre-existing Course affected by age, pre-existing

health and nutritional status, health and nutritional status, concomitant illness/injury.concomitant illness/injury.

– Composed of 3-4 subsyndromes Composed of 3-4 subsyndromes which are sequential.which are sequential.


Acute Radiation Syndrome (ARS)Acute Radiation Syndrome (ARS)– SubsyndromesSubsyndromes

Hematopoietic (1-5 Gy)Hematopoietic (1-5 Gy) Gastrointestinal (6-30 Gy)Gastrointestinal (6-30 Gy) Cardiovascular (>30 Gy)Cardiovascular (>30 Gy) Neurologic (>30 Gy)Neurologic (>30 Gy)


Acute Radiation Syndrome (ARS)Acute Radiation Syndrome (ARS)– HematopoieticHematopoietic

All blood stem cells undergo radiation-All blood stem cells undergo radiation-induced cell death (lymphocytes, induced cell death (lymphocytes, granulocytes, thrombocytes, & RBC granulocytes, thrombocytes, & RBC precursors)precursors)

PancytopeniaPancytopenia Sepsis usual cause of deathSepsis usual cause of death HemorrhageHemorrhage Recovery: Months-yearsRecovery: Months-years


Acute Radiation Syndrome Acute Radiation Syndrome (ARS)(ARS)– GastrointestinalGastrointestinal

Targets: G.I.stem cells, lymphocytes Targets: G.I.stem cells, lymphocytes in Peyer’s patchesin Peyer’s patches

Mucosal lining sloughs, mucosal Mucosal lining sloughs, mucosal integrity damaged, mucosal integrity damaged, mucosal hemorrhage, exudation, ulceration, hemorrhage, exudation, ulceration, third spacing, fluid/electrolyte third spacing, fluid/electrolyte imbalance, paralytic ileus, impaired imbalance, paralytic ileus, impaired nutritional absorption, bacterial nutritional absorption, bacterial translocation (sepsis)translocation (sepsis)


Acute Radiation Syndrome (ARS)Acute Radiation Syndrome (ARS)– Cardiovascular/NeurologicCardiovascular/Neurologic

MixedMixed Burning of skin within Burning of skin within minutesminutes Pyrexia, ataxia, decreased higher cortical and Pyrexia, ataxia, decreased higher cortical and

motor function, hypotension, increased motor function, hypotension, increased intracranial pressures within intracranial pressures within minutes to hoursminutes to hours of exposureof exposure

Necropsy: Microvascular & endothelial Necropsy: Microvascular & endothelial damage, focal brain hemorrhage & necrosis, damage, focal brain hemorrhage & necrosis, white matter edema, demyelination white matter edema, demyelination


Acute Radiation SyndromeAcute Radiation Syndrome– Four stagesFour stages– 1: Prodrome1: Prodrome

– Initial symptoms: Important to observe, time, and Initial symptoms: Important to observe, time, and documentdocument

– Time of onset is inversely related to dose receivedTime of onset is inversely related to dose received– Anorexia, weakness, fatigability: Typical/nonspecificAnorexia, weakness, fatigability: Typical/nonspecific– CV/CNS S&S: OminousCV/CNS S&S: Ominous– Nausea, vomiting, diarrhea (possible bloody): Nausea, vomiting, diarrhea (possible bloody):

Important to noteImportant to note Mild; >2 hr. & < 24 hr. = <2 GyMild; >2 hr. & < 24 hr. = <2 Gy


Acute Radiation SyndromeAcute Radiation Syndrome– Four stagesFour stages– 2: Latent period2: Latent period

– Inversely related to doseInversely related to dose– At lower doses: Essentially symptom At lower doses: Essentially symptom

free; mild fatigue; prone to infection free; mild fatigue; prone to infection and delayed wound healing.and delayed wound healing.


Prodromal/Latency Periods as a Prodromal/Latency Periods as a Function of DoseFunction of Dose

DoseDose Gy Gy Onset Onset h h Duration Duration h h LatencyLatency 0.5-2.0 6 or > <24 3 wks or >0.5-2.0 6 or > <24 3 wks or > 2.0-3.5 2-6 12-24 2-3 wks2.0-3.5 2-6 12-24 2-3 wks 3.5-5.5 1-2 24 1-2.5 wks3.5-5.5 1-2 24 1-2.5 wks >5.5 < 1 48 2-4 days>5.5 < 1 48 2-4 days


Acute Radiation SyndromeAcute Radiation Syndrome– Four StagesFour Stages– 3: Manifest Illness3: Manifest Illness

– Prodromal symptoms recurProdromal symptoms recur– Subsyndrome specific effects developSubsyndrome specific effects develop– Can last for several weeksCan last for several weeks– Requires intensive monitoring and Requires intensive monitoring and

carecare


Acute Radiation SyndromeAcute Radiation Syndrome– Four StagesFour Stages– 4: Recovery4: Recovery

GI epithelium replacedGI epithelium replaced Hematopoietic elements return to normalHematopoietic elements return to normal May take years to recoverMay take years to recover


Miscellaneous conditionsMiscellaneous conditions– SkinSkin

Initial transient erythema Initial transient erythema for few daysfor few days

Secondary erythema Secondary erythema progressing to blisters to progressing to blisters to ulcers ulcers

– within 1 monthwithin 1 month– The greater the exposure the The greater the exposure the

earlier the manifestationsearlier the manifestations


Miscellaneous conditionsMiscellaneous conditions– PulmonaryPulmonary

ChernobylChernobyl Acute radiation pulmonitisAcute radiation pulmonitis Severe SOB + significant crepitusSevere SOB + significant crepitus Significant mortality from hypoxic coma Significant mortality from hypoxic coma

within 2-4 wks laterwithin 2-4 wks later


Lymphocyte counts in Humans 24-Lymphocyte counts in Humans 24-48 Hours After Radiation Exposure48 Hours After Radiation Exposure

Lymphocyte Count (x1000/mm3) Dose Range (Gy)Lymphocyte Count (x1000/mm3) Dose Range (Gy) 3.03.0 <0.25<0.25 1.2-2.01.2-2.0 1-21-2 0.4-1.0.4-1.2 2 2.0-3.52.0-3.5 0.1-0.4 0.1-0.4 3.5-5.53.5-5.5 <0.1<0.1 >5.5>5.5


Mass Casualty IncidentsMass Casualty Incidents– Standard MCI + Radiation Injuries: Standard MCI + Radiation Injuries:

Standard Triage. ARS victims only Standard Triage. ARS victims only tagged “DELAYED”tagged “DELAYED”

– Radiation MCI onlyRadiation MCI only 3 triage categories:3 triage categories:

– Radiation injury unlikelyRadiation injury unlikely– Radiation injury probableRadiation injury probable– Radiation injury severeRadiation injury severe


– Radiation MCI categories:Radiation MCI categories: – Radiation injury unlikelyRadiation injury unlikely

Absence of nausea, vomiting, diarrheaAbsence of nausea, vomiting, diarrhea

– Radiation injury probableRadiation injury probable Presence of symptoms, timing, severity, Presence of symptoms, timing, severity,

durationduration

– Radiation injury severeRadiation injury severe Presence of hyperthermia, hypotension, Presence of hyperthermia, hypotension,

prompt erythema, CNS dysfunctionprompt erythema, CNS dysfunction

RADIATION INJURIES RADIATION INJURIES CHERNOBYL TRIAGECHERNOBYL TRIAGE

FIRST DEGREEFIRST DEGREE PRODROME:PRODROME: >3H>3H LYMPHS (3-6D):LYMPHS (3-6D): 600-1000600-1000 SKIN BURNS:SKIN BURNS: SLIGHTSLIGHT TBI DOSE:TBI DOSE: 1-2 Gy1-2 Gy SURVIVALSURVIVAL PROBABLEPROBABLE

SECOND DEGREESECOND DEGREE PRODROME:PRODROME: 1-3H1-3H LYMPHS (3-6D):300-500LYMPHS (3-6D):300-500 SKIN BURNS:SKIN BURNS: SLIGHTSLIGHT TBI DOSE:TBI DOSE: 2-4 Gy2-4 Gy SURVIVAL:SURVIVAL: POSSIBLEPOSSIBLE

THIRD DEGREETHIRD DEGREE PRODROME:PRODROME: 1/2-1H1/2-1H LYMPHS (3-6D):100-200LYMPHS (3-6D):100-200 SKIN BURNS:SKIN BURNS: SEVERESEVERE ENTERITIS:ENTERITIS: -------------- TBI DOSE:TBI DOSE: 4.2-6.3Gy4.2-6.3Gy SURVIVAL:SURVIVAL: PROBABLE WITH PROBABLE WITH

THERAPYTHERAPY

FOURTH DEGREEFOURTH DEGREE PRODROME:PRODROME: <1/2H<1/2H LYMPHS (3-6D):<100LYMPHS (3-6D):<100 SKIN BURNS:SKIN BURNS: 40-90%40-90% ENTERITIS:ENTERITIS: 7-9D7-9D TBI DOSE:TBI DOSE: >6-12 Gy>6-12 Gy SURVIVAL:SURVIVAL: UNLIKELYUNLIKELY


Contamination issuesContamination issues– Decontamination Decontamination

performedperformed To reduce risk of To reduce risk of

contaminating personnel contaminating personnel and environmentand environment

To reduce risk of internal To reduce risk of internal contamination of victimcontamination of victim


Contamination issuesContamination issues No medical personnel No medical personnel

have ever received an have ever received an exposure anywhere near exposure anywhere near the degree to cause the degree to cause radiation effects.radiation effects.


Contamination issuesContamination issues 95% of decon 95% of decon occurs with:occurs with:– Removal of patient’s Removal of patient’s

clothingclothing– Soap & waterSoap & water


Contamination issuesContamination issues– Portals of entry for internal Portals of entry for internal

contaminationcontamination WoundsWounds InhalationInhalation IngestionIngestion


Decon proceduresDecon procedures– Environmental/personal protectionEnvironmental/personal protection– Attend to medical problems firstAttend to medical problems first– Remove victim’s clothesRemove victim’s clothes– Shower, soap/waterShower, soap/water– Tape and lift contaminant materialTape and lift contaminant material– Water/bleach or citric acid or EDTAWater/bleach or citric acid or EDTA– Water/mild abrasiveWater/mild abrasive– Wrap/cover areas not deconned adequately Wrap/cover areas not deconned adequately

and allow sweat/skin sloughing to deconand allow sweat/skin sloughing to decon


Decon proceduresDecon procedures– Monitor effectiveness after Monitor effectiveness after

every decon procedureevery decon procedure– Contaminated wounds to Contaminated wounds to

be irrigatedbe irrigated– Surgical debridement of Surgical debridement of

wounds possiblewounds possible


Decon procedures for Decon procedures for environs/personnelenvirons/personnel– Gowns, cap, gloves, mask, shoecoversGowns, cap, gloves, mask, shoecovers– Decrease air flowDecrease air flow– Cover floor, walls (plastic, brown paper rolls)Cover floor, walls (plastic, brown paper rolls)– Contaminated clothes in plastic/paper bagsContaminated clothes in plastic/paper bags– Avoid splashingAvoid splashing– Monitor before moving out of areaMonitor before moving out of area– Personal dosimetersPersonal dosimeters– Drums to contain effluentDrums to contain effluent– Restrict entryRestrict entry


Contamination issuesContamination issues– 4 means of reducing risk of internal 4 means of reducing risk of internal

contamination:contamination: Reduce intake from inhalation, ingestion, or Reduce intake from inhalation, ingestion, or

absorption from woundsabsorption from wounds Decrease uptake through use of Decrease uptake through use of

stomach/lung lavage, emetics, antacidsstomach/lung lavage, emetics, antacids Reduce deposition of isotopes in an organ (KI)Reduce deposition of isotopes in an organ (KI) Increase rate of elimination through chelating Increase rate of elimination through chelating

agents, diuresis, laxatives agents, diuresis, laxatives


Contamination monitorsContamination monitors– DirectDirect

Whole-body radiation Whole-body radiation counters, thyroid scanners, counters, thyroid scanners, wound-monitoring wound-monitoring instrumentsinstruments

– IndirectIndirect Bioassay sampling: Nasal Bioassay sampling: Nasal

swabs, urine/feces swabs, urine/feces samples samples


DMAT functionsDMAT functions– Obtain on-site Radiation Safety OfficerObtain on-site Radiation Safety Officer– Team Commander remains above RSOTeam Commander remains above RSO– May work in warm/cold zones as long as no May work in warm/cold zones as long as no

further radiation exposurefurther radiation exposure– Obtain and train with standard radiation Obtain and train with standard radiation

protocolsprotocols– Treat Medical/Surgical matters first before Treat Medical/Surgical matters first before

Radiation mattersRadiation matters– Recognize psychogenic factorRecognize psychogenic factor


DMAT functionsDMAT functions– Irradiated victimsIrradiated victims

Recognize no team dangerRecognize no team danger Treat based on exposure protocolsTreat based on exposure protocols Assess and document signs/symptomsAssess and document signs/symptoms Rule out contaminationRule out contamination Appropriate triageAppropriate triage

– No prodrome: Eventual release No prodrome: Eventual release – CV/CNS prodrome: Palliative measuresCV/CNS prodrome: Palliative measures– Probable exposure: Eventual transport Probable exposure: Eventual transport


DMAT functionsDMAT functions– Contaminated victimsContaminated victims

Recognize no team dangerRecognize no team danger Remember to treat conventional injuries Remember to treat conventional injuries

firstfirst Minimize internal contaminationMinimize internal contamination Remove external contaminationRemove external contamination Appropriate triage and transportAppropriate triage and transport


BibliographyBibliography– Reeves GI: Radiation Injuries. Critical Care Clinics Vol.15, April, 1999Reeves GI: Radiation Injuries. Critical Care Clinics Vol.15, April, 1999– Voelz GZ: Radiation Injury. Textbook of Emergency Medicine, SchwartzVoelz GZ: Radiation Injury. Textbook of Emergency Medicine, Schwartz– Virtual Naval Hospital: External Irradiation. Virtual Naval Hospital: External Irradiation.

www.vnh.org/BUMEDINST6470.10A/ExtIrradiation.htmlwww.vnh.org/BUMEDINST6470.10A/ExtIrradiation.html– Virtual Naval Hospital: External Contamination. Virtual Naval Hospital: External Contamination.

www.vnh.org/BUMEDINST6470.10A/ExtContamination.htmlwww.vnh.org/BUMEDINST6470.10A/ExtContamination.html– Virtual Naval Hospital: Wound Contamination. Virtual Naval Hospital: Wound Contamination.

www.vnh.org/BUMEDINST6470.10A/WoundCont.htmlwww.vnh.org/BUMEDINST6470.10A/WoundCont.html– Virtual Naval Hospital: Internal Contamination. Virtual Naval Hospital: Internal Contamination.

www.vnh.org/BUMEDINST6470.10A/IntCont.htmlwww.vnh.org/BUMEDINST6470.10A/IntCont.html– Virtual Naval Hospital:Neutron Exposure. Virtual Naval Hospital:Neutron Exposure.

www.vnh.org/BUMEDINST6470.10A/NeutronExp.htmlwww.vnh.org/BUMEDINST6470.10A/NeutronExp.html– Fong F, Schrader DC: Radiation Disasters and Emergency Department Fong F, Schrader DC: Radiation Disasters and Emergency Department

Preparedness. Emergency Clinics of North America 14:349-370, 1996.Preparedness. Emergency Clinics of North America 14:349-370, 1996.

radiation injury

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