DTIC ADA614600: Venous Thromboembolism during Combat Operations: A 10-y Review

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by  Defense Technical Information Center

journal of surgical research 187 (2014) 625 630
Availableonlineatwww.sciencedirect.com
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journal homepage: www.JournalofSurgicalResearch.com
Venous thromboembolism during combat
operations: a 10-y review
Tara N. Hutchison, Chad A. Krueger, MD, John S. Berry, MD,
James K. Aden, PhD, Stephen M. Cohn, MD,
and Christopher E. White, MD, MSc*
BrookeArmyMedicalCenter,FortSamHouston,Texas
a r t i c l e i n f o a b s t r a c t
Articlehistory: Background: This article examines the incidence of venous thromboembolism (VTE) in
Received18August2013 combatwounded,identifiesriskfactorsforpulmonaryembolism(PE),andcomparesthe
Receivedinrevisedform rateofPEincombatwithpreviouslyreportedciviliandata.
22October2013 Methods: A retrospective review was performed of all U.S. military combat casualties in
Accepted7November2013 Operation Enduring Freedom and Operation Iraqi Freedom with a VTE recorded in the
Availableonline15November2013 Department ofDefenseTrauma Registry fromSeptember2001 toJuly 2011.TheMilitary
AmputationDatabaseofallU.S.militaryamputationsduringthesame10 yperiodwasalso
Keywords: reviewed.Demographicdata,injurycharacteristics,andoutcomeswereevaluated.
Trauma Results: Among 26,634 subjects, 587 (2.2%)had a VTE. This number included 270 subjects
Combat (1.0%)withdeepvenousthrombosis(DVT),223(0.8%)withPE,and94(0.4%)withbothDVT
Venousthromboembolism andPE.LowerextremityamputationwasindependentlyassociatedwithPE(oddsratio[OR],
Deepvenousthrombosis 1.70;95%confidenceinterval[CI],1.07 2.69).Atotalof1003subjectssufferedalowerex
Pulmonaryembolism tremityamputation,with174(17%)havingaVTE.Ofthese,75subjects(7.5%)werehaving
Amputation DVT,70(7.0%)werehavingPE,and29(2.9%)werefoundtohavebothaDVTandaPE.Risk
War factorsfoundtobeindependentlyassociatedwithVTEinamputeesweremultipleampu
tations(OR,2;95%CI,1.35 3.42)andabovethekneeamputation(OR,2.11;95%CI,1.3 3.32).
Conclusions:Combatwoundedareatahighriskforthromboemboliccomplicationswiththe
highestriskassociatedwithmultipleorabovethekneeamputations.
PublishedbyElsevierInc.
1. Introduction thromboembolism(VTE),whichincludedeepvenousthrom
bosis (DVT) and PE in hospitalized trauma patients, ranges
Tissue injury in conjunction with both the inflammatory fromlessthan1%e58%dependingonthepopulationstudied,
responseandthedelayedinhibitionoffibrinolysisplacesthe detectionmethods(i.e.,venography,colorflowDoppler,and
traumapatientatincreasedriskforvenousthromboembolic spiral computer tomography), prophylactic anticoagulation
events,which are major sourcesof morbidityand mortality strategiesused,andotherfactors[2e13].Thisvariabilitybe
in this population [1]. In fact, after surviving the first 24 h, tweenstudiesmakesitdifficulttoassesstheriskofVTEforan
pulmonary embolism (PE) is the third most common cause individualpatientandapplytreatmentstrategiestooptimize
of death after trauma [2e5]. The incidence of venous care. This is particularly true for combat casualties, which
ThisworkwaspresentedattheeighthAnnualAcademicSurgicalCongress,NewOrleans,LA,onFebruary5 7,2013.
* Correspondingauthor.BrookeArmyMedicalCenter,3851RogerBrookeDr,FortSamHouston,TX78234.Tel.:þ12109163301;fax:þ1
2102710830.
E mailaddress:[email protected](C.E.White).
0022 4804/$ seefrontmatterPublishedbyElsevierInc.
http://dx.doi.org/10.1016/j.jss.2013.11.008
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1. REPORT DATE 2. REPORT TYPE 3. DATES COVERED
01 APR 2014 N/A -
4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER
Venous thromboembolism during combat operations: a 10-y review
5b. GRANT NUMBER
5c. PROGRAM ELEMENT NUMBER
6. AUTHOR(S) 5d. PROJECT NUMBER
Hutchison T. N., Krueger C. A., Berry J. S., Aden J. K., Cohn S. M.,
5e. TASK NUMBER
White C. E.,
5f. WORK UNIT NUMBER
7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION
United States Army Institute of Surgical Research, JBSA Fort Sam REPORT NUMBER
Hosuton, TX
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626 journal of surgical research 187 (2014) 625 630
have different and oftentimes more severe injuries, require amputationlevel,andabriefnarrativehistoryoftheinjuring
longer transportation times with extended immobilization, event and acute medical care provided. Additional informa
andfrequentlycannotreceivepharmacologicprophylaxisof tionpertainingtotheinjuryandtreatmentofeachamputee
VTEbecauseoftheriskofbleeding.Thepurposeofthisstudy wasobtainedfromtheDoDTR.
was to determine the incidence of VTEs among combat ca
sualties injured during wartime to better predict those pa 2.2. Statisticalanalysis
tients who are at increased risk of VTE (DVT and PE).
Additionally,wehypothesizedthat(1)theincidenceofVTEin Variables for the univariate analysis were identified from
combatwoundedishigherthaninciviliantrauma,and(2)the previous risk factors present in the civilian population and
riskfactorsforVTEbetweenmilitaryandciviliancohortsare thoseuniquetoatheaterofwar(e.g.,explosivemechanismof
different. injury and theater of operation) [6,12e15]. Continuous vari
ableswerereportedasmedians(withinterquartilerangesthe
25thand75thpercentiles)andcomparedusingStudentt test
2. Methods orManneWhitneytest,whicheverismostappropriate.Cate
goricalvariableswerereportedasnumbersandpercentages
This retrospective study was conducted under a protocol andwerecomparedusingc2 test.Indefiningindependentrisk
approved by the San Antonio Military Medical Center Insti factorsforVTE,significancewassetatP<0.05.Riskfactors
tutional Review Board. The Department of Defense Trauma associated with PE were entered into a logistic regression
Registry(DoDTR)(FortSamHouston,TX),formerlyknownas model. Backward elimination was then applied so that only
the Joint Theater Trauma Registry, was queried for data on factorswithPvalues<0.20wereincludedinthefinalmodel.A
United States military service members who were injured logisticregressionmodel,followed by backward elimination
duringOperationEnduringFreedom(OEF)orOperationIraqi wasalsousedforamputeeriskfactoridentification.
Freedom (OIF) and sustained a VTE (DVT and PE) from
September 2001 through July 2011. This includes all VTEs
identified at level III (Combat Support Hospital in theater of 3. Results
war), level IV (Landstuhl Regional Medical Center [LRMC],
regionalevacuationcenterinLandstuhl,Germany),andlevel From September 2001 through July 2011, there were 26,634
V (participating military tertiary care centers within the subjectsavailableforanalysis;587subjects(2.2%)developeda
UnitedStates).Patientsreportedaskilledinactionordeadon VTE(Fig.1).Ofthese,therewere270subjects(1.0%)withDVT,
arrivalwereexcludedfromanalysis.PatientswithVTEswere 223 (0.8%) with PE, and 94 (0.4%) with both DVT and PE. Of
identified using International Classification of Disease, ninth those who developed VTE, 12% were identified in theater,
edition,andAbbreviatedInjuryScale(AIS)2005injurycodes. whereas36%and52%wereidentifiedatlevelIV(LRMC)and
Complications at all facilities were identified using Interna levelVtertiarycarecentersintheUnitedStates,respectively.
tionalClassification of Disease, ninth editioncodes. The domi Overall,ahigherpercentageofcasualtieswhodevelopedVTE
nantinjurymechanismwascategorizedasexplosivedevice, had an ISS >10, were injured with an improvised explosive
gunshotwound,motorvehicleaccident,helicoptercrash,or device(IED), or suffereda penetrating injury(Table 1). After
machinery and equipment. Injury Severity Score (ISS), AIS, univariate analysis (Table 2), risk factors associated with PE
injurydate,andcomplicationswhenintheaterwerecollected includedinjuryinOIFandbluntmechanismofinjury.Ofthese
fromtheDoDTR. subjectswithaPE,3.5%died.Duringmultivariateanalysis,the
only independent risk factor for PE was lower extremity
2.1. Dataanalysis amputation(Table3).
Atotalof1003of26,634combatcasualties(3.7%)suffered
A listof VTE risk factorswasassembledby military doctors lower extremity amputations; 174 (17.3%) of these subjects
with experience with VTE during OEF and OIF and included with lower extremity amputations developed VTEs (Fig. 1).
previouslyidentifiedriskfactorsfromciviliantraumastudies
[2,12].Foreachriskfactor,subjectswithaDVTwerecompared
against those patients with a PE and an odds ratio was
calculated.Oncealowerextremityamputationwasidentified
as the risk factor for PE, then demographics, injury charac
teristic,andamputationlevelwerecollectedfromtheMilitary
Amputation Database(MAD) (ExtremityTrauma and Ampu
tationCenterofExcellence,FortSamHouston,TX).TheMAD
containsdemographicinformationonallUnitedStatesmili
tarypersonnelwhounderwentamputationsbetweenOctober
1, 2001 and July 30, 2011. MAD is not specific to any service
branch or treatment facility and defines a major extremity
amputationasanamputationproximaltothecarpalortarsal
bonesofalimb[14].Thefollowingdatawereextractedfrom
the MAD for each service member sufferingan amputation:
age at injury, date of injury, date of first amputation, Fig.1eVTEconsortdiagram.

630 journal of surgical research 187 (2014) 625 630
[4] O’MalleyKF,RossSE.Pulmonaryembolisminmajortrauma extremityamongthermallyinjuredpatientsdeterminedby
patients.JTrauma1990;30:748. duplexsonography.JTrauma2003;55:1162.
[5] GoldhaberSZ,BounameauxH.Pulmonaryembolismand [13] KnudsonMM,CollinsJA,GoodmanSB,McCroryDW.
deepveinthrombosis.Lancet2012;379:1835. Thromboembolismfollowingmultipletrauma.JTrauma
[6] KnudsonMM,IkossiDG,KhawL,MorabitoD,SpeetzenLS. 1992;32:2.
Thromboembolismaftertrauma:ananalysisof1602 [14] KruegerCA,WenkeJC,FickeJR.Tenyearsatwar:
episodesfromtheAmericanCollegeofSurgeonsNational comprehensiveanalysisofamputationtrends.JTrauma
TraumaDataBank.AnnSurg2004;240:490. AcuteCareSurg2012;73(6Suppl5):S438.
[7] KadyanV,ClinchotDM,MitchellGL,ColachisSC. [15] StawickiSP,GrossmanMD,CipollaJ,etal.Deepvein
Surveillancewithduplexultrasoundintraumaticspinalcord thrombosisandpulmonaryembolismintrauma
injuryoninitialadmissiontorehabilitation.JSpinalCord patients:anoverstatementoftheproblem?AmSurg2005;71:
Med2003;26:231. 387.
[8] GreenD,HartwigD,ChenD,SoltysikRC,YarnoldPR.Spinal [16] PaffrathT,WafaisadeA,LeferingR,etal.Venous
cordinjuryriskassessmentforthromboembolism(SPIRATE thromboembolismafterseveretrauma:incidence,risk
study).AmJPhysMedRehabil2003;82:950. factorsandoutcome.Injury2010;41:97.
[9] BrittSL,BarkerDE,MaxwellRA,CirauloDL,RichartCM, [17] HolleyAB,PetteysJD,HolleyPR,HolleyPR,CollenJF.
BurnsRP.Theimpactofpelvicandlowerextremityfractures Thromboprophylaxisandvenousthromboembolismratesin
ontheincidenceoflowerextremitydeepveinthrombosisin soldierswoundedinoperationenduringfreedomand
high risktraumapatients.AmSurg2003;69:459. operationIraqifreedom.Chest2013;144:966.
[10] MajorKM,WilsonM,NishiGK,etal.Theincidenceof [18] GillernSM,SheppardFR,EvansKN,etal.Incidence
thromboembolisminthesurgicalintensivecareunit.Am ofpulmonaryembolismincombatcasualties
Surg2003;69:857. withextremityamputationsandfractures.JTrauma2011;71:
[11] PageRB,SpottMA,KrishnamurthyS,TaleghaniC, 607.
ChinchilliVM.Headinjuryandpulmonaryembolism:a [19] JointTheaterTraumaSystemClinicalPracticeGuidelines
retrospectivereportbasedonthePennsylvaniaTrauma forthepreventionofdeepveinthrombosis.Retrieved
Outcomesstudy.Neurosurgery2004;54:143. December31,2013,fromhttp://www.usaisr.amedd.army.
[12] WibbenmeyerLA,HoballahJJ,AmelonMJ,etal.The mil/assets/cpgs/Prevention of Deep Venous Thrombosis
prevalenceofvenousthromboembolismofthelower 24 Apr 12.pdf.