POSITION STATEMENT DEacuteCLARATION DE POSITION

International Federation for Emergency Medicine

Consensus Statement Sonography in hypotensionand cardiac arrest (SHoC) An international consensuson the use of point of care ultrasound forundifferentiated hypotension and during cardiac arrest

Paul Atkinson MB MAdagger Justin Bowra MBDaggersect James Milne MDpara David Lewis MBdagger Mike Lambert

MD Bob Jarman MB MScdaggerdaggerdaggerDaggerDagger Vicki E Noble MDsectsectparapara Hein Lamprecht MB Tim Harris

BMdaggerdaggerdaggerDaggerDaggerDagger Jim Connolly MBdaggerdagger

on behalf of the International Federation of Emergency Medicine Sonography in Hypotension

and Cardiac Arrest working group Romolo Gaspari MD PhD Ross Kessler MD Christopher Raio

MD Paul Sierzenski MD Beatrice Hoffmann MD Chau Pham MD Michael Woo MD Paul Olszynski

MD Ryan Henneberry MD Oron Frenkel MD Jordan Chenkin MD Greg Hall MD

Louise Rang MD Maxime Valois MD Chuck Wurster MD Mark Tutschka MD Rob Arntfield MD

Jason Fischer MD Mark Tessaro MD J Scott Bomann DO Adrian Goudie MB Gaby Blecher MB

Andreacutee Salter MB Michael Rose MB Adam Bystrzycki MB Shailesh Dass MB Owen Doran MB

Ruth Large MB Hugo Poncia MB Alistair Murray MB Jan Sadewasser MD

EXECUTIVE SUMMARY

This executive summary will provide a brief overview ofconsensus statements on sonography in hypotensionand cardiac arrest (SHoC) recommended by theInternational Federation for Emergency Medicine(IFEM) for use in emergency medicine (EM)

Purpose

As point of care ultrasound (PoCUS) has become anestablished tool in the initial management ofpatients with undifferentiated hypotension and duringcardiac arrest the Ultrasound Special Interest Group(USIG) of IFEM was tasked to provide consensusguidance for use in EM that was designed to be

widely implementable internationally and which wastargeted at likely etiologies as well as guiding resusci-tation The protocols were also aimed at minimizinginterruption of ongoing resuscitation A hierarchicalmodel was proposed to be developed by expert con-sensus based upon disease incidence previously pub-lished protocols and the medical literature A practicalchecklist was to be developed along with a standardizedapproach to the performance of scans based upon a ldquo4Frdquo approach fluid form function filling

Consensus approach

We summarized the recorded incidence of PoCUSfindings from two international multicentre prospectivestudies in addition to a checklist to guide clinicians

From Dalhousie University Saint John NB daggerSaint John Regional Hospital Saint John NB DaggerSydney Adventist Hospital Wahroonga Australia

sectUniversity of Sydney Sydney Australia paraFraser Health Authority Surrey BC Advocate Christ Medical Centre Oak Lawn IL daggerdaggerRoyal Victoria

Infirmary Newcastle upon Tyne UK DaggerDaggerUniversity of Teesside Middlesbrough UK sectsectUniversity Hospitals Cleveland Medical Center Cleveland

OH paraparaCase Western Reserve University School of Medicine Cleveland OH Stellenbosch University Stellenbosch South Africa daggerdaggerdaggerBarts

Health NHS Trust London UK and the DaggerDaggerDaggerQueen Mary University of London London UK

Correspondence to Dr Paul Atkinson International Federation for Emergency Medicine co Carol Reardon Executive Officer 34 Jeffcott Street

West Melbourne VIC 3003 Australia Email ifemacemorgau

copy Canadian Association of Emergency Physicians CJEM 20161-12 DOI 101017cem2016394

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incorporating PoCUS into the resuscitation of thearrested patient based on the current literature Rates ofabnormal PoCUS findings were presented to an inter-national expert panel and using this data we obtainedthe input of a panel of international experts associatedwith five professional organizations led by IFEM Usinga modified Delphi approach after three rounds of thesurvey agreement was reached on SHoC-hypotensionand SHoC-cardiac arrest protocols comprising coresupplementary and additional views for each situationemphasising the importance of clinical probability toguide the priority of scanning Agreement was alsoreached on the contents of the checklist

Recommendations

This international consensus based on prospectivelycollected disease incidence describes two Sonographyin Hypotension and Cardiac Arrest (SHoC) protocolscomprising of the stepwise clinical-indication basedapproach of Core Supplementary and AdditionalPoCUS views

The SHoC-hypotension protocol contains

Core views focusing on determining the category of shockwhether cardiogenic or non-cardiogenic and consisting of

1 Basic cardiac views (primarily the sub-xiphoid win-dow or parasternal long axis window for pericardialfluid cardiac form and ventricular function)

2 Lung views for pleural fluid and B-lines for fillingstatus and

3 Inferior vena cava (IVC) views for filling status

Supplementary views consisting of other cardiacviews with Additional views performed whereclinically indicated (eg AAA pelvic DVT)

The SHoC-cardiac arrest protocol contains

Core views limited to cardiac windows (primarily sub-xiphoid or parasternal long axis) and must beperformed during the rhythm check pause in chestcompressions without causing prolonged interruptionin chest compressions These windows should be usedto look for pericardial fluid as well as examining

Figure 1 Summary ldquotarget stylerdquo graphic for the combined SHoC protocols

Atkinson et al

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ABSTRACT

Introduction The International Federation for Emergency

Medicine (IFEM) Ultrasound Special Interest Group (USIG)

was tasked with development of a hierarchical consensus

approach to the use of point of care ultrasound (PoCUS) in

patients with hypotension and cardiac arrest

Methods The IFEM USIG invited 24 recognized international

leaders in PoCUS from emergency medicine and critical care

to form an expert panel to develop the sonography in

hypotension and cardiac arrest (SHoC) protocol The panel

was provided with reported disease incidence along with a

list of recommended PoCUS views from previously published

protocols and guidelines Using a modified Delphi methodol-

ogy the panel was tasked with integrating the disease

incidence their clinical experience and their knowledge of

the medical literature to evaluate what role each view should

play in the proposed SHoC protocol

Results Consensus on the SHoC protocols for hypotension

and cardiac arrest was reached after three rounds

of the modified Delphi process The final SHoC protocol

and operator checklist received over 80 consensus

approval The IFEM-approved final protocol recommend

Core Supplementary and Additional PoCUS views SHoC-

hypotension core views consist of cardiac lung and inferior

vena vaca (IVC) views with supplementary cardiac views and

additional views when clinically indicated Subxiphoid or

parasternal cardiac views minimizing pauses in chest

compressions are recommended as core views for

SHoC-cardiac arrest supplementary views are lung and IVC

with additional views when clinically indicated Both proto-

cols recommend use of the ldquo4 Frdquo approach fluid form

function fillingConclusion An international consensus on sonography in

hypotension and cardiac arrest is presented Future prospec-

tive validation is required

REacuteSUMEacute

Introduction Le groupe drsquointeacuterecirct particulier pour lrsquoeacutechogra-

phie de lrsquoInternational Federation for Emergency Medicine

(IFEM) srsquoest vu confier la tacircche drsquoeacutelaborer une deacutemarche

hieacuterarchique consensuelle relativement agrave lrsquoutilisation de

lrsquoeacutechographie au point de service (EPS) dans les cas

drsquohypotension ou dans les cas drsquoarrecirct cardiaque

Meacutethode Le groupe drsquointeacuterecirct a inviteacute 24 sommiteacutes en matiegravere

drsquoEPS agrave lrsquoeacutechelle internationale provenant des services de

meacutedecine drsquourgence et de soins intensifs pour former un

groupe drsquoexperts afin drsquoeacutelaborer un protocole sur lrsquoutilisation

de lrsquoeacutechographie dans les cas drsquohypotension et dans

les cas drsquoarrecirct cardiaque On a fourni au groupe drsquoexperts

lrsquoincidence des maladies concerneacutees ainsi qursquoune liste de

recommandations sur des prises de vue par EPS tireacutees de

protocoles et de lignes directrices deacutejagrave publieacutes Par la

suite on a demandeacute au groupe drsquointeacutegrer lrsquoincidence des

maladies concerneacutees leur expeacuterience clinique et leur con-

naissance de la documentation meacutedicale en la matiegravere

afin drsquoeacutevaluer selon une version modifieacutee de la meacutethode

Delphi le rocircle de chacune des prises de vue dans le protocole

SHoC (laquo Sonography in hypotension and cardiac arrest raquo)

proposeacute

Reacutesultats Le groupe en est arriveacute agrave un consensus apregraves trois

tours de sondage selon la version modifieacutee de la meacutethode

Delphi sur le protocole SHoC agrave appliquer dans les cas

drsquohypotension et dans les cas drsquoarrecirct cardiaque La version

deacutefinitive du protocole ainsi que la liste de veacuterification des

opeacuterateurs ont eacuteteacute approuveacutees apregraves avoir fait lrsquoobjet drsquoun

consensus plus de 80 des membres Des prises de vue par

EPS diviseacutees en cateacutegories de base suppleacutementaire et

additionnelle sont recommandeacutees dans le protocole deacutefinitif

approuveacute par lrsquoIFEM Les prises de vue de base dans les cas

drsquohypotension comprennent des clicheacutes du cœur des

poumons et de la veine cave infeacuterieure (VCI) compleacuteteacutes par

ventricular form (eg right heart strain) and function(eg asystole versus organized cardiac activity)

Supplementary views consisting of lung (for slidingor fluid) and IVC views with Additional views such asconfirmation of endotracheal tube placement or exclu-sion of aortic aneurysm performed when clinicallyindicated

An operational checklist for the use of PoCUS duringcardiac arrest is provided and includes the following keysteps

1 Team briefing2 Preparing the ultrasound machine prior to patient

arrival (if time permits)3 Performing the scan during breaks in CPR4 Reviewing the images during CPR

5 Clinical decision making and interventions based onPoCUS findings and reassessment

6 Completion of scanning7 Post-resuscitation actions

These protocols are focused to direct the clinician toperform views that are clinically indicated which aims toimprove efficiency and reduce the frequency of poten-tially distracting incidental positive findings that canaccompany the current ldquoone size fits allrdquo standard pro-tocols Figure 1 helps to conceptualize the hierarchicalcoresupplementaryadditional views approach of theSHoC algorithms This clarifies the essential views forhypotension and cardiac arrest as well as demonstratingthe foundational role that the ldquo4Frdquo approach offluid form function and filling plays in the SHoCprotocol

IFEM Consensus Sonography in Hypotension and Cardiac Arrest

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des clicheacutes suppleacutementaires ou additionnels suivant les

indications cliniques Les prises de vue de base dans les cas

drsquoarrecirct cardiaque recommandeacutees dans le protocole com-

prennent des images sous-xiphoiumldiennes ou parasternales du

cœur qui reacuteduisent au minimum les pauses durant les

compressions thoraciques les clicheacutes suppleacutementaires com-

prennent des images des poumons et de la VCI et les clicheacutes

additionnels comprennent drsquoautres images suivant les indica-

tions cliniques Il est recommandeacute dans les deux types de cas

viseacutes par le protocole drsquoappliquer la meacutethode des laquo 4 F raquo

fluid form function fillingConclusion Est exposeacute ici un consensus international sur

lrsquoutilisation de lrsquoeacutechographie dans les cas drsquohypotension et

dans les cas drsquoarrecirct cardiaque Toutefois son application

exige une validation prospective future

Keywords ultrasound shock hypotension life support

INTRODUCTION

The use of point of care ultrasound (PoCUS) as anadjunct to the practice of emergency medicine is now wellestablished internationally Initially evidence to supportthe use of PoCUS came from the management of blunttrauma patients1 The scope of practice has expanded asemergency physicians have identified further clinicalproblems where PoCUS is able to aid diagnosis and guideprocedures Assessment of patients in cardiac arrest andwith undifferentiated hypotension are core applications ofPoCUS with various protocols in widespread use inemergency medicine23 Previously published protocolsare based upon a logical approach to identifying the likelyetiology and guiding therapy but these protocols arefrequently based solely on expert opinion and not on theactual incidence of disease and tend to follow a didacticrigid approach4-5 Evidence supporting the use of PoCUSin hypotension is limited to diagnostic improvements4-5

The International Federation for Emergency Medicine(IFEM) Ultrasound Special Interest Group (USIG) wastasked with development of a consensus approach to theuse of PoCUS in patients with hypotension and cardiacarrest taking into account previously published recom-mendations as well as the reported incidence of diseaseseen with PoCUS in these clinical scenarios6

PoCUS is an invaluable tool that has potential toclarify essential diagnoses and yield findings that altermanagement plans45 For undifferentiated hypoten-sion it enables a clinician to assess the category of shockand the response to initial management

Previously published algorithms fail to adopt a hier-archical approach to their various components1-3 andmost recommend that every patient receives every viewevery time The aim of this consensus was to develop anapproach that could be adapted to each clinical scenario

For cardiac arrest patients although PoCUS iscommonly taught and performed7 to our knowledge noguidelines have yet addressed practical issues such as

operator safety and minimizing delays in cardio-pulmonary resuscitation (CPR)The objectives of this group were to provide

consensus-based approaches incorporating reporteddisease incidence for the use of sonography in hypo-tension and cardiac arrest (SHoC) The SHoC protocolis presented along with a consensus developed Checklistfor clinicians who wish to safely incorporate PoCUSinto the resuscitation of the arrested patient

METHODOLOGY

The IFEM USIG invited 24 recognized internationalleaders in PoCUS from emergency medicine and criticalcare to form an expert panel to develop the SHoC pro-tocol Baseline disease incidence was derived using thereported interim findings of two multicenter prospectivestudies that examined ultrasound use in undifferentiatedhypotension and in cardiac arrest (see Tables 1 and 2)6

The panel was also provided with a list of recommendedPoCUS views in previously published protocols andguidelines (see Table 3) Using a modified Delphi meth-odology the expert panel was tasked with integrating thedisease incidence their clinical experience and theirknowledge of the medical literature to evaluate what roleeach view should play in the proposed SHoC protocol8

Table 1 International data for incidence of ultrasound

findings in undifferentiated hypotension6

Sonography in hypotension

Finding Frequency

LV dynamic change 43IVC abnormalities 27Pericardial effusion 16Pleural fluid 8Peritoneal fluid 5AAA 2

AA = abdominal aortic aneurysm IV = inferior vena cava L = left ventricular

Atkinson et al

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The panel was asked to assign these views to any of fourdifferent priorities in the hierarchical approach and pro-vide a rationale for their decision (see Table 4) The panelwas also asked to structure the protocol in a manner thatwould be efficient to perform and would be consistentwith current standardized methods for teaching criticalcare PoCUS (see Table 5)

Reaching consensus

Consensus on the SHoC protocols for hypotension andcardiac arrest was reached after three rounds of themodified Delphi process Typically consensus wasdeclared for a given view after that view was assigned toa certain hierarchy with a two-thirds majority at thatlevel or higher (see Appendix 1)

In addition to this process panel members reviewedmodified and approved an operator Checklist to guideclinicians incorporating PoCUS into the assessment andresuscitation of the arrested patient developed by theUltrasound Subcommittee of the Australasian College ofEmergency Medicine (ACEM) using the describedconsensus methods Current recommendations from theInternational Liaison Committee on Resuscitation andits member organisations were provided to the panel910

The final SHoC protocol and operator Checklistreceived panel consensus approval (SHoC-hypotensionreceived 82 and SHoC-cardiac arrest received 83approval of panel members) The IFEM Boardapproved the final recommendations

RECOMMENDATION

1 SHoC-Hypotension

The expert panel reached consensus and recommendsthe following SHoC-hypotension protocol

Core views focus on determining the category of shockwhether cardiogenic or non-cardiogenic and consist of

1 Basic cardiac views (primarily the subxiphoid windowor parasternal long axis window for pericardial fluidcardiac form and ventricular function)

2 Lung views for pleural fluid and B-lines for fillingstatus and

3 IVC views for filling status

Supplementary views should be performed if furtherinformation is required regarding pericardial fluid orcardiac form or function and include the additionalcardiac views (parasternal short axis and apical views)

Table 2 Local data for incidence of ultrasound findings in

cardiac arrest6

Sonography in cardiac arrest

Finding Frequency

Contractility abnormality 45Abnormal valve function 39Pericardial effusion 0

Table 3 PoCUS views assessed by the expert panel for

inclusion in the SHoC protocols

1) Sub-xiphoid or parasternal long axis view2) IVC views3) Additional cardiac views (apical four chamberparasternal

short axis)4) Lung (pleural and pulmonary) views5) Abdomen views for peritoneal fluid6) Aorta views for abdominal aortic aneurysm7) Pelvic views for intrauterine pregnancy8) Lower extremity views for DVT

DVT = deep venous thrombosis IVC = inferior vena cava PoCUS = point of careultrasound SHoC = sonography in hypotension and cardiac arrest

Table 4 Hierarchy levels for scans to be included

1) Core To be performed routinely for all patients2) Supplementary To be performed for all patients where this

would likely add further information without delaying ongoingcritical care

3) Additional To be performed when clinically indicated accordingto the specific clinical circumstances

4) Do Not Include Not appropriate for patients withundifferentiated hypotension or cardiac arrest

Table 5 Teaching structure for key findings

Cardiac views

1) Fluid Is there a significant pericardial effusion2) Form Is the heart small normal or large Is the LV larger than

the RV3) Function Is there vigorous contractility Are the valves

openingIVC and lung views

4) Filling Is the IVC dilated and non-collapsing Is the IVC smalland collapsing Are there multiple B-lines in the lungsbilaterally Is there pleural fluid

IVC = inferior vena cava LV = left ventricular RV = right ventricular

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In many clinical scenarios determining a source ofhypovolemia or cardiovascular strain is essential Toassist with this Additional views including peritonealfluid aorta pelvic for intrauterine pregnancy (IUP)and proximal leg veins for deep venous thrombosis(DVT) should be performed when indicated Impor-tantly although the consensus reached was to includeabdomino-pelvic views for peritoneal fluid as anAdditional (or optional) view this should beconsidered Supplementary (ranked as more important)for women of childbearing age

2 SHoC-Cardiac Arrest

The expert panel reached consensus and recommends thefollowing SHoC-cardiac arrest protocol The agreedprotocol focuses on the timing of PoCUS as well asspecific clinical questions

Core views are limited to cardiac views and must beperformed during the rhythm check pause in chestcompressions without causing prolonged interruptionin chest compressions The preferred view is thesubxiphoid window or the parasternal long axis windowif necessary Either view should be used to look forpericardial fluid as well as examining ventricular form(eg right heart strain) and function (eg asystoleversus organized cardiac activity)Supplementary views include lung views (for absent

lung sliding in pneumothorax and for pleural fluid) andIVC views for fillingAdditional applications that may assist during

cardiac arrest include the use of PoCUS for endo-tracheal tube confirmation scanning proximal leg veinsfor DVT or looking for sources of blood loss (AAAperitoneal or pelvic fluid)These consensus protocols do not specify how find-

ings should direct clinical management They instead

Figure 2 Included views in the SHoC-hypotension protocol

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represent a consensus on the prioritization of scanningfor these critically ill patients based on the likelihood ofdetection of underlying pathology and the perceivedimpact on patient management

DISCUSSION

PoCUS is an essential tool for the evaluation of manypatients in the ED A ldquoone size fits allrdquo investigation israrely appropriate for any critically ill ED patient yet thisis how many of the current PoCUS protocols approachpatients with undifferentiated hypotension (all patientsget all included views all the time) or cardiac arrestExamples of commonly recommended yet rarely positiveviews are those for peritoneal fluid and for aortic aneur-ysm It is likely that as these views were commonly taughtas core emergency ultrasound scans they have beenincluded in hypotension protocols as a result of famil-iarity Our expert panel reached the consensus thatalthough obtaining peritoneal views to assess for

peritoneal fluid or views for AAA are essential in certainpatient categories the diagnostic yield is low and rarelyhelpful as a first-line scan The SHoC protocolsrsquo hier-archical approaches based on the pre-test probability ofdisease are advantageous over current ldquoone size fits allrdquostandardsIn the SHoC-hypotension protocol all patients first

receive a basic cardiac view such as the subxiphoidor parasternal long axis window to look for pericardialfluid the form or size and shape of the cardiacchambers and the function of the ventricles next lungviews for evidence of pneumothorax multiple bilateralB-lines indicating potential pulmonary edema or pleuraleffusions consistent with congestive heart failureand then and an IVC view looking for respiratoryvariation in size Together these views should helpdetermine whether the hypotensive patient is likely to befluid responsive or not a key initial factor in resuscita-tion These views will also exclude clinically obscurepathology such as cardiac tamponade In patients for

Figure 3 SHoC-hypotension protocol summary

IFEM Consensus Sonography in Hypotension and Cardiac Arrest

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whom a diagnosis is not immediately clear and for whomdefinitive management would not be delayed supple-mentary cardiac views such as the parasternal short andapical windows should also be obtained Additionalviews are only recommended when clinically indicated toexclude specific suspected pathology

In the SHoC-cardiac arrest protocol the focus is toobtain a global view of the heart during the hiatus inchest compressions for a brief rhythm check The coresub-xiphoid view or back-up parasternal long axis viewwill enable detection of pericardial fluid as well as afocused assessment for cardiac form and function Thedetection of potentially reversible causes of cardiacarrest is essential during the early phases of themanagement of patients with non-shockable rhythmsDetection of a massively enlarged right ventricle mayindicate an underlying pulmonary embolism whereas

vigorous ventricular contractility may indicate ahypovolemic state Supplementary views include lungand IVC views These views will be achievable duringestablished resuscitation or in the peri-arrest or post-resuscitation phase Bilateral lung sliding confirmsadequate ventilation and excludes tension pneu-mothorax Multiple B-lines or bilateral pleuraleffusions may point to congestive heart failure A smallcollapsing IVC may confirm a hypovolemic state Alarge dilated IVC is a common finding during cardiacarrest Again additional views are only recommendedwhen clinically indicated and must not interruptongoing chest compressions but may assist with pro-cedures such as confirmation of tracheal intubationThe checklist (provided in Appendix 2) may be usedwith the SHoC-cardiac arrest protocol to guidepractitioners in the practical details related to the

Figure 4 Included views in SHoC-cardiac arrest protocol

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performance of PoCUS when resuscitating a patient incardiac arrest

We believe that a hierarchical approach based uponestablished incidence of disease or the estimated like-lihood of disease is consistent with the fact that PoCUSshould be used as a diagnostic tool instead of ascreening tool When a scan is performed to assess foran unexpected etiology (a screening scan) a positivefinding is more likely to be incidental and may distractfrom the underlying diagnosis If the same scan isperformed for an expected etiology (a diagnostic scan) apositive finding is far more likely to be pertinent to theaccurate diagnosis The SHoC protocol is the firstPoCUS approach with an international consensus thatis focused on diagnostic and resuscitative purposesThese recommendations are derived from expert con-sensus in an effort to standardize the approach toPoCUS in critically ill patients Research needs to be

performed to validate this approach and to show itimproves patient outcomes over existing resuscitationprotocols The recommended protocols are depicted inFigures 2-5 and in Appendices 1 and 2

CONCLUSION

We present an international consensus for the use ofsonography in hypotension and cardiac arrest (SHoC)based on prospectively collected disease incidence Theproposed SHoC protocols for hypotension and cardiacarrest and the cardiac arrest checklist are stepwiseclinical-indication based approaches incorporatingCore Supplementary and Additional PoCUS views

Acknowledgements We are grateful to the following indivi-duals for their time and expertise as members of the expert paneland advisory committees Paul Atkinson Justin Bowra David

Figure 5 SHoC-cardiac arrest protocol summary

IFEM Consensus Sonography in Hypotension and Cardiac Arrest

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Lewis Rip Gangahar Mike Lambert Bob Jarman Vickie NobleHein Lamprecht Tim Harris Melanie Stander Christofer MuhrJim Connolly Romolo Gaspari Ross Kessler Chris Raio PaulSierzenski Beatrice Hoffmann Chau Pham Michael Woo PaulOlszynski Ryan Henneberry Oron Frenkel Jordan ChenkinGreg Hall Louise Rang Maxime Valois Chuck Wurster MarkTutschka Rob Arntfield Jason Fischer Mark Tessaro J ScottBomann Adrian Goudie Gaby Blecher Andreacutee Salter MichaelRose Adam Bystrzycki Shailesh Dass Owen Doran Ruth LargeHugo Poncia Alistair Murray Jan Sadewasser Raoul BreitkreutzLarry Melniker Rip Gangahar Toh Hong Chuen Arif AlperCevik and Ang Shiang-Hu

We also wish to thank Ms Carol Reardon Dr Terry Mulliganand Dr Jim Ducharme of IFEM for their advice on themanuscript

REFERENCES

1 Scalea TM Rodriguez A Chiu WC et al Focusedassessment with sonography for trauma (FAST) resultsfrom an international consensus conference J Trauma199946(3)466-72

2 Perera P Mailhot T Riley D et al The RUSH examRapid Ultrasound in SHock in the evaluationof the critically lll Emerg Med Clin North Am 201028(1)29-56

3 Atkinson P McAuley D Kendall R et al Abdominal andCardiac Evaluation with Sonography in Shock (ACES) Anapproach by emergency physicians for the use of ultrasoundin the undifferentiated hypotensive patient Emerg Med J20092687-91

4 Jones AE Tayal VS Sullivan DM et al Randomizedcontrolled trial of immediate versus delayed goal-directedultrasound to identify the cause of nontraumatic hypoten-sion in emergency department patients Crit Care Med200432(8)1703-8

5 Elmer J Noble VE An evidence-based approach forintegrating bedside ultrasound into routine practice in theassessment of undifferentiated shock ICU Director 20101(3)163-74

6 Milne J Atkinson P Lewis D et al Sonography in Hypo-tension and Cardiac Arrest (SHoC) Rates of abnormalfindings in undifferentiated hypotension and during cardiacarrest as a basis for consensus on a hierarchical point of careultrasound protocol Cureus 20168(4)e564 doi107759cureus564

7 Australasian College for Emergency Medicine Policy 61Policy on Credentialing for Echocardiography in Life Sup-port accessed 25072016 Available at httpswwwacemorgaugetattachment2cbfeee3-dd4e-48fe-9e42-f77d2f145893Policy-on-Credentialling-for-Echocardiography-in-Laspx(accessed September 1 2016)

8 Okoli C Pawlowski SD The Delphi method as a researchtool an example design considerations and applicationsInformation amp management 200442(1)15-29

9 Soar J Nolan JP Boumlttiger BW et al European resuscitationcouncil guidelines for resuscitation 2015 section 3 Adultadvanced life support Resuscitation 201595100-47

10 Australian Resuscitation Council Guideline 116 - Equipmentand Techniques in Adult Advanced Life SupportAvailable at httpresusorgauguidelines (accessed July 72016)

11 Gaspari R Weekes A Adhikari S et al Emergency depart-ment point-of-care ultrasound in out-of-hospital and in-EDcardiac arrest Resuscitation 201610933-9 doi 101016jresuscitation201609018

APPENDIX 1 RATES OF EXPERT PREFERENCE FOR PRIORITYOF EACH VIEW

APPENDIX 2 ULTRASOUND IN CARDIAC ARRESTCHECKLIST

Preamble

This is a checklist to guide practitioners in theperformance of point of care ultrasound (PoCUS) whenresuscitating a patient in cardiac arrest It has been devel-oped by the Ultrasound Subcommittee of the AustralasianCollege for Emergency Medicine (ACEM) and theUltrasound Curriculum Working Group of the Interna-tional Federation for Emergency Medicine (IFEM) Itincorporates recommendations from International LiaisonCommittee on Resuscitation (ILCOR) member organisa-tions and the international consensus process on PoCUSin shock and cardiac arrest led by IFEM

Checklist

Please note that the checklist only applies to patients incardiac arrest and also that the Advanced (Cardiac) Life

Priority Selection Rates

View Core Supplementary AdditionalDo notinclude

Sub-xiphoid orparasternal

100 0 0 0

IVC 78 13 9 0Additional cardiac 9 65 26 0Lung 68 32 0 0Peritoneal fluid 0 32 68 0Aorta 13 26 57 4Pelvic views for IUP 0 13 78 9Leg views for DVT 0 9 83 9

Bold percentages indicate views reaching threshold for inclusionIUP = intrauterine pregnancy IVC = inferior vena cava DVT = deep vein thrombosis

Atkinson et al

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Support (ALSACLS) algorithm takes priority at alltimes Please also see the Notes section for a detailedexplanation of the checklist

1 Team briefing

a Is it likely that PoCUS will alter the outcome ofthis case

Yes team leader assigns a team member toperform PoCUS

No continue standard ALSACLS

b Safety briefingc Which side of patient to set up ultrasound

machined Scanning team member is to scan and save

images during rhythm checks

2 Prepare the machine prior to patient arrival (if timepermits)

a Patient details choose ldquotemporary IDrdquo

b Probe sector ideal curved acceptablec Preset cardiac ideal abdominal or ldquoFASTrdquo

acceptabled Initial window (core cardiac) sub-xiphoid ideal

parasternal long-axis acceptablee Depth (and focus if available) set to 25 cm for

adult subcostal far gain turned upf Save video clips or cine-loops rather than still

imagesg Position probe during CPR if possible to set

up your view before break in CPR

3 Perform the scan during breaks in CPR

a Core views (cardiac) fluid form functionb Consider Supplementary views lungs inferior

vena cava (IVC)c Consider Additional views as clinically

indicated

4 Review the images during CPR5 Clinical decisions and interventions based on

PoCUS findings and then reassess6 Cease scanning when team leader decides that

PoCUS is non-contributory or no longer required7 Post-resuscitation

a Amend patient details on the US machine thensave exam

b Documentation in clinical recordc Clean up and debrief

Notes

Team briefing This can occur prior to ALSACLS orat any stage during ALSACLS Although PoCUS mayimprove outcomes in patients with reversible causes forcardiac arrest (CA) not all clinicians are trained in focusedcardiac US and not all cases of CA require PoCUS (egshockable rhythm with return of spontaneous circulation)Safety briefing is crucial the team member performingthe scan will have their hands and the transducer incontact with the patient while the defibrillator is ldquoliverdquo

Preparing the machine Ideally this step should havebeen considered and planned in advance with the idealpre-set cine-loop length retrospective loop functionprogrammed by the local ED team Choose ldquotemporaryIDrdquo or enter patient details after resuscitation is com-pleted Choice of probe transducer is up to the indi-vidual Sector probe is ideal in adults curvilinear probe isacceptable and linear probe (ideally using trapezoidldquovirtual convexrdquo setting) is ideal for infants If focal zoneis available on the machine set this at 20-25 cm It ispreferable to save video clipscine-loops rather than stillimages When preparing to scan test whether themachine is saving prospective or retrospective loops bypressing the ldquosaverdquo button Also consider whether youcan find and can review saved loops with the teamleader

Performing the scan and reviewing images Timingis crucial Obtain and record images during breaks in CPRbut review images during CPR Show the loops to the teamleader and try not to distract the rest of the team

Core views (cardiac)

Fluid in pericardial space suggests pericardial tampo-nade in the appropriate clinical context Other signsare generally sought eg right ventricular (RV)diastolic collapse but details are beyond the scopeof this document

Form a small left ventricle (LV) suggests hypovolemia Agrossly dilated LV suggests chronic cardiac failure If theRV diameter is greater than that of the LV this suggestsright heart strain (eg pulmonary embolus [PE])

IFEM Consensus Sonography in Hypotension and Cardiac Arrest

CJEM JCMU 20160(0) 11

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Function although absence of organised LV activitysuggests a poor outcome it has not been shown to be100 predictive of futility11

Supplementary views (lung IVC) These should besought only if time permits and additional informationrequired

Lungs if clinical suspicion of tension pneumothorax(TPTX) or endotracheal tube (ETT) misplacementscan the anterior surface of each hemithoraxconsider additional lung views if clinical suspicionof other pathology Note that in both TPTX andunventilated lung lung sliding is absent on USDifferentiating requires a combination of clinicalassessment (eg how far down is ETT Is there anyreason for PTX in this patient Is the patient difficultto ventilate) and US features (presence of lung pulseor any comets B-lines will rule out PTX on thatside) It is not recommended to seek the rdquolung pointrdquosign as this only present in smaller PTX and will be

absent in both unventilated lung and TPTX If thereis still doubt either or both finger thoracostomy orETT withdrawal may be considered at the discretionof the team leader

Inferior vena cava (IVC) a large IVC with minimalrespiratory variation is usual in cardiac arrest whereasa small IVC with marked respiratory (ventilatory)variability suggests fluid-responsive patient

Additional views These should be performed whenclinically indicated according to the specific circum-stances of the case

Intraperitoneal fluid (eg clinical suspicion ofruptured ectopic pregnancy)

Abdominal aortic aneurysm (AAA) may be anincidental finding in the arrested patient Once againclinical context is paramount

Proximal deep venous thrombosis (DVT) (if suspicionof PE and inconclusive cardiac views)

Atkinson et al

12 20160(0) CJEM JCMU

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