Holley Unaided CPR - EMS World

Cardiac Arrest Should Unaided CPR be a Thing ofthe Past?JOE HOLLEY, MD; FACEP, FAEMS

State EMS Medical Director for TennesseeMedical Director for Memphis and ShelbyCounty Fire Departments and Tennessee TaskForce One: FEMA Urban Search and RescueteamMedical Unit Leader for FEMA’s IncidentSupport TeamCurrently serves multiple private EMS systemsin West TennesseeJoseph Holley, MDMember of the Eagles ConsortiumMedical Director for Paragon MedicalEducation Group

Course overviewOut of hospital cardiac arrest – the problemThe physiology of CPR – why it is so important to get itright?How can we get even more from our CPR?What can CPR using a cadaveric model teach us?Questions

The problem Approximately 350,000 people in the United Statesexperience out of hospital cardiac arrest (OHCA) eachyearOver one OHCA every two minutes 10% survivewww.sca-aware.org

How do we improve outcomes?National registryEducate and train the publicImprove hospital careQuality improvement programsNational collaborativeEnhance performance of EMS systemsExpand research & promote innovative technologies/ treatmentsFrom: Strategies to Improve Cardiac Arrest Survival: A Time to Act, 2015

Unaided manual CPRUnaided manual CPR is thecornerstone of resuscitationTypically the first option forrescuersHas remained essentially unchangedfor 50 years

The physiology of CPR

The physiology of CPR

The physiology of CPR - full duty cycle

CPR performanceHow well do we actually perform CPR?RateDepthFraction25% of patients did notreceive compressions atthe acceptable rateOver 1/3 of patients didnot receivecompressions ofacceptable depth10% of patients did notreceive CPR withinacceptable chestcompression fractionYannopoulos D, et al. Quality of CPR: An important effect modifier in cardiac arrest clinical outcomes and intervention effectiveness trials. Resuscitation. 2015. 94:106-113.

How can we get more from our CPR?Real time CPR FeedbackIntrathoracic pressure regulationActive compression decompression CPRAutomated CPR

Human Cadaveric Model

CadaversUsed in medical schools - most forgot what theytaught usSome used for ATLS educationOften used by other MDs to study/teach bestpracticesLimited use to date in study of CPR

Our goal Incorporating a cadaveric model into CPR researchbased on the desire to: Establish a common platform Demonstrate the mechanical aspects of CPR Research improvement in technique, equipment andperformance

Why a Perfusing Cadaver Model?Translation EMS research ischallenged by: Applicability of animal models Exception from informed consent Human models to demonstratephysiology Realistic models to assess old andnew device design, physiology andfunctionalityThe TeamMinneapolis St. Paul MinnesotaHennepin Co. Med. Ctr. Keith Lurie, MD Lauren Kline Johanna Moore, MDAllina EMS Transportation Charlie Lick, MDRegions Hospital EMS R. J. Frascone, MDMemphis, Tennessee Joe Holley, MD Jim Logan

MethodologyFresh, non-frozen cadaver; n 12Flushed with Metaflow and KelquestrolPerfused with 15 L saline, leaving 5 L IVFMillar pressure catheters placed in right atria (RA), Ao, LCaAirway pressure monitor placedIntracranial pressure (ICP) bolt placedFoleys placed in bilateral iliacs, then inflatedIntubated and ventilated

Similarities of PCM to Pig ModelJust as in V-fib and cadaver pigs, we observedimproved hemodynamics with high-quality CPRIn these cadavers, physiology was qualitativelysimilar to CPR during V-fibLimitation: could not generate meaning diastolic BPin cadavers

Results: Human PCM (n 12)Hemodynamics qualitatively similar tocadaveric pigs, and pigs in V-fibCan assess carotid angiography with SGAsHeart may be 3 – 4 cm more cranial versuswhere currently compressingMay have a novel new model to study andteach CPR physiology & expeditetranslation of CPR science from animals topatients, and reduce the need for animalstudiesQuestionsRemain How much left toright flow is possiblein fresh humancadavers?Effect (if any) ofsaline having adifferent viscositythan blood, and thefact that cadavericvessels are not aselastic as livingmodels.

Cadaveric modelIntrathoracic (Airway) Pressure mmHGPUSHPULLAortic (Blood) Pressure mmHGPUSHPULLIntracranial Pressure (ICP) mmHGPUSHPULL

Pressure versus perfusionAdequate pressure is necessary for blood flow to occur. highpressure ¹ high perfusionPerfusion

Unaided Manual CPR

Unaided manual CPRICPAorticAirwayCompressions 2.0- 2.5cm

Unaided manual CPRICPAorticAirwayIncomplete chest wall recoil

Unaided manual CPRICPAorticAirwayCompression rate greater than 120/min

Feedback-Aided Manual CPR

Feedback-aided manual CPRNon-compliant CPRHigh-quality CPR

ICPAorticAirwayUnaided manual CPR

Feedback-aided manual CPRICPAorticAirwayUnaided CPRAided CPR

Feedback-aided manual CPR ITDICPAorticAirwayUnaided CPRAided CPRAided CPR ITD

ACD – CPR ITD

ICPAorticAirwayUnaided manual CPR

ACD-CPR ITDICPAorticAirwayUnaided CPRACD-CPR ITD

ACD-CPR no ITDICPAorticAirwayUnaided CPRACD-CPR ITDACD-CPR

Automated CPR

ICPAorticAirwayUnaided manual CPR

Automated CPRICPAorticAirwayUnaided CPRAutomated CPR

Automated CPR with ITDICPAorticAirwayUnaided CPRAutomated CPRAutomated CPR ITD

ReviewCardiac arrest remains a significant problemUnderstanding the physiology of CPR is critical toimproving performance and therefore outcomesTools exist to help take your CPR to the next level

Results: Human PCM (n 12) Hemodynamics qualitatively similar to cadaveric pigs, and pigs in V-fib Can assess carotid angiography with SGAs Heart may be 3 –4 cm more cranial versus