aware-awareness during resuscitation- aprospective study 2014

Please citehttp://dx.

ARTICLE IN PRESSG ModelRESUS-6129; No. of Pages 7Resuscitation xxx (2014) xxxxxx

Contents lists available at ScienceDirect

Resuscitation

j ourna l h o me pa g e : www.elsev ier .com/ locate / resusc i ta t ion

Clinical Paper

AWAREAWAreness during REsuscitationA prospective study

Sam Parnia , Ken Spearpoint , Gabriele de Vos , Peter Fenwick , Diana Goldberg ,Jie Yanga, Jiawen Zhua, Katie Bakerd, Hayley Killingbacke, Paula McLeanf,Melanie f g g h h

Michael Russell MKayla HaMark Fara Stony Brook Mb Hammersmitc Monteore Md University Hoe Royal Bournef St Georges Hog Emory Univerh Medical Univi Northamptonj Lister Hospitak Cedar Sinai, Ul Croydon Univm James Paget n Ashford & St o Addenbrookep East Sussex Hq Indiana Univer University of

a r t i c l

Article history:Received 28 JuReceived in reAccepted 7 Sep

Keywords:Cardiac arrestConsciousnessAwarenessNear death exOut of body exPost traumaticImplicit memoExplicit memo

A Spanish Correspon

Brook, NY 117E-mail add

http://dx.doi.o0300-9572/ this article in press as: Parnia S, et al. AWAREAWAreness during REsuscitationA prospective study. Resuscitation (2014),doi.org/10.1016/j.resuscitation.2014.09.004

Wood , A. Maziar Zafari , Neal Dickert , Roland Beisteiner , Fritz Sterz ,Bergerh, Celia Warlowi, Siobhan Bullock i, Salli Lovett j,etcalfe Smith McParak, Sandra Marti-Navarette l, Pam Cushingm, Paul Willsn,rrisd, Jenny Suttono, Anthony Walmsleyp, Charles D. Deakind, Paul Littled,berq, Bruce Greysonr, Elinor R. Schoenfelda

edical Center, State University of New York at Stony Brook, NY, USAh Hospital Imperial College, University of London, UKedical Center, New York, USAspital Southampton, Southampton, UKmouth Hospital, Bournemouth, UKspital, University of London, UKsity School of Medicine & Atlanta Veterans Affairs Medical Center, Atlanta, USAersity of Vienna, Austria

General Hospital, Northampton, UKl, Stevenage, UKSAersity Hospital, UKHospital, UKPeters NHS Trust, UKs Hospital, University of Cambridge, UKospital, East Sussex, UKrsity, Wishard Memorial Hospital, Indianapolis, USA

Virginia, Charlottesville, VA, USA

e i n f o

ne 2014vised form 2 September 2014tember 2014

periencesperiences

stress disorderryry

a b s t r a c t

Background: Cardiac arrest (CA) survivors experience cognitive decits including post-traumatic stressdisorder (PTSD). It is unclear whether these are related to cognitive/mental experiences and awarenessduring CPR. Despite anecdotal reports the broad range of cognitive/mental experiences and awarenessassociated with CPR has not been systematically studied.Methods: The incidence and validity of awareness together with the range, characteristics and themesrelating to memories/cognitive processes during CA was investigated through a 4 year multi-centerobservational study using a three stage quantitative and qualitative interview system. The feasibilityof objectively testing the accuracy of claims of visual and auditory awareness was examined using spe-cic tests. The outcome measures were (1) awareness/memories during CA and (2) objective vericationof claims of awareness using specic tests.Results: Among 2060 CA events, 140 survivors completed stage 1 interviews, while 101 of 140 patientscompleted stage 2 interviews. 46% had memories with 7 major cognitive themes: fear; animals/plants;bright light; violence/persecution; deja-vu; family; recalling events post-CA and 9% had NDEs, while 2%described awareness with explicit recall of seeing and hearing actual events related to their resusci-tation. One had a veriable period of conscious awareness during which time cerebral function was notexpected.

translated version of the summary of this article appears as Appendix in the nal online version at http://dx.doi.org/10.1016/j.resuscitation.2014.09.004.ding author at: Department of Medicine, State University of New York at Stony Brook, Stony Brook Medical Center, T17-040 Health Sciences Center, Stony94-8172, USA.ress: [email protected] (S. Parnia).

rg/10.1016/j.resuscitation.2014.09.0042014 Elsevier Ireland Ltd. All rights reserved.a, b c d a


ARTICLE IN PRESSG ModelRESUS-6129; No. of Pages 72 S. Parnia et al. / Resuscitation xxx (2014) xxxxxx

Conclusions: CA survivors commonly experience a broad range of cognitive themes, with 2% exhibiting fullawareness. This supports other recent studies that have indicated consciousness may be present despiteclinically undetectable consciousness. This together with fearful experiences may contribute to PTSD andother cognitive decits post CA.

2014 Elsevier Ireland Ltd. All rights reserved.

1. Introdu

The obstion is assooutcomes inmemory losome similathe possibilfrom CA.3 Iteristic of areported exthe perceivaround themwith dreamassociationperceptionsing thoughthave also bthat were o

Althougnomenon, omethodologCA resuscitaimprecise y(NDE).3 Whthe overall CA, as wellevents and aied. The priof awareneresuscitatioof establishof visual an

2. Method

In this tially pilot(01/20070UK and Austo participarst group opatients westaff to CA eif they met

CA as dehospital resuscitat

Age > 18 y Survivingand careg

Surviving

When poor physicia

ewers all underwent dedicated training regarding theew methodology by the study chief/principle investigator.ed consent was obtained when patients were deemed med-t to complete an in-person interview prior to discharge. Forts who could not be interviewed during their hospital stay, aone interview protocol was established to consent and inter-hese the stion samp

studo thcomdividospits reqd to ted. till aent ape reere montact, an

the sg lev

set ed aischaews en 3 y of asses, each

CA remensibleinatnd mmit eincluuscit

a lacept

the clahe ceter b

e rese This med thisted t

and tction

ervation that successful cardiac arrest (CA) resuscita-ciated with a number of psychological and cognitivecluding post-traumatic stress disorder, depression and

ss as well as specic mental processes that may sharerities with awareness during anaesthesia,1,2 has raisedity that awareness may also occur during resuscitationn addition to auditory perceptions, which are charac-wareness during anesthesia, CA survivors have alsoperiencing vivid visual perceptions, characterized byed ability to observe and recall actual events occurring.4 Although awareness during anesthesia is associated

like states, the specic mental experience described in with CA is unknown. CA patients have reported visual

together with cognitive and mental activity includ- processes, reasoning and memory formation.3 Patientseen reported to recall specic details relating to eventsccurring during resuscitation.4

h there have been many anecdotal reports of this phe-nly a handful of studies have used rigorous researchy to examine the mental state that is associated withtion.47 These studies have examined the scienticallyet commonly used term of near-death experiencesile NDE have been reported by 10% of CA survivors,3

broader cognitive/mental experiences associated with as awareness, and the association between actual CAuditory/visual recollection of events has not been stud-mary aim of this study was to examine the incidencess and the broad range of mental experiences duringn. The secondary aim was to investigate the feasibilitying a novel methodology to test the accuracy of reportsd auditory perception and awareness during CA.

s

multicenter observational study, methods were ini- tested at 5 hospitals prior to study start-up6/2008) at which point the study team recruited 15 US,trian hospitals (out of an original selected group of 25)te in data collection. Between 07/2008 and 12/2012 thef CA patients were enrolled in the AWARE study. Thesere identied using a local paging system that alertedvents. CA patients were eligible for study participationthe following inclusion criteria:

ned by cessation of heartbeat and respiration (in-or out-of-hospital with on-going cardiopulmonaryion (CPR) on arrival at the emergency department (ED)).ears.

patients deemed t for interview by their physiciansivers.

patients providing informed consent to participation.

interviinterviInformically patientelephview tGiven proporin the

Theprior tethics ting inafter hdoctormentecontacwere steam senvelowho wto be cconsendue todifferinments(outlinpital dintervibetweseverit

To ing CAwheredepartonly via combmals, ato perThese CA resshouldthe perabove,of suchfrom tring af

1 Somillusory.considertively tewith VA this article in press as: Parnia S, et al. AWAREAWAreness during REsdoi.org/10.1016/j.resuscitation.2014.09.004

ssible, interviews were completed by a research nursen while the CA survivor was still an inpatient. The

the images, ththrough a diffthemselves.patients by telephone to minimize losses to follow up.everity of the condition, the study provided for a largeof patients being unable to participate due to ill healthle size calculations.y received ethical approval at each participating sitee start of data collection. Following advice from themittee, a protocol was implemented to avoid contac-uals not interviewed during their hospital stay who diedal discharge. Death registries and letters to the patientsuesting permission to contact their patients were imple-identify patients who either died or should not beIf no objections or concerns were raised and patientslive after discharge, a member of the original clinicaln introductory letter together with a stamped addressedquesting permission to contact patients for the studyissed while in hospital. For these patients who agreedted, a member of the research team, obtained informedd completed data collection via the telephone. Howevereverity of the medical condition (and in particular theels of physical impairment) combined with the require-forth by the ethics committee for contacting patientsbove), the time to telephone interviews following hos-rge was between 3 months and 1 year. All in-hospitalwere carried out prior to discharge. These took placedays and 4 weeks after cardiac arrest depending on thethe patients critical illness.s the accuracy of claims of visual awareness (VA) dur-

hospital installed between 50 and 100 shelves in areassuscitation was deemed likely to occur (e.g. emergencyt, acute medical wards). Each shelf contained one image

from above the shelf (these were different and includedion of nationalistic and religious symbols, people, ani-ajor newspaper headlines). These images were installedvaluation of VA claims described in prior accounts.4

de the perception of being able to observe their ownation from a vantage point above. It was postulated thatrge proportion of patients describe VA combined withion of being able to observe events from a vantage pointshelves could be used to potentially test the validityims (as the images were only visible if looking downiling).1 Considering these perceptions may be occur-rain function has returned following resuscitation, we

archers have proposed such recollections and perceptions are likelyethod was proposed as a tool to test this particular hypothesis. We

s to be important as despite widespread interest no studies had objec-his claim. It was considered that should a large group of patientshe ability to observe events from above consistently fail to identifyuscitationA prospective study. Resuscitation (2014),

is could support the hypothesis that the experiences had occurrederent mechanism (such as illusions) to that perceived by the patients

Please cite REshttp://dx.

ARTICLE IN PRESSG ModelRESUS-6129; No. of Pages 7S. Parnia et al. / Resuscitation xxx (2014) xxxxxx 3

also installed a different image (triangle) on the underside of eachshelf to test the accuracy of VA based on the possibility that patientscould have looked upwards after CA recovery or had their eyes openduring CA.

Using a general andcardiac arrquestions aness and minto the nattions and thwas used toin the NDE present) or 32, a NDE wriences



and withou(category 3compatibleof CA eventscore 22) (cin this grouexperiencedpatients haareas whersummarizeinterviews events. One57 year old the top cortion of looksounds, anquotes fromaccounts anan automatalgorithms,awareness non-acute aVA based onshelf was n

2 After the rrequire at leasond debrillatdebrillation i this article in press as: Parnia S, et al. AWAREAWAreness during REsdoi.org/10.1016/j.resuscitation.2014.09.004

Fig. 1. Summary of study enrollment and o

t recall of CA events (median NDE score = 2) (IQR = 3)). The remaining 9 of 101 patients (9%) had experiences

with NDEs. Seven (7%) had no auditory or visual recalls (median NDE scale score = 10 (IQR = 4), highest NDEategory 4). The detailed NDE account from one patientp is summarized in Table 2. The other two patients (2%)

specic auditory/visual awareness (category 5). Bothd suffered ventricular brillation (VF) in non-acutee shelves had not been placed. Their descriptions ared in Table 2. Both were contacted for further in-depthto verify their experiences against documented CA

was unable to follow up due to ill health. The other, aman described the perception of observing events fromner of the room and continued to experience a sensa-ing down from above. He accurately described people,d activities from his resuscitation (Table 2 provides

this interview). His medical records corroborated hisd specically supported his descriptions and the use ofed external debrillator (AED). Based on current AED

this likely corresponded with up to 3 min of consciousduring CA and CPR.2 As both CA events had occurred inreas without shelves further analysis of the accuracy of

the ability to visualize the images above or below theot possible. Despite the installation of approximately

ecognition of a rst shockable rhythm, the built in AED algorithmst 2 min of CPR before a further rhythm check is followed by a sec-ion attempt if advised. Adding in time for analysis of the rhythm andt is likely the period of CA would have been at least 3 min.

1000 shelvevents actuwhere the of CA event

While Ncognitive rinterview tthe narrativAlthough pof NDEs inthemes asidnarratives finto 7 themviolence or(6) seeing recovery fro

4. Discussi

Our datanitive proceperiods. Altperceived hshould be observed frreports frosome meas

The ndCA is intrigcated conscuscitationA prospective study. Resuscitation (2014),

utcomes.

es across the participating hospitals only 22% of CAally took place in the critical and acute medical wardsshelves had been installed and consequently over 78%s took place in rooms without a shelf.DEs provided a quantiable measure of a patientsecollections in relation to CA, using our CA survivorranscripts as part of stage 2 interviews, we evaluatedes of patients memorys without NDEs (NDE scale < 7).rior studies had by enlarge focused on the occurrence

CA only, however our observation that other cognitivee from NDEs also exist in CA led to an evaluation of theor other specic themes. Narratives were categorizedes: (1) fear; (2) animals and plants; (3) a bright light; (4)

a feeling of being persecuted; (5) deja vu experiences;family; (7) recalling events that likely occurred afterm CA. Narratives are presented in Table 3 by theme.

on

suggest that CA patients may experience a range of cog-sses that relate both to the CA and post-resuscitationhough, the relatively high proportion of patients whoaving memories and awareness was unexpected andconrmed through future research, the fact that theequency of NDE (9%) in our study was consistent withm prior studies (approximately 10%),47 may provideure of internal validity for this observation.ing that conscious awareness may be present duringuing and supports other recent studies that have indi-iousness may be present in patients despite clinically



Table 2Categories 4 and 5 recollections from structured interviews.

Category 4 recollectionsI have come

not (my) ttoward a vwere otheemerged (that ran thwaters. Ththe watersbeautiful swas lookin

Category 5 rRecollectio

(Before the cfeel a real feel the pawas reallythen all ofrememberthe patien(woman) bup there.could truswhat that me, the nuface but I cHe had bluhave any h

The next thito me: Ohsaid thoseknow. . .. I

I know who name, butman [com

Post-script medical teidentied Recollectio

At the beginfelt scaredknow befosaw everydoctor waon my che

undetectabwith the apatients widemonstratstates (PVSing and methe recalledences or sirecalled thwhether pa(and whethrence of PTSto the impaand/or sedathe results osibility thatcurrently u

Althoughresults of ogest it maysome investelectrical acsia typicallyafter cardia

Table 3Major non-NDE cognitive themes recalled by patients following cardiac arrest.

Fearas terried. I was told I was going to die and the quickest way was tothe lasng draming

lt scar

ls andplants

lions

light sun walled

ily ta famil

persecng dras who

out ofd to ged. Th

in co

u expexperig to d

occuriencth back from the other side of life. . .God sent (me) back, it wasime(I) had many things to do. . .(I traveled) through a tunnelery strong light, which didnt dazzle or hurt (my) eyes. . .therer people in the tunnel whom (I) did not recognize. When (I)I) described a very beautiful crystal city. . . there was a riverrough the middle of the city (with) the most crystal clearere were many people, without faces, who were washing in. . .the people were very beautiful. . . there was the mostinging. . .(and I was) moved to tears. (My) next recollectiong up at a doctor doing chest compressions.

ecollectionsn # 1ardiac arrest) I was answering (the nurse), but I could alsohard pressure on my groin. I could feel the pressure, couldntin or anything like that, just real hard pressure, like someone

pushing down on me. And I was still talking to (the nurse) and a sudden, I wasnt. I must have (blanked out). . ..but then I can

vividly an automated voice saying, shock the patient, shockt, and with that, up in (the) corner of the room there was aeckoning me. . .I can remember thinking to myself, I cant get

. .she beckoned me. . . I felt that she knew me, I felt that It her, and I felt she was there for a reason and I didnt knowwas. . .and the next second, I was up there, looking down atrse, and another man who had a bald head. . .I couldnt see hisould see the back of his body. He was quite a chunky fella. . .e scrubs on, and he had a blue hat, but I could tell he didntair, because of where the hat was.ng I remember is waking up on (the) bed. And (the nurse) said

you nodded off. . .you are back with us now. Whether she words, whether that automated voice really happened, I dont

I wsay BeiswimI fe

AnimaAll Saw

BrightTheRec

FamilyFamMy

Being BeiThiwasI haburnmen

Deja v. . .egoin

EventsExpemou this article in press as: Parnia S, et al. AWAREAWAreness during REsdoi.org/10.1016/j.resuscitation.2014.09.004

can remember feeling quite euphoric. . .(the man with the blue had was). . .I (didnt) know his full. . .he was the man that. . .(I saw) the next day. . .I saw thise to visit me] and I knew who I had seen the day before.

Medical record review conrmed the use of the AED, theam present during the cardiac arrest and the role theman played in responding to the cardiac arrest.n # 2ning, I think, I heard the nurse say dial 444 cardiac arrest. I. I was on the ceiling looking down. I saw a nurse that I did notrehand who I saw after the event. I could see my body andthing at once. I saw my blood pressure being taken whilst thes putting something down my throat. I saw a nurse pumpingst. . .I saw blood gases and blood sugar levels being taken.

le consciousness.915 For instance, implicit learningbsence of explicit recall has been demonstrated inth undetectable consciousness,913 while others haveed conscious awareness during persistent vegetative).14,15 As the relative contribution of implicit learn-mory in CA is unknown it remains unclear whether

experiences reect the totality of patients experi-mply the tip of a deeper iceberg of experiences notrough explicit memory. It is intriguing to considertients may have greater conscious activity during CAer this and fearful experiences may impact the occur-D) than is evident through explicit recall, perhaps duect of post-resuscitation global cerebral inammationtives on memory consolidation and recall. However,f this and other studies (outlined above) raise the pos-

additional assessments may be needed to complementsed clinical tests of consciousness and awareness.

the etiology of awareness during CA is unknown, theur study and in particular our veried case of VA sug-

be dissimilar to awareness during anesthesia. Whileigators have hypothesized there may be a brief surge oftivity after cardiac standstill,16 in contrast to anesthe-

there is no measurable brain function within secondsc standstill.1721 This atlined isoelectric brain state

which occusince insufcerebral mHowever ita number may lead tthe presencCA as this tive corticafunction. Thship betweof mental pduring CA bral functioperplexing.typically leaand lucid m

Despite the occurrerst large-swhile attemthat occurreexplicit recaexamine thless our verbeyond thetrical activiperiod of awstate.1721 TCA rather thbe expectedwith cardiaa rhythm chrized usingof body expand opticalt short word I could remembergged through deep water with a big ring and I hateit was horrid.ed

plants, no owers.

and tigers.

as shiningseeing a golden ash of light

lking 10 or so. Not being able to talk to themy (son, daughter, son-in-law and wife) came

uted or experiencing violencegged through deep waterle event seemed full of violence and I am not a violent man, it

character.o through a ceremony and . . . the ceremony was to getere were 4 men with me, whichever lied would die. . .. I saw

fns being buried upright.

riencesenced a sense of De-ja vu and felt like knew what people wereo before they did it after the arrest. This lasted about 3 days

rring after initial recovery from cardiac arrested . . .a tooth coming out when tube was removed from my

rs with CA onset usually continues throughout CPRcient cerebral blood ow (CBF) is achieved22 to meetetabolic requirements during conventional CPR.2325

was estimated our patient maintained awareness forof minutes into CA. While certain deep coma stateso a selective absence of cortical electrical activity ine of deeper brain activity,26 this seems unlikely duringcondition is associated with global rather than selec-l hypoperfusion as evidenced by the loss of brain stemus, within a model that assumes a causative relation-uscitationA prospective study. Resuscitation (2014),

en cortical activity and consciousness the occurrencerocesses and the ability to accurately describe eventsas occurred in our veried case of VA when cere-n is ordinarily absent or at best severely impaired is27 This is particularly the case as reductions in CBFd to delirium followed by coma, rather than an accurateental state.28

many anecdotal reports and recent studies supportingnce of NDEs and possible VA during CA, this was thecale study to investigate the frequency of awareness,pting to correlate patients claims of VA with eventsd during cardiac arrest. While the low incidence (2%) ofll of VA impaired our ability to use images to objectivelye validity of specic claims associated with VA, nonethe-ied case of VA suggests conscious awareness may occur

rst 2030 s after CA (when some residual brain elec-ty may occur)16 while providing a quantiable timeareness after the brain ordinarily reaches an isolectriche case indicates the experience likely occurred duringan after recovery from CA or before CA. No CBF would

since unlike ventricular tachycardia, VF is incompatiblec contractility particularly after CPR has stopped duringeck.29 Although, similar experiences have been catego-

the scientically undened and imprecise term of outeriences (OBEs), and further categorized as autoscopy

illusions,3032 our study suggests that VA and veridical



perception during CA are dissimilar to autoscopy since patients didnot describe seeing their own double.47 Furthermore as halluci-nations refer to experiences that do not correspond with objectivereality, our ndings do not suggest that VA in CA is likely to behallucinatoactual vericategorizatparticularlyneurologicalators involillusions or the reality ootherwise.3

associated ically) throascribe meaculture or s

Our resuexperience still. As mosthe term NDthe experiedeath afterthe mentalwell as its rdata also suthe term Nlack of a unideath.3436

views withiOur stud

were unabltion of haviperception standing thnumber of ories could acuity and time to intefor every pabias and coof visual tarsible from aincidents), twithout sheclaims of VAthat a differprovide an and the pein this studand time tovariation inbe warrantvariables wvariables thcerebral recCA, locationrhythm, use

5. Conclus

CA surviCPR includiness. Whileexperiences

delineate the role of explicit and implicit memory following CAand the impact of this phenomenon on the occurrence of PTSD andother life adjustments among CA survivors.

t of

e of

ial s

uscitcherpony desmanu

l app

s stu priong p.

harin

authew a

aren

m Pauratat nat aned.

wled

acknhe Birook

Vikana Silso

nces

neim ;92:5sens esth 2ia S,

and ;74:2

Lommivors ;358:ia S, Wncideivors.son B. Gen Haninof ne;20:2e R, Grienc

M, Bol PS, Ble Riv this article in press as: Parnia S, et al. AWAREAWAreness duringdoi.org/10.1016/j.resuscitation.2014.09.004

ry or illusory since the recollections corresponded withed events. Our results also highlight limitations with theion of experiences in relation to CA as hallucinatory,33

as the reality of human experience is not determinedlly.34,35 Although alterations in specic neuro modu-ved with every day real experiences can also lead tohallucinations, however this does not prove or disprovef any specic experience whether it be love, NDEs or

4,35 In fact the reality of any experience and the meaningwith it is determined socially (rather than neurolog-ugh a social process whereby humans determine andning to phenomenon and experience within any givenociety (including scientic groups and societies).3435

lts provide further understanding of the broad mentalthat likely accompanies death after circulatory stand-t patients experiences were incompatible with a NDE,E while commonly used may be insufcient to describence that is associated with the biological processes of

circulatory standstill. Future research should focus on state of CA and its impact on the lives of survivors aselationship with cognitive decits including PTSD. Ourggest, the experience of CA may be distinguished fromDE, which has many scientic limitations including aversally accepted physiological denition of being nearThis imprecision may contribute to ongoing conictingn the scientic community regarding the subject.3639

y had a number of limitations including the fact that wee to ascertain whether patients response to the ques-ng memories during CA (in category 1) truly reected aof having memories or possibly difculties with under-e question. An additional limitation was the limitedpatients with explicit recall of CA events whose mem-have been further analyzed. Furthermore owing to theseverity of the critical illness associated with CA, therview for patients was invariably not exactly the sametient, which may have introduced biases (such as recallnfabulation) in the recollections. While pre-placementgets in resuscitation areas aimed at testing VA was fea-

practical viewpoint (there were no reported adversehe observation that 78% of CA events took place in areaslves illustrates the challenge in objectively testing the

in CA using our proposed methodology. It also suggestsent and more rened methodology may be needed toobjective visual target to examine the mechanism of VArceived ability to observe events during CA. Althoughy the potential role of cofounders such as age, gender

interview were evaluated, our results indicated a wide these variables. Consequently a larger study woulded to further explore the relationship between theseith VA. Such a study should also explore the impact ofat may impact the quality of cerebral blood ow andovery such as the duration of CA, quality of CPR during

of CA (in-hospital versus out-of hospital), underlying of hypothermia during CA and after ROSC.

ions

vors experience a broad range of memories followingng fearful and persecutory experiences as well as aware-

explicit recall of VA is rare, it is unclear whether these contribute to later PTSD. Studies are also needed to

Conic

Non

Financ

ResResearstudy sin studof the

Ethica

Thicentersurviviviewed

Data s

All to revi

Transp

I Saest, accand thand thexplain

Ackno

Wefrom tStony Bnauth,GeorgiLaura W

Refere

1. Gho2000

2. KersAna

3. Parntion2007

4. Vansurv2001

5. Parnthe isurv

6. Greyunit

7. Schwysis 2002

8. Langexpe

9. JelicSebeSadduscitationA prospective study. Resuscitation (2014),

interest statement

the authors have any conicts of interest to declare.

upport

ation Council (UK), Nour Foundation, Bial Foundation.s worked independent of the funding bodies and thesor. Furthermore, the study sponsor did not participateign, analysis and interpretation of results or the writingscript.

roval

dy obtained ethics approvals from each participatingr to the start of recruitment and data collection. Eachatient gave informed consent prior to their being inter-

g

ors either had access to all the data or the opportunityll data.

cy declaration

rnia as lead author afrm that the manuscript is an hon-e, and transparent account of the study being reportedo important aspects of the study have been omittedy discrepancies from the study as planned have been

gements

owledge the Biostatistical Consultation and supportostatistical Consulting Core at the School of Medicine,

University as well as the help of Drs Ramkrishna Ram-s Kaura, Markand Patel, Jasper Bondad, Markand Patel,pencer, Jade Tomlin, Rav Kaur Shah, Rebecca Garrett,n, Ismaa Khan, and Jade Tomlin with the study.

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AWAREAWAreness during REsuscitationA prospective study1 Introduction2 Methods3 Results4 Discussion5 ConclusionsConflict of interest statementFinancial supportEthical approvalData sharingTransparency declarationAcknowledgementsReferences

aware-awareness during resuscitation- aprospective study 2014

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