- Email: [email protected]
Is short always important?
Accepted Manuscript Is short always important? Shimon Rosenheck, MD, FHRS PII:
S1547-5271(17)31130-X
DOI:
10.1016/j.hrthm.2017.09.033
Reference:
HRTHM 7322
To appear in:
Heart Rhythm
Received Date: 13 September 2017
Please cite this article as: Rosenheck S, Is short always important?, Heart Rhythm (2017), doi: 10.1016/ j.hrthm.2017.09.033. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
Is short always important?
RI PT
Shimon Rosenheck, MD, FHRS
Jerusalem, Israel
TE D
M AN U
No conflict of interest related to this manuscript.
SC
Meir Medical Center, Kefar Sava and Hebrew University Faculty of Medicine,
Correspondence to Shimon Rosenheck MD, Heart Institute, Meir Medical Center, 59 Tchernihovsky Street, Kefar Sava 4428164, Israel, phone: 972-9 7472008, fax: 972-9
AC C
EP
7471476; email: [email protected]
1
ACCEPTED MANUSCRIPT
AED (Automatic External Defibrillator) has become an important tool in rescuing patients after sudden cardiac death. The availability of AED is increasing and every
RI PT
highly populated place or isolated locations are equipped with this valuable device. AED has two main functions: 1. Detection and definition of the shockable
arrhythmia; 2. Delivering of appropriate shock to terminate the malignant
SC
arrhythmia.
The detection and correct definition of the arrhythmia requires clean signal input.
masked by external interferences.
M AN U
This is even more critical if the arrhythmia is fine VF when the delicate signal may be
One of the main reasons for low survival after sudden cardiac death is multiple organ damage due to low perfusion during the cardiac arrest. The only way to prevent this extensive organ damage is adequate chest compression and ventilation initiated as soon as possible even by a lay rescuer or a first responder. These are the first steps
TE D
of cardiovascular resuscitation. Chest compression may mask the input signal of the AED and brief interruptions are required for the correct detection. Obviously, during these interruptions the peripheral circulation diminishes and for this reason the
EP
pause has to be as short as possible. The second reason for compression interruption is ventilation. Beside these two required interruption there is also an unintended
AC C
interruption-the rescuer distraction. The American Heart Association guidelines limits the length of the interruption to <10 seconds. (1,2) However, the length of the pausing and its effect on the outcome is controversial. These recommendations are based on observational and randomized studies. Observational studies suggest an association of the preshock pause length and the success of defibrillation and outcome. An interruption of < 10 seconds resulted in 94% of successful defibrillation when > 30 seconds resulted in only 38% successful shocks. The success decreased gradually and linearly between these two extremes (3). Reducing the pre- and postdefibrillation pauses increased the likelihood of successful defibrillation with the highest success at pre shock pause of <3 seconds. (4). In another observational study 2
ACCEPTED MANUSCRIPT a preshock interruption of < 20 seconds resulted in 35.5% success and >20 seconds only 25.1 % success. There was no difference with bellow or above 10 seconds pauses.(5). However two randomized studies failed to approve any benefit from shortening the interruptions (6,7). In the guideline to keep the preshock and postshock pauses as short as possible is a Class I indication LOE C. For ventilation <10
RI PT
second paused received a Class IIa indication LOE C and chest compression fraction of at least 60% received a Class IIb LOE C. (Level of Evidence C is based on expert opinion without strong support in the literature) (2)
SC
Long pauses may be associated with a lower survival to hospital discharge but there is no strong evidence that less ten 10 second pause contribute to better outcome.
M AN U
(5).
In this issue of the Journal, Fumagalli F at al (8) presents an algorithm called “Advisory during CPR with fast Reconfirmation” (ADC-FR) which offers automated ECG analysis and defibrillator discharge during chest compression with 3 seconds ECG rhythm reconfirmation. They demonstrated a high sensitivity and specificity in
TE D
detection of the arrhythmia and appropriate shock advice. The real value of this protocol is still not obvious. First of all, the value of chest compression interruption for less than 10 seconds is not clear and both lay rescuers and first comers may achieve shorter times than 10 seconds interruption in the chest compression. The
(LOE C).
EP
guidelines recommend less than 10-second pauses, but only at a level of evidence C
AC C
There is also a big difference between pure statistical significance and clinical importance. Statistically we may accept high sensitivity and specificity at the level of 90% or above. However clinically is much more acceptable 100% sensitivity in expense of the specificity. This will result in a higher percent of false positive but no false negative and the meaning is that no patient will be denied a necessary shock but occasionally patients will receive an unnecessary shock. So in the clinical life statistical significance is not immediately translated into clinical success especially in life-saving procedures like cardiopulmonary resuscitation and defibrillation.
3
ACCEPTED MANUSCRIPT Future randomized studies will demonstrate if ≤10 seconds interruption in chest compression has important effect on the clinical outcome. References 1. Berg RA, Hemphill R, Abella BS, Aufderheiden TP, Cave DM, Hazinski MF,
RI PT
Lerner EB, Rea TD, Sayer MR, Swor RA. Adult Life Support; 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and
Emergency Cardiovascular Care. Circulation 2010;122[suppl]:S685-S705
SC
2. Kleinman ME, Brennan EE, Goldberger ZD, Swor RA, Terry M, Bobrow BJ,
Gazmuri RJ, Travers AH, Rea T. Adult Basic Life Support and Cardiopulmonary
M AN U
resuscitation quality; 2015 American Heart association guidelines update for cardiopulmonary resuscitation and emergency cardiovascular care. Circulation 2015;132[suppl 2];S414-S435
3. Edelson DP, Abella BS, Kramer-Johansen J, Wik L, Myklebust H, Barry AM,
TE D
Merchant RM, Vanden Hoek TL, Steen P, Becker LB. Effect of compression depth and pre-shock pauses predict defibrillation failure during cardiac
EP
arrest. Resuscitation 2006;71:137-145
AC C
4. Sell RE, Sarno R, Lawrence B, Castillo EM, Fisher R, Brainard C, Dunford JV, Davis DP. Minimizing the pre-and post-shock pauses increases the likelihood of return of spontaneous circulation (ROSC). Resuscitation 2010;81:822-825
5. Cheske S, Schmicker RH, Christenson J, et al. An independent predictor of survival from out-of-hospital shockable cardiac arrest. Circulation 2011;124:58-66
4
ACCEPTED MANUSCRIPT 6. Beesems SG, Wijmans L, tijssen JGP, Koster RW. Duration of Ventilation during cardiopulmonary resuscitation by lay rescuers and first responders. Circulation 2013;127:1585-1590
RI PT
7. Jost D, Degranger H, Verret C, Hersen O, Fuilla C, Migliani R, Carpentier JP and the DEFI 2005 WG. A randomized controlled trial of the effct of automated external defibrillator cardiopulmonary resuscitation protocol on outcome
SC
from out of –hospital cardiac arrest. Circulation2010;121:1614-1622
M AN U
8. Fumagalli F, Silver AE, Tan Q, Zaidi N, Ristagno G. Cardiac rhythm analysis during ongoing cardiopulmonary resuscitation using the “Analysis During Compressions with Fast Reconfirmation” (ADC-FR) technology. Heart Rhythm
AC C
EP
TE D
2017…
5
S1547-5271(17)31130-X
DOI:
10.1016/j.hrthm.2017.09.033
Reference:
HRTHM 7322
To appear in:
Heart Rhythm
Received Date: 13 September 2017
Please cite this article as: Rosenheck S, Is short always important?, Heart Rhythm (2017), doi: 10.1016/ j.hrthm.2017.09.033. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
Is short always important?
RI PT
Shimon Rosenheck, MD, FHRS
Jerusalem, Israel
TE D
M AN U
No conflict of interest related to this manuscript.
SC
Meir Medical Center, Kefar Sava and Hebrew University Faculty of Medicine,
Correspondence to Shimon Rosenheck MD, Heart Institute, Meir Medical Center, 59 Tchernihovsky Street, Kefar Sava 4428164, Israel, phone: 972-9 7472008, fax: 972-9
AC C
EP
7471476; email: [email protected]
1
ACCEPTED MANUSCRIPT
AED (Automatic External Defibrillator) has become an important tool in rescuing patients after sudden cardiac death. The availability of AED is increasing and every
RI PT
highly populated place or isolated locations are equipped with this valuable device. AED has two main functions: 1. Detection and definition of the shockable
arrhythmia; 2. Delivering of appropriate shock to terminate the malignant
SC
arrhythmia.
The detection and correct definition of the arrhythmia requires clean signal input.
masked by external interferences.
M AN U
This is even more critical if the arrhythmia is fine VF when the delicate signal may be
One of the main reasons for low survival after sudden cardiac death is multiple organ damage due to low perfusion during the cardiac arrest. The only way to prevent this extensive organ damage is adequate chest compression and ventilation initiated as soon as possible even by a lay rescuer or a first responder. These are the first steps
TE D
of cardiovascular resuscitation. Chest compression may mask the input signal of the AED and brief interruptions are required for the correct detection. Obviously, during these interruptions the peripheral circulation diminishes and for this reason the
EP
pause has to be as short as possible. The second reason for compression interruption is ventilation. Beside these two required interruption there is also an unintended
AC C
interruption-the rescuer distraction. The American Heart Association guidelines limits the length of the interruption to <10 seconds. (1,2) However, the length of the pausing and its effect on the outcome is controversial. These recommendations are based on observational and randomized studies. Observational studies suggest an association of the preshock pause length and the success of defibrillation and outcome. An interruption of < 10 seconds resulted in 94% of successful defibrillation when > 30 seconds resulted in only 38% successful shocks. The success decreased gradually and linearly between these two extremes (3). Reducing the pre- and postdefibrillation pauses increased the likelihood of successful defibrillation with the highest success at pre shock pause of <3 seconds. (4). In another observational study 2
ACCEPTED MANUSCRIPT a preshock interruption of < 20 seconds resulted in 35.5% success and >20 seconds only 25.1 % success. There was no difference with bellow or above 10 seconds pauses.(5). However two randomized studies failed to approve any benefit from shortening the interruptions (6,7). In the guideline to keep the preshock and postshock pauses as short as possible is a Class I indication LOE C. For ventilation <10
RI PT
second paused received a Class IIa indication LOE C and chest compression fraction of at least 60% received a Class IIb LOE C. (Level of Evidence C is based on expert opinion without strong support in the literature) (2)
SC
Long pauses may be associated with a lower survival to hospital discharge but there is no strong evidence that less ten 10 second pause contribute to better outcome.
M AN U
(5).
In this issue of the Journal, Fumagalli F at al (8) presents an algorithm called “Advisory during CPR with fast Reconfirmation” (ADC-FR) which offers automated ECG analysis and defibrillator discharge during chest compression with 3 seconds ECG rhythm reconfirmation. They demonstrated a high sensitivity and specificity in
TE D
detection of the arrhythmia and appropriate shock advice. The real value of this protocol is still not obvious. First of all, the value of chest compression interruption for less than 10 seconds is not clear and both lay rescuers and first comers may achieve shorter times than 10 seconds interruption in the chest compression. The
(LOE C).
EP
guidelines recommend less than 10-second pauses, but only at a level of evidence C
AC C
There is also a big difference between pure statistical significance and clinical importance. Statistically we may accept high sensitivity and specificity at the level of 90% or above. However clinically is much more acceptable 100% sensitivity in expense of the specificity. This will result in a higher percent of false positive but no false negative and the meaning is that no patient will be denied a necessary shock but occasionally patients will receive an unnecessary shock. So in the clinical life statistical significance is not immediately translated into clinical success especially in life-saving procedures like cardiopulmonary resuscitation and defibrillation.
3
ACCEPTED MANUSCRIPT Future randomized studies will demonstrate if ≤10 seconds interruption in chest compression has important effect on the clinical outcome. References 1. Berg RA, Hemphill R, Abella BS, Aufderheiden TP, Cave DM, Hazinski MF,
RI PT
Lerner EB, Rea TD, Sayer MR, Swor RA. Adult Life Support; 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and
Emergency Cardiovascular Care. Circulation 2010;122[suppl]:S685-S705
SC
2. Kleinman ME, Brennan EE, Goldberger ZD, Swor RA, Terry M, Bobrow BJ,
Gazmuri RJ, Travers AH, Rea T. Adult Basic Life Support and Cardiopulmonary
M AN U
resuscitation quality; 2015 American Heart association guidelines update for cardiopulmonary resuscitation and emergency cardiovascular care. Circulation 2015;132[suppl 2];S414-S435
3. Edelson DP, Abella BS, Kramer-Johansen J, Wik L, Myklebust H, Barry AM,
TE D
Merchant RM, Vanden Hoek TL, Steen P, Becker LB. Effect of compression depth and pre-shock pauses predict defibrillation failure during cardiac
EP
arrest. Resuscitation 2006;71:137-145
AC C
4. Sell RE, Sarno R, Lawrence B, Castillo EM, Fisher R, Brainard C, Dunford JV, Davis DP. Minimizing the pre-and post-shock pauses increases the likelihood of return of spontaneous circulation (ROSC). Resuscitation 2010;81:822-825
5. Cheske S, Schmicker RH, Christenson J, et al. An independent predictor of survival from out-of-hospital shockable cardiac arrest. Circulation 2011;124:58-66
4
ACCEPTED MANUSCRIPT 6. Beesems SG, Wijmans L, tijssen JGP, Koster RW. Duration of Ventilation during cardiopulmonary resuscitation by lay rescuers and first responders. Circulation 2013;127:1585-1590
RI PT
7. Jost D, Degranger H, Verret C, Hersen O, Fuilla C, Migliani R, Carpentier JP and the DEFI 2005 WG. A randomized controlled trial of the effct of automated external defibrillator cardiopulmonary resuscitation protocol on outcome
SC
from out of –hospital cardiac arrest. Circulation2010;121:1614-1622
M AN U
8. Fumagalli F, Silver AE, Tan Q, Zaidi N, Ristagno G. Cardiac rhythm analysis during ongoing cardiopulmonary resuscitation using the “Analysis During Compressions with Fast Reconfirmation” (ADC-FR) technology. Heart Rhythm
AC C
EP
TE D
2017…
5