Resuscitation 91 (2015) A11–A12
Contents lists available at ScienceDirect
Resuscitation journal homepage: www.elsevier.com/locate/resuscitation
Editorial
To ventilate or not to ventilate? That is the question – again
Artificial ventilation as a method of resuscitation predates chest compression by many years; centuries, if you subscribe to the biblical story of Elijah resuscitating a child.1 Various methods of lung inflation, including the use of bellows, were advocated until Tossach described mouth-to-mouth ventilation in 1744.2 Manual methods of artificial ventilation then became the vogue until mouth-to-mouth ventilation was reintroduced as a medical technique by Elam in 1954.3 Its combination with chest compression to form cardiopulmonary resuscitation (CPR) is described in the classic paper of Kouwenhoven, Jude and Knickerbocker4 in 1960, and this has been the mainstay of modern resuscitation guidelines since their earliest days.5 The first recommendations on the performance of basic life support from the International Liaison Committee on Resuscitation (ILCOR), published in 1997, made a distinction between respiratory arrest (managed with ventilation alone) and cardiac arrest (requiring CPR).6 By 2010, however, a combination of unconsciousness and absent breathing as the indication for starting chest compression, and withdrawal of the initial rescue breaths, resulted in a sequence of actions which, at least for the lay rescuer, could never include ventilation alone.7 A further reason for the decline in importance of mouth-tomouth ventilation is that it was perceived to be unpleasant for the rescuer and difficult to learn and perform. This triggered the concept of chest compression alone, which was introduced by Berg and his colleagues in 1993.8 Over the years, chest compression alone has become a hot topic for the ILCOR international consensus meetings. The current (2010) European Resuscitation Council and American Heart Association resuscitation guidelines now recommend that trained rescuers should perform CPR, with chest compression alone being reserved for untrained rescuers, those who cannot or refuse to ventilate, and those instructed by an emergency telephone dispatcher.9,10 The question of ventilation alone has now been raised anew in a study by Maeda and colleagues in this issue of Resuscitation.11 The authors’ objective was ‘to determine the effectiveness of ventilations in bystander cardiopulmonary resuscitation’. They studied bystander-attended, out-of-hospital, cardiac arrest cases, recording whether the victims were given no resuscitation, mouth-to-mouth ventilation alone, chest compression alone, or CPR. Overall, the onemonth, neurologically favourable, survival rates were 2.8%, 3.9%, 4.5% and 5.0%, respectively. This progressive benefit of no resuscitation → ventilation alone → chest compression alone → CPR is, surely, not unexpected, and it is hard to see how these findings will
http://dx.doi.org/10.1016/j.resuscitation.2015.03.019 0300-9572/© 2015 Elsevier Ireland Ltd. All rights reserved.
alter current practice, not least because, as shown in the study, only about 1% of lay rescuers choose to give ventilation in preference to chest compression. More interesting, and perhaps more relevant, are the reported outcomes in the study of cardiac arrest in children and from noncardiac aetiology. In each case, ventilation alone produced greater benefit than chest compression alone. In spite of the relatively small differences involved, and the few bystanders who applied ventilation alone, these results do seem to underline the importance of ventilation in paediatric and non-cardiac-aetiology cardiac arrest. In their discussion, the authors use these findings to support the concept of CPR being preferable to chest compression alone for initial management of all cardiac arrest cases. They conclude that ‘Conventional [CPR] is ideal in all subgroups of [out-of-hospital cardiac arrests]’. This is a sweeping statement that should be questioned. Chest compression alone is easier than CPR to teach, perform and remember.12 It eliminates the pauses required for ventilation, and can result in better survival rates, particularly in cardiac arrests of cardiac aetiology when defibrillation is rapidly available.13 A recent meta-analysis of studies of out-of-hospital cardiac arrest found very similar outcomes for chest compression alone and CPR.14 If, as epidemiologists, we are looking for the greater good for the greater number, chest compression alone wins, not least because sudden, cardiac-aetiology collapse is common and carries a relatively good prognosis. If, as clinicians, we are striving for the best management for the individual patient, then the evidence remains in favour of combining ventilation with compression in specific circumstances: children, non-cardiac aetiology, delayed or prolonged resuscitation. We await publication of the European, American and other international guidelines towards the end of 2015, but the publicly available information from ILCOR suggests that there will be no significant change in advice from that of 2010. The ‘gold standard’ will still be CPR, with chest compression alone being reserved for those who cannot, or will not ventilate the patient. Perhaps the real message, however, that comes from Maeda and colleagues is that we should be considering a more patient-tailored approach to the guidelines. An example might be: chest compression alone to be taught to the population at large and reinforced by telephone dispatchers; CPR (with ventilation) to be taught to those with a duty of care (healthcare and equivalent personnel), and offered to those who wish to extend their first aid skills. Chest
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Editorial / Resuscitation 91 (2015) A11–A12
compression alone would then become the default resuscitation technique. For those skilled in CPR, ventilation would be added in specific situations: unwitnessed cardiac arrest; children; drowning; after (say) 10 min of resuscitation. There are clearly variations on this theme, and it would be for those responsible for turning scientific evidence into practical guidelines to consider the alternatives. This will not be easy, particularly if the guidelines are to be kept simple, but there is an imminent, golden opportunity to discuss this before the 2015 guidelines are published. Conflict of interest statement The author has no conflict of interest to declare. References 1. Holy Bible. King James Version. 1 Kings 17;21–22. 2. Tossach WA. Med essays and observations, vol. 5; 1744. p. 605–8. 3. Elam JO, Brown ES, Elder JD. Artificial respiration by the mouth-to-mouth method. A study of the respiratory gas exchange of paralysed patients ventilated by the operators expired air. N Engl J Med 1954;250:749–54. 4. Kouwenhoven WB, Jude JR, Knickerbocker GG. Closed-chest cardiac massage. JAMA 1960;173:1064–7. 5. Statement by the Ad Hoc Committee on Cardiopulmonary Resuscitation of the Division of Medical Sciences, National Academy of Sciences, National Research Council. JAMA 1966;198:372–9. 6. Handley AJ, Becker LB, Allen M, van Drenth A, Kramer EB, Montgomery WH. Single-rescuer adult basic life support: an advisory statement from the basic life support working group of the international liaison committee on resuscitation. Resuscitation 1997;34:101–7.
7. Koster RW, Sayre MR, Botha M, et al. 2010 International consensus on cardiopulmonary resuscitation and emergency cardiovascular care science with treatment recommendations. Part 5: adult basic life support. Resuscitation 2010;81S:e48–70. 8. Berg RA, Kern KB, Sanders AB, Otto CW, Hilwig RW, Ewy GA. Bystander cardiopulmonary resuscitation. Is ventilation necessary? Circulation 1993;88:1907–15. 9. Koster RW, Baubin MA, Bossaert LL, et al. European resuscitation council guidelines for resuscitation 2010 section 2. Adult basic life support and use of automated external defibrillators. Resuscitation 2010;81:1277–92. 10. Berg RA, Hemphill R, Abella BS, et al. 2010 American heart association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care. Part 5: adult basic life support. Circulation 2010;122:S685–705. 11. Maeda T, Kamikura T, Tanaka Y, et al. Impact of bystander-performed ventilation on functional outcomes after cardiac arrest and factors associated with ventilation-only cardiopulmonary resuscitation: a large observational study. Resuscitation 2015;91:122–30. 12. Heidenreich JW, Sanders AB, Higdon TA, Kern KB, Berg RA, Ewy GA. Uninterrupted chest compression CPR is easier to perform and remember than standard CPR. Resuscitation 2004;63:123–30. 13. Bobrow BJ, Spaite DW, Berg RA, et al. Chest compression-only CPR by lay rescuers and survival from out-of-hospital cardiac arrest. JAMA 2010;304:1447–54. 14. Yao L, Wang P, Zhou L, et al. Compression-only cardiopulmonary resuscitation vs standard cardiopulmonary resuscitation: an updated meta-analysis of observational studies. Am J Emerg Med 2014;32:517–23.
Anthony J. Handley Hillcrest Cottage, Bartlow Road, Hadstock, Cambridge CB21 4PF, United Kingdom E-mail address: [email protected] 20 March 2015 23 March 2015
Contents lists available at ScienceDirect
Resuscitation journal homepage: www.elsevier.com/locate/resuscitation
Editorial
To ventilate or not to ventilate? That is the question – again
Artificial ventilation as a method of resuscitation predates chest compression by many years; centuries, if you subscribe to the biblical story of Elijah resuscitating a child.1 Various methods of lung inflation, including the use of bellows, were advocated until Tossach described mouth-to-mouth ventilation in 1744.2 Manual methods of artificial ventilation then became the vogue until mouth-to-mouth ventilation was reintroduced as a medical technique by Elam in 1954.3 Its combination with chest compression to form cardiopulmonary resuscitation (CPR) is described in the classic paper of Kouwenhoven, Jude and Knickerbocker4 in 1960, and this has been the mainstay of modern resuscitation guidelines since their earliest days.5 The first recommendations on the performance of basic life support from the International Liaison Committee on Resuscitation (ILCOR), published in 1997, made a distinction between respiratory arrest (managed with ventilation alone) and cardiac arrest (requiring CPR).6 By 2010, however, a combination of unconsciousness and absent breathing as the indication for starting chest compression, and withdrawal of the initial rescue breaths, resulted in a sequence of actions which, at least for the lay rescuer, could never include ventilation alone.7 A further reason for the decline in importance of mouth-tomouth ventilation is that it was perceived to be unpleasant for the rescuer and difficult to learn and perform. This triggered the concept of chest compression alone, which was introduced by Berg and his colleagues in 1993.8 Over the years, chest compression alone has become a hot topic for the ILCOR international consensus meetings. The current (2010) European Resuscitation Council and American Heart Association resuscitation guidelines now recommend that trained rescuers should perform CPR, with chest compression alone being reserved for untrained rescuers, those who cannot or refuse to ventilate, and those instructed by an emergency telephone dispatcher.9,10 The question of ventilation alone has now been raised anew in a study by Maeda and colleagues in this issue of Resuscitation.11 The authors’ objective was ‘to determine the effectiveness of ventilations in bystander cardiopulmonary resuscitation’. They studied bystander-attended, out-of-hospital, cardiac arrest cases, recording whether the victims were given no resuscitation, mouth-to-mouth ventilation alone, chest compression alone, or CPR. Overall, the onemonth, neurologically favourable, survival rates were 2.8%, 3.9%, 4.5% and 5.0%, respectively. This progressive benefit of no resuscitation → ventilation alone → chest compression alone → CPR is, surely, not unexpected, and it is hard to see how these findings will
http://dx.doi.org/10.1016/j.resuscitation.2015.03.019 0300-9572/© 2015 Elsevier Ireland Ltd. All rights reserved.
alter current practice, not least because, as shown in the study, only about 1% of lay rescuers choose to give ventilation in preference to chest compression. More interesting, and perhaps more relevant, are the reported outcomes in the study of cardiac arrest in children and from noncardiac aetiology. In each case, ventilation alone produced greater benefit than chest compression alone. In spite of the relatively small differences involved, and the few bystanders who applied ventilation alone, these results do seem to underline the importance of ventilation in paediatric and non-cardiac-aetiology cardiac arrest. In their discussion, the authors use these findings to support the concept of CPR being preferable to chest compression alone for initial management of all cardiac arrest cases. They conclude that ‘Conventional [CPR] is ideal in all subgroups of [out-of-hospital cardiac arrests]’. This is a sweeping statement that should be questioned. Chest compression alone is easier than CPR to teach, perform and remember.12 It eliminates the pauses required for ventilation, and can result in better survival rates, particularly in cardiac arrests of cardiac aetiology when defibrillation is rapidly available.13 A recent meta-analysis of studies of out-of-hospital cardiac arrest found very similar outcomes for chest compression alone and CPR.14 If, as epidemiologists, we are looking for the greater good for the greater number, chest compression alone wins, not least because sudden, cardiac-aetiology collapse is common and carries a relatively good prognosis. If, as clinicians, we are striving for the best management for the individual patient, then the evidence remains in favour of combining ventilation with compression in specific circumstances: children, non-cardiac aetiology, delayed or prolonged resuscitation. We await publication of the European, American and other international guidelines towards the end of 2015, but the publicly available information from ILCOR suggests that there will be no significant change in advice from that of 2010. The ‘gold standard’ will still be CPR, with chest compression alone being reserved for those who cannot, or will not ventilate the patient. Perhaps the real message, however, that comes from Maeda and colleagues is that we should be considering a more patient-tailored approach to the guidelines. An example might be: chest compression alone to be taught to the population at large and reinforced by telephone dispatchers; CPR (with ventilation) to be taught to those with a duty of care (healthcare and equivalent personnel), and offered to those who wish to extend their first aid skills. Chest
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Editorial / Resuscitation 91 (2015) A11–A12
compression alone would then become the default resuscitation technique. For those skilled in CPR, ventilation would be added in specific situations: unwitnessed cardiac arrest; children; drowning; after (say) 10 min of resuscitation. There are clearly variations on this theme, and it would be for those responsible for turning scientific evidence into practical guidelines to consider the alternatives. This will not be easy, particularly if the guidelines are to be kept simple, but there is an imminent, golden opportunity to discuss this before the 2015 guidelines are published. Conflict of interest statement The author has no conflict of interest to declare. References 1. Holy Bible. King James Version. 1 Kings 17;21–22. 2. Tossach WA. Med essays and observations, vol. 5; 1744. p. 605–8. 3. Elam JO, Brown ES, Elder JD. Artificial respiration by the mouth-to-mouth method. A study of the respiratory gas exchange of paralysed patients ventilated by the operators expired air. N Engl J Med 1954;250:749–54. 4. Kouwenhoven WB, Jude JR, Knickerbocker GG. Closed-chest cardiac massage. JAMA 1960;173:1064–7. 5. Statement by the Ad Hoc Committee on Cardiopulmonary Resuscitation of the Division of Medical Sciences, National Academy of Sciences, National Research Council. JAMA 1966;198:372–9. 6. Handley AJ, Becker LB, Allen M, van Drenth A, Kramer EB, Montgomery WH. Single-rescuer adult basic life support: an advisory statement from the basic life support working group of the international liaison committee on resuscitation. Resuscitation 1997;34:101–7.
7. Koster RW, Sayre MR, Botha M, et al. 2010 International consensus on cardiopulmonary resuscitation and emergency cardiovascular care science with treatment recommendations. Part 5: adult basic life support. Resuscitation 2010;81S:e48–70. 8. Berg RA, Kern KB, Sanders AB, Otto CW, Hilwig RW, Ewy GA. Bystander cardiopulmonary resuscitation. Is ventilation necessary? Circulation 1993;88:1907–15. 9. Koster RW, Baubin MA, Bossaert LL, et al. European resuscitation council guidelines for resuscitation 2010 section 2. Adult basic life support and use of automated external defibrillators. Resuscitation 2010;81:1277–92. 10. Berg RA, Hemphill R, Abella BS, et al. 2010 American heart association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care. Part 5: adult basic life support. Circulation 2010;122:S685–705. 11. Maeda T, Kamikura T, Tanaka Y, et al. Impact of bystander-performed ventilation on functional outcomes after cardiac arrest and factors associated with ventilation-only cardiopulmonary resuscitation: a large observational study. Resuscitation 2015;91:122–30. 12. Heidenreich JW, Sanders AB, Higdon TA, Kern KB, Berg RA, Ewy GA. Uninterrupted chest compression CPR is easier to perform and remember than standard CPR. Resuscitation 2004;63:123–30. 13. Bobrow BJ, Spaite DW, Berg RA, et al. Chest compression-only CPR by lay rescuers and survival from out-of-hospital cardiac arrest. JAMA 2010;304:1447–54. 14. Yao L, Wang P, Zhou L, et al. Compression-only cardiopulmonary resuscitation vs standard cardiopulmonary resuscitation: an updated meta-analysis of observational studies. Am J Emerg Med 2014;32:517–23.
Anthony J. Handley Hillcrest Cottage, Bartlow Road, Hadstock, Cambridge CB21 4PF, United Kingdom E-mail address: [email protected] 20 March 2015 23 March 2015
