- Email: [email protected]
Reply to Letter: Emerging role of arterial blood gases during cardiopulmonary resuscitation: Another reason for invasive arterial pressure monitoring
G Model
ARTICLE IN PRESS
RESUS-6894; No. of Pages 1
Resuscitation xxx (2016) xxx.e1
Contents lists available at ScienceDirect
Resuscitation journal homepage: www.elsevier.com/locate/resuscitation
Letter to the Editor Reply to Letter: Emerging role of arterial blood gases during cardiopulmonary resuscitation: Another reason for invasive arterial pressure monitoring
mental effects on cardiac output during CPR mediated by effects on cardiac preload and intrathoracic pressure. However, these risks need to be weighed against the obvious deleterious effects of hypercapnic acidosis and hypoxia which seem to be a lot more frequent.
Sir,
Conflict of interest statement
We thank Drs. Kim and Kim for their interest in our article1 and for their supportive comments. We agree that an arterial access is advantageous for directly monitoring arterial blood pressure2 and for obtaining an arterial blood gas sample. We have recently described its feasibility in the prehospital setting3 and arterial lines have been inserted by paramedics in our system for years.4 Moreover, the widespread use of portable ultrasound machines made for bedside and prehospital use will facilitate the insertion of arterial lines for large group of users in the near future. Whether arterial blood gas measurements (as the paCO2 or paO2 ) and related parameters as the AaDCO2 will allow to substantially improve clinical decision making has not been elucidated so far, but we believe there is great potential for that. Intraindividual dynamic changes detected by repetitive measurements over the time course of CPR may be particularly useful for that purpose and future studies should clarify that. The value of etCO2 measurement for confirmation of correct endotracheal tube placement during CPR is undisputed by now. However, in the prehospital setting two major factors regarding its interpretation are usually unknown: lung perfusion, reflected by cardiac output and the actually delivered ventilatory minute volume. While the latter can be measured by appropriate devices or is displayed on commercially available ventilators, a notion of the former can also be derived when invasive blood pressures are measured. Thus we believe the future studies need to take into account the expiratory minute volume as well as invasive circulatory parameters when interpreting etCO2 traces. Moreover, current recommendations advise how to ventilate CPR patients in terms of respiration frequency but how much minute volume is actually delivered during ongoing chest compressions under actual clinical CPR conditions has not been examined so far. The CPR guidelines strongly discourage hyperventilation5 but its definition (paCO2 ?, etCO2 ?, minute volume?) in this context remains unclear. We strongly agree that arterial hypocapnia should be strictly avoided under CPR mainly for its effect on brain circulation, however our data demonstrate that it is not a common event. We also recognize that hyperventilation may have detri-
No conflicts of interest to declare. References 1. Spindelboeck W, Gemes G, Strasser C, et al. Arterial blood gases during and their dynamic changes after cardiopulmonary resuscitation: a prospective clinical study. Resuscitation 2016;106:24–9. 2. Prause G, Archan S, Gemes G, et al. Tight control of effectiveness of cardiac massage with invasive blood pressure monitoring during cardiopulmonary resuscitation. Am J Emerg Med 2010;28:6. 3. Wildner G, Pauker N, Archan S, et al. Arterial line in prehospital emergency settings—a feasibility study in four physician-staffed emergency medical systems. Resuscitation 2011;82:1198–201. 4. Prause G, Oswald S, Himler D, Wildner G, Gemes G. The Medizinercorps Graz: a 120-year-old institution of emergency medicine. Prehosp Emerg Care 2013;17:416–20, http://dx.doi.org/10.3109/10903127.2013.785622. 5. Soar J, Nolan JP, Böttiger BW, et al. European Resuscitation Council Guidelines for Resuscitation 2015: section 3. Adult advanced life support. Resuscitation 2015;95:100–47.
Geza Gemes ∗ Division of General Anaesthesiology, Emergency and Intensive Care Medicine, Department of Anaesthesiology and Intensive Care Medicine, Graz, Austria Walter Spindelboeck Division of Gastroenterology and Hepatology, Department of Internal Medicine, Graz, Austria Gerhard Prause Division of General Anaesthesiology, Emergency and Intensive Care Medicine, Department of Anaesthesiology and Intensive Care Medicine, Graz, Austria ∗ Corresponding
author at: Medical University of Graz, Auenbruggerplatz 29, 8036 Graz, Austria. Fax: +43 316 385 14664. E-mail address: [email protected] (G. Gemes) 11 August 2016
http://dx.doi.org/10.1016/j.resuscitation.2016.08.016 0300-9572/© 2016 Published by Elsevier Ireland Ltd.
Please cite this article in press as: Gemes G, et al. Reply to Letter: Emerging role of arterial blood gases during cardiopulmonary resuscitation: Another reason for invasive arterial pressure monitoring. Resuscitation (2016), http://dx.doi.org/10.1016/j.resuscitation.2016.08.016
ARTICLE IN PRESS
RESUS-6894; No. of Pages 1
Resuscitation xxx (2016) xxx.e1
Contents lists available at ScienceDirect
Resuscitation journal homepage: www.elsevier.com/locate/resuscitation
Letter to the Editor Reply to Letter: Emerging role of arterial blood gases during cardiopulmonary resuscitation: Another reason for invasive arterial pressure monitoring
mental effects on cardiac output during CPR mediated by effects on cardiac preload and intrathoracic pressure. However, these risks need to be weighed against the obvious deleterious effects of hypercapnic acidosis and hypoxia which seem to be a lot more frequent.
Sir,
Conflict of interest statement
We thank Drs. Kim and Kim for their interest in our article1 and for their supportive comments. We agree that an arterial access is advantageous for directly monitoring arterial blood pressure2 and for obtaining an arterial blood gas sample. We have recently described its feasibility in the prehospital setting3 and arterial lines have been inserted by paramedics in our system for years.4 Moreover, the widespread use of portable ultrasound machines made for bedside and prehospital use will facilitate the insertion of arterial lines for large group of users in the near future. Whether arterial blood gas measurements (as the paCO2 or paO2 ) and related parameters as the AaDCO2 will allow to substantially improve clinical decision making has not been elucidated so far, but we believe there is great potential for that. Intraindividual dynamic changes detected by repetitive measurements over the time course of CPR may be particularly useful for that purpose and future studies should clarify that. The value of etCO2 measurement for confirmation of correct endotracheal tube placement during CPR is undisputed by now. However, in the prehospital setting two major factors regarding its interpretation are usually unknown: lung perfusion, reflected by cardiac output and the actually delivered ventilatory minute volume. While the latter can be measured by appropriate devices or is displayed on commercially available ventilators, a notion of the former can also be derived when invasive blood pressures are measured. Thus we believe the future studies need to take into account the expiratory minute volume as well as invasive circulatory parameters when interpreting etCO2 traces. Moreover, current recommendations advise how to ventilate CPR patients in terms of respiration frequency but how much minute volume is actually delivered during ongoing chest compressions under actual clinical CPR conditions has not been examined so far. The CPR guidelines strongly discourage hyperventilation5 but its definition (paCO2 ?, etCO2 ?, minute volume?) in this context remains unclear. We strongly agree that arterial hypocapnia should be strictly avoided under CPR mainly for its effect on brain circulation, however our data demonstrate that it is not a common event. We also recognize that hyperventilation may have detri-
No conflicts of interest to declare. References 1. Spindelboeck W, Gemes G, Strasser C, et al. Arterial blood gases during and their dynamic changes after cardiopulmonary resuscitation: a prospective clinical study. Resuscitation 2016;106:24–9. 2. Prause G, Archan S, Gemes G, et al. Tight control of effectiveness of cardiac massage with invasive blood pressure monitoring during cardiopulmonary resuscitation. Am J Emerg Med 2010;28:6. 3. Wildner G, Pauker N, Archan S, et al. Arterial line in prehospital emergency settings—a feasibility study in four physician-staffed emergency medical systems. Resuscitation 2011;82:1198–201. 4. Prause G, Oswald S, Himler D, Wildner G, Gemes G. The Medizinercorps Graz: a 120-year-old institution of emergency medicine. Prehosp Emerg Care 2013;17:416–20, http://dx.doi.org/10.3109/10903127.2013.785622. 5. Soar J, Nolan JP, Böttiger BW, et al. European Resuscitation Council Guidelines for Resuscitation 2015: section 3. Adult advanced life support. Resuscitation 2015;95:100–47.
Geza Gemes ∗ Division of General Anaesthesiology, Emergency and Intensive Care Medicine, Department of Anaesthesiology and Intensive Care Medicine, Graz, Austria Walter Spindelboeck Division of Gastroenterology and Hepatology, Department of Internal Medicine, Graz, Austria Gerhard Prause Division of General Anaesthesiology, Emergency and Intensive Care Medicine, Department of Anaesthesiology and Intensive Care Medicine, Graz, Austria ∗ Corresponding
author at: Medical University of Graz, Auenbruggerplatz 29, 8036 Graz, Austria. Fax: +43 316 385 14664. E-mail address: [email protected] (G. Gemes) 11 August 2016
http://dx.doi.org/10.1016/j.resuscitation.2016.08.016 0300-9572/© 2016 Published by Elsevier Ireland Ltd.
Please cite this article in press as: Gemes G, et al. Reply to Letter: Emerging role of arterial blood gases during cardiopulmonary resuscitation: Another reason for invasive arterial pressure monitoring. Resuscitation (2016), http://dx.doi.org/10.1016/j.resuscitation.2016.08.016