Head Up Cardiopulmonary Resuscitation: Novel Physiological Discoveries and Latest Clinical Outcomes
Main Article Content
Abstract
Despite decades of research, survival rates following cardiac arrest remain dismal. The recent use of pressure-volume (PV) loop analysis has provided important insights into the underlying physiology of cardiopulmonary resuscitation (CPR). During conventional CPR (C-CPR), ventricular ejection is limited, contributing to poor circulatory effectiveness. In contrast, automated head-up CPR (AHUP-CPR)—which combines active compression-decompression (ACD) CPR, an impedance threshold device (ITD), and controlled head-thorax elevation—generates favorable negative intrathoracic pressure, promoting cerebral venous drainage and increases right heart preload, resulting in enhanced stroke volume, cardiac output, and end-tidal CO₂ (ETCO₂) by improving ventricular–pulmonary–arterial circulation. This article summarizes recent advances related to AHUP-CPR with a focus on novel physiological findings derived from intraventricular conductance catheter recordings during ventricular fibrillation, C-CPR, and AHUP-CPR. The PV loop observations shed new light on the mechanisms through which AHUP-CPR improves circulatory efficiency and neurological outcomes.
Article Details
How to Cite
POURZAND, Pouria; METZGER, Anja; LURIE, Keith.
Head Up Cardiopulmonary Resuscitation: Novel Physiological Discoveries and Latest Clinical Outcomes.
Medical Research Archives, [S.l.], v. 13, n. 8, sep. 2025.
ISSN 2375-1924.
Available at: <https://esmed.org/MRA/mra/article/view/6907>. Date accessed: 05 dec. 2025.
doi: https://doi.org/10.18103/mra.v13i8.6907.
Section
Research Articles
The Medical Research Archives grants authors the right to publish and reproduce the unrevised contribution in whole or in part at any time and in any form for any scholarly non-commercial purpose with the condition that all publications of the contribution include a full citation to the journal as published by the Medical Research Archives.
References
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7. Martin SS, Aday AW, Almarzooq ZI, et al. 2024 Heart Disease and Stroke Statistics: A Report of US and Global Data From the American Heart Association. Circulation. 2024;149(8). doi:10.1161/CIR.0000000000001209
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9. Kouwenhoven WB, Jude JR, Knickerbocker GG. Closed-chest cardiac massage. JAMA. 1960;173:1064-1067. doi:10.1001/jama.1960.03020280004002
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24. Kim T, Shin SD, Song KJ, et al. The effect of resuscitation position on cerebral and coronary perfusion pressure during mechanical cardiopulmonary resuscitation in porcine cardiac arrest model. Resuscitation. 2017;113:101-107. doi:10.1016/j.resuscitation.2017.02.008
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27. Voelckel WG, Lurie KG, Sweeney M, et al. Effects of Active Compression-Decompression Cardiopulmonary Resuscitation with the Inspiratory Threshold Valve in a Young Porcine Model of Cardiac Arrest. Pediatr Res. 2002;51(4):523-527. doi:10.1203/00006450-200204000-00020
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30. Duhem H, Moore JC, Rojas-Salvador C, et al. Improving post-cardiac arrest cerebral perfusion pressure by elevating the head and thorax. Resuscitation. 2021;159:45-53. doi:10.1016/j.resuscitation.2020.12.016
31. Duhem H, Terzi N, Segond N, et al. Effect of automated head-thorax elevation during chest compressions on lung ventilation: a model study. Sci Rep. 2023;13(1):20393. doi:10.1038/s41598-023-47727-z
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39. Georgiou M, Papathanassoglou E, Xanthos T. Systematic review of the mechanisms driving effective blood flow during adult CPR. Resuscitation. 2014;85(11):1586-1593. doi:10.1016/j.resuscitation.2014.08.032
40. Higano ST, Oh JK, Ewy GA, Seward JB. The mechanism of blood flow during closed chest cardiac massage in humans: transesophageal echocardiographic observations. Mayo Clin Proc. 1990;65(11):1432-1440. doi:10.1016/s0025-6196(12)62167-3
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43. Fodden DI, Crosby AC, Channer KS. Doppler measurement of cardiac output during cardiopulmonary resuscitation. J Accid Emerg Med. 1996;13(6):379-382. doi:10.1136/emj.13.6.379
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2. Sasson C, Rogers MAM, Dahl J, Kellermann AL. Predictors of Survival From Out-of-Hospital Cardiac Arrest: A Systematic Review and Meta-Analysis. Circ Cardiovasc Qual Outcomes. 2010;3(1):63-81. doi:10.1161/CIRCOUTCOMES.109.889576
3. Bircher NG, Chan PS, Xu Y, for the American Heart Association’s Get With The Guidelines–Resuscitation Investigators. Delays in Cardiopulmonary Resuscitation, Defibrillation, and Epinephrine Administration All Decrease Survival in In-hospital Cardiac Arrest. Anesthesiology. 2019;130(3):414-422. doi:10.1097/ALN.0000000000002563
4. Lurie KG, Nemergut EC, Yannopoulos D, Sweeney M. The Physiology of Cardiopulmonary Resuscitation. Anesth Analg. 2016;122(3):767-783. doi:10.1213/ANE.0000000000000926
5. Duggal C, Weil MH, Gazmuri RJ, et al. Regional blood flow during closed-chest cardiac resuscitation in rats. J Appl Physiol Bethesda Md 1985. 1993;74(1):147-152. doi:10.1152/jappl.1993.74.1.147
6. Lurie KG, Mulligan KA, McKnite S, Detloff B, Lindstrom P, Lindner KH. Optimizing standard cardiopulmonary resuscitation with an inspiratory impedance threshold valve. Chest. 1998;113(4):1084-1090. doi:10.1378/chest.113.4.1084
7. Martin SS, Aday AW, Almarzooq ZI, et al. 2024 Heart Disease and Stroke Statistics: A Report of US and Global Data From the American Heart Association. Circulation. 2024;149(8). doi:10.1161/CIR.0000000000001209
8. Cooper JA, Cooper JD, Cooper JM. Cardiopulmonary resuscitation: history, current practice, and future direction. Circulation. 2006;114(25):2839-2849. doi:10.1161/CIRCULATIONAHA.106.610907
9. Kouwenhoven WB, Jude JR, Knickerbocker GG. Closed-chest cardiac massage. JAMA. 1960;173:1064-1067. doi:10.1001/jama.1960.03020280004002
10. Voorhees WD, Babbs CF, Tacker WA. Regional blood flow during cardiopulmonary resuscitation in dogs. Crit Care Med. 1980;8(3):134-136. doi:10.1097/00003246-198003000-00008
11. Silver DI, Murphy RJ, Babbs CF, Geddes LA. Cardiac output during CPR: a comparison of two methods. Crit Care Med. 1981;9(5):419-420. doi:10.1097/00003246-198105000-00034
12. Rubertsson S, Grenvik A, Wiklund L. Blood flow and perfusion pressure during open-chest versus closed-chest cardiopulmonary resuscitation in pigs. Crit Care Med. 1995;23(4):715-725. doi:10.1097/00003246-199504000-00021
13. Moore JC. Head-up cardiopulmonary resuscitation. Curr Opin Crit Care. 2023;Publish Ahead of Print. doi:10.1097/MCC.0000000000001037
14. Lurie K, Voelckel W, Plaisance P, et al. Use of an inspiratory impedance threshold valve during cardiopulmonary resuscitation: a progress report. Resuscitation. 2000;44(3):219-230. doi:10.1016/S0300-9572(00)00160-X
15. Lurie KG, Coffeen P, Shultz J, McKnite S, Detloff B, Mulligan K. Improving Active Compression-Decompression Cardiopulmonary Resuscitation With an Inspiratory Impedance Valve. Circulation. 1995;91(6):1629-1632. doi:10.1161/01.CIR.91.6.1629
16. Ryu HH, Moore JC, Yannopoulos D, et al. The Effect of Head Up Cardiopulmonary Resuscitation on Cerebral and Systemic Hemodynamics. Resuscitation. 2016;102:29-34. doi:10.1016/j.resuscitation.2016.01.033
17. Rojas-Salvador C, Moore JC, Salverda B, Lick M, Debaty G, Lurie KG. Effect of controlled sequential elevation timing of the head and thorax during cardiopulmonary resuscitation on cerebral perfusion pressures in a porcine model of cardiac arrest. Resuscitation. 2020;149:162-169. doi:10.1016/j.resuscitation.2019.12.011
18. Moore JC, Segal N, Lick MC, et al. Head and thorax elevation during active compression decompression cardiopulmonary resuscitation with an impedance threshold device improves cerebral perfusion in a swine model of prolonged cardiac arrest. Resuscitation. 2017;121:195-200. doi:10.1016/j.resuscitation.2017.07.033
19. Moore JC, Duval S, Lick C, et al. Faster time to automated elevation of the head and thorax during cardiopulmonary resuscitation increases the probability of return of spontaneous circulation. Resuscitation. 2022;170:63-69. doi:10.1016/j.resuscitation.2021.11.008
20. Pourzand P, Moore J, Metzger A, et al. Hemodynamics, survival and neurological function with early versus delayed automated head-up CPR in a porcine model of prolonged cardiac arrest. Resuscitation. 2024;194:110067. doi:10.1016/j.resuscitation.2023.110067
21. Moore JC, Pepe PE, Scheppke KA, et al. Head and thorax elevation during cardiopulmonary resuscitation using circulatory adjuncts is associated with improved survival. Resuscitation. 2022;179:9-17. doi:10.1016/j.resuscitation.2022.07.039
22. Bachista KM, Moore JC, Labarère J, et al. Survival for Nonshockable Cardiac Arrests Treated With Noninvasive Circulatory Adjuncts and Head/Thorax Elevation*. Crit Care Med. 2024;52(2):170-181. doi:10.1097/CCM.0000000000006055
23. Debaty G, Shin SD, Metzger A, et al. Tilting for perfusion: Head-up position during cardiopulmonary resuscitation improves brain flow in a porcine model of cardiac arrest. Resuscitation. 2015;87:38-43. doi:10.1016/j.resuscitation.2014.11.019
24. Kim T, Shin SD, Song KJ, et al. The effect of resuscitation position on cerebral and coronary perfusion pressure during mechanical cardiopulmonary resuscitation in porcine cardiac arrest model. Resuscitation. 2017;113:101-107. doi:10.1016/j.resuscitation.2017.02.008
25. Moore JC, Salverda B, Rojas-Salvador C, Lick M, Debaty G, G. Lurie K. Controlled sequential elevation of the head and thorax combined with active compression decompression cardiopulmonary resuscitation and an impedance threshold device improves neurological survival in a porcine model of cardiac arrest. Resuscitation. 2021;158:220-227. doi:10.1016/j.resuscitation.2020.09.030
26. Shultz JJ, Coffeen P, Sweeney M, et al. Evaluation of standard and active compression-decompression CPR in an acute human model of ventricular fibrillation. Circulation. 1994;89(2):684-693. doi:10.1161/01.cir.89.2.684
27. Voelckel WG, Lurie KG, Sweeney M, et al. Effects of Active Compression-Decompression Cardiopulmonary Resuscitation with the Inspiratory Threshold Valve in a Young Porcine Model of Cardiac Arrest. Pediatr Res. 2002;51(4):523-527. doi:10.1203/00006450-200204000-00020
28. Debaty G, Moore J, Duhem H, et al. Relationship between hemodynamic parameters and cerebral blood flow during cardiopulmonary resuscitation. Resuscitation. 2020;153:20-27. doi:10.1016/j.resuscitation.2020.05.038
29. Segond N, Terzi N, Duhem H, et al. Mechanical ventilation during cardiopulmonary resuscitation: influence of positive end-expiratory pressure and head-torso elevation. Resuscitation. 2023;185: 109685. doi:10.1016/j.resuscitation.2022.109685
30. Duhem H, Moore JC, Rojas-Salvador C, et al. Improving post-cardiac arrest cerebral perfusion pressure by elevating the head and thorax. Resuscitation. 2021;159:45-53. doi:10.1016/j.resuscitation.2020.12.016
31. Duhem H, Terzi N, Segond N, et al. Effect of automated head-thorax elevation during chest compressions on lung ventilation: a model study. Sci Rep. 2023;13(1):20393. doi:10.1038/s41598-023-47727-z
32. Mayer SA, Chong JY. Critical Care Management of Increased Intracranial Pressure. J Intensive Care Med. 2002;17(2):55-67. doi:10.1177/088506660201700201
33. Sakabe T, Tateishi A, Miyauchi Y, et al. Intracranial pressure following cardiopulmonary resuscitation. Intensive Care Med. 1987;13(4):256-259. doi:10.1007/BF00265114
34. Debaty G, Segond N, Duhem H, et al. Comparison of end tidal CO2 levels between automated head up and conventional cardiopulmonary resuscitation: A pre-post intervention trial. Resuscitation. 2024;204:110406. doi:10.1016/j.resuscitation.2024.110406
35. Pepe PE, Scheppke KA, Antevy PM, et al. Confirming the Clinical Safety and Feasibility of a Bundled Methodology to Improve Cardiopulmonary Resuscitation Involving a Head-Up/Torso-Up Chest Compression Technique: Crit Care Med. 2019;47(3):449-455. doi:10.1097/CCM.0000000000003608
36. Marquez AM, Morgan RW, Ross CE, Berg RA, Sutton RM. Physiology-directed cardiopulmonary resuscitation: advances in precision monitoring during cardiac arrest. Curr Opin Crit Care. 2018;24(3):143-150. doi:10.1097/MCC.0000000000000499
37. Konietzke D, Gervais H, Dick W, Eberle B, Hennes HJ. [Models and methods in animal experiments in resuscitation]. Anaesthesist. 1988;37(3):140-149.
38. Cipani S, Bartolozzi C, Ballo P, Sarti A. Blood flow maintenance by cardiac massage during cardiopulmonary resuscitation: Classical theories, newer hypotheses, and clinical utility of mechanical devices. J Intensive Care Soc. 2019;20(1):2-10. doi:10.1177/1751143718778486
39. Georgiou M, Papathanassoglou E, Xanthos T. Systematic review of the mechanisms driving effective blood flow during adult CPR. Resuscitation. 2014;85(11):1586-1593. doi:10.1016/j.resuscitation.2014.08.032
40. Higano ST, Oh JK, Ewy GA, Seward JB. The mechanism of blood flow during closed chest cardiac massage in humans: transesophageal echocardiographic observations. Mayo Clin Proc. 1990;65(11):1432-1440. doi:10.1016/s0025-6196(12)62167-3
41. Voorhees WD, Bourland JD, Lamp ML, Mullikin JC, Geddes LA. Validation of the saline-dilution method for measuring cardiac output by simultaneous measurement with a perivascular electromagnetic flowprobe. Med Instrum. 1985;19(1):34-37.
42. Grubbs DS, Geddes LA, Voorhees WD3rd null. Right-side cardiac output determined with a newly developed catheter-tip resistivity probe using saline indicator. Jpn Heart J. 1984;25(1):105-111. doi:10.1536/ihj.25.105
43. Fodden DI, Crosby AC, Channer KS. Doppler measurement of cardiac output during cardiopulmonary resuscitation. J Accid Emerg Med. 1996;13(6):379-382. doi:10.1136/emj.13.6.379
44. Bastos MB, Burkhoff D, Maly J, et al. Invasive left ventricle pressure-volume analysis: overview and practical clinical implications. Eur Heart J. 2020;41(12):1286-1297. doi:10.1093/eurheartj/ehz552
45. Brener MI, Masoumi A, Ng VG, et al. Invasive Right Ventricular Pressure-Volume Analysis: Basic Principles, Clinical Applications, and Practical Recommendations. Circ Heart Fail. 2022;15(1):e009101. doi:10.1161/CIRCHEARTFAILURE.121.009101
46. Cornwell WK, Tran T, Cerbin L, et al. New insights into resting and exertional right ventricular performance in the healthy heart through real‐time pressure‐volume analysis. J Physiol. 2020;598(13):2575-2587. doi:10.1113/JP279759
47. Patel N, Abdou H, Edwards J, et al. Measuring Cardiac Output in a Swine Model. J Vis Exp JoVE. 2021;(171). doi:10.3791/62333
48. Pourzand P, Moore J, Suresh M, et al. Active decompression during automated head-up cardiopulmonary resuscitation. Resuscitation. 2024;202:110324. doi:10.1016/j.resuscitation.2024.110324
49. Pourzand P, Moore J, Metzger A, et al. Intraventricular pressure and volume during conventional and automated head-up CPR. Resuscitation. Published online February 2025:110551. doi:10.1016/j.resuscitation.2025.110551
50. Protti I, Van Den Enden A, Van Mieghem NM, Meuwese CL, Meani P. Looking Back, Going Forward: Understanding Cardiac Pathophysiology from Pressure–Volume Loops. Biology. 2024;13(1):55. doi:10.3390/biology13010055
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52. Eason J, Gades NM, Malkin RA. A novel ultrasound technique to estimate right ventricular geometry during fibrillation. Physiol Meas. 2002;23(2):269-278. doi:10.1088/0967-3334/23/2/303
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