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Yoo C, Kang S, Choi SW. Pneumatic driven pulsatile ECMO in vitro evaluation with oxygen tanks. Biomed Eng Lett 2023; 13:681-688. [PMID: 37872990 PMCID: PMC10590354 DOI: 10.1007/s13534-023-00295-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 05/18/2023] [Accepted: 05/25/2023] [Indexed: 10/25/2023] Open
Abstract
Extracorporeal membrane oxygenation device is a procedure in which mechanical systems circulate blood and supply oxygen to patients with impaired cardiopulmonary function. Current venoarterial systems are associated with low patient survival rates and new treatments are needed to avoid left ventricular dilation, which is a major cause of death. In this study, a new mobile pulsatile ECMO with a pump structure that supplies pulsatile flow by using an oxygen tank as a power source is proposed. In vitro experiments conducted under mock circulation system as like patient conditions demonstrated that 2.8 L oxygen can sustain the outflow of 1 L/min of pulsatile blood flow for 53 min, while a 4.6 L tank was able to sustain the same flow for 85 min. The energy equivalent pressure evaluation index of the pulsatile blood pump shows that the mobile pulsatile ECMO could supply sufficient pulsatile blood flow compared to the existing pulsatile ECMO. Through in vitro experiments performed under mock circulation conditions, this new system was proven to supply sufficient oxygen and pulsatile blood flow using the pressure of an oxygen tank even while transporting a patient.
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Affiliation(s)
- Changyoung Yoo
- Interdisciplinary Program in Biohealth-Machinery Convergence Engineering, Kangwon National University, Chuncheon-si, 24341 Republic of Korea
| | - Seongmin Kang
- Program of Mechanical and Biomedical Engineering, College of Engineering, Chuncheon-si, 24341 Republic of Korea
| | - Seong-Wook Choi
- Interdisciplinary Program in Biohealth-Machinery Convergence Engineering, Kangwon National University, Chuncheon-si, 24341 Republic of Korea
- Program of Mechanical and Biomedical Engineering, College of Engineering, Chuncheon-si, 24341 Republic of Korea
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Kanagarajan D, Heinsar S, Gandini L, Suen JY, Dau VT, Pauls J, Fraser JF. Preclinical Studies on Pulsatile Veno-Arterial Extracorporeal Membrane Oxygenation: A Systematic Review. ASAIO J 2023; 69:e167-e180. [PMID: 36976324 DOI: 10.1097/mat.0000000000001922] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023] Open
Abstract
Refractory cardiogenic shock is increasingly being treated with veno-arterial extracorporeal membrane oxygenation (V-A ECMO), without definitive proof of improved clinical outcomes. Recently, pulsatile V-A ECMO has been developed to address some of the shortcomings of contemporary continuous-flow devices. To describe current pulsatile V-A ECMO studies, we conducted a systematic review of all preclinical studies in this area. We adhered to PRISMA and Cochrane guidelines for conducting systematic reviews. The literature search was performed using Science Direct, Web of Science, Scopus, and PubMed databases. All preclinical experimental studies investigating pulsatile V-A ECMO and published before July 26, 2022 were included. We extracted data relating to the 1) ECMO circuits, 2) pulsatile blood flow conditions, 3) key study outcomes, and 4) other relevant experimental conditions. Forty-five manuscripts of pulsatile V-A ECMO were included in this review detailing 26 in vitro , two in silico , and 17 in vivo experiments. Hemodynamic energy production was the most investigated outcome (69%). A total of 53% of studies used a diagonal pump to achieve pulsatile flow. Most literature on pulsatile V-A ECMO focuses on hemodynamic energy production, whereas its potential clinical effects such as favorable heart and brain function, end-organ microcirculation, and decreased inflammation remain inconclusive and limited.
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Affiliation(s)
- Dhayananth Kanagarajan
- From the Critical Care Research Group, The Prince Charles Hospital, Brisbane, Queensland, Australia
- Innovative Cardiovascular Engineering and Technology Laboratory, Critical Care Research Group, The Prince Charles Hospital, Brisbane, Queensland, Australia
- School of Engineering and Built Environment, Griffith University, Gold Coast, Queensland, Australia
| | - Silver Heinsar
- From the Critical Care Research Group, The Prince Charles Hospital, Brisbane, Queensland, Australia
- Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia
- Department of Intensive Care, North Estonia Medical Centre, Tallinn, Estonia
| | - Lucia Gandini
- Innovative Cardiovascular Engineering and Technology Laboratory, Critical Care Research Group, The Prince Charles Hospital, Brisbane, Queensland, Australia
| | - Jacky Y Suen
- Innovative Cardiovascular Engineering and Technology Laboratory, Critical Care Research Group, The Prince Charles Hospital, Brisbane, Queensland, Australia
| | - Van Thanh Dau
- Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia
| | - Jo Pauls
- From the Critical Care Research Group, The Prince Charles Hospital, Brisbane, Queensland, Australia
- Innovative Cardiovascular Engineering and Technology Laboratory, Critical Care Research Group, The Prince Charles Hospital, Brisbane, Queensland, Australia
- School of Engineering and Built Environment, Griffith University, Gold Coast, Queensland, Australia
| | - John F Fraser
- From the Critical Care Research Group, The Prince Charles Hospital, Brisbane, Queensland, Australia
- Innovative Cardiovascular Engineering and Technology Laboratory, Critical Care Research Group, The Prince Charles Hospital, Brisbane, Queensland, Australia
- School of Engineering and Built Environment, Griffith University, Gold Coast, Queensland, Australia
- Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia
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Lim J, Won JY, Ahn CB, Kim J, Kim HJ, Jung JS. Comparison of Hemodynamic Energy between Expanded Polytetrafluoroethylene and Dacron Artificial Vessels. J Chest Surg 2021; 54:81-87. [PMID: 33767024 PMCID: PMC8038878 DOI: 10.5090/jcs.20.134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 11/20/2020] [Accepted: 11/23/2020] [Indexed: 11/16/2022] Open
Abstract
Background Artificial grafts such as polyethylene terephthalate (Dacron) and expanded polytetrafluoroethylene (ePTFE) are used for various cardiovascular surgical procedures. The compliance properties of prosthetic grafts could affect hemodynamic energy, which can be measured using the energy-equivalent pressure (EEP) and surplus hemodynamic energy (SHE). We investigated changes in the hemodynamic energy of prosthetic grafts. Methods In a simulation test, the changes in EEP for these grafts were estimated using COMSOL MULTIPHYSICS. The Young modulus, Poisson ratio, and density were used to analyze the grafts’ material properties, and pre- and post-graft EEP values were obtained by computing the product of the pressure and velocity. In an in vivo study, Dacron and ePTFE grafts were anastomosed in an end-to-side fashion on the descending thoracic aorta of swine. The pulsatile pump flow was fixed at 2 L/min. Real-time flow and pressure were measured at the distal part of each graft, while clamping the other graft and the descending thoracic aorta. EEP and SHE were calculated and compared. Results In the simulation test, the mean arterial pressure decreased by 39% for all simulations. EEP decreased by 42% for both grafts, and by around 55% for the native blood vessels after grafting. The in vivo test showed no significant difference between both grafts in terms of EEP and SHE. Conclusion The post-graft hemodynamic energy was not different between the Dacron and ePTFE grafts. Artificial grafts are less compliant than native blood vessels; however, they can deliver pulsatile blood flow and hemodynamic energy without any significant energy loss.
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Affiliation(s)
- Jaekwan Lim
- Biomedical Research Center, Korea Testing Laboratory, Jinju, Korea
| | - Jong Yun Won
- Department of Thoracic and Cardiovascular Surgery, Korea University College of Medicine, Seoul, Korea
| | - Chi Bum Ahn
- Biomedical Engineering Research Center, Asan Medical Center, Seoul, Korea
| | - Jieon Kim
- Department of Thoracic and Cardiovascular Surgery, Korea University College of Medicine, Seoul, Korea.,Korea Artificial Organ Center, Korea University, Seoul, Korea
| | - Hee Jung Kim
- Department of Thoracic and Cardiovascular Surgery, Korea University College of Medicine, Seoul, Korea.,Korea Artificial Organ Center, Korea University, Seoul, Korea
| | - Jae Seung Jung
- Department of Thoracic and Cardiovascular Surgery, Korea University College of Medicine, Seoul, Korea.,Korea Artificial Organ Center, Korea University, Seoul, Korea
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Wang S, Spencer SB, Kunselman AR, Ündar A. Novel ECG-Synchronized Pulsatile ECLS System With Various Heart Rates and Cardiac Arrhythmias: An In Vitro Study. Artif Organs 2017; 41:55-65. [DOI: 10.1111/aor.12904] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 09/30/2016] [Accepted: 11/10/2016] [Indexed: 11/26/2022]
Affiliation(s)
- Shigang Wang
- Department of Pediatrics, Public Health and Sciences; Penn State Hershey Pediatric Cardiovascular Research Center
| | - Shannon B. Spencer
- Department of Pediatrics, Public Health and Sciences; Penn State Hershey Pediatric Cardiovascular Research Center
| | | | - Akif Ündar
- Department of Pediatrics, Public Health and Sciences; Penn State Hershey Pediatric Cardiovascular Research Center
- Surgery and Bioengineering, Penn State Hershey College of Medicine, Penn State Milton S. Hershey Medical Center; Penn State Hershey Children's Hospital; Hershey PA USA
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Change in myocardial oxygen consumption employing continuous-flow LVAD with cardiac beat synchronizing system, in acute ischemic heart failure models. J Artif Organs 2013; 16:119-28. [DOI: 10.1007/s10047-012-0682-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Accepted: 12/13/2012] [Indexed: 11/26/2022]
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Bělohlávek J, Mlček M, Huptych M, Svoboda T, Havránek Š, Ošt'ádal P, Bouček T, Kovárník T, Mlejnský F, Mrázek V, Bělohlávek M, Aschermann M, Linhart A, Kittnar O. Coronary versus carotid blood flow and coronary perfusion pressure in a pig model of prolonged cardiac arrest treated by different modes of venoarterial ECMO and intraaortic balloon counterpulsation. Crit Care 2012; 16:R50. [PMID: 22424292 PMCID: PMC3964801 DOI: 10.1186/cc11254] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Revised: 02/24/2012] [Accepted: 03/16/2012] [Indexed: 11/25/2022] Open
Abstract
INTRODUCTION Extracorporeal membrane oxygenation (ECMO) is increasingly used in cardiac arrest (CA). Adequacy of carotid and coronary blood flows (CaBF, CoBF) and coronary perfusion pressure (CoPP) in ECMO treated CA is not well established. This study compares femoro-femoral (FF) to femoro-subclavian (FS) ECMO and intraaortic balloon counterpulsation (IABP) contribution based on CaBF, CoBF, CoPP, myocardial and brain oxygenation in experimental CA managed by ECMO. METHODS In 11 female pigs (50.3 ± 3.4 kg), CA was randomly treated by FF versus FS ECMO ± IABP. Animals under general anesthesia had undergone 15 minutes of ventricular fibrillation (VF) with ECMO flow of 5 to 10 mL/kg/min simulating low-flow CA followed by continued VF with ECMO flow of 100 mL/kg/min. CaBF and CoBF were measured by a Doppler flow wire, cerebral and peripheral oxygenation by near infrared spectroscopy. CoPP, myocardial oxygen metabolism and resuscitability were determined. RESULTS CaBF reached values > 80% of baseline in all regimens. CoBF > 80% was reached only by the FF ECMO, 90.0% (66.1, 98.6). Addition of IABP to FF ECMO decreased CoBF to 60.7% (55.1, 86.2) of baseline, P = 0.004. FS ECMO produced 70.0% (49.1, 113.2) of baseline CoBF, significantly lower than FF, P = 0.039. Addition of IABP to FS did not change the CoBF; however, it provided significantly higher flow, 76.7% (71.9, 111.2) of baseline, compared to FF + IABP, P = 0.026. Both brain and peripheral regional oxygen saturations decreased after induction of CA to 23% (15.0, 32.3) and 34% (23.5, 34.0), respectively, and normalized after ECMO institution. For brain saturations, all regimens reached values exceeding 80% of baseline, none of the comparisons between respective treatment approaches differed significantly. After a decline to 15 mmHg (9.5, 20.8) during CA, CoPP gradually rose with time to 68 mmHg (43.3, 84.0), P = 0 .003, with best recovery on FF ECMO. Resuscitability of the animals was high, both 5 and 60 minutes return of spontaneous circulation occured in eight animals (73%). CONCLUSIONS In a pig model of CA, both FF and FS ECMO assure adequate brain perfusion and oxygenation. FF ECMO offers better CoBF than FS ECMO. Addition of IABP to FF ECMO worsens CoBF. FF ECMO, more than FS ECMO, increases CoPP over time.
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Affiliation(s)
- Jan Bělohlávek
- 2nd Department of Medicine - Department of Cardiovascular Medicine, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, U Nemocnice 2, Prague 2, 128 00, Czech Republic
| | - Mikuláš Mlček
- Department of Physiology, 1st Faculty of Medicine, Charles University in Prague, Albertov 5, Prague 2, 128 00, Czech Republic
| | - Michal Huptych
- BioDat Research Group, Department of Cybernetics, Faculty of Electrical Engineering, Czech Technical University in Prague, Karlovo namesti 13, Prague 2, 121 35, Czech Republic
| | - Tomáš Svoboda
- Department of Physiology, 1st Faculty of Medicine, Charles University in Prague, Albertov 5, Prague 2, 128 00, Czech Republic
| | - Štěpán Havránek
- 2nd Department of Medicine - Department of Cardiovascular Medicine, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, U Nemocnice 2, Prague 2, 128 00, Czech Republic
| | - Petr Ošt'ádal
- Department of Cardiology, Na Homolce Hospital, Roentgenova 2/37, Prague 5, 150 30, Czech Republic
| | - Tomáš Bouček
- 2nd Department of Medicine - Department of Cardiovascular Medicine, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, U Nemocnice 2, Prague 2, 128 00, Czech Republic
| | - Tomáš Kovárník
- 2nd Department of Medicine - Department of Cardiovascular Medicine, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, U Nemocnice 2, Prague 2, 128 00, Czech Republic
| | - František Mlejnský
- 2nd Department of Surgery, Cardiovascular Surgery, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, U Nemocnice 2, Prague 2, 128 00, Czech Republic
| | - Vratislav Mrázek
- 2nd Department of Medicine - Department of Cardiovascular Medicine, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, U Nemocnice 2, Prague 2, 128 00, Czech Republic
| | - Marek Bělohlávek
- Translational Ultrasound Research Laboratory, Division of Cardiovascular Diseases, Mayo Clinic Arizona, Scottsdale, AZ, USA
| | - Michael Aschermann
- 2nd Department of Medicine - Department of Cardiovascular Medicine, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, U Nemocnice 2, Prague 2, 128 00, Czech Republic
| | - Aleš Linhart
- 2nd Department of Medicine - Department of Cardiovascular Medicine, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, U Nemocnice 2, Prague 2, 128 00, Czech Republic
| | - Otomar Kittnar
- Department of Physiology, 1st Faculty of Medicine, Charles University in Prague, Albertov 5, Prague 2, 128 00, Czech Republic
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Allen BS, Ko Y, Buckberg GD, Tan Z. Studies of isolated global brain ischaemia: III. Influence of pulsatile flow during cerebral perfusion and its link to consistent full neurological recovery with controlled reperfusion following 30 min of global brain ischaemia. Eur J Cardiothorac Surg 2012; 41:1155-63. [PMID: 22436247 DOI: 10.1093/ejcts/ezr318] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
OBJECTIVE Brain damage is universal in the rare survivor of unwitnessed cardiac arrest. Non-pulsatile-controlled cerebral reperfusion offsets this damage, but may simultaneously cause brain oedema when delivered at the required the high mean perfusion pressure. This study analyses pulsatile perfusion first in control pigs and then using controlled reperfusion after prolonged normothermic brain ischaemia (simulating unwitnessed arrest) to determine if it might provide a better method of delivery for brain reperfusion. METHODS Initial baseline studies during isolated brain perfusion in 12 pigs (six non-pulsatile and six pulsatile) examined high (750 cc/min) then low (450 cc/min) fixed flow before and after transient (30 s) ischaemia, while measuring brain vascular resistance and oxygen metabolism. Twelve subsequent pigs underwent 30 min of normothermic global brain ischaemia followed by either uncontrolled reperfusion with regular blood (n = 6) or pulsatile-controlled reperfusion (n = 6) before unclamping brain inflow vessels. Functional neurological deficit score (NDS; score: 0, normal; 500, brain death) was evaluated 24 h post-reperfusion. RESULTS High baseline flow rates with pulsatile and non-pulsatile perfusion before and after transient ischaemia maintained normal arterial pressures (90-100 mmHg), surface oxygen levels IN Vivo Optical Spectroscopy (INVOS) and oxygen uptake. In contrast, oxygen uptake fell after 30 s ischaemia at 450 cc/min non-pulsatile flow, but improved following pulsatile perfusion, despite its delivery at lower mean cerebral pressure. Uncontrolled (normal blood) reperfusion after 30 min of prolonged ischaemia, caused negligible INVOS O(2) uptake (<10-15%), raised conjugated dienes (CD; 1.75 ± 0.15 A(233 mn)), one early death, multiple seizures, high NDS (243 ± 16) and extensive cerebral infarcts (2,3,5-triphenyl tetrazolium chloride stain) and oedema (84.1 ± 0.6%). Conversely, pulsatile-controlled reperfusion pigs exhibited normal O(2) uptake, low CD levels (1.31 ± 0.07 A(233 mn); P < 0.01 versus uncontrolled reperfusion), no seizures and a low NDS (32 ± 14; P < 0.001 versus uncontrolled reperfusion); three showed complete recovery (NDS = 0) and all could sit and eat. Post-mortem brain oedema was minimal (81.1 ± 0.5; P < 0.001 versus uncontrolled reperfusion) and no infarctions occurred. CONCLUSIONS Pulsatile perfusion lowers cerebral vascular resistance and improves global O(2) uptake to potentially offset post-ischaemic oedema following high-pressure reperfusion. The irreversible functional and anatomic damage that followed uncontrolled reperfusion after a 30-min warm global brain ischaemia interval was reversed by pulsatile-controlled reperfusion, as its delivery resulted in consistent near complete neurological recovery and absent brain infarction.
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Affiliation(s)
- Bradley S Allen
- Department of Surgery, University of California, Los Angeles, CA, USA.
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Allen BS, Buckberg GD. Studies of isolated global brain ischaemia: I. Overview of irreversible brain injury and evolution of a new concept - redefining the time of brain death. Eur J Cardiothorac Surg 2012; 41:1132-7. [PMID: 22398465 DOI: 10.1093/ejcts/ezr315] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Despite advanced cardiac life support (ACLS), the mortality from sudden death after cardiac arrest is 85-95%, and becomes nearly 100% if ischaemia is prolonged, as occurs following unwitnessed arrest. Moreover, 33-50% of survivors following ACLS after witnessed arrest develop significant neurological dysfunction, and this rises to nearly 100% in the rare survivors of unwitnessed arrest. Although, whole body (cardiac) survival improves to 30% following recent use of emergency cardiopulmonary bypass, sustained neurological dysfunction remains a devastating and unresolved problem. Our studies suggest that both brain and whole body damage reflect an ischaemic/reperfusion injury that follows the present reperfusion methods that use normal blood, which we term 'uncontrolled reperfusion'. In contrast, we have previously introduced the term 'controlled reperfusion', which denotes controlling both the conditions (pressure, flow and temperature) as well as the composition (solution) of the reperfusate. Following prolonged ischaemia of the heart, lung and lower extremity, controlled reperfusion resulted in tissue recovery after ischaemic intervals previously thought to produce irreversible cellular injury. These observations underlie the current hypothesis that controlled reperfusion will become an effective treatment of the otherwise lethal injury of prolonged brain ischaemia, such as with unwitnessed arrest, and we tested this after 30 min of normothermic global brain ischaemia. This review, and the subsequent three studies will describe the evolution of the concept that controlled reperfusion will restore neurological function to the brain following prolonged (30 min) ischaemia. To provide a familiarity and rationale for these studies, this overview reviews the background and current treatment of sudden death, the concepts of controlled reperfusion, recent studies in the brain during whole body ischaemia, and then summarizes the three papers in this series on a new brain ischaemia model that endorses our hypothesis that controlled reperfusion allows complete neurological recovery following 30 min of normothermic global brain ischaemia. These findings may introduce innovative management approaches for sudden death, and perhaps stroke, because the brain is completely salvageable following ischaemic times thought previously to produce infarction.
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Affiliation(s)
- Bradley S Allen
- Department of Surgery, University of California, Los Angeles, CA, USA.
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Jung JS, Son KH, Ahn CB, Lee JJ, Son HS, Sun K. Analysis of pulsatile and nonpulsatile blood flow effects in different degrees of stenotic vasculature. Artif Organs 2011; 35:1118-23. [PMID: 22023148 DOI: 10.1111/j.1525-1594.2011.01361.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Vessel lumens that have been chronically narrowed by atherosclerosis should be increased in flow velocity and intrastenotic area pressure to maintain an equal flow. This might be followed by a decrease in hemodynamic energy, leading to a reduction of tissue perfusion. In this study, we compared hemodynamic energies according to degrees of stenotic vasculature between pulsatile flow and nonpulsatile flow. Cannuale with 25, 50, and 75% diameter stenosis (DS) were located at the outlet cannula. Using the Korea Hybrid ventricular assist device (KH-VAD) (pulsatile pump: group A) and Biopump (nonpulsatile pump: group B), constant flow of 2 L/min was maintained then real-time flow and velocity in the proximal and distal part of the stenotic cannula were measured. The hemodynamic energies of two groups were compared. At 75% DS, proximal energy equivalent pressure (EEP) delivered to the distal end was only 41.9% (group A) and 42.5% (group B). As the percent EEP fell below 10%, pulsatility disappeared from the 50% stenosis in group A. The surplus hemodynamic energy (SHE) of group B at all degrees of stenosis must have been 0, which was also the case of group A at 75% stenosis. This research evaluated the hemodynamic energy on various degrees of DS in both pulsatile and nonpulsatile flow with mock system. Using a pulsatile pump, pulsatility disappeared above 50% DS while hemodynamic energy was maintained. Therefore, our results suggest that pulsatile flow has a better effect than nonpulsatile flow in reserving hemodynamic energy after stenotic lesion.
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Affiliation(s)
- Jae Seung Jung
- Department of Thoracic and Cardiovascular Surgery, Anam Hospital, Korea University Medical Center, Seoul, Korea
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Abstract
Extra hemodynamic energy is one of the major benefits of pulsatile flow, improving blood flow to vital organs. But most (80%) of the hemodynamic energy generated from pulsatile flow is damped by the extracorporeal circuit. Most models devised to minimize hemodynamic energy loss have been in vitro pediatric models. The purpose of this study was to measure hemodynamic energy in different vessels of different organs with an in vivo adult swine model. An extracorporeal circuit was constructed for seven Yorkshire swine using a pulsatile pump (Twin-Pulse Life Support). The mean arterial pressure (MAP), energy equivalent pressure (EEP), and surplus hemodynamic energy (SHE) at the renal artery, carotid artery, aortic cannula site, and postoxygenator site were measured simultaneously before starting the pump and at the pump rates of 25, 35, and 45 bpm. The MAP of the renal or carotid artery was 40.0%-51.2% of the postoxygenator site. The EEP and SHE of both arteries were 11.6%-13.0% and 5.5%-7.4% of the postoxygenator site, respectively. The MAP and EEP of both arteries after starting the pump were lower than at baseline. The SHE of the renal artery after starting the pump was significantly higher than at baseline. The SHE of the carotid artery increased substantially after starting the pump although not statistically significantly. There was a significant hemodynamic energy loss in both arterial sites compared with the postoxygenator site. Also, a difference in hemodynamic energy loss was observed in vessel-to-vessel or vessel-to-circuit site comparison. This difference creates a bias in studying pulsatility and its effects. Therefore, the measurement method of hemodynamic energy must be standardized and the measurement site clarified to yield accurate study results.
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Undar A. International conference on pediatric mechanical circulatory support systems and pediatric cardiopulmonary perfusion: outcomes and future directions. ASAIO J 2008; 54:141-6. [PMID: 18356645 PMCID: PMC2646197 DOI: 10.1097/mat.0b013e318167afdd] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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