1
|
Valerianova A, Mlcek M, Kittnar O, Grus T, Tejkl L, Lejsek V, Malik J. A large arteriovenous fistula steals a considerable part of systemic blood flow during veno-arterial extracorporeal circulation support in a porcine model. Front Physiol 2023; 14:1109524. [PMID: 37497434 PMCID: PMC10366375 DOI: 10.3389/fphys.2023.1109524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Accepted: 06/30/2023] [Indexed: 07/28/2023] Open
Abstract
Background: Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is one of the most frequently used mechanical circulatory support devices. Distribution of extracorporeal membrane oxygenation flow depends (similarly as the cardiac output distribution) on regional vascular resistance. Arteriovenous fistulas (AVFs), used frequently as hemodialysis access, represent a low-resistant circuit which steals part of the systemic perfusion. We tested the hypothesis that the presence of a large Arteriovenous fistulas significantly changes organ perfusion during a partial and a full Veno-arterial extracorporeal membrane oxygenation support. Methods: The protocol was performed on domestic female pigs held under general anesthesia. Cannulas for Veno-arterial extracorporeal membrane oxygenation were inserted into femoral artery and vein. The Arteriovenous fistulas was created using another two high-diameter extracorporeal membrane oxygenation cannulas inserted in the contralateral femoral artery and vein. Catheters, flow probes, flow wires and other sensors were placed for continuous monitoring of haemodynamics and organ perfusion. A stepwise increase in extracorporeal membrane oxygenation flow was considered under beating heart and ventricular fibrillation (VF) with closed and opened Arteriovenous fistulas. Results: Opening of a large Arteriovenous fistulas (blood flow ranging from 1.1 to 2.2 L/min) resulted in decrease of effective systemic blood flow by 17%-30% (p < 0.01 for all steps). This led to a significant decrease of carotid artery flow (ranging from 13% to 25% after Arteriovenous fistulas opening) following VF and under partial extracorporeal membrane oxygenation support. Cerebral tissue oxygenation measured by near infrared spectroscopy also decreased significantly in all steps. These changes occurred even with maintained perfusion pressure. Changes in coronary artery flow were driven by changes in the native cardiac output. Conclusion: A large arteriovenous fistula can completely counteract Veno-arterial extracorporeal membrane oxygenation support unless maximal extracorporeal membrane oxygenation flow is applied. Cerebral blood flow and oxygenation are mainly compromised by the effect of the Arteriovenous fistulas. These effects could influence brain function in patients with Arteriovenous fistulas on Veno-arterial extracorporeal membrane oxygenation.
Collapse
Affiliation(s)
- A. Valerianova
- Third Department of Internal Medicine, First Faculty of Medicine, General University Hospital in Prague, Charles University in Prague, Prague, Czechia
- First Faculty of Medicine, Institute of Physiology, Charles University in Prague, Prague, Czechia
| | - M. Mlcek
- First Faculty of Medicine, Institute of Physiology, Charles University in Prague, Prague, Czechia
| | - O. Kittnar
- First Faculty of Medicine, Institute of Physiology, Charles University in Prague, Prague, Czechia
| | - T. Grus
- Second Surgical Clinic—Cardiovascular Surgery, First Faculty of Medicine, General University Hospital in Prague, Charles University in Prague, Prague, Czechia
| | - L. Tejkl
- First Faculty of Medicine, Institute of Physiology, Charles University in Prague, Prague, Czechia
| | - V. Lejsek
- Third Department of Internal Medicine, First Faculty of Medicine, General University Hospital in Prague, Charles University in Prague, Prague, Czechia
| | - J. Malik
- Third Department of Internal Medicine, First Faculty of Medicine, General University Hospital in Prague, Charles University in Prague, Prague, Czechia
| |
Collapse
|
2
|
Mlček M, Borges JB, Otáhal M, Alcala GC, Hladík D, Kuriščák E, Tejkl L, Amato M, Kittnar O. Real-time effects of lateral positioning on regional ventilation and perfusion in an experimental model of acute respiratory distress syndrome. Front Physiol 2023; 14:1113568. [PMID: 37020459 PMCID: PMC10067565 DOI: 10.3389/fphys.2023.1113568] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 03/01/2023] [Indexed: 03/22/2023] Open
Abstract
Low-volume lung injury encompasses local concentration of stresses in the vicinity of collapsed regions in heterogeneously ventilated lungs. We aimed to study the effects on ventilation and perfusion distributions of a sequential lateral positioning (30°) strategy using electrical impedance tomography imaging in a porcine experimental model of early acute respiratory distress syndrome (ARDS). We hypothesized that such strategy, including a real-time individualization of positive end-expiratory pressure (PEEP) whenever in lateral positioning, would provide attenuation of collapse in the dependent lung regions. A two-hit injury acute respiratory distress syndrome experimental model was established by lung lavages followed by injurious mechanical ventilation. Then, all animals were studied in five body positions in a sequential order, 15 min each: Supine 1; Lateral Left; Supine 2; Lateral Right; Supine 3. The following functional images were analyzed by electrical impedance tomography: ventilation distributions and regional lung volumes, and perfusion distributions. The induction of the acute respiratory distress syndrome model resulted in a marked fall in oxygenation along with low regional ventilation and compliance of the dorsal half of the lung (gravitational-dependent in supine position). Both the regional ventilation and compliance of the dorsal half of the lung greatly increased along of the sequential lateral positioning strategy, and maximally at its end. In addition, a corresponding improvement of oxygenation occurred. In conclusion, our sequential lateral positioning strategy, with sufficient positive end-expiratory pressure to prevent collapse of the dependent lung units during lateral positioning, provided a relevant diminution of collapse in the dorsal lung in a porcine experimental model of early acute respiratory distress syndrome.
Collapse
Affiliation(s)
- Mikuláš Mlček
- First Faculty of Medicine, Institute of Physiology, Charles University, Prague, Czechia
| | - João Batista Borges
- First Faculty of Medicine, Institute of Physiology, Charles University, Prague, Czechia
- *Correspondence: João Batista Borges,
| | - Michal Otáhal
- First Faculty of Medicine, Institute of Physiology, Charles University, Prague, Czechia
- Department of Anaesthesiology, Resuscitation and Intensive Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czechia
| | - Glasiele Cristina Alcala
- Pulmonology Division, Cardiopulmonary Department, Heart Institute, University of Sao Paulo, São Paulo, Brazil
| | - Dominik Hladík
- First Faculty of Medicine, Institute of Physiology, Charles University, Prague, Czechia
- Department of Anaesthesiology, Resuscitation and Intensive Medicine, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czechia
| | - Eduard Kuriščák
- First Faculty of Medicine, Institute of Physiology, Charles University, Prague, Czechia
| | - Leoš Tejkl
- First Faculty of Medicine, Institute of Physiology, Charles University, Prague, Czechia
| | - Marcelo Amato
- Pulmonology Division, Cardiopulmonary Department, Heart Institute, University of Sao Paulo, São Paulo, Brazil
| | - Otomar Kittnar
- First Faculty of Medicine, Institute of Physiology, Charles University, Prague, Czechia
| |
Collapse
|
3
|
KITTNAR O. Ten years of our translational research in the field of veno-arterial extracorporeal membrane oxygenation. Physiol Res 2022; 71:S163-S178. [PMID: 36647905 PMCID: PMC9906662 DOI: 10.33549/physiolres.934999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Extracorporeal life support is a treatment modality that provides prolonged blood circulation, gas exchange and can substitute functions of heart and lungs to provide urgent cardio-respiratory stabilization in patients with severe but potentially reversible cardiopulmonary failure refractory to conventional therapy. Generally, the therapy targets blood pressure, volume status, and end-organs perfusion. As there are significant differences in hemodynamic efficacy among different percutaneous circulatory support systems, it should be carefully considered when selecting the most appropriate circulatory support for specific medical conditions in individual patients. Despite severe metabolic and hemodynamic deterioration during prolonged cardiac arrest, venoarterial extracorporeal membrane oxygenation (VA ECMO) can rapidly revert otherwise fatal prognosis, thus carrying a potential for improvement in survival rate, which can be even improved by introduction of mild therapeutic hypothermia. In order to allow a rapid transfer of knowledge to clinical medicine two porcine models were developed for studying efficiency of the VA ECMO in treatments of acute cardiogenic shock and progressive chronic heart failure. These models allowed also an intensive research of adverse events accompanying a clinical use of VA ECMO and their possible compensations. The results indicated that in order to weaken the negative effects of increased afterload on the left ventricular function the optimal VA ECMO flow in cardiogenic shock should be as low as possible to allow adequate tissue perfusion. The left ventricle can be also unloaded by an ECG-synchronized pulsatile flow if using a novel pulsatile ECMO system. Thus, pulsatility of VA ECMO flow may improve coronary perfusion even under conditions of high ECMO blood flows. And last but not least, also the percutaneous balloon atrial septostomy is a very perspective method how to passively decompress overloaded left heart.
Collapse
Affiliation(s)
- Otomar KITTNAR
- Institute of Physiology of the First Faculty of Medicine, Charles University, Prague, Czech Republic
| |
Collapse
|
4
|
Peterson DM, Beal EW, Reader BF, Dumond C, Black SM, Whitson BA. Electrical Impedance as a Noninvasive Metric of Quality in Allografts Undergoing Normothermic Ex Vivo Lung Perfusion. ASAIO J 2022; 68:964-971. [PMID: 35067581 PMCID: PMC9247000 DOI: 10.1097/mat.0000000000001591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Ex vivo lung perfusion (EVLP) increases the pool of suitable organs for transplant by facilitating assessment and repair at normothermia, thereby improving identification of quality of marginal organs. However, there exists no current objective approach for assessing total organ edema. We sought to evaluate the use of electrical impedance as a metric to assess total organ edema in lungs undergoing EVLP. Adult porcine lungs (40 kg) underwent normothermic EVLP for 4 hours. To induce varying degrees of lung injury, the allografts were perfused with either Steen, a modified cell culture media, or 0.9% normal saline. Physiologic parameters (peak airway pressure and compliance), pulmonary artery and left atrial blood gases, and extravascular lung water measurements were evaluated over time. Wet-to-dry ratios were evaluated postperfusion. Modified Murray scoring was used to calculate lung injury. Impedance values were associated with lung injury scores ( p = 0.007). Peak airway pressure ( p = 0.01) and PaO 2 /FiO 2 ratios ( p = 0.005) were both significantly associated with reduced impedance. Compliance was not associated with impedance ( p = 0.07). Wet/dry ratios were significantly associated with impedance and Murray Scoring within perfusion groups of Steen, Saline, and Modified Cell Culture ( p = 0.0186, 0.0142, 0.0002, respectively). Electrical impedance offers a noninvasive modality for measuring lung quality as assessed by tissue edema in a porcine model of normothermic EVLP. Further studies evaluating the use of impedance to assess organ edema as a quality marker in human clinical models and abdominal organs undergoing ex vivo perfusion warrant investigation.
Collapse
Affiliation(s)
- Danielle M Peterson
- From the The Collaboration for Organ Perfusion, Protection, Engineering and Regeneration (COPPER) Laboratory, The Ohio State University, Columbus, Ohio
- The Ohio State University College of Medicine, Columbus, Ohio
- Penn State College of Medicine Department of Surgery, Hershey, Pennsylvania
| | - Eliza W Beal
- From the The Collaboration for Organ Perfusion, Protection, Engineering and Regeneration (COPPER) Laboratory, The Ohio State University, Columbus, Ohio
- The Ohio State University Wexner Medical Center Department of Surgery, Columbus Ohio
| | - Brenda F Reader
- From the The Collaboration for Organ Perfusion, Protection, Engineering and Regeneration (COPPER) Laboratory, The Ohio State University, Columbus, Ohio
- The Ohio State University Wexner Medical Center Department of Surgery, Columbus Ohio
| | - Curtis Dumond
- From the The Collaboration for Organ Perfusion, Protection, Engineering and Regeneration (COPPER) Laboratory, The Ohio State University, Columbus, Ohio
- The Ohio State University Wexner Medical Center Department of Surgery, Columbus Ohio
| | - Sylvester M Black
- From the The Collaboration for Organ Perfusion, Protection, Engineering and Regeneration (COPPER) Laboratory, The Ohio State University, Columbus, Ohio
- The Ohio State University Wexner Medical Center Department of Surgery, Columbus Ohio
| | - Bryan A Whitson
- From the The Collaboration for Organ Perfusion, Protection, Engineering and Regeneration (COPPER) Laboratory, The Ohio State University, Columbus, Ohio
- The Ohio State University Wexner Medical Center Department of Surgery, Columbus Ohio
| |
Collapse
|
5
|
Valerianova A, Mlcek M, Grus T, Malik J, Kittnar O. New Porcine Model of Arteriovenous Fistula Documents Increased Coronary Blood Flow at the Cost of Brain Perfusion. Front Physiol 2022; 13:881658. [PMID: 35574433 PMCID: PMC9091445 DOI: 10.3389/fphys.2022.881658] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 04/06/2022] [Indexed: 11/19/2022] Open
Abstract
Background: Arteriovenous fistulas (AVF) represent a low resistant circuit. It is known that their opening leads to decreased systemic vascular resistance, increased cardiac output and other hemodynamic changes. Possible competition of AVF and perfusion of other organs has been observed before, however the specific impact of AVF has not been elucidated yet. Previous animal models studied long-term changes associated with a surgically created high flow AVF. The aim of this study was to create a simple AVF model for the analysis of acute hemodynamic changes. Methods: Domestic female pigs weighing 62.6 ± 5.2 kg were used. All the experiments were held under general anesthesia. The AVF was created using high-diameter ECMO cannulas inserted into femoral artery and vein. Continuous hemodynamic monitoring was performed throughout the protocol. Near-infrared spectroscopy sensors, flow probes and flow wires were inserted to study brain and heart perfusion. Results: AVF blood flow was 2.1 ± 0.5 L/min, which represented around 23% of cardiac output. We observed increase in cardiac output (from 7.02 ± 2.35 L/min to 9.19 ± 2.99 L/min, p = 0.0001) driven dominantly by increased heart rate, increased pulmonary artery pressure, and associated right ventricular work. Coronary artery flow velocity rose. On the contrary, carotid artery flow and brain and muscle tissue oxygenation measured by NIRS decreased significantly. Conclusions: Our new non-surgical AVF model is reproducible and demonstrated an acute decrease of brain and muscle perfusion.
Collapse
Affiliation(s)
- Anna Valerianova
- 3rd Department of Internal Medicine, General University Hospital in Prague, 1st Faculty of Medicine, Charles University, Prague, Czechia.,Institute of Physiology, 1st Faculty of Medicine, Charles University, Prague, Czechia
| | - Mikulas Mlcek
- Institute of Physiology, 1st Faculty of Medicine, Charles University, Prague, Czechia
| | - Tomas Grus
- 2nd Surgical clinic, Cardiovascular Surgery, General University Hospital in Prague, 1st Faculty of Medicine, Charles University, Prague, Czechia
| | - Jan Malik
- 3rd Department of Internal Medicine, General University Hospital in Prague, 1st Faculty of Medicine, Charles University, Prague, Czechia
| | - Otomar Kittnar
- Institute of Physiology, 1st Faculty of Medicine, Charles University, Prague, Czechia
| |
Collapse
|
6
|
Shelton KT, Crowley J, Wiener-Kronish J. Prevention of Complications in the Cardiac Intensive Care Unit. J Cardiothorac Vasc Anesth 2021; 35:1930-1932. [PMID: 33653576 DOI: 10.1053/j.jvca.2021.01.049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 01/23/2021] [Indexed: 11/11/2022]
Affiliation(s)
- Kenneth T Shelton
- Department of Anesthesia, Critical Care and Pain Medicine; Corrigan Minehan Heart Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Jerome Crowley
- Department of Anesthesia, Critical Care and Pain Medicine; Corrigan Minehan Heart Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | | |
Collapse
|
7
|
Hála P, Kittnar O. Hemodynamic adaptation of heart failure to percutaneous venoarterial extracorporeal circulatory supports. Physiol Res 2020; 69:739-757. [PMID: 32901493 DOI: 10.33549/physiolres.934332] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Extracorporeal life support (ECLS) is a treatment modality that provides prolonged blood circulation, gas exchange and can partially support or fully substitute functions of heart and lungs in patients with severe but potentially reversible cardiopulmonary failure refractory to conventional therapy. Due to high-volume bypass, the extracorporeal flow is interacting with native cardiac output. The pathophysiology of circulation and ECLS support reveals significant effects on arterial pressure waveforms, cardiac hemodynamics, and myocardial perfusion. Moreover, it is still subject of research, whether increasing stroke work caused by the extracorporeal flow is accompanied by adequate myocardial oxygen supply. The left ventricular (LV) pressure-volume mechanics are reflecting perfusion and loading conditions and these changes are dependent on the degree of the extracorporeal blood flow. By increasing the afterload, artificial circulation puts higher demands on heart work with increasing myocardial oxygen consumption. Further, this can lead to LV distention, pulmonary edema, and progression of heart failure. Multiple methods of LV decompression (atrial septostomy, active venting, intra-aortic balloon pump, pulsatility of flow) have been suggested to relieve LV overload but the main risk factors still remain unclear. In this context, it has been recommended to keep the rate of circulatory support as low as possible. Also, utilization of detailed hemodynamic monitoring has been suggested in order to avoid possible harm from excessive extracorporeal flow.
Collapse
Affiliation(s)
- P Hála
- Department of Physiology, First Faculty of Medicine, Charles University, Prague, Czech Republic.
| | | |
Collapse
|