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Evans RG, Cochrane AD, Hood SG, Marino B, Iguchi N, Bellomo R, McCall PR, Okazaki N, Jufar AH, Miles LF, Furukawa T, Ow CPC, Raman J, May CN, Lankadeva YR. Differential responses of cerebral and renal oxygenation to altered perfusion conditions during experimental cardiopulmonary bypass in sheep. Clin Exp Pharmacol Physiol 2024; 51:e13852. [PMID: 38452756 DOI: 10.1111/1440-1681.13852] [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] [Received: 10/15/2023] [Revised: 01/23/2024] [Accepted: 02/13/2024] [Indexed: 03/09/2024]
Abstract
We tested whether the brain and kidney respond differently to cardiopulmonary bypass (CPB) and to changes in perfusion conditions during CPB. Therefore, in ovine CPB, we assessed regional cerebral oxygen saturation (rSO2 ) by near-infrared spectroscopy and renal cortical and medullary tissue oxygen tension (PO2 ), and, in some protocols, brain tissue PO2 , by phosphorescence lifetime oximetry. During CPB, rSO2 correlated with mixed venous SO2 (r = 0.78) and brain tissue PO2 (r = 0.49) when arterial PO2 was varied. During the first 30 min of CPB, brain tissue PO2 , rSO2 and renal cortical tissue PO2 did not fall, but renal medullary tissue PO2 did. Nevertheless, compared with stable anaesthesia, during stable CPB, rSO2 (66.8 decreasing to 61.3%) and both renal cortical (90.8 decreasing to 43.5 mm Hg) and medullary (44.3 decreasing to 19.2 mm Hg) tissue PO2 were lower. Both rSO2 and renal PO2 increased when pump flow was increased from 60 to 100 mL kg-1 min-1 at a target arterial pressure of 70 mm Hg. They also both increased when pump flow and arterial pressure were increased simultaneously. Neither was significantly altered by partially pulsatile flow. The vasopressor, metaraminol, dose-dependently decreased rSO2 , but increased renal cortical and medullary PO2 . Increasing blood haemoglobin concentration increased rSO2 , but not renal PO2 . We conclude that both the brain and kidney are susceptible to hypoxia during CPB, which can be alleviated by increasing pump flow, even without increasing arterial pressure. However, increasing blood haemoglobin concentration increases brain, but not kidney oxygenation, whereas vasopressor support with metaraminol increases kidney, but not brain oxygenation.
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Affiliation(s)
- Roger G Evans
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria, Australia
- Pre-clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Andrew D Cochrane
- Department of Cardiothoracic Surgery, Monash Health and Department of Surgery (School of Clinical Sciences at Monash Health), Monash University, Melbourne, Victoria, Australia
| | - Sally G Hood
- Pre-clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Bruno Marino
- Cellsaving and Perfusion Resources, Melbourne, Victoria, Australia
| | - Naoya Iguchi
- Pre-clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia
- Department of Anesthesiology and Intensive Care Medicine, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Rinaldo Bellomo
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria, Australia
- Department of Intensive Care, Austin Health, Heidelberg, Victoria, Australia
- Department of Critical Care, Melbourne Medical School, University of Melbourne, Victoria, Australia
| | - Peter R McCall
- Department of Critical Care, Melbourne Medical School, University of Melbourne, Victoria, Australia
- Department of Anaesthesia, Austin Health, Heidelberg, Victoria, Australia
| | - Nobuki Okazaki
- Pre-clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia
- Department of Anesthesiology and Resuscitology, Okayama University, Okayama, Japan
| | - Alemayehu H Jufar
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria, Australia
- Pre-clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Lachlan F Miles
- Pre-clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia
- Department of Critical Care, Melbourne Medical School, University of Melbourne, Victoria, Australia
- Department of Anaesthesia, Austin Health, Heidelberg, Victoria, Australia
| | - Taku Furukawa
- Pre-clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Connie P C Ow
- Pre-clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Jaishankar Raman
- Department of Intensive Care, Austin Health, Heidelberg, Victoria, Australia
- Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Victoria, Australia
| | - Clive N May
- Pre-clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia
- Department of Critical Care, Melbourne Medical School, University of Melbourne, Victoria, Australia
| | - Yugeesh R Lankadeva
- Pre-clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia
- Department of Critical Care, Melbourne Medical School, University of Melbourne, Victoria, Australia
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Sieminski M, Szaruta-Raflesz K, Szypenbejl J, Krzyzaniak K. Potential Neuroprotective Role of Melatonin in Sepsis-Associated Encephalopathy Due to Its Scavenging and Anti-Oxidative Properties. Antioxidants (Basel) 2023; 12:1786. [PMID: 37760089 PMCID: PMC10525116 DOI: 10.3390/antiox12091786] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/08/2023] [Accepted: 09/20/2023] [Indexed: 09/29/2023] Open
Abstract
Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. The brain is one of the organs involved in sepsis, and sepsis-induced brain injury manifests as sepsis-associated encephalopathy (SAE). SAE may be present in up to 70% of septic patients. SAE has a very wide spectrum of clinical symptoms, ranging from mild behavioral changes through cognitive disorders to disorders of consciousness and coma. The presence of SAE increases mortality in the population of septic patients and may lead to chronic cognitive dysfunction in sepsis survivors. Therefore, therapeutic interventions with neuroprotective effects in sepsis are needed. Melatonin, a neurohormone responsible for the control of circadian rhythms, exerts many beneficial physiological effects. Its anti-inflammatory and antioxidant properties are well described. It is considered a potential therapeutic factor in sepsis, with positive results from studies on animal models and with encouraging results from the first human clinical trials. With its antioxidant and anti-inflammatory potential, it may also exert a neuroprotective effect in sepsis-associated encephalopathy. The review presents data on melatonin as a potential drug in SAE in the wider context of the pathophysiology of SAE and the specific actions of the pineal neurohormone.
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Affiliation(s)
- Mariusz Sieminski
- Department of Emergency Medicine, Medical University of Gdansk, 80-214 Gdansk, Poland; (K.S.-R.); (K.K.)
| | | | - Jacek Szypenbejl
- Department of Emergency Medicine, Medical University of Gdansk, 80-214 Gdansk, Poland; (K.S.-R.); (K.K.)
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Jufar AH, Evans RG, May CN, Hood SG, Betrie AH, Trask‐Marino A, Bellomo R, Lankadeva YR. The effects of recruitment of renal functional reserve on renal cortical and medullary oxygenation in non-anesthetized sheep. Acta Physiol (Oxf) 2023; 237:e13919. [PMID: 36598336 PMCID: PMC10909474 DOI: 10.1111/apha.13919] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 11/18/2022] [Accepted: 01/02/2023] [Indexed: 01/05/2023]
Abstract
AIM Recruitment of renal functional reserve (RFR) with amino acid loading increases renal blood flow and glomerular filtration rate. However, its effects on renal cortical and medullary oxygenation have not been determined. Accordingly, we tested the effects of recruitment of RFR on renal cortical and medullary oxygenation in non-anesthetized sheep. METHODS Under general anesthesia, we instrumented 10 sheep to enable subsequent continuous measurements of systemic and renal hemodynamics, renal oxygen delivery and consumption, and cortical and medullary tissue oxygen tension (PO2 ). We then measured the effects of recruitment of RFR with an intravenous infusion of 500 ml of a clinically used amino acid solution (10% Synthamin® 17) in the non-anesthetized state. RESULTS Compared with baseline, Synthamin® 17 infusion significantly increased renal oxygen delivery mean ± SD maximum increase: (from 0.79 ± 0.17 to 1.06 ± 0.16 ml/kg/min, p < 0.001), renal oxygen consumption (from 0.08 ± 0.01 to 0.15 ± 0.02 ml/kg/min, p < 0.001), and glomerular filtration rate (+45.2 ± 2.7%, p < 0.001). Renal cortical tissue PO2 increased by a maximum of 26.4 ± 1.1% (p = 0.001) and medullary tissue PO2 increased by a maximum of 23.9 ± 2.8% (p = 0. 001). CONCLUSIONS In non-anesthetized healthy sheep, recruitment of RFR improved renal cortical and medullary oxygenation. These observations might have implications for the use of recruitment of RFR for diagnostic and therapeutic purposes.
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Affiliation(s)
- Alemayehu H. Jufar
- Pre‐Clinical Critical Care UnitFlorey Institute of Neuroscience and Mental Health, University of MelbourneMelbourneVictoriaAustralia
- Cardiovascular Disease Program, Department of PhysiologyBiomedicine Discovery Institute, Monash UniversityMelbourneVictoriaAustralia
| | - Roger G. Evans
- Pre‐Clinical Critical Care UnitFlorey Institute of Neuroscience and Mental Health, University of MelbourneMelbourneVictoriaAustralia
- Cardiovascular Disease Program, Department of PhysiologyBiomedicine Discovery Institute, Monash UniversityMelbourneVictoriaAustralia
| | - Clive N. May
- Pre‐Clinical Critical Care UnitFlorey Institute of Neuroscience and Mental Health, University of MelbourneMelbourneVictoriaAustralia
- Department of Critical CareMelbourne Medical School, University of MelbourneMelbourneVictoriaAustralia
| | - Sally G. Hood
- Pre‐Clinical Critical Care UnitFlorey Institute of Neuroscience and Mental Health, University of MelbourneMelbourneVictoriaAustralia
| | - Ashenafi H. Betrie
- Pre‐Clinical Critical Care UnitFlorey Institute of Neuroscience and Mental Health, University of MelbourneMelbourneVictoriaAustralia
- Melbourne Dementia Research CentreFlorey Institute of Neuroscience and Mental Health, The University of MelbourneMelbourneVictoriaAustralia
| | - Anton Trask‐Marino
- Pre‐Clinical Critical Care UnitFlorey Institute of Neuroscience and Mental Health, University of MelbourneMelbourneVictoriaAustralia
| | - Rinaldo Bellomo
- Pre‐Clinical Critical Care UnitFlorey Institute of Neuroscience and Mental Health, University of MelbourneMelbourneVictoriaAustralia
- Department of Critical CareMelbourne Medical School, University of MelbourneMelbourneVictoriaAustralia
| | - Yugeesh R. Lankadeva
- Pre‐Clinical Critical Care UnitFlorey Institute of Neuroscience and Mental Health, University of MelbourneMelbourneVictoriaAustralia
- Department of Critical CareMelbourne Medical School, University of MelbourneMelbourneVictoriaAustralia
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Vintrych P, Al-Obeidallah M, Horák J, Chvojka J, Valešová L, Nalos L, Jarkovská D, Matějovič M, Štengl M. Modeling sepsis, with a special focus on large animal models of porcine peritonitis and bacteremia. Front Physiol 2023; 13:1094199. [PMID: 36703923 PMCID: PMC9871395 DOI: 10.3389/fphys.2022.1094199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 12/28/2022] [Indexed: 01/12/2023] Open
Abstract
Infectious diseases, which often result in deadly sepsis or septic shock, represent a major global health problem. For understanding the pathophysiology of sepsis and developing new treatment strategies, reliable and clinically relevant animal models of the disease are necessary. In this review, two large animal (porcine) models of sepsis induced by either peritonitis or bacteremia are introduced and their strong and weak points are discussed in the context of clinical relevance and other animal models of sepsis, with a special focus on cardiovascular and immune systems, experimental design, and monitoring. Especially for testing new therapeutic strategies, the large animal (porcine) models represent a more clinically relevant alternative to small animal models, and the findings obtained in small animal (transgenic) models should be verified in these clinically relevant large animal models before translation to the clinical level.
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Affiliation(s)
- Pavel Vintrych
- Department of Cardiology, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia
| | - Mahmoud Al-Obeidallah
- Department of Physiology, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia
| | - Jan Horák
- Department of Internal Medicine I, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia,Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia
| | - Jiří Chvojka
- Department of Internal Medicine I, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia,Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia
| | - Lenka Valešová
- Department of Internal Medicine I, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia,Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia
| | - Lukáš Nalos
- Department of Physiology, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia,Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia
| | - Dagmar Jarkovská
- Department of Physiology, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia,Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia
| | - Martin Matějovič
- Department of Internal Medicine I, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia,Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia
| | - Milan Štengl
- Department of Physiology, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia,Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Prague, Czechia,*Correspondence: Milan Štengl,
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Jufar AH, May CN, Evans RG, Cochrane AD, Marino B, Hood SG, McCall PR, Bellomo R, Lankadeva YR. Influence of moderate-hypothermia on renal and cerebral haemodynamics and oxygenation during experimental cardiopulmonary bypass in sheep. Acta Physiol (Oxf) 2022; 236:e13860. [PMID: 35862484 DOI: 10.1111/apha.13860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 07/11/2022] [Accepted: 07/18/2022] [Indexed: 11/01/2022]
Abstract
AIM Cardiac surgery requiring cardiopulmonary bypass (CPB) can result in renal and cerebral injury. Intra-operative tissue hypoxia could contribute to such organ injury. Hypothermia, however, may alleviate organ hypoxia. Therefore, we tested whether moderate-hypothermia (30o C) improves cerebral and renal tissue perfusion and oxygenation during ovine CPB. METHODS Ten sheep were studied while conscious, under stable anaesthesia and during 3 hours of CPB. In a randomised within-animal cross-over design, 5 sheep commenced CPB at a target body temperature of 30 o C (moderate-hypothermia). After 90 minutes, body temperature was increased to 36 o C (standard-procedure). The remaining 5 sheep were randomised to the opposite order of target body temperature. RESULTS Compared with the standard-procedure, moderately-hypothermic CPB reduced renal oxygen delivery (-34.8 ± 19.6%, P = 0.003) and renal oxygen consumption (-42.7 ± 35.2%, P = 0.04). Nevertheless, moderately-hypothermic CPB did not significantly alter either renal cortical or medullary tissue PO2 . Moderately-hypothermic CPB also did not significantly alter cerebral perfusion, cerebral tissue PO2 , or cerebral oxygen saturation compared with the standard-procedure. Compared with anaesthetised state, standard-procedure reduced renal medullary PO2 (-21.0 ± 13.8 mmHg, P = 0.014) and cerebral oxygen saturation (65.0 ± 7.0 to 55.4 ± 9.6%, P = 0.022) but did not significantly alter either renal cortical or cerebral PO2 . CONCLUSION Ovine experimental CPB leads to renal medullary tissue hypoxia. Moderately-hypothermic CPB did not improve cerebral or renal tissue oxygenation. In the kidney, this is probably because renal tissue oxygen consumption is matched by reduced renal oxygen delivery.
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Affiliation(s)
- Alemayehu H Jufar
- Pre-Clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia.,Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria, Australia
| | - Clive N May
- Pre-Clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia.,Department of Critical Care, Melbourne Medical School, University of Melbourne, Victoria, Australia
| | - Roger G Evans
- Pre-Clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia.,Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria, Australia
| | - Andrew D Cochrane
- Department of Cardiothoracic Surgery, Monash Health and Department of Surgery (School of Clinical Sciences at Monash Health), Monash University, Melbourne, Victoria, Australia
| | - Bruno Marino
- Cellsaving and Perfusion Resources, Melbourne, Victoria, Australia
| | - Sally G Hood
- Pre-Clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Peter R McCall
- Department of Anaesthesia, Austin Health, Heidelberg, Victoria, Australia
| | - Rinaldo Bellomo
- Pre-Clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia.,Department of Critical Care, Melbourne Medical School, University of Melbourne, Victoria, Australia
| | - Yugeesh R Lankadeva
- Pre-Clinical Critical Care Unit, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Victoria, Australia.,Department of Critical Care, Melbourne Medical School, University of Melbourne, Victoria, Australia
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Taccone FS, Su F, He X, Peluso L, Donadello K, Scolletta S, De Backer D, Vincent JL. Effects of Reversal of Hypotension on Cerebral Microcirculation and Metabolism in Experimental Sepsis. Biomedicines 2022; 10:biomedicines10040923. [PMID: 35453673 PMCID: PMC9032351 DOI: 10.3390/biomedicines10040923] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 04/11/2022] [Accepted: 04/15/2022] [Indexed: 12/28/2022] Open
Abstract
The effects of reversal of hypotension on the cerebral microcirculation, oxygenation, and metabolism in septic shock remain unclear. In 12 sheep, peritonitis was induced by injection of feces into the abdominal cavity. At the onset of septic shock (mean arterial pressure (MAP) < 65 mmHg, unresponsive to fluid challenge), a norepinephrine infusion was titrated in eight sheep to restore a MAP ≥ 75 mmHg; the other four sheep were kept hypotensive. The microcirculation of the cerebral cortex was evaluated using side-stream dark-field video-microscopy. Brain partial pressure of oxygen (PbtO2) was measured, and cerebral metabolism was assessed using microdialysis. All animals developed septic shock after a median of 15 (14−19) h. When MAP was raised using norepinephrine, the PbtO2 increased significantly (from 41 ± 4 to 55 ± 5 mmHg), and the cerebral lactate/pyruvate ratio decreased (from 47 ± 13 to 28 ± 4) compared with values at shock onset. Changes in the microcirculation were unchanged with restoration of MAP and the glutamate increased further (from 17 ± 11 to 23 ± 16 μM), as it did in the untreated animals. In septic shock, the correction of hypotension with vasopressors may improve cerebral oxygenation but does not reverse the alterations in brain microcirculation or cerebral metabolism.
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Affiliation(s)
- Fabio Silvio Taccone
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium; (L.P.); (K.D.); (J.-L.V.)
- Laboratoire Experimental des Soins Intensifs, Department of Intensive Care, Hôpital Erasme, Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium; (F.S.); (X.H.); (S.S.); (D.D.B.)
- Correspondence: ; Tel.: +32-25-554-445
| | - Fuhong Su
- Laboratoire Experimental des Soins Intensifs, Department of Intensive Care, Hôpital Erasme, Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium; (F.S.); (X.H.); (S.S.); (D.D.B.)
| | - Xinrong He
- Laboratoire Experimental des Soins Intensifs, Department of Intensive Care, Hôpital Erasme, Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium; (F.S.); (X.H.); (S.S.); (D.D.B.)
| | - Lorenzo Peluso
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium; (L.P.); (K.D.); (J.-L.V.)
| | - Katia Donadello
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium; (L.P.); (K.D.); (J.-L.V.)
- Unit of Anesthesiology and Intensive Care B, AOUI-University Hospital Integrated Trust of Verona, University of Verona, 37129 Verona, Italy
| | - Sabino Scolletta
- Laboratoire Experimental des Soins Intensifs, Department of Intensive Care, Hôpital Erasme, Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium; (F.S.); (X.H.); (S.S.); (D.D.B.)
- Anestesia e Terapia Intensiva, Azienda Ospedaliera Universitaria Senese, 53100 Siena, Italy
| | - Daniel De Backer
- Laboratoire Experimental des Soins Intensifs, Department of Intensive Care, Hôpital Erasme, Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium; (F.S.); (X.H.); (S.S.); (D.D.B.)
- Intensive Care Department, CHIREC Hospitals, 1160 Brussels, Belgium
| | - Jean-Louis Vincent
- Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium; (L.P.); (K.D.); (J.-L.V.)
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