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Maruniak S, Loskutov O, Swol J, Todurov B. Factors associated with acute kidney injury after on-pump coronary artery bypass grafting. J Cardiothorac Surg 2024; 19:598. [PMID: 39380008 PMCID: PMC11459944 DOI: 10.1186/s13019-024-03103-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2024] [Accepted: 09/15/2024] [Indexed: 10/10/2024] Open
Abstract
BACKGROUND Acute kidney injury (AKI) frequently occurs as a complication of cardiac surgery and cardiopulmonary bypass (CPB). Its prevalence and severity are determined by various preoperative and intraoperative factors. The aim of this study was to examine the risk factors for AKI following on-pump coronary artery bypass grafting (CABG). METHODS A retrospective analysis of clinical records from a single medical center was performed. The primary determinant for AKI analysis was the creatinine-level changes within the first 48 h after surgery. Records of 120 patients from a prospective cohort study were examined. RESULTS An AKI incidence of 26% occurred in the study cohort. The univariate analysis revealed that patients who developed AKI had notably higher EuroSCORE II values (2.00 ± 0.98 vs. 1.49 ± 0.74, p = 0.006) and higher initial levels of urea (7.62 ± 2.94 vs. 6.12 ± 1.71, p = 0.002) and creatinine (0.108 ± 0.039 vs. 0.091 ± 0.016, p = 0.003). Additionally, they exhibited a more frequent occurrence of initial albumin levels below 40 g/l (9 (34.6%) vs. 11 (14.9%) cases, p = 0.030) and a lower initial hemoglobin level (137.8 ± 13.2 g/l vs. 146.6 ± 13.6 g/l, p = 0.005) in comparison to patients without this complication. Moreover, those with AKI had a significantly longer hospital stay duration (14.3 ± 5.45 days vs. 12.6 ± 3.05 days, p = 0.048). Logistic regression indicated one risk factor, oxygen delivery during CPB, that correlated with the onset of AKI in the early postoperative period. CONCLUSION The prevalence of AKI was higher among patients with a higher EuroSCORE II, lower preoperative hemoglobin, increased preoperative levels of creatinine and urea, infrequent albumin levels below 40 g/L, diminished oxygen delivery during CPB, and greater need for RBC transfusion and furosemide, but it did not correlate with the duration of CPB.
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Affiliation(s)
- Stepan Maruniak
- Department of Respiratory Medicine, Paracelsus Medical University, Prof.-Ernst- Nathan-Str. 1, 90419, Nuremberg, Germany.
- Department of Extracorporeal Methods of Treatment, Heart Institute Ministry of Health of Ukraine, Bratyslavska str. 5A, Kyiv, 02166, Ukraine.
- Department of Anaesthesiology and Intensive Care, PL Shupyk National Healthcare University of Ukraine, Bratyslavska str. 3 A, Kyiv, 02166, Ukraine.
| | - Oleh Loskutov
- Department of Extracorporeal Methods of Treatment, Heart Institute Ministry of Health of Ukraine, Bratyslavska str. 5A, Kyiv, 02166, Ukraine
- Department of Anaesthesiology and Intensive Care, PL Shupyk National Healthcare University of Ukraine, Bratyslavska str. 3 A, Kyiv, 02166, Ukraine
| | - Justyna Swol
- Department of Respiratory Medicine, Paracelsus Medical University, Prof.-Ernst- Nathan-Str. 1, 90419, Nuremberg, Germany
| | - Borys Todurov
- Department of Extracorporeal Methods of Treatment, Heart Institute Ministry of Health of Ukraine, Bratyslavska str. 5A, Kyiv, 02166, Ukraine
- Department of Anaesthesiology and Intensive Care, PL Shupyk National Healthcare University of Ukraine, Bratyslavska str. 3 A, Kyiv, 02166, Ukraine
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2
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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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3
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Arynov A, Kaidarova D, Kabon B. Alternative blood transfusion triggers: a narrative review. BMC Anesthesiol 2024; 24:71. [PMID: 38395758 PMCID: PMC10885388 DOI: 10.1186/s12871-024-02447-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 02/07/2024] [Indexed: 02/25/2024] Open
Abstract
BACKGROUND Anemia, characterized by low hemoglobin levels, is a global public health concern. Anemia is an independent factor worsening outcomes in various patient groups. Blood transfusion has been the traditional treatment for anemia; its triggers, primarily based on hemoglobin levels; however, hemoglobin level is not always an ideal trigger for blood transfusion. Additionally, blood transfusion worsens clinical outcomes in certain patient groups. This narrative review explores alternative triggers for red blood cell transfusion and their physiological basis. MAIN TEXT The review delves into the physiology of oxygen transport and highlights the limitations of using hemoglobin levels alone as transfusion trigger. The main aim of blood transfusion is to optimize oxygen delivery, necessitating an individualized approach based on clinical signs of anemia and the balance between oxygen delivery and consumption, reflected by the oxygen extraction rate. The narrative review covers different alternative triggers. It presents insights into their diagnostic value and clinical applications, emphasizing the need for personalized transfusion strategies. CONCLUSION Anemia and blood transfusion are significant factors affecting patient outcomes. While restrictive transfusion strategies are widely recommended, they may not account for the nuances of specific patient populations. The search for alternative transfusion triggers is essential to tailor transfusion therapy effectively, especially in patients with comorbidities or unique clinical profiles. Investigating alternative triggers not only enhances patient care by identifying more precise indicators but also minimizes transfusion-related risks, optimizes blood product utilization, and ensures availability when needed. Personalized transfusion strategies based on alternative triggers hold the potential to improve outcomes in various clinical scenarios, addressing anemia's complex challenges in healthcare. Further research and evidence are needed to refine these alternative triggers and guide their implementation in clinical practice.
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Affiliation(s)
- Ardak Arynov
- Department of Anesthesiology and Intensive Care, Kazakh Institute of Oncology and Radiology, Abay av. 91, Almaty, Kazakhstan.
| | - Dilyara Kaidarova
- Kazakh Institute of Oncology and Radiology, Abay av. 91, Almaty, Kazakhstan
| | - Barbara Kabon
- Department of Anaesthesia, General Intensive Medicine and Pain Medicine Medical, University of Vienna, Spitalgasse 23, 1090, Vienna, Austria
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Chae SY, Kim Y, Park CW. Oxidative Stress Induced by Lipotoxicity and Renal Hypoxia in Diabetic Kidney Disease and Possible Therapeutic Interventions: Targeting the Lipid Metabolism and Hypoxia. Antioxidants (Basel) 2023; 12:2083. [PMID: 38136203 PMCID: PMC10740440 DOI: 10.3390/antiox12122083] [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: 11/09/2023] [Revised: 11/26/2023] [Accepted: 12/01/2023] [Indexed: 12/24/2023] Open
Abstract
Oxidative stress, a hallmark pathophysiological feature in diabetic kidney disease (DKD), arises from the intricate interplay between pro-oxidants and anti-oxidants. While hyperglycemia has been well established as a key contributor, lipotoxicity emerges as a significant instigator of oxidative stress. Lipotoxicity encompasses the accumulation of lipid intermediates, culminating in cellular dysfunction and cell death. However, the mechanisms underlying lipotoxic kidney injury in DKD still require further investigation. The key role of cell metabolism in the maintenance of cell viability and integrity in the kidney is of paramount importance to maintain proper renal function. Recently, dysfunction in energy metabolism, resulting from an imbalance in oxygen levels in the diabetic condition, may be the primary pathophysiologic pathway driving DKD. Therefore, we aim to shed light on the pivotal role of oxidative stress related to lipotoxicity and renal hypoxia in the initiation and progression of DKD. Multifaceted mechanisms underlying lipotoxicity, including oxidative stress with mitochondrial dysfunction, endoplasmic reticulum stress activated by the unfolded protein response pathway, pro-inflammation, and impaired autophagy, are delineated here. Also, we explore potential therapeutic interventions for DKD, targeting lipotoxicity- and hypoxia-induced oxidative stress. These interventions focus on ameliorating the molecular pathways of lipid accumulation within the kidney and enhancing renal metabolism in the face of lipid overload or ameliorating subsequent oxidative stress. This review highlights the significance of lipotoxicity, renal hypoxia-induced oxidative stress, and its potential for therapeutic intervention in DKD.
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Affiliation(s)
- Seung Yun Chae
- Division of Nephrology, Department of Internal Medicine, Seoul St. Mary’s Hospital, The College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul 06591, Republic of Korea; (S.Y.C.); (Y.K.)
| | - Yaeni Kim
- Division of Nephrology, Department of Internal Medicine, Seoul St. Mary’s Hospital, The College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul 06591, Republic of Korea; (S.Y.C.); (Y.K.)
| | - Cheol Whee Park
- Division of Nephrology, Department of Internal Medicine, Seoul St. Mary’s Hospital, The College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul 06591, Republic of Korea; (S.Y.C.); (Y.K.)
- Institute for Aging and Metabolic Disease, Seoul St. Mary’s Hospital, The College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul 06591, Republic of Korea
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5
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Cakir MU, Yavuz-Aksu B, Aksu U. Hypervolemia suppresses dilutional anaemic injury in a rat model of haemodilution. J Transl Int Med 2023; 11:393-400. [PMID: 38130643 PMCID: PMC10732576 DOI: 10.2478/jtim-2022-0045] [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: 11/16/2022] Open
Abstract
Background and Objectives Haemodilution leads to complications in clinical practice. It is exactly unknown whether this damage is caused by the fluid or by the stretching of the vascular bed. We aimed to compare two different haemodilution techniques at the same anaemic level. Methods Normovolemic or hypervolemic haemodilution was performed on twelve adult male Wistar rats. In the normovolemic procedure, blood was withdrawn and instantaneously administered with similar amounts of 6% hydroxyethyl starch (HES 130/0.4). Fluid was administered without withdrawing blood in the hypervolemic procedure. In both models, a 25% haematocrit level was targeted and kept at this level for 90 min to deepen the anaemia effect. Besides haemodynamics measurement, renal function (creatinine, blood urea nitrogen) and injury (tissue norepinephrine, malondialdehyde) were evaluated. Also, systemic hypoxia (lactate), oxidative stress (malondialdehyde, ischaemia-modified albumin), inflammation (tumour necrosis factor-alpha [TNF-α]), osmotic stress, adrenal stress (norepinephrine, epinephrine), and vascular stretching (atrial natriuretic peptide [ANP]) were assessed. Results Arterial pressure in the normovolemic group was lower than in the hypervolemic group. Serum creatinine, blood urea nitrogen, and lactate levels were higher in the normovolemic group. Tissue norepinephrine and malondialdehyde levels were higher in the normovolemic group. Serum ANP, malondialdehyde, ischaemia-modified albumin, free haemoglobin, syndecan-1, and TNF-α were higher in both groups compared to respective baseline. Conclusions Normovolemic haemodilution may lead to hypoxic kidney injury. The hypervolemic state may be advantageous if fluid is to be administered. Thus, the effect of the fluid itself can be relatively masked.
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Affiliation(s)
- Muzaffer Utku Cakir
- Department of Biology, Faculty of Science, University of Istanbul, Istanbul34134, Turkey
| | - Berna Yavuz-Aksu
- Duzen Laboratory Group, Biochemistry Section, Istanbul34394, Turkey
| | - Ugur Aksu
- Department of Biology, Faculty of Science, University of Istanbul, Istanbul34134, Turkey
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6
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Ergin B, van Rooij T, Lima A, Ince Y, Specht PA, Mik B, Aksu U, Yavuz-Aksu B, Kooiman K, de Jong N, Ince C. Intra-renal microcirculatory alterations on non-traumatic hemorrhagic shock induced acute kidney injury in pigs. J Clin Monit Comput 2023; 37:1193-1205. [PMID: 36745316 PMCID: PMC10520149 DOI: 10.1007/s10877-023-00978-7] [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: 11/14/2022] [Revised: 01/18/2023] [Accepted: 01/22/2023] [Indexed: 02/07/2023]
Abstract
Acute kidney injury (AKI) is frequently seen in patients with hemorrhagic shock due to hypotension, tissue hypoxia, and inflammation despite adequate resuscitation. There is a lack of information concerning the alteration of renal microcirculation and perfusion during shock and resuscitation. The aim of this study was to investigate the possible role of renal microcirculatory alterations on development of renal dysfunction in a pig model of non-traumatic hemorrhagic shock (HS) induced AKI.Fully instrumented female pigs were divided into the two groups as Control (n = 6) and HS (n = 11). HS was achieved by withdrawing blood until mean arterial pressure (MAP) reached around 50 mmHg. After an hour cessation period, fluid resuscitation with balanced crystalloid was started for the duration of 1 h. The systemic and renal hemodynamics, renal microcirculatory perfusion (contrast-enhanced ultrasound (CEUS)) and the sublingual microcirculation were measured.CEUS peak enhancement was significantly increased in HS during shock, early-, and late resuscitation indicating perfusion defects in the renal cortex (p < 0.05 vs. baseline, BL) despite a stable renal blood flow (RBF) and urine output. Following normalization of systemic hemodynamics, we observed persistent hypoxia (high lactate) and high red blood cell (RBC) velocity just after initiation of resuscitation resulting in further endothelial and renal damage as shown by increased plasma sialic acid (p < 0.05 vs. BL) and NGAL levels. We also showed that total vessel density (TVD) and functional capillary density (FCD) were depleted during resuscitation (p < 0.05).In this study, we showed that the correction of systemic hemodynamic variables may not be accompanied with the improvement of renal cortical perfusion, intra-renal blood volume and renal damage following fluid resuscitation. We suggest that the measurement of renal injury biomarkers, systemic and renal microcirculation can be used for guiding to the optimization of fluid therapies.
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Affiliation(s)
- Bülent Ergin
- Department of Adult Intensive Care, Erasmus MC, University Medical Center Rotterdam, Erasmus University, Doctor Molewaterplein 40, 3015 GD, Rotterdam, The Netherlands.
| | - Tom van Rooij
- Department of Biomedical Engineering, Thorax Center, Erasmus MC, Rotterdam, The Netherlands
| | - Alex Lima
- Department of Adult Intensive Care, Erasmus MC, University Medical Center Rotterdam, Erasmus University, Doctor Molewaterplein 40, 3015 GD, Rotterdam, The Netherlands
| | - Yasin Ince
- Department of Translational Physiology, Academic Medical Center, Amsterdam, The Netherlands
| | - Patricia Ac Specht
- Laboratory of Experimental Anesthesiology, Department of Anesthesiology, Erasmus MC, Rotterdam, The Netherlands
| | - Bert Mik
- Laboratory of Experimental Anesthesiology, Department of Anesthesiology, Erasmus MC, Rotterdam, The Netherlands
| | - Ugur Aksu
- Department of Biology, Zoology Division, University of Istanbul, Istanbul, Turkey
| | | | - Klazina Kooiman
- Department of Biomedical Engineering, Thorax Center, Erasmus MC, Rotterdam, The Netherlands
| | - Nico de Jong
- Department of Biomedical Engineering, Thorax Center, Erasmus MC, Rotterdam, The Netherlands
- Laboratory of Acoustical Wavefield Imaging, Department of Applied Sciences, Delft University of Technology, Delft, The Netherlands
| | - Can Ince
- Department of Adult Intensive Care, Erasmus MC, University Medical Center Rotterdam, Erasmus University, Doctor Molewaterplein 40, 3015 GD, Rotterdam, The Netherlands
- Department of Translational Physiology, Academic Medical Center, Amsterdam, The Netherlands
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7
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Rondinelli MB, Weltert LP, Ruocco G, Ornelli M, Delle Femmine PF, De Rosa A, Pierelli L, Felici N. Patient Blood Management in Microsurgical Procedures for Reconstructive Surgery. Diagnostics (Basel) 2023; 13:2758. [PMID: 37685296 PMCID: PMC10486619 DOI: 10.3390/diagnostics13172758] [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: 05/30/2023] [Revised: 07/24/2023] [Accepted: 08/09/2023] [Indexed: 09/10/2023] Open
Abstract
Introduction: The main purpose of reconstructive surgery (RS) is to restore the integrity of soft tissues damaged by trauma, surgery, congenital deformity, burns, or infection. Microsurgical techniques consist of harvesting tissues that are separated from the vascular sources of the donor site and anastomosed to the vessels of the recipient site. In these procedures, there are some preoperative modifiable factors that have the potential to influence the outcome of the flap transfer and its anastomosis. The management of anemia, which is always present in the postoperative period and plays a decisive role in the implantation of the flap, covers significant importance, and is associated with clinical and laboratory settings of chronic inflammation. Methods: Chronic inflammatory anemia (ACD) is a constant condition in patients who have undergone RS and correlates with the perfusion of the free flap. The aim of this treatment protocol is to reduce the transfusion rate by maintaining both a good organ perfusion and correction of the patient's anemic state. From January 2017 to September 2019, we studied 16 patients (16 males, mean age 38 years) who underwent microsurgical procedures for RS. Their hemoglobin (Hb) levels, corpuscular indexes, transferrin saturation (TSAT) ferritin concentrations and creatinine clearance were measured the first day after surgery (T0), after the first week (T1), and after five weeks (T2). At T0, all the patients showed low hemoglobin levels (average 7.4 g/dL, STD 0.71 range 6.2-7.4 g dL-1), with an MCV of 72, MCH of 28, MCHC of 33, RDW of 16, serum iron of 35, ferritin of 28, Ret% of 1.36, TRF of 277, creatinine clearance of 119 and high ferritin levels (range 320-560 ng mL-1) with TSAT less than 20%. All the patients were assessed for their clinical status, medical history and comorbidities before the beginning of the therapy. Results: A collaboration between the two departments (Department of Transfusion Medicine and Department of Reconstructive Surgery) resulted in the application of a therapeutic protocol with erythropoietic stimulating agents (ESAs) (Binocrit 6000 UI/week) and intravenous iron every other day, starting the second day after surgery. Thirteen patients received ESAs and FCM (ferric carboxymaltose, 500-1000 mg per session), three patients received ESAs and iron gluconate (one vial every other day). No patients received blood transfusions. No side effects were observed, and most importantly, no limb or flap rejection occurred. Conclusions: Preliminary data from our protocol show an optimal therapeutic response, notwithstanding the very limited scientific literature and data available in this specific surgical field. The enrollment of further patients will allow us to validate this therapeutic protocol with statistically sound data.
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Affiliation(s)
| | - Luca Paolo Weltert
- Department of Medical Statistics, Saint Camillus International University of Health and Medical Sciences (UniCamillus), 00131 Rome, Italy
| | - Giovanni Ruocco
- Department of Reconstructive Surgery, San Camillo-Forlanini Hospital, 00152 Rome, Italy (N.F.)
| | - Matteo Ornelli
- Department of Reconstructive Surgery, San Camillo-Forlanini Hospital, 00152 Rome, Italy (N.F.)
| | | | - Alessandro De Rosa
- Department of Transfusion Medicine, San Camillo-Forlanini Hospital, 00152 Rome, Italy (L.P.)
| | - Luca Pierelli
- Department of Transfusion Medicine, San Camillo-Forlanini Hospital, 00152 Rome, Italy (L.P.)
- Department of Experimental Medicine, La Sapienza University, 00161 Rome, Italy
| | - Nicola Felici
- Department of Reconstructive Surgery, San Camillo-Forlanini Hospital, 00152 Rome, Italy (N.F.)
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Chin K, Joo H, Jiang H, Lin C, Savinova I, Joo S, Alli A, Sklar MC, Papa F, Simpson J, Baker AJ, Mazer CD, Darrah W, Hare GMT. Importance of assessing biomarkers and physiological parameters of anemia-induced tissue hypoxia in the perioperative period. BRAZILIAN JOURNAL OF ANESTHESIOLOGY (ELSEVIER) 2023; 73:186-197. [PMID: 36377057 PMCID: PMC10068554 DOI: 10.1016/j.bjane.2022.10.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 10/14/2022] [Accepted: 10/17/2022] [Indexed: 11/06/2022]
Abstract
Anemia is associated with increased risk of Acute Kidney Injury (AKI), stroke and mortality in perioperative patients. We sought to understand the mechanism(s) by assessing the integrative physiological responses to anemia (kidney, brain), the degrees of anemia-induced tissue hypoxia, and associated biomarkers and physiological parameters. Experimental measurements demonstrate a linear relationship between blood Oxygen Content (CaO2) and renal microvascular PO2 (y = 0.30x + 6.9, r2 = 0.75), demonstrating that renal hypoxia is proportional to the degree of anemia. This defines the kidney as a potential oxygen sensor during anemia. Further evidence of renal oxygen sensing is demonstrated by proportional increase in serum Erythropoietin (EPO) during anemia (y = 93.806*10-0.02, r2 = 0.82). This data implicates systemic EPO levels as a biomarker of anemia-induced renal tissue hypoxia. By contrast, cerebral Oxygen Delivery (DO2) is defended by a profound proportional increase in Cerebral Blood Flow (CBF), minimizing tissue hypoxia in the brain, until more severe levels of anemia occur. We hypothesize that the kidney experiences profound early anemia-induced tissue hypoxia which contributes to adaptive mechanisms to preserve cerebral perfusion. At severe levels of anemia, renal hypoxia intensifies, and cerebral hypoxia occurs, possibly contributing to the mechanism(s) of AKI and stroke when adaptive mechanisms to preserve organ perfusion are overwhelmed. Clinical methods to detect renal tissue hypoxia (an early warning signal) and cerebral hypoxia (a later consequence of severe anemia) may inform clinical practice and support the assessment of clinical biomarkers (i.e., EPO) and physiological parameters (i.e., urinary PO2) of anemia-induced tissue hypoxia. This information may direct targeted treatment strategies to prevent adverse outcomes associated with anemia.
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Affiliation(s)
- Kyle Chin
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada; University of Toronto, Department of Physiology, Toronto, Canada
| | - Hannah Joo
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada
| | - Helen Jiang
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada
| | - Chloe Lin
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada
| | - Iryna Savinova
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Canada
| | - Sarah Joo
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada
| | - Ahmad Alli
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada
| | - Michael C Sklar
- St. Michael's Hospital, Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, Toronto, Canada; University of Toronto, Temerty Faculty of Medicine, Interdepartmental Division of Critical Care Medicine, Toronto, Canada; University of Toronto, St. Michael's Hospital, Department of Critical Care, Toronto, Canada
| | - Fabio Papa
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada
| | - Jeremy Simpson
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Canada
| | - Andrew J Baker
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada; St. Michael's Hospital, Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, Toronto, Canada; University of Toronto, Temerty Faculty of Medicine, Interdepartmental Division of Critical Care Medicine, Toronto, Canada; University of Toronto, St. Michael's Hospital, Department of Critical Care, Toronto, Canada
| | - C David Mazer
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada; University of Toronto, Department of Physiology, Toronto, Canada; St. Michael's Hospital, Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, Toronto, Canada; University of Toronto, Temerty Faculty of Medicine, Interdepartmental Division of Critical Care Medicine, Toronto, Canada; University of Toronto, St. Michael's Hospital, Department of Critical Care, Toronto, Canada
| | - William Darrah
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada
| | - Gregory M T Hare
- University of Toronto, Temerty Faculty of Medicine, St. Michael's Hospital, Department of Anesthesia and Pain Medicine, Toronto, Canada; University of Toronto, Department of Physiology, Toronto, Canada; St. Michael's Hospital, Keenan Research Centre for Biomedical Science in the Li Ka Shing Knowledge Institute, Toronto, Canada; St. Michael's Hospital Center of Excellence for Patient Blood Management, 30 Bond Street, Toronto, Canada.
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9
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Norepinephrine and Vasopressin in Hemorrhagic Shock: A Focus on Renal Hemodynamics. Int J Mol Sci 2023; 24:ijms24044103. [PMID: 36835514 PMCID: PMC9967703 DOI: 10.3390/ijms24044103] [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: 01/02/2023] [Revised: 02/01/2023] [Accepted: 02/15/2023] [Indexed: 02/22/2023] Open
Abstract
During hemorrhagic shock, blood loss causes a fall in blood pressure, decreases cardiac output, and, consequently, O2 transport. The current guidelines recommend the administration of vasopressors in addition to fluids to maintain arterial pressure when life-threatening hypotension occurs in order to prevent the risk of organ failure, especially acute kidney injury. However, different vasopressors exert variable effects on the kidney, depending on the nature and dose of the substance chosen as follows: Norepinephrine increases mean arterial pressure both via its α-1-mediated vasoconstriction leading to increased systemic vascular resistance and its β1-related increase in cardiac output. Vasopressin, through activation of V1-a receptors, induces vasoconstriction, thus increasing mean arterial pressure. In addition, these vasopressors have the following different effects on renal hemodynamics: Norepinephrine constricts both the afferent and efferent arterioles, whereas vasopressin exerts its vasoconstrictor properties mainly on the efferent arteriole. Therefore, this narrative review discusses the current knowledge of the renal hemodynamic effects of norepinephrine and vasopressin during hemorrhagic shock.
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10
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Yang L, Mo L, Li F, Zhu F, Bai Y. Application of ultrasound microbubble contrast to evaluate the effect of sitaxentan on renal microvascular perfusion in beagles undergoing cardiopulmonary bypass. Clin Hemorheol Microcirc 2023; 85:115-121. [PMID: 37599525 DOI: 10.3233/ch-221600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/22/2023]
Abstract
BACKGROUND & OBJECTIVE We aimed to evaluate the effect of sitaxentan on renal microvascular perfusion via application of ultrasound microbubble contrast. METHODS Male beagles were randomly divided into: Sham, cardiopulmonary bypass (CPB) and sitaxentan-infused (Sit) groups (n = 6). The ascending slope rate (ASR), area under the curve (AUC), derived peak intensity, and time to peak (TTP) were obtained via ultrasound microbubble contrast before CPB (T1), after 1 h CPB (T2), at end of CPB (T3), and 2 h after CPB (T4). RESULTS Compared with the Sham group, the CPB group had lower ASR of the renal cortex and medulla at T2 - 4, higher AUC and TTP at T3 - 4, and lower derived peak intensity at T4. The ASR at T2 - 4 in the Sit group was lower, TTP was higher at T2 - 4, and AUC was higher at T3 - 4 (P < 0.05). Compared with the CPB group, the Sit group had higher ASR of the renal cortex and medulla at T3 - 4 and AUC and TTP at T3 - 4 (P < 0.05). Compared with that at T1, the ASR of the renal cortex and medulla at T2 - 4 in the CPB group was lower, and AUC and TTP were higher at T3 - 4. The ASR of the renal cortex and medulla at T2 - 4 in the Sit group was lower, TTP was higher at T2 - 4, and AUC was higher at T4 (P < 0.05). CONCLUSIONS Ultrasound microbubble contrast could be effectively used to evaluate renal microvascular perfusion peri-CPB in beagles, which was prone to decrease and could be improved via pretreatment with sitaxentan.
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Affiliation(s)
- Lu Yang
- Department of Anesthesiology, Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Liqun Mo
- Department of Anesthesiology, Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Fuyu Li
- Department of Anesthesiology, Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Fuzu Zhu
- Department of Anesthesiology, Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Yiping Bai
- Department of Anesthesiology, Affiliated Hospital of Southwest Medical University, Luzhou, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Luzhou, China
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11
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Tomić Mahečić T, Brooks R, Noitz M, Sarmiento I, Baronica R, Meier J. The Limits of Acute Anemia. J Clin Med 2022; 11:jcm11185279. [PMID: 36142930 PMCID: PMC9505011 DOI: 10.3390/jcm11185279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 09/04/2022] [Accepted: 09/05/2022] [Indexed: 01/28/2023] Open
Abstract
For many years, physicians’ approach to the transfusion of allogeneic red blood cells (RBC) was not individualized. It was accepted that a hemoglobin concentration (Hb) of less than 10 g/dL was a general transfusion threshold and the majority of patients were transfused immediately. In recent years, there has been increasing evidence that even significantly lower hemoglobin concentrations can be survived in the short term without sequelae. This somehow contradicts the observation that moderate or mild anemia is associated with relevant long-term morbidity and mortality. To resolve this apparent contradiction, it must be recognized that we have to avoid acute anemia or treat it by alternative methods. The aim of this article is to describe the physiological limits of acute anemia, match these considerations with clinical realities, and then present “patient blood management” (PBM) as the therapeutic concept that can prevent both anemia and unnecessary transfusion of RBC concentrates in a clinical context, especially in Intensive Care Units (ICU). This treatment concept may prove to be the key to high-quality patient care in the ICU setting in the future.
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Affiliation(s)
- Tina Tomić Mahečić
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Center Zagreb—“Rebro”, 10000 Zagreb, Croatia
| | - Roxane Brooks
- Department of Anesthesiology and Critical Care Medicine, Kepler University Hospital GmbH, Johannes Kepler University, 4040 Linz, Austria
| | - Matthias Noitz
- Department of Anesthesiology and Critical Care Medicine, Kepler University Hospital GmbH, Johannes Kepler University, 4040 Linz, Austria
| | - Ignacio Sarmiento
- Department of Anesthesiology, Clinica Santa Maria, Santiago 7520378, Chile
| | - Robert Baronica
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Center Zagreb—“Rebro”, 10000 Zagreb, Croatia
| | - Jens Meier
- Department of Anesthesiology and Critical Care Medicine, Kepler University Hospital GmbH, Johannes Kepler University, 4040 Linz, Austria
- Correspondence:
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12
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Kidney Microcirculation as a Target for Innovative Therapies in AKI. J Clin Med 2021; 10:jcm10184041. [PMID: 34575154 PMCID: PMC8471583 DOI: 10.3390/jcm10184041] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 08/29/2021] [Accepted: 09/02/2021] [Indexed: 12/19/2022] Open
Abstract
Acute kidney injury (AKI) is a serious multifactorial conditions accompanied by the loss of function and damage. The renal microcirculation plays a crucial role in maintaining the kidney’s functional and structural integrity for oxygen and nutrient supply and waste product removal. However, alterations in microcirculation and oxygenation due to renal perfusion defects, hypoxia, renal tubular, and endothelial damage can result in AKI and the loss of renal function regardless of systemic hemodynamic changes. The unique structural organization of the renal microvasculature and the presence of autoregulation make it difficult to understand the mechanisms and the occurrence of AKI following disorders such as septic, hemorrhagic, or cardiogenic shock; ischemia/reperfusion; chronic heart failure; cardiorenal syndrome; and hemodilution. In this review, we describe the organization of microcirculation, autoregulation, and pathophysiological alterations leading to AKI. We then suggest innovative therapies focused on the protection of the renal microcirculation and oxygenation to prevent AKI.
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13
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Guven G, Ince C, Topeli A, Caliskan K. Cardio-Pulmonary-Renal Consequences of Severe COVID-19. Cardiorenal Med 2021; 11:133-139. [PMID: 34082420 PMCID: PMC8247817 DOI: 10.1159/000516740] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 04/16/2021] [Indexed: 01/08/2023] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 has rapidly spread worldwide and resulted in the coronavirus disease 2019 (COVID-19) pandemic. The disease raised an unprecedented demand for intensive care support due to severe pulmonary dysfunction and multiorgan failure. Although the pulmonary system is the potential target of the COVID-19, recent reports have demonstrated that COVID-19 profoundly influences the cardiovascular system and the kidneys. Research studies on cadavers have shown that direct heart and kidney injury can be frequently seen in patients deceased due to COVID-19 infection. On the other hand, functional or structural dysfunction of the heart may deteriorate the renal function and vice versa. This concept is already known as the cardiorenal syndrome and may play a role in COVID-19. Proactive monitoring of micro- and macrohemodynamics could allow prompt correction of circulatory dysfunction and can be of pivotal importance in the prevention of acute kidney injury. Moreover, type and amount of fluid therapy and vasoactive drug support could help manage these patients either with or without mechanical ventilator support. This brief review outlines the current evidence regarding the COVID-19-related renal and cardiorenal complications and discusses potential hemodynamic management strategies.
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Affiliation(s)
- Goksel Guven
- Department of Intensive Care Adults, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands, .,Department of Intensive Care Adults, Tokat State Hospital, Tokat, Turkey, .,Division of Intensive Care Medicine, Department of Internal Medicine, Hacettepe University Faculty of Medicine, Ankara, Turkey,
| | - Can Ince
- Department of Intensive Care Adults, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Arzu Topeli
- Division of Intensive Care Medicine, Department of Internal Medicine, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Kadir Caliskan
- Department of Cardiology, Unit Heart Failure, Heart Transplantation & Mechanical Circulatory Support, Thorax Center, Rotterdam, The Netherlands
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14
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Carcy R, Cougnon M, Poet M, Durandy M, Sicard A, Counillon L, Blondeau N, Hauet T, Tauc M, F Pisani D. Targeting oxidative stress, a crucial challenge in renal transplantation outcome. Free Radic Biol Med 2021; 169:258-270. [PMID: 33892115 DOI: 10.1016/j.freeradbiomed.2021.04.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 03/31/2021] [Accepted: 04/15/2021] [Indexed: 02/07/2023]
Abstract
Disorders characterized by ischemia/reperfusion (I/R) are the most common causes of debilitating diseases and death in stroke, cardiovascular ischemia, acute kidney injury or organ transplantation. In the latter example the I/R step defines both the amplitude of the damages to the graft and the functional recovery outcome. During transplantation the kidney is subjected to blood flow arrest followed by a sudden increase in oxygen supply at the time of reperfusion. This essential clinical protocol causes massive oxidative stress which is at the basis of cell death and tissue damage. The involvement of both reactive oxygen species (ROS) and nitric oxides (NO) has been shown to be a major cause of these cellular damages. In fact, in non-physiological situations, these species escape endogenous antioxidant control and dangerously accumulate in cells. In recent years, the objective has been to find clinical and pharmacological treatments to reduce or prevent the appearance of oxidative stress in ischemic pathologies. This is very relevant because, due to the increasing success of organ transplantation, clinicians are required to use limit organs, the preservation of which against oxidative stress is crucial for a better outcome. This review highlights the key actors in oxidative stress which could represent new pharmacological targets.
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Affiliation(s)
- Romain Carcy
- Université Côte d'Azur, CNRS, LP2M, Nice, France; CHU Nice, Hôpital Pasteur 2, Service de Réanimation Polyvalente et Service de Réanimation des Urgences Vitales, Nice, France; Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France
| | - Marc Cougnon
- Université Côte d'Azur, CNRS, LP2M, Nice, France; Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France
| | - Mallorie Poet
- Université Côte d'Azur, CNRS, LP2M, Nice, France; Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France
| | - Manon Durandy
- Université Côte d'Azur, CNRS, LP2M, Nice, France; Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France
| | - Antoine Sicard
- Université Côte d'Azur, CNRS, LP2M, Nice, France; Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France; CHU Nice, Hôpital Pasteur 2, Service de Néphrologie-Dialyse-Transplantation, Nice, France; Clinical Research Unit of Université Côte d'Azur (UMR2CA), France
| | - Laurent Counillon
- Université Côte d'Azur, CNRS, LP2M, Nice, France; Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France
| | | | - Thierry Hauet
- Université de Poitiers, INSERM, IRTOMIT, CHU de Poitiers, La Milétrie, Poitiers, France
| | - Michel Tauc
- Université Côte d'Azur, CNRS, LP2M, Nice, France; Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France
| | - Didier F Pisani
- Université Côte d'Azur, CNRS, LP2M, Nice, France; Laboratories of Excellence Ion Channel Science and Therapeutics, Nice, France.
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15
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MacIsaac S, Ramanakumar AV, Saw C, Naessens V, Saberi N, Cantarovich M, Baran D, Paraskevas S, Tchervenkov J, Chaudhury P, Sandal S. Relative decrease in hemoglobin and outcomes in patients undergoing kidney transplantation surgery: A retrospective cohort study. Am J Surg 2021; 222:825-831. [PMID: 33707078 DOI: 10.1016/j.amjsurg.2021.03.002] [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: 10/26/2020] [Revised: 02/09/2021] [Accepted: 03/01/2021] [Indexed: 11/29/2022]
Abstract
BACKGROUND Recent surgical literature suggests that a relative decrease in hemoglobin (ΔHb) is predictive of adverse outcomes regardless of the absolute level. We aimed to examine the association between perioperative ΔHb and kidney transplantation (KT) outcomes. METHODS This was a retrospective cohort study of transplant recipients, where ΔHb = [Hb0- Hb1Hb0]x 100 (Hb0 = hemoglobin pre-KT and Hb1 = lowest hemoglobin 24-h post-KT). The main outcome of interest was immediate graft function (IGF). RESULTS Of the 899 eligible patients, 38% experienced IGF, and ΔHb was associated with 36% lower odds of IGF. Also, ΔHb was associated with higher all-cause graft failure and longer length of stay but not death-censored graft failure or mortality. ΔHb ≥30% was the threshold beyond which the odds of IGF were significantly lower even if Hb1 was ≥7 g/dL. CONCLUSION ΔHb is associated with inferior outcomes independent of Hb1; whether it can be used to guide transfusion practices should be explored.
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Affiliation(s)
- Sarah MacIsaac
- Faculty of Medicine, McGill University, Montreal, Quebec, Canada.
| | | | - Chee Saw
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada; Division of Hematology, Department of Medicine, McGill University Health Centre, Montreal, Quebec, Canada.
| | - Veronique Naessens
- Division of Hematology, Department of Medicine, McGill University Health Centre, Montreal, Quebec, Canada.
| | - Nasim Saberi
- Department of Surgery, McGill University Health Centre, Montreal, Quebec, Canada.
| | - Marcelo Cantarovich
- Division of Nephrology, Department of Medicine, McGill University Health Centre, Montreal, Quebec, Canada.
| | - Dana Baran
- Division of Nephrology, Department of Medicine, McGill University Health Centre, Montreal, Quebec, Canada.
| | - Steven Paraskevas
- Department of Surgery, McGill University Health Centre, Montreal, Quebec, Canada.
| | - Jean Tchervenkov
- Department of Surgery, McGill University Health Centre, Montreal, Quebec, Canada.
| | - Prosanto Chaudhury
- Department of Surgery, McGill University Health Centre, Montreal, Quebec, Canada.
| | - Shaifali Sandal
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada; Division of Nephrology, Department of Medicine, McGill University Health Centre, Montreal, Quebec, Canada.
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16
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Chen Y, Yu T. Mouse liver is more resistant than skeletal muscle to heat-induced apoptosis. Cell Stress Chaperones 2021; 26:275-281. [PMID: 32880059 PMCID: PMC7736438 DOI: 10.1007/s12192-020-01163-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 08/05/2020] [Accepted: 08/27/2020] [Indexed: 01/28/2023] Open
Abstract
During passive heat stress, shifting of blood flow from the hepato-splanchnic to peripheral regions produces less favorable physiological conditions in the liver than in the skeletal muscle. We were wondering if the two organs differ in susceptibility to heat injury and thus examined the effects of heat shock exposure on apoptotic and heat stress-related markers in the gastrocnemius muscle and liver of mice. During heat exposure, mice had a peak core body temperature of 41.1 ± 0.7 °C. Heat-exposed mice showed higher levels of reactive oxygen species (ROS), cleaved caspases, fragmented DNA, and Drp1 protein expression in the gastrocnemius muscles than control mice. These changes were not observed in the livers of heat-exposed mice. Furthermore, the levels of glucocorticoid receptor, HSP70, and HSF1 proteins were significantly elevated in the gastrocnemius muscles of heat-exposed mice compared with that of control mice. The livers of heat-exposed mice also revealed increased expression of HSP70 but no changes in the other proteins. These results demonstrate that heat exposure induces significantly lower levels of the stress response and apoptosis in the liver than in the skeletal muscle of mice. The liver tissue resistance against heat stress is associated with low levels of heat-induced ROS production and mitochondrial fission protein expression.
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Affiliation(s)
- Yifan Chen
- Department of Military and Emergency Medicine, Hébert School of Medicine, Uniformed Services University, 4301 Jones Bridge Road, Bethesda, MD, 20814, USA.
| | - Tianzheng Yu
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
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17
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Tomic Mahecic T, Dünser M, Meier J. RBC Transfusion Triggers: Is There Anything New? Transfus Med Hemother 2020; 47:361-368. [PMID: 33173454 PMCID: PMC7590774 DOI: 10.1159/000511229] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 08/31/2020] [Indexed: 01/28/2023] Open
Abstract
For many years, in daily clinical practice, the traditional 10/30 rule (hemoglobin 10 g/dL - hematocrit 30%) has been the most commonly used trigger for blood transfusions. Over the years, this approach is believed to have contributed to a countless number of unnecessary transfusions and an unknown number of overtransfusion-related deaths. Recent studies have shown that lower hemoglobin levels can safely be accepted, even in critically ill patients. However, even these new transfusion thresholds are far beyond the theoretical limits of individual anemia tolerance. For this reason, almost all publications addressing the limits of acute anemia recommend physiological transfusion triggers to indicate the transfusion of erythrocyte concentrates as an alternative. Although this concept appears intuitive at first glance, no solid scientific evidence supports the safety and benefit of physiological transfusion triggers to indicate the optimal time point for transfusion of allogeneic blood. It is therefore imperative to continue searching for the most sensitive and specific parameters that can guide the clinician when to transfuse in order to avoid anemia-induced organ dysfunction while avoiding overtransfusion-related adverse effects. This narrative review discusses the concept of anemia tolerance and critically compares hemoglobin-based triggers with physiological transfusion for various clinical indications.
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Affiliation(s)
- Tina Tomic Mahecic
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Center Zagreb − Rebro, Zagreb, Croatia
| | - Martin Dünser
- Department of Anesthesiology and Intensive Care Medicine, Johannes Kepler University, Linz, Austria
| | - Jens Meier
- Department of Anesthesiology and Intensive Care Medicine, Johannes Kepler University, Linz, Austria
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18
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Sato T, Mimuro S, Katoh T, Kurita T, Truong SK, Kobayashi K, Makino H, Doi M, Nakajima Y. 1.2% Hydrogen gas inhalation protects the endothelial glycocalyx during hemorrhagic shock: a prospective laboratory study in rats. J Anesth 2020; 34:268-275. [PMID: 31997005 DOI: 10.1007/s00540-020-02737-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 01/13/2020] [Indexed: 01/07/2023]
Abstract
PURPOSE Hydrogen gas (H2) inhalation improved the survival rate of hemorrhagic shock. However, its mechanisms are unknown. We hypothesized that H2 protected the endothelial glycocalyx during hemorrhagic shock and prolonged survival time. METHODS 83 Sprague-Dawley rats were anesthetized with isoflurane. The animals were randomly assigned to 5 groups: room air with no shock, 1.2% H2 with no shock, room air with shock (Control-S), 1.2% H2 with shock (H21.2%-S), and 3.0% H2 with shock (H23.0%-S). Shock groups were bled to a mean arterial pressure of 30-35 mmHg and held for 60 min, then resuscitated with normal saline at fourfold the amount of the shed blood volume. RESULTS The syndecan-1 level was significantly lower in the H21.2%-S [8.3 ± 6.6 ng/ml; P = 0.01; 95% confidence interval (CI), 3.2-35.8] than in the Control-S (27.9 ± 17.0 ng/ml). The endothelial glycocalyx was significantly thicker in the H21.2%-S (0.15 ± 0.02 µm; P = 0.007; 95% CI, 0.02-0.2) than in the Control-S (0.06 ± 0.02 µm). The survival time was longer in the H21.2%-S (327 ± 67 min, P = 0.0160) than in the Control-S (246 ± 69 min). The hemoglobin level was significantly lower in the H21.2%-S (9.4 ± 0.5 g/dl; P = 0.0034; 95% CI, 0.6-2.9) than in the Control-S (11.1 ± 0.8 g/dl). However, the H23.0%-S was not significant. CONCLUSIONS Inhalation of 1.2% H2 gas protected the endothelial glycocalyx and prolonged survival time during hemorrhagic shock. Therapeutic efficacy might vary depending on the concentration.
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Affiliation(s)
- Tsunehisa Sato
- Department of Anesthesiology and Intensive Care, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, 431-3192, Japan
| | - Soichiro Mimuro
- Department of Anesthesiology and Intensive Care, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, 431-3192, Japan.
| | - Takasumi Katoh
- Department of Anesthesiology and Intensive Care, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, 431-3192, Japan
| | - Tadayoshi Kurita
- Department of Anesthesiology and Intensive Care, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, 431-3192, Japan
| | - Sang Kien Truong
- Department of Anesthesiology and Intensive Care, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, 431-3192, Japan
| | - Kensuke Kobayashi
- Department of Anesthesiology and Intensive Care, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, 431-3192, Japan
| | - Hiroshi Makino
- Department of Anesthesiology and Intensive Care, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, 431-3192, Japan
| | - Matsuyuki Doi
- Department of Anesthesiology and Intensive Care, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, 431-3192, Japan
| | - Yoshiki Nakajima
- Department of Anesthesiology and Intensive Care, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, 431-3192, Japan
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Honda T, Hirakawa Y, Nangaku M. The role of oxidative stress and hypoxia in renal disease. Kidney Res Clin Pract 2019; 38:414-426. [PMID: 31558011 PMCID: PMC6913586 DOI: 10.23876/j.krcp.19.063] [Citation(s) in RCA: 94] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 07/16/2019] [Accepted: 07/22/2019] [Indexed: 12/12/2022] Open
Abstract
Oxygen is required to sustain aerobic organisms. Reactive oxygen species (ROS) are constantly released during mitochondrial oxygen consumption for energy production. Any imbalance between ROS production and its scavenger system induces oxidative stress. Oxidative stress, a critical contributor to tissue damage, is well-known to be associated with various diseases. The kidney is susceptible to hypoxia, and renal hypoxia is a common final pathway to end stage kidney disease, regardless of the underlying cause. Renal hypoxia aggravates oxidative stress, and elevated oxidative stress, in turn, exacerbates renal hypoxia. Oxidative stress is also enhanced in chronic kidney disease, especially diabetic kidney disease, through various mechanisms. Thus, the vicious cycle between oxidative stress and renal hypoxia critically contributes to the progression of renal injury. This review examines recent evidence connecting chronic hypoxia and oxidative stress in renal disease and subsequently describes several promising therapeutic approaches against oxidative stress.
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Affiliation(s)
- Tomoko Honda
- Division of Nephrology and Endocrinology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yosuke Hirakawa
- Division of Nephrology and Endocrinology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Masaomi Nangaku
- Division of Nephrology and Endocrinology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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20
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Mueller F, Teloh-Benger JK, Hussmann B, Lendemans S, Waack IN. Malate Protects the Kidneys From Hemorrhagic Shock-Induced Injury in an Experimental Rat Model. J Surg Res 2019; 245:225-233. [PMID: 31421367 DOI: 10.1016/j.jss.2019.07.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 04/30/2019] [Accepted: 07/11/2019] [Indexed: 01/11/2023]
Abstract
BACKGROUND In the past, protective effects in terms of prolonged survival of malate-containing solutions were demonstrated in the treatment of experimental hemorrhagic shock (HS). The objective of the present study was to investigate malate's impact on the kidneys. Therefore, renal function and morphological and histological anomalies were examined. MATERIALS AND METHODS Male Wistar rats were subjected to severe HS by dropping the mean arterial blood pressure to 25-30 mmHg. The depth was held for 60 min. Subsequently, reperfusion with Ringer's solution or a 10 mM malate-containing solution was performed both together with blood in a 2:1 relation, followed by an observation period of 150 min. RESULTS Compared with the control group (Ringer's solution), malate increased diuresis and, thus, enhanced excretion of creatinine and urea. Shock-induced histopathological changes were reduced by malate administration. Renal hemorrhages in the straight proximal tubule and in the distal tubule were reduced and even significantly reduced in the proximal convoluted tubule. Malate significantly preserved the endothelial glycocalyx in the proximal tubule. Surprisingly, malate induced glucosuria in the absence of a significant renal dysfunction, morphological damage, or hyperglycemia. CONCLUSIONS The protective effect of malate observed in the treatment of severe HS in the rat may be explained by a certain protective effect of this substance for the kidney.
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Affiliation(s)
- Friederike Mueller
- Institute of Physiological Chemistry, University of Duisburg-Essen, University Hospital Essen, Essen, Germany
| | | | - Bjoern Hussmann
- Department of Special Trauma Surgery, Alfried Krupp Hospital Essen-Ruettenscheid, Essen, Germany
| | - Sven Lendemans
- Department of Special Trauma Surgery, Alfried Krupp Hospital Essen-Ruettenscheid, Essen, Germany; Department of Trauma and Orthopedic Surgery, Alfried Krupp Hospital Essen-Steele, Essen, Germany
| | - Indra Naemi Waack
- Institute of Physiological Chemistry, University of Duisburg-Essen, University Hospital Essen, Essen, Germany.
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21
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Abstract
Colloid solutions have been advocated for use in treating hypovolemia due to their expected effect on improving intravascular retention compared with crystalloid solutions. Because the ultimate desired effect of fluid resuscitation is the improvement of microcirculatory perfusion and tissue oxygenation, it is of interest to study the effects of colloids and crystalloids at the level of microcirculation under conditions of shock and fluid resuscitation, and to explore the potential benefits of using colloids in terms of recruiting the microcirculation under conditions of hypovolemia. This article reviews the physiochemical properties of the various types of colloid solutions (eg, gelatin, dextrans, hydroxyethyl starches, and albumin) and the effects that they have under various conditions of hypovolemia in experimental and clinical scenarios.
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Affiliation(s)
- Huaiwu He
- From the Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing, China
| | - Dawei Liu
- From the Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing, China
| | - Can Ince
- Department of Translational Physiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.,Department of Intensive Care, Erasmus MC, University Hospital Rotterdam, Rotterdam, the Netherlands
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22
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Domizi R, Damiani E, Scorcella C, Carsetti A, Castagnani R, Vannicola S, Bolognini S, Gabbanelli V, Pantanetti S, Donati A. Association between sublingual microcirculation, tissue perfusion and organ failure in major trauma: A subgroup analysis of a prospective observational study. PLoS One 2019; 14:e0213085. [PMID: 30835764 PMCID: PMC6400441 DOI: 10.1371/journal.pone.0213085] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Accepted: 02/14/2019] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION Previous studies described impaired microvascular perfusion and tissue oxygenation as reliable predictors of Multiple Organ Failure in major trauma. However, this relationship has been incompletely investigated. The objective of this analysis is to further evaluate the association between organ dysfunction and microcirculation after trauma. MATERIALS AND METHODS This is a retrospective subgroup analysis on 28 trauma patients enrolled for the Microcirculation DAIly MONitoring in critically ill patients study (NCT 02649088). Patients were divided in two groups according with their Sequential Organ Failure Assessment (SOFA) score at day 4. At admission and every 24 hours, the sublingual microcirculation was evaluated with Sidestream Darkfield Imaging (SDF) and peripheral tissue perfusion was assessed with Near Infrared Spectroscopy (NIRS) and Vascular Occlusion Test (VOT). Simultaneously, hemodynamic, clinical/laboratory parameters and main organ supports were collected. RESULTS Median SOFA score at Day 4 was 6.5. Accordingly, patients were divided in two groups: D4-SOFA ≤6.5 and D4-SOFA >6.5. The Length of Stay in Intensive Care was significantly higher in patients with D4-SOFA>6.5 compared to D4-SOFA≤6.5 (p = 0.013). Total Vessel Density of small vessels was significantly lower in patients with high D4-SOFA score at Day 1 (p = 0.002) and Day 2 (p = 0.006) after admission; the Perfused Vessel Density was lower in patients with high D4-SOFA score at Day 1 (p = 0.007) and Day 2 (p = 0.033). At Day 1, NIRS monitoring with VOT showed significantly faster tissue oxygen saturation downslope (p = 0.018) and slower upslope (p = 0.04) in patients with high D4-SOFA. DISCUSSION In our cohort of major traumas, sublingual microcirculation and peripheral microvascular reactivity were significantly more impaired early after trauma in those patients who developed more severe organ dysfunctions. Our data would support the hypothesis that restoration of macrocirculation can be dissociated from restoration of peripheral and tissue perfusion, and that microvascular alterations can be associated with organ failure.
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Affiliation(s)
- Roberta Domizi
- Anaesthesia and Intensive Care, Department of Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona, Italy
| | - Elisa Damiani
- Anaesthesia and Intensive Care, Department of Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona, Italy
| | - Claudia Scorcella
- Anaesthesia and Intensive Care, Department of Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona, Italy
| | - Andrea Carsetti
- Anaesthesia and Intensive Care, Department of Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona, Italy
| | - Roberta Castagnani
- Anaesthesia and Intensive Care, Department of Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona, Italy
| | - Sara Vannicola
- Anaesthesia and Intensive Care, Department of Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona, Italy
| | - Sandra Bolognini
- Anaesthesia and Intensive Care, Department of Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona, Italy
| | - Vincenzo Gabbanelli
- Anaesthesia and Intensive Care, Department of Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona, Italy
| | - Simona Pantanetti
- Anaesthesia and Intensive Care, Department of Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona, Italy
| | - Abele Donati
- Anaesthesia and Intensive Care, Department of Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona, Italy
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23
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Waack IN, Petersen M, Verhaegh R, Teloh JK. The Liver and Small Intestine Can Partly Compensate Severe Normovolemic Hemodilution in a Rat Model. J Surg Res 2018; 232:605-613. [PMID: 30463780 DOI: 10.1016/j.jss.2018.07.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 06/23/2018] [Accepted: 07/10/2018] [Indexed: 12/23/2022]
Abstract
BACKGROUND Knowing the individual critical hematocrit for every organ is essential in operative scenarios in which extensive blood losses are expected. In the past, experimental settings were very heterogeneous resulting in the publication of widely differing values even for one organ in the same species. This study aimed to investigate the compensatory capacity of the liver and the small intestine in a rat model of severe normovolemic hemodilution. MATERIALS AND METHODS Male rats were subjected to a stepwise hemodilution with a succinylated gelatin-containing solution to a final hematocrit of 10%, being observed for additional 150 min. During the course of the experiment, blood glucose and L-lactate, as well as D-lactate and intestinal fatty acid-binding protein-2 measurements, were performed eight times in total. The amino acids alanine and glutamine were measured during dilution and at the end of the experiment (four times in total). Hemodilutional effects on the blood and oxygen supply of the liver and the small intestine were measured in a minimally invasive manner. RESULTS In the liver and the small intestine, there were no substantial changes in the blood flow of the microcirculation. Plasma glucose and lactate levels rose transiently, whereas lactate values did not exceed the upper threshold of aerobic metabolism. Plasma levels of the amino acids alanine and glutamine rose significantly and stayed elevated, whereas D-lactate and intestinal fatty acid-binding protein-2 were not significantly increased at any point during the whole experimental time compared to the initial value. CONCLUSIONS Severe hemodilution with a succinylated gelatin-containing solution is tolerated at a profoundly low hematocrit value of 10% during the experimental phase of 150 min.
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Affiliation(s)
- Indra Naemi Waack
- University of Duisburg-Essen, Institute of Physiological Chemistry, University Hospital Essen, Essen, Germany.
| | - Miriam Petersen
- Ambulatory Healthcare Center Dr. Eberhard & Partner Dortmund, Dortmund, Germany
| | - Rabea Verhaegh
- University of Duisburg-Essen, Institute of Physiological Chemistry, University Hospital Essen, Essen, Germany
| | - Johanna Katharina Teloh
- University of Duisburg-Essen, Institute of Physiological Chemistry, University Hospital Essen, Essen, Germany
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24
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Ranucci M, Johnson I, Willcox T, Baker RA, Boer C, Baumann A, Justison GA, de Somer F, Exton P, Agarwal S, Parke R, Newland RF, Haumann RG, Buchwald D, Weitzel N, Venkateswaran R, Ambrogi F, Pistuddi V. Goal-directed perfusion to reduce acute kidney injury: A randomized trial. J Thorac Cardiovasc Surg 2018; 156:1918-1927.e2. [DOI: 10.1016/j.jtcvs.2018.04.045] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 04/04/2018] [Accepted: 04/07/2018] [Indexed: 11/17/2022]
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25
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Mistry N, Mazer CD, Sled JG, Lazarus AH, Cahill LS, Solish M, Zhou YQ, Romanova N, Hare AGM, Doctor A, Fisher JA, Brunt KR, Simpson JA, Hare GMT. Red blood cell antibody-induced anemia causes differential degrees of tissue hypoxia in kidney and brain. Am J Physiol Regul Integr Comp Physiol 2018; 314:R611-R622. [PMID: 29351418 DOI: 10.1152/ajpregu.00182.2017] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Moderate anemia is associated with increased mortality and morbidity, including acute kidney injury (AKI), in surgical patients. A red blood cell (RBC)-specific antibody model was utilized to determine whether moderate subacute anemia could result in tissue hypoxia as a potential mechanism of injury. Cardiovascular and hypoxic cellular responses were measured in transgenic mice capable of expressing hypoxia-inducible factor-1α (HIF-1α)/luciferase activity in vivo. Antibody-mediated anemia was associated with mild intravascular hemolysis (6 h) and splenic RBC sequestration ( day 4), resulting in a nadir hemoglobin concentration of 89 ± 13 g/l on day 4. At this time point, renal tissue oxygen tension (PtO2) was decreased in anemic mice relative to controls (13.1 ± 4.3 vs. 20.8 ± 3.7 mmHg, P < 0.001). Renal tissue hypoxia was associated with an increase in HIF/luciferase expression in vivo ( P = 0.04) and a 20-fold relative increase in renal erythropoietin mRNA transcription ( P < 0.001) but no increase in renal blood flow ( P = 0.67). By contrast, brain PtO2 was maintained in anemic mice relative to controls (22.7 ± 5.2 vs. 23.4 ± 9.8 mmHg, P = 0.59) in part because of an increase in internal carotid artery blood flow (80%, P < 0.001) and preserved cerebrovascular reactivity. Despite these adaptive changes, an increase in brain HIF-dependent mRNA levels was observed (erythropoietin: P < 0.001; heme oxygenase-1: P = 0.01), providing evidence for subtle cerebral tissue hypoxia in anemic mice. These data demonstrate that moderate subacute anemia causes significant renal tissue hypoxia, whereas adaptive cerebrovascular responses limit the degree of cerebral tissue hypoxia. Further studies are required to assess whether hypoxia is a mechanism for acute kidney injury associated with anemia.
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Affiliation(s)
- Nikhil Mistry
- Department of Anesthesia, St. Michael's Hospital, University of Toronto , Toronto, Ontario , Canada.,Department of Physiology, University of Toronto , Toronto, Ontario , Canada
| | - C David Mazer
- Department of Anesthesia, St. Michael's Hospital, University of Toronto , Toronto, Ontario , Canada.,Department of Physiology, University of Toronto , Toronto, Ontario , Canada.,Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute, St. Michael's Hospital , Toronto, Ontario , Canada
| | - John G Sled
- Mouse Imaging Centre, The Hospital for Sick Children , Toronto, Ontario , Canada.,Department of Medical Biophysics, University of Toronto , Toronto, Ontario , Canada
| | - Alan H Lazarus
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute, St. Michael's Hospital , Toronto, Ontario , Canada.,Canadian Blood Services Centre for Innovation , Ottawa, Ontario , Canada
| | - Lindsay S Cahill
- Mouse Imaging Centre, The Hospital for Sick Children , Toronto, Ontario , Canada
| | - Max Solish
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute, St. Michael's Hospital , Toronto, Ontario , Canada
| | - Yu-Qing Zhou
- Mouse Imaging Centre, The Hospital for Sick Children , Toronto, Ontario , Canada
| | - Nadya Romanova
- Department of Human Health and Nutritional Sciences and Cardiovascular Research Group, University of Guelph , Guelph, Ontario , Canada
| | - Alexander G M Hare
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute, St. Michael's Hospital , Toronto, Ontario , Canada
| | - Allan Doctor
- Department of Pediatrics, Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis , St. Louis, Missouri
| | - Joseph A Fisher
- Department of Physiology, University of Toronto , Toronto, Ontario , Canada.,Department of Anesthesia, Toronto General Hospital, University of Toronto , Toronto, Ontario , Canada
| | - Keith R Brunt
- Department of Pharmacology, Dalhousie University , Saint John, New Brunswick , Canada
| | - Jeremy A Simpson
- Department of Human Health and Nutritional Sciences and Cardiovascular Research Group, University of Guelph , Guelph, Ontario , Canada
| | - Gregory M T Hare
- Department of Anesthesia, St. Michael's Hospital, University of Toronto , Toronto, Ontario , Canada.,Department of Physiology, University of Toronto , Toronto, Ontario , Canada.,Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute, St. Michael's Hospital , Toronto, Ontario , Canada.,St. Michael's Hospital Center of Excellence in Patient Blood Management, University of Toronto, Toronto, Ontario, Canada
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A Randomized Clinical Trial of Red Blood Cell Transfusion Triggers in Cardiac Surgery. Ann Thorac Surg 2017; 104:1243-1250. [DOI: 10.1016/j.athoracsur.2017.05.048] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 04/19/2017] [Accepted: 05/15/2017] [Indexed: 11/23/2022]
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27
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Hirakawa Y, Tanaka T, Nangaku M. Mechanisms of metabolic memory and renal hypoxia as a therapeutic target in diabetic kidney disease. J Diabetes Investig 2017; 8:261-271. [PMID: 28097824 PMCID: PMC5415475 DOI: 10.1111/jdi.12624] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 01/11/2017] [Accepted: 01/12/2017] [Indexed: 12/11/2022] Open
Abstract
Diabetic kidney disease (DKD) is a worldwide public health problem. The definition of DKD is under discussion. Although the term DKD was originally defined as ‘kidney disease specific to diabetes,’ DKD frequently means chronic kidney disease with diabetes mellitus and includes not only classical diabetic nephropathy, but also kidney dysfunction as a result of nephrosclerosis and other causes. Metabolic memory plays a crucial role in the progression of various complications of diabetes, including DKD. The mechanisms of metabolic memory in DKD are supposed to include advanced glycation end‐products, deoxyribonucleic acid methylation, histone modifications and non‐coding ribonucleic acid including micro ribonucleic acid. Regardless of the presence of diabetes mellitus, the final common pathway in chronic kidney disease is chronic kidney hypoxia, which influences epigenetic processes, including deoxyribonucleic acid methylation, histone modification, and conformational changes in micro ribonucleic acid and chromatin. Therefore, hypoxia and oxidative stress are appropriate targets of therapies against DKD. Prolyl hydroxylase domain inhibitor enhances the defensive mechanisms against hypoxia. Bardoxolone methyl protects against oxidative stress, and can even reverse impaired renal function; a phase 2 trial with considerable attention to heart complications is currently ongoing in Japan.
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Affiliation(s)
- Yosuke Hirakawa
- Division of Nephrology and Endocrinology, the University of Tokyo School of Medicine, Tokyo, Japan
| | - Tetsuhiro Tanaka
- Division of Nephrology and Endocrinology, the University of Tokyo School of Medicine, Tokyo, Japan
| | - Masaomi Nangaku
- Division of Nephrology and Endocrinology, the University of Tokyo School of Medicine, Tokyo, Japan
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28
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Experimental assessment of oxygen homeostasis during acute hemodilution: the integrated role of hemoglobin concentration and blood pressure. Intensive Care Med Exp 2017; 5:12. [PMID: 28251580 PMCID: PMC5332316 DOI: 10.1186/s40635-017-0125-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 02/21/2017] [Indexed: 11/12/2022] Open
Abstract
Background Low hemoglobin concentration (Hb) and low mean arterial blood pressure (MAP) impact outcomes in critically ill patients. We utilized an experimental model of “normotensive” vs. “hypotensive” acute hemodilutional anemia to test whether optimal tissue perfusion is dependent on both Hb and MAP during acute blood loss and fluid resuscitation, and to assess the value of direct measurements of the partial pressure of oxygen in tissue (PtO2). Methods Twenty-nine anesthetized rats underwent 40% isovolemic hemodilution (1:1) (or sham-hemodilution control, n = 4) with either hydroxyethyl starch (HES) (n = 14, normotensive anemia) or saline (n = 11, hypotensive anemia) to reach a target Hb value near 70 g/L. The partial pressure of oxygen in the brain and skeletal muscle tissue (PtO2) were measured by phosphorescence quenching of oxygen using G4 Oxyphor. Mean arterial pressure (MAP), heart rate, temperature, arterial and venous co-oximetry, blood gases, and lactate were assessed at baseline and for 60 min after hemodilution. Cardiac output (CO) was measured at baseline and immediately after hemodilution. Data were analyzed by repeated measures two-way ANOVA. Results Following “normotensive” hemodilution with HES, Hb was reduced to 66 ± 6 g/L, CO increased (p < 0.05), and MAP was maintained. These conditions resulted in a reduction in brain PtO2 (22.1 ± 5.6 mmHg to 17.5 ± 4.4 mmHg, p < 0.05), unchanged muscle PO2, and an increase in venous oxygen extraction. Following “hypotensive” hemodilution with saline, Hb was reduced to 79 ± 5 g/L and both CO and MAP were decreased (P < 0.05). These conditions resulted in a more severe reduction in brain PtO2 (23.2 ± 8.2 to 10.7 ± 3.6 mmHg (p < 0.05), a reduction in muscle PtO2 (44.5 ± 11.0 to 19.9 ± 12.4 mmHg, p < 0.05), a further increase in venous oxygen extraction, and a threefold increase in systemic lactate levels (p < 0.05). Conclusions Acute normotensive anemia (HES hemodilution) was associated with a subtle decrease in brain tissue PtO2 without clear evidence of global tissue hypoperfusion. By contrast, acute hypotensive anemia (saline hemodilution) resulted in a profound decrease in both brain and muscle tissue PtO2 and evidence of inadequate global perfusion (lactic acidosis). These data emphasize the importance of maintaining CO and MAP to ensure adequacy of vital organ oxygen delivery during acute anemia. Improved methods of assessing PtO2 may provide an earlier warning signal of vital organ hypoperfusion.
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29
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Al Drees A, Salah Khalil M, Soliman M. Histological and Immunohistochemical Basis of the Effect of Aminoguanidine on Renal Changes Associated with Hemorrhagic Shock in a Rat Model. Acta Histochem Cytochem 2017; 50:11-19. [PMID: 28386146 PMCID: PMC5374099 DOI: 10.1267/ahc.16025] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 12/01/2016] [Indexed: 12/26/2022] Open
Abstract
Acute kidney failure is the main cause of death among patients with severe trauma due to massive blood loss and hemorrhagic shock (HS). Renal cell injury is caused by tissue ischemia. Renal ischemia initiates a complex and interconnected chain of events resulting in cell injury and renal cell necrosis. Nitric oxide plays a crucial role in renal function and can be inhibited by aminoguanidine (AG). We studied whether AG can ameliorate pathological renal changes associated with HS syndrome in a rat model and explored the AG protection mechanism. Rats were intraperitoneally injected with heparin sodium and mean arterial blood pressure was monitored. Animals were divided into three groups: control (without hemorrhage), with or without intra-arterially injected AG; HS (blood continuously withdrawn or reinfused to maintain an MABP of 35-40 mmHg); and HS with AG. We found that AG decreased plasma concentrations of urea, creatinine, and nitrates; ameliorated histological changes of HS-induced rats; and decreased the expressions of inducible nitrogen oxide synthase (iNOS), proapoptotic protein (BAX), and vitamin D receptors (VDR). AG ameliorated kidney injury by inhibiting iNOS resulting in decreased BAX and VDR expressions. Therefore, a therapeutic strategy targeting AG may provide new insights into kidney injury during severe shock.
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Affiliation(s)
- Abdulmajeed Al Drees
- Department of Physiology/Department of Medical Education, College of Medicine, King Saud University
| | - Mahmoud Salah Khalil
- College of Medicine, King Saud University
- Department of Histology, Faculty of Medicine, Suez Canal University
| | - Mona Soliman
- Department of Physiology/Department of Medical Education, College of Medicine, King Saud University
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30
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Zafrani L, Ergin B, Kapucu A, Ince C. Blood transfusion improves renal oxygenation and renal function in sepsis-induced acute kidney injury in rats. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2016; 20:406. [PMID: 27993148 PMCID: PMC5168817 DOI: 10.1186/s13054-016-1581-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Accepted: 11/25/2016] [Indexed: 11/29/2022]
Abstract
Background The effects of blood transfusion on renal microcirculation during sepsis are unknown. This study aimed to investigate the effect of blood transfusion on renal microvascular oxygenation and renal function during sepsis-induced acute kidney injury. Methods Twenty-seven Wistar albino rats were randomized into four groups: a sham group (n = 6), a lipopolysaccharide (LPS) group (n = 7), a LPS group that received fluid resuscitation (n = 7), and a LPS group that received blood transfusion (n = 7). The mean arterial blood pressure, renal blood flow, and renal microvascular oxygenation within the kidney cortex were recorded. Acute kidney injury was assessed using the serum creatinine levels, metabolic cost, and histopathological lesions. Nitrosative stress (expression of endothelial (eNOS) and inducible nitric oxide synthase (iNOS)) within the kidney was assessed by immunohistochemistry. Hemoglobin levels, pH, serum lactate levels, and liver enzymes were measured. Results Fluid resuscitation and blood transfusion both significantly improved the mean arterial pressure and renal blood flow after LPS infusion. Renal microvascular oxygenation, serum creatinine levels, and tubular damage significantly improved in the LPS group that received blood transfusion compared to the group that received fluids. Moreover, the renal expression of eNOS was markedly suppressed under endotoxin challenge. Blood transfusion, but not fluid resuscitation, was able to restore the renal expression of eNOS. However, there were no significant differences in lactic acidosis or liver function between the two groups. Conclusions Blood transfusion significantly improved renal function in endotoxemic rats. The specific beneficial effect of blood transfusion on the kidney could have been mediated in part by the improvements in renal microvascular oxygenation and sepsis-induced endothelial dysfunction via the restoration of eNOS expression within the kidney. Electronic supplementary material The online version of this article (doi:10.1186/s13054-016-1581-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lara Zafrani
- Department of Translational Physiology, Academic Medical Center, Amsterdam, The Netherlands
| | - Bulent Ergin
- Department of Intensive Care, Erasmus MC, University of Medical Center, Rotterdam, The Netherlands
| | - Aysegul Kapucu
- Department of Biology, Faculty of Science, University of Istanbul, Istanbul, Turkey
| | - Can Ince
- Department of Intensive Care, Erasmus MC, University of Medical Center, Rotterdam, The Netherlands.
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31
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Krömker M, Lauscher P, Kertscho H, Zacharowski K, Rosenberger P, Meier J. Anemia tolerance during normo-, hypo-, and hypervolemia. Transfusion 2016; 57:613-621. [PMID: 27990642 DOI: 10.1111/trf.13942] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 10/23/2016] [Accepted: 10/24/2016] [Indexed: 01/10/2023]
Abstract
BACKGROUND Restrictive intraoperative fluid management has been demonstrated to improve outcome of visceral and lung surgery in several studies. However, subsequent hypovolemia (HOV) may be accompanied by a decrease of anemia tolerance, resulting in increased transfusion needs. We therefore investigated the effect of volume status on anemia tolerance. STUDY DESIGN AND METHODS Eighteen domestic pigs of either sex (mean weight, 23.5 ± 4.8 kg) were anesthetized, ventilated, and randomized into three experimental groups: normovolemia (no intervention), HOV (blood loss of 40% of blood volume), and hypervolemia (HEV; volume infusion of 40% of blood volume). The animals were then hemodiluted until their individual critical hemoglobin concentrations (Hbcrit ) were reached by the exchange of whole blood for hydroxyethyl starch (HES; 130:0.4). Subsequently, organ-specific hypoxia was assessed using pimonidazole tissue staining in relevant organs. Hemodynamic and metabolic variables were also investigated. RESULTS Despite significant differences in exchangeable blood volume, Hbcrit was the same in all groups (2.3 g/dL, NS). During HOV, tissue hypoxia was aggravated in the myocardium, brain, and kidneys, whereas tissue oxygenation of the liver and intestine was not influenced by volume status. HEV increased tissue hypoxia in the lungs, but did not impact tissue oxygenation of other organs. CONCLUSIONS The combination of hemorrhagic HOV with subsequent anemia leads to accentuated tissue hypoxia, revealed by a significant increase in pimonidazole binding at Hbcrit , in heart, lungs, brain, and kidney. The lungs were the only organ that showed increased tissue hypoxia after pretreatment of HES infusion and subsequent anemia by normovolemic hemodilution.
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Affiliation(s)
- Malte Krömker
- Clinic of Anesthesiology, Intensive Care Medicine and Pain Therapy, Sana Klinikum Offenbach, Offenbach, Germany
| | - Patrick Lauscher
- Clinic of Anesthesiology, Intensive Care Medicine and Pain Therapy, Sana Klinikum Offenbach, Offenbach, Germany
| | - Harry Kertscho
- Department of Anesthesiology and Critical Care Medicine, University Hospital Mannheim, Faculty of Medicine, University of Heidelberg, Heidelberg, Germany
| | - Kai Zacharowski
- Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, University Hospital Frankfurt, Frankfurt am Main, Germany
| | - Peter Rosenberger
- Clinic for Anesthesiology and Intensive Care Medicine, Eberhard Karls University, Tübingen, Germany
| | - Jens Meier
- Department of Anesthesiology and Critical Care Medicine, Faculty of Medicine of the Kepler University, Linz, Austria
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Cutaneous Mitochondrial Po2, but Not Tissue Oxygen Saturation, Is an Early Indicator of the Physiologic Limit of Hemodilution in the Pig. Anesthesiology 2016; 125:124-32. [DOI: 10.1097/aln.0000000000001156] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Abstract
Background
Hemodilution is a consequence of fluid replacement during blood loss and is limited by the individual ability to compensate for decreasing hemoglobin level. We tested the ability of a novel noninvasive method for measuring cutaneous mitochondrial Po2 (mitoPo2) to detect this threshold early.
Methods
Anesthetized and ventilated pigs were hemodynamically monitored and randomized into a hemodilution (n = 12) or a time control (TC) group (n = 14). MitoPo2 measurements were done by oxygen-dependent delayed fluorescence of protoporphyrin IX after preparation of the skin with 20% 5-aminolevulinic acid cream. Tissue oxygen saturation (StO2) was measured with near infrared spectroscopy on the thoracic wall. After baseline measurements, progressive normovolemic hemodilution was performed in the hemodilution group in equal steps (500 ml blood replaced by 500 ml Voluven®; Fresenius Kabi AG, Germany). Consecutive measurements were performed after 20-min stabilization periods and repeated 8 times or until the animal died.
Results
The TC animals remained stable with regard to hemodynamics and mitoPo2. In the hemodilution group, mitoPo2 became hemoglobin-dependent after reaching a threshold of 2.6 ± 0.2 g/dl. During hemodilution, hemoglobin and mitoPo2 decreased (7.9 ± 0.2 to 2.1 ± 0.2 g/dl; 23.6 ± 2 to 9.9 ± 0.8 mmHg), but StO2 did not. Notably, mitoPo2 dropped quite abruptly (about 39%) at the individual threshold. We observed that this decrease in mitoPo2 occurred at least one hemodilution step before changes in other conventional parameters.
Conclusions
Cutaneous mitoPo2 decreased typically one hemodilution step before occurrence of significant alterations in systemic oxygen consumption and lactate levels. This makes mitoPo2 a potential early indicator of the physiologic limit of hemodilution and possibly a physiologic trigger for blood transfusion.
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33
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Evans RG. Oxygen regulation in biological systems. Am J Physiol Regul Integr Comp Physiol 2016; 310:R673-8. [PMID: 26911461 DOI: 10.1152/ajpregu.00004.2016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 02/17/2016] [Indexed: 01/25/2023]
Affiliation(s)
- Roger G Evans
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, Melbourne, Australia
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Ince C, Mik EG. Microcirculatory and mitochondrial hypoxia in sepsis, shock, and resuscitation. J Appl Physiol (1985) 2016; 120:226-35. [DOI: 10.1152/japplphysiol.00298.2015] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 06/05/2015] [Indexed: 12/23/2022] Open
Abstract
After shock, persistent oxygen extraction deficit despite the apparent adequate recovery of systemic hemodynamic and oxygen-derived variables has been a source of uncertainty and controversy. Dysfunction of oxygen transport pathways during intensive care underlies the sequelae that lead to organ failure, and the limitations of techniques used to measure tissue oxygenation in vivo have contributed to the lack of progress in this area. Novel techniques have provided detailed quantitative insight into the determinants of microcirculatory and mitochondrial oxygenation. These techniques, which are based on the oxygen-dependent quenching of phosphorescence or delayed luminescence are briefly reviewed. The application of these techniques to animal models of shock and resuscitation revealed the heterogeneous nature of oxygen distributions and the alterations in oxygen distribution in the microcirculation and in mitochondria. These studies identified functional shunting in the microcirculation as an underlying cause of oxygen extraction deficit observed in states of shock and resuscitation. The translation of these concepts to the bedside has been enabled by our development and clinical introduction of hand-held microscopy. This tool facilitates the direct observation of the microcirculation and its alterations at the bedside under the conditions of shock and resuscitation. Studies identified loss of coherence between the macrocirculation and the microcirculation, in which resuscitation successfully restored systemic circulation but did not alleviate microcirculatory perfusion alterations. Various mechanisms responsible for these alterations underlie the loss of hemodynamic coherence during unsuccessful resuscitation procedures. Therapeutic resolution of persistent heterogeneous microcirculatory alterations is expected to improve outcomes in critically ill patients.
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Affiliation(s)
- Can Ince
- Department of Intensive Care, Erasmus MC, University Medical Center, Rotterdam
- Department of Translational Physiology, Academic Medical Center, Amsterdam, The Netherlands
| | - Egbert G. Mik
- Department of Intensive Care, Erasmus MC, University Medical Center, Rotterdam
- Department of Anesthesiology, Erasmus MC, University Medical Center, Rotterdam; and
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Ince C. Hemodynamic coherence and the rationale for monitoring the microcirculation. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2015; 19 Suppl 3:S8. [PMID: 26729241 PMCID: PMC4699073 DOI: 10.1186/cc14726] [Citation(s) in RCA: 305] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This article presents a personal viewpoint of the shortcoming of conventional hemodynamic resuscitation procedures in achieving organ perfusion and tissue oxygenation following conditions of shock and cardiovascular compromise, and why it is important to monitor the microcirculation in such conditions. The article emphasizes that if resuscitation procedures are based on the correction of systemic variables, there must be coherence between the macrocirculation and microcirculation if systemic hemodynamic-driven resuscitation procedures are to be effective in correcting organ perfusion and oxygenation. However, in conditions of inflammation and infection, which often accompany states of shock, vascular regulation and compensatory mechanisms needed to sustain hemodynamic coherence are lost, and the regional circulation and microcirculation remain in shock. We identify four types of microcirculatory alterations underlying the loss of hemodynamic coherence: type 1, heterogeneous microcirculatory flow; type 2, reduced capillary density induced by hemodilution and anemia; type 3, microcirculatory flow reduction caused by vasoconstriction or tamponade; and type 4, tissue edema. These microcirculatory alterations can be observed at the bedside using direct visualization of the sublingual microcirculation with hand-held vital microscopes. Each of these alterations results in oxygen delivery limitation to the tissue cells despite the presence of normalized systemic hemodynamic variables. Based on these concepts, we propose how to optimize the volume of fluid to maximize the oxygen-carrying capacity of the microcirculation to transport oxygen to the tissues.
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Lee ES, Kim MJ, Park BR, Kim JS, Choi GY, Lee JJ, Lee IS. Avoiding unnecessary blood transfusions in women with profound anaemia. Aust N Z J Obstet Gynaecol 2015; 55:262-7. [PMID: 26044165 DOI: 10.1111/ajo.12329] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Accepted: 01/23/2015] [Indexed: 12/18/2022]
Abstract
BACKGROUND Blood transfusions may be associated with risks and the risk: benefit ratio is not always clear, even in the setting of haemorrhage. AIMS To describe the management practices and outcomes in women with profound anaemia who refused blood transfusion. MATERIALS AND METHODS Retrospective analysis over a 10-year time frame of severely anaemic women (Hb <50 g/L) with benign conditions who had requested not to receive a blood transfusion. Demographic data, clinical presentation, anaemia management practice and serious adverse events were collected from the medical record charts. Women were analysed in two groups: a gynaecologic (Gyn) and an obstetric (Ob) population. RESULTS A total of 19 women (12 Gyn and 7 Ob) met the inclusion criteria with a mean age of 35.8 ± 10.2 years. The lowest mean Hb concentration was 41.3 ± 9.7 g/L (Gyn Group) and 36.0 ± 8.9 g/L (Ob Group) which increased, to 67.3 ± 14.3 g/L and 73.1 ± 6.9 g/L, respectively, by the time of hospital discharge. Anaemia management initially addressed the underlying etiology and was followed by intravenous iron (all cases) plus erythropoiesis stimulating agents, haemocoagulase and/or fluids. The mean length of hospital stay was 10.5 ± 4.4 and 13.7 ± 4.1 days for the Gyn and Ob groups, respectively. No deaths or other serious complications occurred. CONCLUSION These findings suggest that young and otherwise healthy women can tolerate profound anaemia (Hb <50 g/L) permitting corrective strategies to be successfully implemented without the need for blood transfusion.
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Affiliation(s)
- Eun Sil Lee
- Department of Obstetrics and Gynecology, Soonchunhyang University Seoul Hospital, Seoul, Korea
| | - Min Jung Kim
- Department of Obstetrics and Gynecology, Soonchunhyang University Seoul Hospital, Seoul, Korea
| | - Bo Ra Park
- Department of Obstetrics and Gynecology, Soonchunhyang University Seoul Hospital, Seoul, Korea
| | - Jeong Sig Kim
- Department of Obstetrics and Gynecology, Soonchunhyang University Seoul Hospital, Seoul, Korea
| | - Gyu Yeon Choi
- Department of Obstetrics and Gynecology, Soonchunhyang University Seoul Hospital, Seoul, Korea
| | - Jeong Jae Lee
- Department of Obstetrics and Gynecology, Soonchunhyang University Seoul Hospital, Seoul, Korea
| | - Im Soon Lee
- Department of Obstetrics and Gynecology, Soonchunhyang University Seoul Hospital, Seoul, Korea
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Casans Francés R, Ripollés Melchor J, Calvo Vecino JM. Is it time to integrate patient blood management in ERAS guidelines? REVISTA ESPANOLA DE ANESTESIOLOGIA Y REANIMACION 2015; 62:61-63. [PMID: 25605130 DOI: 10.1016/j.redar.2014.12.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 12/13/2014] [Accepted: 12/16/2014] [Indexed: 06/04/2023]
Affiliation(s)
- R Casans Francés
- Department of Anesthesia, Hospital Clínico Universitario Lozano Blesa, Zaragoza, Spain; Grupo Español de Rehabilitación Multimodal (GERM)/ERAS-Spain.
| | - J Ripollés Melchor
- Department of Anesthesia, Hospital Universitario Infanta Leonor, Madrid, Spain; Grupo Español de Rehabilitación Multimodal (GERM)/ERAS-Spain
| | - J M Calvo Vecino
- Department of Anesthesia, Hospital Universitario Infanta Leonor, Madrid, Spain; Grupo Español de Rehabilitación Multimodal (GERM)/ERAS-Spain
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Orlov YP, Lukach VN, Govorova NV, Baytugaeva GA. [Fear of anemia or why don't we afraid of blood transfusion?]. Khirurgiia (Mosk) 2015:88-94. [PMID: 27010036 DOI: 10.17116/hirurgia20151188-94] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Affiliation(s)
- Yu P Orlov
- Chair of Anesthesiology and Intensive Care of Omsk State Medical Academy, Russian Ministry of Health, Omsk, Russia
| | - V N Lukach
- Chair of Anesthesiology and Intensive Care of Omsk State Medical Academy, Russian Ministry of Health, Omsk, Russia
| | - N V Govorova
- Chair of Anesthesiology and Intensive Care of Omsk State Medical Academy, Russian Ministry of Health, Omsk, Russia
| | - G A Baytugaeva
- Chair of Anesthesiology and Intensive Care of Omsk State Medical Academy, Russian Ministry of Health, Omsk, Russia
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Koch CG. Tolerating anemia: taking aim at the right target before pulling the transfusion trigger. Transfusion 2014; 54:2595-7. [DOI: 10.1111/trf.12832] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Colleen G. Koch
- Department of Cardiothoracic Anesthesia; Cleveland Clinic; Cleveland OH
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Tsui AKY, Marsden PA, Mazer CD, Sled JG, Lee KM, Henkelman RM, Cahill LS, Zhou YQ, Chan N, Liu E, Hare GMT. Differential HIF and NOS responses to acute anemia: defining organ-specific hemoglobin thresholds for tissue hypoxia. Am J Physiol Regul Integr Comp Physiol 2014; 307:R13-25. [DOI: 10.1152/ajpregu.00411.2013] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Tissue hypoxia likely contributes to anemia-induced organ injury and mortality. Severe anemia activates hypoxia-inducible factor (HIF) signaling by hypoxic- and neuronal nitric oxide (NO) synthase- (nNOS) dependent mechanisms. However, organ-specific hemoglobin (Hb) thresholds for increased HIF expression have not been defined. To assess organ-specific Hb thresholds for tissue hypoxia, HIF-α (oxygen-dependent degradation domain, ODD) luciferase mice were hemodiluted to mild, moderate, or severe anemia corresponding to Hb levels of 90, 70, and 50 g/l, respectively. HIF luciferase reporter activity, HIF protein, and HIF-dependent RNA levels were assessed. In the brain, HIF-1α was paradoxically decreased at mild anemia, returned to baseline at moderate anemia, and then increased at severe anemia. Brain HIF-2α remained unchanged at all Hb levels. Both kidney HIF-1α and HIF-2α increased earlier (Hb ∼70–90 g/l) in response to anemia. Liver also exhibited an early HIF-α response. Carotid blood flow was increased early (Hb ∼70, g/l), but renal blood flow remained relatively constant, only increased at Hb of 50 g/l. Anemia increased nNOS (brain and kidney) and endothelia NOS (eNOS) (kidney) levels. Whereas anemia-induced increases in brain HIFα were nNOS-dependent, our current data demonstrate that increased renal HIFα was nNOS independent. HIF-dependent RNA levels increased linearly (∼10-fold) in the brain. However, renal HIF-RNA responses (MCT4, EPO) increased exponentially (∼100-fold). Plasma EPO levels increased near Hb threshold of 90 g/l, suggesting that the EPO response is sensitive. Collectively, these observations suggest that each organ expresses a different threshold for cellular HIF/NOS hypoxia responses. This knowledge may help define the mechanism(s) by which the brain and kidney maintain oxygen homeostasis during anemia.
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Affiliation(s)
- Albert K. Y. Tsui
- Department of Anesthesia, St. Michael's Hospital, University of Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
| | - Philip A. Marsden
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
- Department of Medicine, Division of Nephrology, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - C. David Mazer
- Department of Anesthesia, St. Michael's Hospital, University of Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - John G. Sled
- Department of Medical Biophysics, University of Toronto, Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Keith M. Lee
- Department of Anesthesia, St. Michael's Hospital, University of Toronto, Ontario, Canada
| | - R. Mark Henkelman
- Department of Medical Biophysics, University of Toronto, Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Lindsay S. Cahill
- Department of Medical Biophysics, University of Toronto, Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Yu-Qing Zhou
- Department of Medical Biophysics, University of Toronto, Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Neville Chan
- Department of Anesthesia, St. Michael's Hospital, University of Toronto, Ontario, Canada
| | - Elaine Liu
- Department of Anesthesia, St. Michael's Hospital, University of Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
| | - Gregory M. T. Hare
- Department of Anesthesia, St. Michael's Hospital, University of Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
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Evans RG. Hypoxic signaling: some organs are more equal than others. Focus on "Differential HIF and NOS responses to acute anemia: defining organ-specific hemoglobin thresholds for tissue hypoxia". Am J Physiol Regul Integr Comp Physiol 2014; 307:R11-2. [PMID: 24760993 DOI: 10.1152/ajpregu.00524.2013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Roger G Evans
- Department of Physiology, Monash University, Melbourne, Australia
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42
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Hare GMT. Tolerance of anemia: understanding the adaptive physiological mechanisms which promote survival. Transfus Apher Sci 2013; 50:10-2. [PMID: 24433778 DOI: 10.1016/j.transci.2013.12.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Acute anemia and hemodilution are associated with increased organ injury (brain, kidney) and mortality in patients undergoing surgery. A more complete understanding of the adaptive physiological mechanisms which maintain tissue oxygen delivery, and the hemoglobin concentration at which these mechanisms are overwhelmed, would help to direct treatments to improve event free survival in patients who experience acute anemia. Adaptive cardiovascular and cellular responses are key to maintaining survival during acute anemia. We have identified neuronal nitric oxide synthase (nNOS) and hypoxia inducible factor (HIF) promote survival during acute anemia in animal models. In addition, activation of tissue nNOS may promote oxidation of hemoglobin to methemoglobin: a potential biomarker of anemia-induced tissue hypoxia. We continue to explore the possibility that methemoglobin, and other hypoxic signaling molecules, may be biomarkers of anemia induced tissue hypoxia which can be used to guide optimal treatment of anemic patents.
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Affiliation(s)
- Gregory M T Hare
- Department of Anesthesia, St. Michael's Hospital, University of Toronto, Keenan Research Centre in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, 30 Bond Street, Toronto, Ontario M5B 1W8, Canada; Department of Physiology, University of Toronto, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.
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Understanding intestinal circulation – Many barriers, many unknowns. TRENDS IN ANAESTHESIA AND CRITICAL CARE 2013. [DOI: 10.1016/j.tacc.2013.08.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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44
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Hare GM, Tsui AK, Ozawa S, Shander A. Anaemia: Can we define haemoglobin thresholds for impaired oxygen homeostasis and suggest new strategies for treatment? Best Pract Res Clin Anaesthesiol 2013; 27:85-98. [DOI: 10.1016/j.bpa.2012.12.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 12/17/2012] [Indexed: 12/30/2022]
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Abdelmalak B, Cata J, Bonilla A, You J, Kopyeva T, Vogel J, Campbell S, Sessler D. Intraoperative tissue oxygenation and postoperative outcomes after major non-cardiac surgery: an observational study. Br J Anaesth 2013; 110:241-249. [DOI: 10.1093/bja/aes378] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
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Evans RG, Ince C, Joles JA, Smith DW, May CN, O'Connor PM, Gardiner BS. Haemodynamic influences on kidney oxygenation: Clinical implications of integrative physiology. Clin Exp Pharmacol Physiol 2013; 40:106-22. [DOI: 10.1111/1440-1681.12031] [Citation(s) in RCA: 178] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 10/21/2012] [Accepted: 11/15/2012] [Indexed: 01/08/2023]
Affiliation(s)
- Roger G Evans
- Department of Physiology; Monash University; Melbourne; Victoria; Australia
| | - Can Ince
- Department of Translational Physiology; Academic Medical Center; University of Amsterdam; Amsterdam; The Netherlands
| | - Jaap A Joles
- Department of Nephrology and Hypertension; University Medical Center; Utrecht; The Netherlands
| | - David W Smith
- School of Computer Science and Software Engineering; The University of Western Australia; Perth; Western Australia; Australia
| | - Clive N May
- Florey Institute of Neuroscience and Mental Health; University of Melbourne; Melbourne; Victoria; Australia
| | - Paul M O'Connor
- Department of Physiology; Georgia Health Sciences University; Augusta; GA; USA
| | - Bruce S Gardiner
- School of Computer Science and Software Engineering; The University of Western Australia; Perth; Western Australia; Australia
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Almac E, Aksu U, Bezemer R, Jong W, Kandil A, Yuruk K, Demirci-Tansel C, Ince C. The acute effects of acetate-balanced colloid and crystalloid resuscitation on renal oxygenation in a rat model of hemorrhagic shock. Resuscitation 2012; 83:1166-72. [PMID: 22353638 DOI: 10.1016/j.resuscitation.2012.02.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Revised: 12/22/2011] [Accepted: 02/07/2012] [Indexed: 01/09/2023]
Abstract
INTRODUCTION Fluid resuscitation therapy is the initial step of treatment for hemorrhagic shock. In the present study we aimed to investigate the acute effects of acetate-balanced colloid and crystalloid resuscitation on renal oxygenation in a rat model of hemorrhagic shock. We hypothesized that acetate-balanced solutions would be superior in correcting impaired renal perfusion and oxygenation after severe hemorrhage compared to unbalanced solutions. METHODS In anesthetized, mechanically ventilated rats, hemorrhagic shock was induced by withdrawing blood from the femoral artery until mean arterial pressure (MAP) was reduced to 30 mmHg. One hour later, animals were resuscitated with either hydroxyethyl starch (HES, 130/0.42 kDa) dissolved in saline (HES-NaCl; n=6) or a acetate-balanced Ringer's solution (HES-RA; n=6), as well as with acetated Ringer's solution (RA; n=6) or 0.9% NaCl alone (NaCl; n=6) until a target MAP of 80 mmHg was reached. Oxygen tension in the renal cortex (CμPO2), outer medulla (MμPO2), and renal vein were measured using phosphorimetry. RESULTS Hemorrhagic shock (MAP=30 mmHg) significantly decreased renal oxygenation and oxygen consumption. Restoring the MAP to 80 mmHg required 24.8±1.7 ml of NaCl, 21.7±1.4 ml of RA, 5.9±0.5 ml of HES-NaCl (p<0.05 vs. NaCl and RA), and 6.0±0.4 ml of HES-RA (p<0.05 vs. NaCl and RA). NaCl, RA, and HES-NaCl resuscitation led to hyperchloremic acidosis, while HES-RA resuscitation did not. Only HES-RA resuscitation could restore renal blood flow back to ∼85% of baseline level (from 1.9±0.1 ml/min during shock to 5.1 ml±0.2 ml/min 60 min after HES-RA resuscitation) which was associated with an improved renal oxygenation (CμPO2 increased from 24±2 mmHg during shock to 50±2 mmHg 60 min after HES-RA resuscitation) albeit not to baseline level. At the end of the protocol, creatinine clearance was decreased in all groups with no differences between the different resuscitation groups. CONCLUSION While resuscitation with the NaCl and RA (crystalloid solutions) and the HES-NaCl (unbalanced colloid solution) led to hyperchloremic acidosis, resuscitation with the HES-RA (acetate-balanced colloid solution) did not. The HES-RA was furthermore the only fluid restoring renal blood flow back to ∼85% of baseline level and most prominently improved renal microvascular oxygenation.
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Affiliation(s)
- Emre Almac
- Department of Translational Physiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Shander A, Javidroozi M, Ozawa S, Hare G. What is really dangerous: anaemia or transfusion? Br J Anaesth 2011; 107 Suppl 1:i41-59. [DOI: 10.1093/bja/aer350] [Citation(s) in RCA: 350] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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Low hemoglobin levels during normovolemia are associated with electrocardiographic changes in pigs. Shock 2011; 35:375-81. [PMID: 20856175 DOI: 10.1097/shk.0b013e3181f6aa44] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We studied whether low hemoglobin concentrations during normovolemia change the myocardial electrical current (electrocardiogram) in a pig model. Normovolemic anemia was achieved by stepwise replacing blood with colloids (hydroxyethyl starch 6%). We measured the length of the PQ-, QT-, QTc, and the ST interval as well as the amplitude of the Q wave and T wave at hemoglobin concentrations of 9.5, 8.0, 5.5, 3.8, and 3.3 g·dL. Normovolemic anemia is accompanied by a gradual prolongation of the QT and QTc interval and a reduction in the amplitude of the T wave. The QRS complex is partly diminished in amplitude. Results were verified performing a time-frequency analysis on single heartbeats. During severe anemia and normovolemia, electrocardiographic changes can be detected. Further investigations are warranted to elucidate whether these changes indicate myocardial hypoxia.
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Bezemer R, Faber DJ, Almac E, Kalkman J, Legrand M, Heger M, Ince C. Evaluation of multi-exponential curve fitting analysis of oxygen-quenched phosphorescence decay traces for recovering microvascular oxygen tension histograms. Med Biol Eng Comput 2010; 48:1233-42. [PMID: 21046272 PMCID: PMC2993890 DOI: 10.1007/s11517-010-0698-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Accepted: 10/08/2010] [Indexed: 11/29/2022]
Abstract
Although it is generally accepted that oxygen-quenched phosphorescence decay traces can be analyzed using the exponential series method (ESM), its application until now has been limited to a few (patho)physiological studies, probably because the reliability of the recovered oxygen tension (pO(2)) histograms has never been extensively evaluated and lacks documentation. The aim of this study was, therefore, to evaluate the use of the ESM to adequately determine pO(2) histograms from phosphorescence decay traces. For this purpose we simulated decay traces corresponding to uni- and bimodal pO(2) distributions and recovered the pO(2) histograms at different signal-to-noise ratios (SNRs). Ultimately, we recovered microvascular pO(2) histograms measured in the rat kidney in a model of endotoxemic shock and fluid resuscitation and showed that the mean microvascular oxygen tension, [Symbol: see text]pO(2)[Symbol: see text], decreased after induction of endotoxemia and that after 2 h of fluid resuscitation, [Symbol: see text]pO(2)[Symbol: see text] remained low, but the hypoxic peak that had arisen during endotoxemia was reduced. This finding illustrates the importance of recovering pO(2) histograms under (patho)physiological conditions. In conclusion, this study has characterized how noise affects the recovery of pO(2) histograms using the ESM and documented the reliability of the ESM for recovering both low- and high-pO(2) distributions for SNRs typically found in experiments. This study might therefore serve as a frame of reference for investigations focused on oxygen (re)distribution during health and disease and encourage researchers to (re-)analyze data obtained in (earlier) studies possibly revealing new insights into complex disease states and treatment strategies.
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Affiliation(s)
- Rick Bezemer
- Department of Translational Physiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
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