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Antonucci E, Prado VE, Legrand M. Breaking Down the Evidence: Does Perioperative Hypotension Cause Kidney Injury? Nephron Clin Pract 2023; 147:737-742. [PMID: 37423203 DOI: 10.1159/000531335] [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: 03/29/2023] [Accepted: 05/23/2023] [Indexed: 07/11/2023] Open
Abstract
BACKGROUND Acute kidney injury (AKI) is common in the postoperative period and is associated with negative patient outcomes. The definition of perioperative hypotension is wide, but it is associated with various complications, including AKI. SUMMARY Preclinical data suggest that sustained severe renal hypoperfusion per se does not cause persistent AKI. The evidence associating blood pressure levels and postoperative renal dysfunction is predominantly retrospective and observational, and therefore potentially misled by the complex interactions between exposures, confounders, and mediators. KEY MESSAGES To better understand how perioperative hemodynamic management could affect the occurrence of kidney injury, it is pivotal to further investigate the association between hypotension and kidney dysfunction in the perioperative period and determine the degree to which hypotension is a causal factor.
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Affiliation(s)
- Edoardo Antonucci
- Department of Anesthesiology and Perioperative Care, University of California, San Francisco, California, USA
- Department of Anesthesia and Critical Care Medicine, University of Milan, Milan, Italy
| | - Victor E Prado
- Department of Nephrology, University of California, San Francisco, California, USA
| | - Matthieu Legrand
- Department of Anesthesiology and Perioperative Care, University of California, San Francisco, California, USA
- INI-CRCT Network, Nancy, France
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Ruiz-Sánchez JG, Cuesta M, Gómez-Hoyos E, Cárdenas-Salas J, Rubio-Herrera MÁ, Martínez-González E, De Miguel Novoa P, Ternero-Vega JE, Calle-Pascual AL, Runkle I. Changes in Serum Creatinine Levels Can Help Distinguish Hypovolemic from Euvolemic Hyponatremia. MEDICINA (KAUNAS, LITHUANIA) 2022; 58:medicina58070851. [PMID: 35888570 PMCID: PMC9323891 DOI: 10.3390/medicina58070851] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/15/2022] [Accepted: 06/22/2022] [Indexed: 01/17/2023]
Abstract
Background and Objectives: Differentiating between hypovolemic (HH) and euvolemic hyponatremia (EH) is crucial for correct diagnosis and therapy, but can be a challenge. We aim to ascertain whether changes in serum creatinine (SC) can be helpful in distinguishing HH from EH. Materials and Methods: Retrospective analysis of patients followed in a monographic hyponatremia outpatient clinic of a tertiary hospital during 1 January 2014−30 November 2019. SC changes during HH and EH from eunatremia were studied. The diagnostic accuracy of the SC change from eunatremia to hyponatremia (∆SC) was analyzed. Results: A total of 122 hyponatremic patients, median age 79 years (70−85), 46.7% women. In total, 70/122 patients had EH, 52/122 HH. During hyponatremia, median SC levels increased in the HH group: +0.18 mg/dL [0.09−0.39, p < 0.001], but decreased in the EH group: −0.07 mg/dL (−0.15−0.02, p < 0.001), as compared to SC in eunatremia. HH subjects presented a higher rate of a positive ∆SC than EH (90.4% vs. 25.7%, p < 0.001). EH subjects presented a higher rate of a negative/null ∆SC than HH (74.3% vs. 9.6%, p < 0.001). ROC curve analysis found an AUC of 0.908 (95%CI: 0.853 to 0.962, p < 0.001) for ∆SC%. A ∆SC% ≥ 10% had an OR of 29.0 (95%CI: 10.3 to 81.7, p < 0.001) for HH. A ∆SC% ≤ 3% had an OR of 68.3 (95%CI: 13.0 to 262.2, p < 0.001) for EH. Conclusions: The assessment of SC changes from eunatremia to hyponatremia can be useful in distinguishing between HH and EH.
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Affiliation(s)
- Jorge Gabriel Ruiz-Sánchez
- Departamento de Endocrinología, Hospital Universitario Fundación Jiménez Díaz, 28040 Madrid, Spain;
- Servicio de Endocrinología y Nutrición, Instituto de Investigación Sanitaria San Carlos (IdISSC), Hospital Clínico San Carlos, 28040 Madrid, Spain; (M.C.); (M.Á.R.-H.); (P.D.M.N.); (A.L.C.-P.); (I.R.)
- Correspondence:
| | - Martín Cuesta
- Servicio de Endocrinología y Nutrición, Instituto de Investigación Sanitaria San Carlos (IdISSC), Hospital Clínico San Carlos, 28040 Madrid, Spain; (M.C.); (M.Á.R.-H.); (P.D.M.N.); (A.L.C.-P.); (I.R.)
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain
| | - Emilia Gómez-Hoyos
- Servicio de Endocrinología y Nutrición, Hospital Clínico Universitario de Valladolid, 47003 Valladolid, Spain;
| | - Jersy Cárdenas-Salas
- Departamento de Endocrinología, Hospital Universitario Fundación Jiménez Díaz, 28040 Madrid, Spain;
| | - Miguel Ángel Rubio-Herrera
- Servicio de Endocrinología y Nutrición, Instituto de Investigación Sanitaria San Carlos (IdISSC), Hospital Clínico San Carlos, 28040 Madrid, Spain; (M.C.); (M.Á.R.-H.); (P.D.M.N.); (A.L.C.-P.); (I.R.)
| | - Estefanía Martínez-González
- Servicio de Análisis Clínicos, Instituto de Medicina de Laboratorio, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria San Carlos (IdISSC), 28040 Madrid, Spain;
| | - Paz De Miguel Novoa
- Servicio de Endocrinología y Nutrición, Instituto de Investigación Sanitaria San Carlos (IdISSC), Hospital Clínico San Carlos, 28040 Madrid, Spain; (M.C.); (M.Á.R.-H.); (P.D.M.N.); (A.L.C.-P.); (I.R.)
| | | | - Alfonso Luis Calle-Pascual
- Servicio de Endocrinología y Nutrición, Instituto de Investigación Sanitaria San Carlos (IdISSC), Hospital Clínico San Carlos, 28040 Madrid, Spain; (M.C.); (M.Á.R.-H.); (P.D.M.N.); (A.L.C.-P.); (I.R.)
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain
| | - Isabelle Runkle
- Servicio de Endocrinología y Nutrición, Instituto de Investigación Sanitaria San Carlos (IdISSC), Hospital Clínico San Carlos, 28040 Madrid, Spain; (M.C.); (M.Á.R.-H.); (P.D.M.N.); (A.L.C.-P.); (I.R.)
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Langaa SS, Lauridsen TG, Mose FH, Fynbo CA, Theil J, Bech JN. Estimation of renal perfusion based on measurement of rubidium-82 clearance by PET/CT scanning in healthy subjects. EJNMMI Phys 2021; 8:43. [PMID: 34057645 PMCID: PMC8167076 DOI: 10.1186/s40658-021-00389-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 05/12/2021] [Indexed: 11/18/2022] Open
Abstract
Background Changes in renal blood flow (RBF) may play a pathophysiological role in hypertension and kidney disease. However, RBF determination in humans has proven difficult. We aimed to confirm the feasibility of RBF estimation based on positron emission tomography/computed tomography (PET/CT) and rubidium-82 (82Rb) using the abdominal aorta as input function in a 1-tissue compartment model. Methods Eighteen healthy subjects underwent two dynamic 82Rb PET/CT scans in two different fields of view (FOV). FOV-A included the left ventricular blood pool (LVBP), the abdominal aorta (AA) and the majority of the kidneys. FOV-B included AA and the kidneys in their entirety. In FOV-A, an input function was derived from LVBP and from AA, in FOV-B from AA. One-tissue compartmental modelling was performed using tissue time activity curves generated from volumes of interest (VOI) contouring the kidneys, where the renal clearance of 82Rb is represented by the K1 kinetic parameter. Total clearance for both kidneys was calculated by multiplying the K1 values with the volume of VOIs used for analysis. Intra-assay coefficients of variation and inter-observer variation were calculated. Results For both kidneys, K1 values derived from AA did not differ significantly from values obtained from LVBP, neither were significant differences seen between AA in FOV-A and AA in FOV-B, nor between the right and left kidneys. For both kidneys, the intra-assay coefficients of variation were low (~ 5%) for both input functions. The measured K1 of 2.80 ml/min/cm3 translates to a total clearance for both kidneys of 766 ml/min/1.73 m2. Conclusion Measurement of renal perfusion based on PET/CT and 82Rb using AA as input function in a 1-tissue compartment model is feasible in a single FOV. Based on previous studies showing 82Rb to be primarily present in plasma, the measured K1 clearance values are most likely representative of effective renal plasma flow (ERPF) rather than estimated RBF values, but as the accurate calculation of total clearance/flow is very much dependent on the analysed volume, a standardised definition for the employed renal volumes is needed to allow for proper comparison with standard ERPF and RBF reference methods. Supplementary Information The online version contains supplementary material available at 10.1186/s40658-021-00389-0.
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Affiliation(s)
- Stine Sundgaard Langaa
- Gødstrup HospitalUniversity Clinic in Nephrology and Hypertension, Department of Medical Research, Gødstrup Hospital and Aarhus University, Lægaardvej 12J, 7500, Holstebro, Denmark.
| | - Thomas Guldager Lauridsen
- Gødstrup HospitalUniversity Clinic in Nephrology and Hypertension, Department of Medical Research, Gødstrup Hospital and Aarhus University, Lægaardvej 12J, 7500, Holstebro, Denmark
| | - Frank Holden Mose
- Gødstrup HospitalUniversity Clinic in Nephrology and Hypertension, Department of Medical Research, Gødstrup Hospital and Aarhus University, Lægaardvej 12J, 7500, Holstebro, Denmark
| | | | - Jørn Theil
- Department of Nuclear Medicine, Gødstrup Hospital, Herning, Denmark.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Jesper Nørgaard Bech
- Gødstrup HospitalUniversity Clinic in Nephrology and Hypertension, Department of Medical Research, Gødstrup Hospital and Aarhus University, Lægaardvej 12J, 7500, Holstebro, Denmark
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Abstract
Physical trauma can affect any individual and is globally accountable for more than one in every ten deaths. Although direct severe kidney trauma is relatively infrequent, extrarenal tissue trauma frequently results in the development of acute kidney injury (AKI). Various causes, including haemorrhagic shock, rhabdomyolysis, use of nephrotoxic drugs and infectious complications, can trigger and exacerbate trauma-related AKI (TRAKI), particularly in the presence of pre-existing or trauma-specific risk factors. Injured, hypoxic and ischaemic tissues expose the organism to damage-associated and pathogen-associated molecular patterns, and oxidative stress, all of which initiate a complex immunopathophysiological response that results in macrocirculatory and microcirculatory disturbances in the kidney, and functional impairment. The simultaneous activation of components of innate immunity, including leukocytes, coagulation factors and complement proteins, drives kidney inflammation, glomerular and tubular damage, and breakdown of the blood-urine barrier. This immune response is also an integral part of the intense post-trauma crosstalk between the kidneys, the nervous system and other organs, which aggravates multi-organ dysfunction. Necessary lifesaving procedures used in trauma management might have ambivalent effects as they stabilize injured tissue and organs while simultaneously exacerbating kidney injury. Consequently, only a small number of pathophysiological and immunomodulatory therapeutic targets for TRAKI prevention have been proposed and evaluated.
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Gomelsky A, Abreo K, Khater N, Abreo A, Amin B, Craig MK, Prabhakar A, Cornett EM, Urman RD, Kaye AD. Perioperative acute kidney injury: Stratification and risk reduction strategies. Best Pract Res Clin Anaesthesiol 2020; 34:167-182. [PMID: 32711827 DOI: 10.1016/j.bpa.2020.04.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 04/07/2020] [Indexed: 12/29/2022]
Abstract
Perioperative acute kidney injury (AKI) is associated with increased morbidity and mortality. Patient comorbidities, the type of surgery, timing of surgery, and exposure to nephrotoxins are important contributors for developing acute kidney injury. Urgent or emergent surgery, cardiac, and organ transplantation procedures are associated with a higher risk of acute kidney injury. Nephrotoxic drugs, contrast dye, and diuretics can worsen preexisting kidney dysfunction or act as an additive and/or synergistic insult to perioperative injury. A history of preoperative chronic kidney disease is the main risk factor for developing AKI, conferring as much as a 10-fold risk. However, beyond the preoperative renal function, the development of AKI is a complex phenomenon that involves a combination of patient-related and surgery-related factors.
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Affiliation(s)
- Alexander Gomelsky
- Department of Urology, LSU Health Shreveport, 1501 Kings Highway, Shreveport, LA, 71103, USA.
| | - Kenneth Abreo
- Department of Urology, LSU Health Shreveport, 1501 Kings Highway, Shreveport, LA, 71103, USA; Department of Nephrology and Hypertension, LSU Health Shreveport, 1501 Kings Highway, Shreveport, LA, 71103, USA.
| | - Nazih Khater
- Department of Urology, LSU Health Shreveport, 1501 Kings Highway, Shreveport, LA, 71103, USA.
| | - Adrian Abreo
- Division of Nephrology, Clerkship Director, Internal Medicine Clerkship, Associate Program Director, Adrian AbreoA, 71103, USA.
| | - Bakhtiar Amin
- Department of Nephrology and Hypertension, LSU Health Shreveport, 1501 Kings Highway, Shreveport, LA, 71103, USA.
| | - Madelyn K Craig
- Department of Anesthesiology, LSU Health Science Center New Orleans, 1542 Tulane Avenue, New Orleans, LA, 70112, USA.
| | - Amit Prabhakar
- Department of Anesthesiology, Division of Critical Care, Emory University School of Medicine, Atlanta, GA, USA.
| | - Elyse M Cornett
- Department of Anesthesiology, LSU Health Shreveport, 1501 Kings Highway, Shreveport, LA, 71103, USA.
| | - Richard D Urman
- Department of Anesthesiology, Perioperative and Pain Medicine, Harvard Medical School, Brigham and Women's Hospital, 75 Francis St, Boston, MA, 02115, USA.
| | - Alan D Kaye
- Departments of Anesthesiology and Pharmacology, Toxicology, and Neurosciences; Provost, Chief Academic Officer, and Vice Chancellor of Academic Affairs, LSU Health Shreveport, 1501 Kings Highway, Shreveport, LA, 71103, USA.
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Relationship Between Acute Kidney Injury and Fluid Overload: Are We Any Closer to the Truth? Pediatr Crit Care Med 2019; 20:1097-1098. [PMID: 31688683 DOI: 10.1097/pcc.0000000000002057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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7
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Perioperative urinary heat shock protein 72 as an early marker of acute kidney injury in dogs. Vet Anaesth Analg 2019; 47:53-60. [PMID: 31761601 DOI: 10.1016/j.vaa.2019.09.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 08/31/2019] [Accepted: 09/15/2019] [Indexed: 11/23/2022]
Abstract
OBJECTIVE Acute kidney injury (AKI) may be a complication in dogs undergoing surgery. Urinary heat shock protein 72 (uHSP72) is a sensitive biomarker of canine AKI. To assess the occurrence of perioperative AKI, based on uHSP72 compared with serum creatinine (sCr), and whether its occurrence is associated with the American Society of Anesthesiology physical status (ASA status). STUDY DESIGN Clinical prospective study. ANIMALS A total of 80 client-owned and shelter dogs. METHODS Dogs scheduled for elective or emergency surgery were assigned ASA status (ASA I-IV). Preoperative and 24 hour postoperative serum and urine samples were collected. sCr, uHSP72 and urinary creatinine (uCr) were measured. RESULTS Postoperative uHSP72/uCr concentration [median (range)] of all dogs undergoing surgery [2.40 (0.14-252) ng mg-1] was significantly increased compared with preoperative uHSP72/uCr [1.30 (0.11-142) ng mg-1] concentration (p < 0.001). Conversely, postoperative sCr concentration of all dogs [0.88 (0.3-1.6) mg dL-1] significantly decreased compared with preoperative sCr concentration [0.8 (0.2-5.0) mg dL-1; p = 0.001]. Median uHSP72/uCr concentration differed both preoperatively (p = 0.007) and postoperatively (p = 0.019) among the ASA status groups. Increased uHSP/uCr was measured in 20 dogs preoperatively and 33 dogs postoperatively, whereas only five dogs fulfilled the criteria of AKI based on sCr. CONCLUSIONS The occurrence of increased uHSP72/uCr perioperatively suggests that the proportion of dogs with AKI is considerably higher than perceived. CLINICAL RELEVANCE Dogs undergoing surgery should be closely monitored for AKI before and after anesthesia, using currently available markers (e.g., sCr) and more sensitive markers.
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8
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Renal Blood Flow Measurement in Early Clinical Sepsis-Can You Catch a Shadow? Crit Care Med 2019; 46:1028-1030. [PMID: 29762410 DOI: 10.1097/ccm.0000000000003108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Russ M, Ott S, Bedarf JR, Kirschfink M, Hiebl B, Unger JK. Increased compensatory kidney workload results in cellular damage in a short time porcine model of mixed acidemia - Is acidemia a 'first hit' in acute kidney injury? PLoS One 2019; 14:e0218308. [PMID: 31206554 PMCID: PMC6576776 DOI: 10.1371/journal.pone.0218308] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Accepted: 05/30/2019] [Indexed: 12/20/2022] Open
Abstract
Acute kidney injury (AKI) corrupts the outcome of about 50% of all critically ill patients. We investigated the possible contribution of the pathology acidemia on the development of AKI. Pigs were exposed to acidemia, acidemia plus hypoxemia or a normal acid-base balance in an experimental setup, which included mechanical ventilation and renal replacement therapy to facilitate biotrauma caused by extracorporeal therapies. Interestingly, extensive histomorphological changes like a tubular loss of cell barriers occurred in the kidneys after just 5 hours exposure to acidemia. The additional exposure to hypoxemia aggravated these findings. These ‘early’ microscopic pathologies opposed intra vitam data of kidney function. They did not mirror cellular or systemic patterns of proinflammatory molecules (like TNF-α or IL 18) nor were they detectable by new, sensitive markers of AKI like Neutrophil gelatinase-associated lipocalin. Instead, the data suggest that the increased renal proton excretion during acidemia could be an ‘early’ first hit in the multifactorial pathogenesis of AKI.
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Affiliation(s)
- Martin Russ
- Department of Anesthesiology and Operative Intensive Care Medicine, Campus Virchow-Klinikum and Campus Charité Mitte, Charité–Universitätsmedizin Berlin, Berlin, Germany
- * E-mail:
| | - Sascha Ott
- Department of Experimental Medicine, Campus Virchow-Klinikum, Charité–Universitätsmedizin Berlin, Berlin, Germany
| | - Janis R. Bedarf
- Department of Neurology, University of Bonn, Bonn, Germany
- German Centre for Neurodegenerative Disease Research (DZNE), Bonn, Germany
| | - Michael Kirschfink
- Institute for Clinical Immunology, University Hospital Heidelberg, Heidelberg, Germany
| | - Bernhard Hiebl
- Institute for Animal Hygiene, Animal Welfare and Farm Animal Behaviour and Virtual Center for Replacement–Complementary Methods to Animal Testing, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Juliane K. Unger
- Department of Experimental Medicine, Campus Virchow-Klinikum, Charité–Universitätsmedizin Berlin, Berlin, Germany
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Biochemical Markers of Renal Hypoperfusion, Hemoconcentration, and Proteinuria after Extreme Physical Exercise. ACTA ACUST UNITED AC 2019; 55:medicina55050154. [PMID: 31108972 PMCID: PMC6571854 DOI: 10.3390/medicina55050154] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 04/18/2019] [Accepted: 05/15/2019] [Indexed: 11/17/2022]
Abstract
Background and Objectives: Physical exercise increases the blood perfusion of muscles, but decreases the renal blood flow. There are several markers of renal hypoperfusion which are used in the differential diagnosis of acute kidney failure. Albuminuria is observed after almost any exercise. The aim of this study was to assess changes in renal hypoperfusion and albuminuria after a 100-km race. Materials and Methods: A total of 27 males who finished a 100-km run were studied. The mean age of the runners was 38.04 ± 5.64 years. The exclusion criteria were a history of kidney disease, glomerular filtration rate (GFR) <60 ml/min, and proteinuria. Blood and urine were collected before and after the race. The urinary albumin/creatinine ratio (ACR), fractional excretion of urea (FeUrea) and sodium (FeNa), plasma urea/creatinine ratio (sUrea/Cr), urine/plasma creatinine ratio (u/pCr), urinary sodium to potassium ratio (uNa/K), and urinary potassium to urinary potassium plus sodium ratio (uK/(K+Na)) were calculated. Results: After the race, significant changes in albuminuria and markers of renal hypoperfusion (FeNa, FeUrea, sUrea/Cr, u/sCr, urinary Na, uNa/K, uK/(K+Na)) were found. Fifteen runners (55.56%) had severe renal hypoperfusion (FeUrea <35, uNa/K <1, and uK/(Na+K) >0.5) after the race. The mean ACR increased from 6.28 ± 3.84 mg/g to 48.43 ± 51.64 mg/g (p < 0.001). The ACR was higher in the group with severe renal hypoperfusion (59.42 ± 59.86 vs. 34.68 ± 37.04 mg/g), but without statistical significance. Conclusions: More than 50% of the runners had severe renal hypoperfusion after extreme exercise. Changes in renal hemodynamics are probably an important, but not the only, factor of post-exercise proteinuria.
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Abstract
Perioperative acute kidney injury is associated with morbidity and mortality. Several definitions have been proposed, incorporating small changes of serum creatinine and urinary output reduction as diagnostic criteria. In the surgical patient, comorbidities, type and timing of surgery, and nephrotoxins are important. Patient comorbidities remain a significant risk factor. Urgent or emergent surgery and cardiac or transplantation procedures are associated with a higher risk of acute kidney injury. Nephrotoxic drugs, contrast dye, and diuretics worsen preexisting kidney dysfunction or act as an adjunctive insult to perioperative injury. This review includes preoperative, intraoperative, and postoperative issues that can be mitigated.
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Affiliation(s)
- Sheela Pai Cole
- Anesthesiology, Perioperative and Pain Medicine, Stanford University, 300 Pasteur Dr, H3580, Stanford, CA 94305, USA.
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Street JM, Koritzinsky EH, Bellomo TR, Hu X, Yuen PST, Star RA. The role of adenosine 1a receptor signaling on GFR early after the induction of sepsis. Am J Physiol Renal Physiol 2018; 314:F788-F797. [PMID: 29117994 PMCID: PMC6031909 DOI: 10.1152/ajprenal.00051.2017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 10/23/2017] [Accepted: 11/06/2017] [Indexed: 01/12/2023] Open
Abstract
Sepsis and acute kidney injury (AKI) synergistically increase morbidity and mortality in the ICU. How sepsis reduces glomerular filtration rate (GFR) and causes AKI is poorly understood; one proposed mechanism includes tubuloglomerular feedback (TGF). When sodium reabsorption by the proximal tubules is reduced in normal animals, the macula densa senses increased luminal sodium chloride, and then adenosine-1a receptor (A1aR) signaling triggers tubuloglomerular feedback, reducing GFR through afferent arteriole vasoconstriction. We measured GFR and systemic hemodynamics early during cecal ligation and puncture-induced sepsis in wild-type and A1aR-knockout mice. A miniaturized fluorometer was attached to the back of each mouse and recorded the clearance of FITC-sinistrin via transcutaneous fluorescence to monitor GFR. Clinical organ injury markers and cytokines were measured and hemodynamics monitored using implantable transducer telemetry devices. In wild-type mice, GFR was stable within 1 h after surgery, declined by 43% in the next hour, and then fell to less than 10% of baseline after 2 h and 45 min. In contrast, in A1aR-knockout mice GFR was 37% below baseline immediately after surgery and then gradually declined over 4 h. A1aR-knockout mice had similar organ injury and inflammatory responses, albeit with lower heart rate. We conclude that transcutaneous fluorescence can accurately monitor GFR and detect changes rapidly during sepsis. Tubuloglomerular feedback plays a complex role in sepsis; initially, TGF helps maintain GFR in the 1st hour, and over the subsequent 3 h, TGF causes GFR to plummet. By 18 h, TGF has no cumulative effect on renal or extrarenal organ damage.
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Affiliation(s)
- Jonathan M Street
- Renal Diagnostics and Therapeutics Unit, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland
| | - Erik H Koritzinsky
- Renal Diagnostics and Therapeutics Unit, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland
| | - Tiffany R Bellomo
- Renal Diagnostics and Therapeutics Unit, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland
| | - Xuzhen Hu
- Renal Diagnostics and Therapeutics Unit, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland
| | - Peter S T Yuen
- Renal Diagnostics and Therapeutics Unit, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland
| | - Robert A Star
- Renal Diagnostics and Therapeutics Unit, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland
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Roberts DA, Shaw AD. Impact of volume status and volume therapy on the kidney. Best Pract Res Clin Anaesthesiol 2017; 31:345-352. [PMID: 29248141 DOI: 10.1016/j.bpa.2017.08.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 08/17/2017] [Indexed: 10/19/2022]
Abstract
Volume resuscitation to correct hypotension in surgical and critically ill patients is a common practice. Available evidence suggests that iatrogenic volume overload is associated with worse outcomes in established acute kidney injury. Intraoperative arterial hypotension is associated with postoperative renal dysfunction, and prompt correction with fluid management protocols that combine inotrope infusions with volume therapy targeted to indices of volume responsiveness should be considered. From the perspective of renal function, the minimum amount of intravenous fluid required to maintain perfusion and oxygen delivery is desirable. Available evidence and expert opinion suggest that balanced crystalloid solutions are preferable to isotonic saline for volume resuscitation. Moreover, albumin has a similar safety profile as crystalloids. Hetastarch-containing colloids have a clear association with acute kidney injury.
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Affiliation(s)
- David A Roberts
- Vanderbilt University Medical Center, 1211 Medical Center Drive, 2301 VUH C/o Robin Snyder, USA; Department of Anesthesiology, Vanderbilt University Medical Center, USA.
| | - Andrew D Shaw
- Vanderbilt University Medical Center, 1211 Medical Center Drive, 2301 VUH C/o Robin Snyder, USA; Department of Anesthesiology, Vanderbilt University Medical Center, USA.
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15
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Fluid management in acute kidney injury. Intensive Care Med 2017; 43:807-815. [DOI: 10.1007/s00134-017-4817-x] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 04/22/2017] [Indexed: 12/17/2022]
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Anderberg SB, Luther T, Frithiof R. Physiological aspects of Toll-like receptor 4 activation in sepsis-induced acute kidney injury. Acta Physiol (Oxf) 2017; 219:573-588. [PMID: 27602552 PMCID: PMC5324638 DOI: 10.1111/apha.12798] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 04/08/2016] [Accepted: 09/05/2016] [Indexed: 12/21/2022]
Abstract
Sepsis‐induced acute kidney injury (SI‐AKI) is common and associated with high mortality. Survivors are at increased risk of chronic kidney disease. The precise mechanism underlying SI‐AKI is unknown, and no curative treatment exists. Toll‐like receptor 4 (TLR4) activates the innate immune system in response to exogenous microbial products. The result is an inflammatory reaction aimed at clearing a potential infection. However, the consequence may also be organ dysfunction as the immune response can cause collateral damage to host tissue. The purpose of this review is to describe the basis for how ligand binding to TLR4 has the potential to cause renal dysfunction and the mechanisms by which this may take place in gram‐negative sepsis. In addition, we highlight areas for future research that can further our knowledge of the pathogenesis of SI‐AKI in relation to TLR4 activation. TLR4 is expressed in the kidney. Activation of TLR4 causes cytokine and chemokine release as well as renal leucocyte infiltration. It also results in endothelial and tubular dysfunction in addition to altered renal metabolism and circulation. From a physiological standpoint, inhibiting TLR4 in large animal experimental SI‐AKI significantly improves renal function. Thus, current evidence indicates that TLR4 has the ability to mediate SI‐AKI by a number of mechanisms. The strong experimental evidence supporting a role of TLR4 in the pathogenesis of SI‐AKI in combination with the availability of pharmacological tools to target TLR4 warrants future human studies.
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Affiliation(s)
- S. B. Anderberg
- Department of Surgical Sciences; Section of Anesthesia & Intensive Care; Uppsala University; Uppsala Sweden
| | - T. Luther
- Department of Surgical Sciences; Section of Anesthesia & Intensive Care; Uppsala University; Uppsala Sweden
| | - R. Frithiof
- Department of Surgical Sciences; Section of Anesthesia & Intensive Care; Uppsala University; Uppsala Sweden
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Wang L, Song J, Buggs J, Wei J, Wang S, Zhang J, Zhang G, Lu Y, Yip KP, Liu R. A new mouse model of hemorrhagic shock-induced acute kidney injury. Am J Physiol Renal Physiol 2016; 312:F134-F142. [PMID: 28042109 DOI: 10.1152/ajprenal.00347.2016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 10/25/2016] [Accepted: 10/31/2016] [Indexed: 11/22/2022] Open
Abstract
Current animal models of hemorrhagic shock-induced acute kidney injury (HS-induced AKI) require extensive surgical procedures and constant monitoring of hemodynamic parameters. Application of these HS-induced AKI models in mice to produce consistent kidney injury is challenging. In the present study, we developed a simple and highly reproducible mouse model of HS-induced AKI by combining moderate bleeding and renal pedicle clamping, which was abbreviated as HS-AKI. HS was induced by retroorbital bleeding of 0.4 ml blood in C57BL/6 mice. Mice were left in HS stage for 30 min, followed by renal pedicle clamping for 18 min at 36.8-37.0°C. Mean arterial pressure (MAP) and heart rate were monitored with preimplanted radio transmitters throughout the experiment. The acute response in renal blood flow (RBF) triggered by HS was measured with transonic flow probe. Mice received sham operation; bleeding alone and renal pedicle clamping alone served as respective controls. MAP was reduced from 77 ± 4 to 35 ± 3 mmHg after bleeding. RBF was reduced by 65% in the HS period. Plasma creatinine and kidney injury molecule-1 levels were increased by more than 22-fold 24 h after reperfusion. GFR was declined by 78% of baseline 3 days after reperfusion. Histological examination revealed a moderate-to-severe acute tubular damage, mostly at the cortex-medulla junction area, followed by the medullar and cortex regions. HS alone did not induce significant kidney injury, but synergistically enhanced pedicle clamping-induced AKI. This is a well-controlled, simple, and reliable mouse model of HS-AKI.
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Affiliation(s)
- Lei Wang
- Department of Molecular Pharmacology & Physiology, University of South Florida College of Medicine, Tampa, Florida;
| | - Jiangping Song
- Department of Molecular Pharmacology & Physiology, University of South Florida College of Medicine, Tampa, Florida
| | | | - Jin Wei
- Department of Molecular Pharmacology & Physiology, University of South Florida College of Medicine, Tampa, Florida
| | - Shaohui Wang
- Department of Molecular Pharmacology & Physiology, University of South Florida College of Medicine, Tampa, Florida
| | - Jie Zhang
- Department of Molecular Pharmacology & Physiology, University of South Florida College of Medicine, Tampa, Florida
| | - Gensheng Zhang
- Department of Molecular Pharmacology & Physiology, University of South Florida College of Medicine, Tampa, Florida.,Department of Physiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Yan Lu
- Department of Medicine, University of Mississippi Medical Center, Jackson, Mississippi; and
| | - Kay-Pong Yip
- Department of Molecular Pharmacology & Physiology, University of South Florida College of Medicine, Tampa, Florida
| | - Ruisheng Liu
- Department of Molecular Pharmacology & Physiology, University of South Florida College of Medicine, Tampa, Florida
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Koza Y. Acute kidney injury: current concepts and new insights. J Inj Violence Res 2016; 8:58-62. [PMID: 26804946 PMCID: PMC4729334 DOI: 10.5249/jivr.v8i1.610] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 07/10/2014] [Indexed: 12/21/2022] Open
Abstract
Background: Acute kidney injury, which was previously named as acute renal failure, is a complex clinical disorder and continues to be associated with poor outcomes. It is frequently seen in hospitalized patients, especially in critically ill patients. The primary causes of acute kidney injury are divided into three categories: prerenal, intrinsic renal and postrenal. The definition and staging of acute kidney injury are mainly based on the risk, injury, failure, loss, end-stage kidney disease (RIFLE) criteria and the acute kidney injury network (AKIN) criteria, which have previously been defined. However the clinical utility of these criteria is still uncertain. Several biomarkers such as Cystatin C and neutrophil gelatinase-associated lipocalin have been suggested for the diagnosis, severity classification and most importantly, the modification of outcome in acute kidney injury. Methods: Current literature on the definition, biomarkers, management and epidemiology of acute kidney injury was reviewed by searching keywords in Medline and PubMed databases. Results: The epidemiology, pathophysiology and diagnosis of acute kidney injury were discussed. The clinical implications of novel biomarkers and management of acute kidney injury were also discussed. Conclusions: The current definitions of acute kidney injury are based on the RIFLE, AKIN and KDIGO criteria. Although these criteria have been widely validated, some of limitations are still remain. Since acute kidney injury is common and harmful, all preventive measures should be taken to avoid its occurrence. Currently, there is no a definitive role for novel biomarkers.
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Affiliation(s)
- Yavuzer Koza
- Department of Cardiology, Ataturk University Faculty of Medicine, Erzurum, Turkey. E-mail:
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Urinary Output Predicts Survival in Patients Undergoing Extracorporeal Membrane Oxygenation Following Cardiovascular Surgery. Crit Care Med 2016; 44:531-8. [PMID: 26562346 DOI: 10.1097/ccm.0000000000001421] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Extracorporeal membrane oxygenation represents a valuable and rapidly evolving therapeutic option in patients with severe heart or lung failure following cardiovascular surgery. However, survival remains poor and accurate risk stratification challenging. Therefore, we evaluated the predictive value of urinary output within 24 hours after extracorporeal membrane oxygenation initiation on mortality in patients undergoing venoarterial extracorporeal membrane oxygenation support following cardiovascular surgery and aimed to improve established risk prediction models. DESIGN Single-center, observational registry. SETTING University-affiliated tertiary care center. PATIENTS We included 205 patients undergoing veno-arterial extracorporeal membrane oxygenation therapy following cardiovascular surgery at a university-affiliated tertiary-care center into our single-centre registry. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS During a median follow-up time of 35 months (interquartile range, 19-69), 64% of patients died. Twenty-four-hour urinary output was the strongest predictor of outcome among renal function variables with an adjusted hazard ratio per 1 SD of 0.55 (95% CI, 0.40-0.76; p < 0.001) for 30-day mortality and of 0.65 (95% CI, 0.53-0.86; p = 0.002) for 2-year long-term mortality. Most remarkably, 24-hour urinary output showed additional prognostic value beyond that achievable with the simplified acute physiology score-3 and sequential organ failure assessment score indicated by improvements in the category-free net reclassification index for 30-day mortality (simplified acute physiology score-3: 36%, p = 0.015; sequential organ failure assessment score: 36%, p = 0.02), as well as for 2-year mortality (simplified acute physiology score-3: 33%, p = 0.02; sequential organ failure assessment score: 43%, p = 0.005). CONCLUSIONS We identified 24-hour urinary output as a strong and easily available predictor of mortality in patients undergoing extracorporeal membrane oxygenation therapy following cardiovascular surgery. Implementation of 24-hour urinary output leads to a substantial improvement of established risk prediction models in this vulnerable patient population. These results are particularly compelling because measurement of urinary output is inexpensive and routinely performed in all critical care units.
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Prowle JR, Bellomo R. Sepsis-associated acute kidney injury: macrohemodynamic and microhemodynamic alterations in the renal circulation. Semin Nephrol 2015; 35:64-74. [PMID: 25795500 DOI: 10.1016/j.semnephrol.2015.01.007] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Traditionally, renal ischemia has been regarded as central to the pathogenesis of sepsis-associated acute kidney injury (SA-AKI). Accordingly, hemodynamic management of SA-AKI has emphasized restoration of renal perfusion, whereas, experimentally, ischemia reperfusion models have been emphasized. However, in human beings, SA-AKI usually is accompanied by hyperdynamic circulation. Moreover, clinical and experimental evidence now suggests the importance of inflammatory mechanisms in the development of AKI and microcirculatory dysfunction more than systemic alteration in renal perfusion. In this review, we examine systemic, regional, and microcirculatory hemodynamics in SA-AKI, and attempt to rationalize the hemodynamic management of this condition.
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Affiliation(s)
- John R Prowle
- Adult Critical Care Unit, Department of Renal Medicine and Transplantation, The Royal London Hospital, Barts Health NHS Trust, London, UK; William Harvey Research Institute, Queen Mary University of London, London, UK
| | - Rinaldo Bellomo
- Department of Intensive Care, Austin Hospital, Melbourne, Australia; Australian and New Zealand Intensive Care Research Centre, Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia.
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Okusa MD, Rosner MH, Kellum JA, Ronco C. Therapeutic Targets of Human AKI: Harmonizing Human and Animal AKI. J Am Soc Nephrol 2015; 27:44-8. [PMID: 26519086 DOI: 10.1681/asn.2015030233] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The opportunity to make advances in the prevention and treatment of AKI has never been greater than it is today. Major advances have been made in the understanding of the biology of AKI, the design of clinical trials, and the use of diagnostic and prognostic biomarkers. These advances have been supplemented by the coordinated effort of societies, federal agencies, and industry, such that we are poised in the ensuing years to positively address the unrelenting harm that this disorder has created. Over the past decade, major advances have been made in understanding the pathophysiology of AKI, mainly through the study of small animal models. However, translating these findings to human AKI remains a barrier, which is typified by the absence of effective therapeutic agents. The purpose of the Acute Dialysis Quality Initiative (ADQI) XIII was to harmonize human and animal studies and determine what is known about potential therapeutic targets and what gaps in knowledge remain. A series of invited reviews will distill key concepts from this initiative that focus on different pathogenic features of AKI, including hemodynamics, immunity and inflammation, cellular and molecular pathways, progression, and regeneration and repair. This series will convey the status of our knowledge of the pathophysiology of human AKI and propose therapeutic targets for further investigation.
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Affiliation(s)
- Mark D Okusa
- Division of Nephrology, Center for Immunity, Inflammation and Regenerative Medicine, University of Virginia Health System, Charlottesville, Virginia;
| | - Mitchell H Rosner
- Division of Nephrology, Center for Immunity, Inflammation and Regenerative Medicine, University of Virginia Health System, Charlottesville, Virginia
| | - John A Kellum
- Center for Critical Care Nephrology and Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania; and
| | - Claudio Ronco
- Department of Nephrology Dialysis and Transplantation, San Bortolo Hospital and the International Renal Research Institute, Vicenza, Italy
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22
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Matejovic M, Ince C, Chawla LS, Blantz R, Molitoris BA, Rosner MH, Okusa MD, Kellum JA, Ronco C. Renal Hemodynamics in AKI: In Search of New Treatment Targets. J Am Soc Nephrol 2015; 27:49-58. [PMID: 26510884 DOI: 10.1681/asn.2015030234] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Novel therapeutic interventions are required to prevent or treat AKI. To expedite progress in this regard, a consensus conference held by the Acute Dialysis Quality Initiative was convened in April of 2014 to develop recommendations for research priorities and future directions. Here, we highlight the concepts related to renal hemodynamics in AKI that are likely to reveal new treatment targets on investigation. Overall, we must better understand the interactions between systemic, total renal, and glomerular hemodynamics, including the role of tubuloglomerular feedback. Furthermore, the net consequences of therapeutic maneuvers aimed at restoring glomerular filtration need to be examined in relation to the nature, magnitude, and duration of the insult. Additionally, microvascular blood flow heterogeneity in AKI is now recognized as a common occurrence; timely interventions to preserve the renal microcirculatory flow may interrupt the downward spiral of injury toward progressive kidney failure and should, therefore, be investigated. Finally, development of techniques that permit an integrative physiologic approach, including direct visualization of renal microvasculature and measurement of oxygen kinetics and mitochondrial function in intact tissue in all nephron segments, may provide new insights into how the kidney responds to various injurious stimuli and allow evaluation of new therapeutic strategies.
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Affiliation(s)
- Martin Matejovic
- First Medical Department and Biomedical Centre, Faculty of Medicine in Plzen, Charles University in Prague, Teaching Hospital in Plzen, Plzen, Czech Republic
| | - Can Ince
- Department of Intensive Care, Erasmus Medical Center University Hospital, Rotterdam, The Netherlands
| | - Lakhmir S Chawla
- Department of Medicine, Division of Intensive Care Medicine and Division of Nephrology, Veterans Affairs Medical Center, Washington, DC
| | - Roland Blantz
- Nephrology-Hypertension Division, University of California, San Diego School of Medicine and Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Bruce A Molitoris
- Department of Medicine, Division of Nephrology and Department of Cellular and Integrative Physiology, Indiana University School of Medicine and the Rouderbush Veterans Affairs Medical Center, Indianapolis, Indiana
| | - Mitchell H Rosner
- Division of Nephrology, Center for Immunity, Inflammation and Regenerative Medicine, University of Virginia Health System, Charlottesville, Virginia;
| | - Mark D Okusa
- Division of Nephrology, Center for Immunity, Inflammation and Regenerative Medicine, University of Virginia Health System, Charlottesville, Virginia
| | - John A Kellum
- Center for Critical Care Nephrology and Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania; and
| | - Claudio Ronco
- Department of Nephrology Dialysis and Transplantation, San Bortolo Hospital and the International Renal Research Institute, Vicenza, Italy
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23
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Zhang L, Chen Z, Diao Y, Yang Y, Fu P. Associations of fluid overload with mortality and kidney recovery in patients with acute kidney injury: A systematic review and meta-analysis. J Crit Care 2015; 30:860.e7-13. [PMID: 25979272 DOI: 10.1016/j.jcrc.2015.03.025] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Revised: 03/30/2015] [Accepted: 03/31/2015] [Indexed: 02/05/2023]
Abstract
PURPOSE Fluid resuscitation is commonly administered to maintain adequate renal perfusion in critically ill patients to prevent or even treat acute kidney injury (AKI). However, recent studies show that fluid overload is common and might be associated with poor outcomes in patients with AKI. Hence, the objective of this study was to assess the associations of fluid overload with mortality and kidney recovery in patients with AKI. MATERIALS AND METHODS We electronically searched original articles published in peer-reviewed journals from their inception to January 2015 in PubMed, EMBASE, the Cochrane Library databases, Google Scholar, and Chinese database (SinoMed). We additionally searched the reference lists of all retrieved articles. We performed a systematic review and meta-analysis of all eligible cohort or case-control studies of fluid overload in patients with AKI. The primary outcomes were mortality and kidney recovery. We pooled adjusted odds ratios (ORs) with 95% confidence intervals (95% CIs) by using Review Manager 5.2 (The Cochrane Collaboration, Oxford, UK). RESULTS A total of 5095 patients from 12 cohort studies published from 2008 to 2014 were included. A significant positive association was found between fluid overload and mortality in patients with AKI (OR, 2.23; 95% CI, 1.66-3.01), with similar findings in sepsis (OR, 2.27; 95% CI, 1.69-to 3.03) and nonsepsis subgroups (OR, 3.40; 95% CI, 2.50-4.63). There was also a significant association between mean fluid balance (continuous variables) and mortality (OR, 1.16; 95% CI, 1.07-1.27). Although there was a trend of lower rate of kidney recovery in the fluid overload group, there was no significant association between fluid overload and kidney recovery (OR, 0.66; 95% CI, 0.37-1.15), or dialysis dependence (OR, 0.72; 95% CI, 0.38-1.35). CONCLUSIONS Fluid overload is associated with an increased risk of mortality in patients with AKI. The evidence of the relationship between fluid overload and kidney recovery is insufficient.
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Affiliation(s)
- Ling Zhang
- Division of Nephrology, West China Hospital of Sichuan University, Sichuan, Chengdu, China
| | - Zhiwen Chen
- Division of Nephrology, West China Hospital of Sichuan University, Sichuan, Chengdu, China
| | - Yongshu Diao
- Division of Nephrology, West China Hospital of Sichuan University, Sichuan, Chengdu, China.
| | - Yingying Yang
- Division of Nephrology, West China Hospital of Sichuan University, Sichuan, Chengdu, China
| | - Ping Fu
- Division of Nephrology, West China Hospital of Sichuan University, Sichuan, Chengdu, China
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24
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Calzavacca P, May CN, Bellomo R. Glomerular haemodynamics, the renal sympathetic nervous system and sepsis-induced acute kidney injury. Nephrol Dial Transplant 2014; 29:2178-2184. [DOI: 10.1093/ndt/gfu052] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
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Schneider AG, Calzavacca P, Schelleman A, Huynh T, Bailey M, May C, Bellomo R. Contrast-enhanced ultrasound evaluation of renal microcirculation in sheep. Intensive Care Med Exp 2014; 2:33. [PMID: 26266930 PMCID: PMC4513025 DOI: 10.1186/s40635-014-0033-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 11/16/2014] [Indexed: 12/29/2022] Open
Abstract
Background Contrast-enhanced ultrasonography (CEUS) is a novel imaging modality to estimate microvascular perfusion. We aimed to assess renal cortical microcirculatory changes by CEUS during pharmacologically or mechanically induced modifications of renal blood flow (RBF) in experimental animals. Methods We implanted invasive transit-time Doppler flow probes and a vascular occluder around the renal artery in six Merino sheep. After induction of general anaesthesia, renal CEUS studies with destruction-replenishment sequences were performed at baseline and after different interventions aimed at modifying RBF. First, we administered angiotensin II (AngII) to achieve a 25% (AngII 25%) and 50% (AngII 50%) decrease in RBF. Then, we applied mechanical occlusion of the renal artery until RBF decreased by 25% (Occl 25%) and 50% (Occl 50%) of the baseline. Finally, a single dose of 25 mg of captopril was administered. CEUS sequences were analysed offline with dedicated software and perfusion indices (PI) calculated. Results Pharmacological reduction of RBF with AngII was associated with a 62% (range: 68 decrease to 167 increase) increase (AngII 25%) and a 5% increase in PI (range: 92% decrease to 53% increase) (AngII 50%) in PI. Mechanical occlusion of the renal artery was associated with a 2% (range: 43% decrease to 2% increase) decrease (Occl 25%) and a 67% (range: 63% decrease to a 120% increase) increase (Occl 50%) in PI. The administration of captopril was associated with a 8% (range: 25% decrease to a 101% increase) decrease in PI. Pooled changes in PI failed to reach statistical significance. The study was limited by the difficulty to obtain high quality images. Conclusions CEUS-derived parameters were highly heterogeneous in this sheep model. The current protocol and model did not allow the evaluation of the correlation between macro and microcirculation assessment by CEUS.
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Affiliation(s)
- Antoine G Schneider
- Intensive Care Unit, Austin Health, Austin Health, 145 Studley Road, Heidelberg, Victoria, 3084, Australia,
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26
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Abstract
PURPOSE OF REVIEW To review recent studies and information on the relationship between fluid administration and kidney function in critically ill patients. RECENT FINDINGS There is little evidence from large multicenter trials to direct fluid therapy in patients at risk of acute kidney injury (AKI). Evidence of benefit for fluid administration from single center studies of fluid resuscitation to hemodynamic goals needs to be weighed against evidence of harm associated with fluid overload in large observational studies. The composition of intravenous fluid may affect the risk of AKI. Even latest-generation hydroxyethyl starches increase the risk of severe AKI in general and septic ICU patients. Isotonic saline has been associated with greater incidence of AKI in comparison to buffered crystalloids. Experimentally, infusion of saline results in reduction in renal perfusion in comparison to buffered solutions. SUMMARY Clinicians need to weigh the balance between adequate resuscitation of cardiac output and avoidance of fluid overload. Protocolized resuscitation to hemodynamic goals may help achieve these conflicting goals at least in the early phases of critical illness. In critically ill patients with, or at risk of, AKI, clinicians should avoid starch and, possibly, saline solutions.
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27
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Prowle JR. Acute kidney injury: an intensivist's perspective. Pediatr Nephrol 2014; 29:13-21. [PMID: 23361310 DOI: 10.1007/s00467-013-2411-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 12/28/2012] [Accepted: 01/03/2013] [Indexed: 01/05/2023]
Abstract
The changing epidemiology of acute kidney injury (AKI) in adults and children has resulted in more patients being treated for kidney injury occurring in the context of multi-organ failure requiring treatment in the intensive care unit (ICU). AKI complicating critical illness has complex, multi-factorial etiology, and supportive care, including organ support, remains the mainstay of therapy. In the day-to-day management of AKI in the ICU two of the major challenges are the inadequacy of current diagnostics for the early identification of AKI and the relationship between hemodynamic resuscitation strategies and the development of AKI. This review focuses on these areas from the intensivist's perspective. Given that the diagnosis of AKI is often delayed, the prevention of complications and limitation of secondary renal injury are of particular importance. Fluid overload is increasingly being associated with adverse patient outcomes in critical illness and may contribute to persistent renal dysfunction. Thus, hemodynamic management strategies in AKI should be tailored to limit fluid overload as much as possible.
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Affiliation(s)
- John R Prowle
- Adult Critical Care Unit and Department of Renal Medicine and Transplantation, The Royal London Hospital, Barts Health NHS Trust, Whitechapel Road, London, UK, E1 1BB,
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28
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Abstract
In patients with acute kidney injury (AKI), optimization of systemic haemodynamics is central to the clinical management. However, considerable debate exists regarding the efficacy, nature, extent and duration of fluid resuscitation, particularly when the patient has undergone major surgery or is in septic shock. Crucially, volume resuscitation might be required to maintain or restore cardiac output. However, resultant fluid accumulation and tissue oedema can substantially contribute to ongoing organ dysfunction and, particularly in patients developing AKI, serious clinical consequences. In this Review, we discuss the conflict between the desire to achieve adequate resuscitation of shock and the need to mitigate the harmful effects of fluid overload. In patients with AKI, limiting and resolving fluid overload might prompt earlier use of renal replacement therapy. However, rapid or early excessive fluid removal with diuretics or extracorporeal therapy might lead to hypovolaemia and recurrent renal injury. Optimal management might involve a period of guided fluid resuscitation, followed by management of an even fluid balance and, finally, an appropriate rate of fluid removal. To obtain best clinical outcomes, serial fluid status assessment and careful definition of cardiovascular and renal targets will be required during fluid resuscitation and removal.
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Renal blood flow, fractional excretion of sodium and acute kidney injury: time for a new paradigm? Curr Opin Crit Care 2013; 18:585-92. [PMID: 22954663 DOI: 10.1097/mcc.0b013e328358d480] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
PURPOSE OF REVIEW Global renal blood flow is considered pivotal to renal function. Decreased global renal blood flow (decreased perfusion) is further considered the major mechanism of reduced glomerular filtration rate responsible for the development of acute kidney injury (AKI) in critically ill patients. Additionally, urinary biochemical tests are widely taught to allow the differential diagnosis of prerenal (functional) AKI and intrinsic [structural AKI (so-called acute tubular necrosis)]. In this review we will examine recent evidence regarding these two key clinical paradigms. RECENT FINDINGS Recent animal experiments and clinical studies in humans using cine-phase contrast magnetic resonance technology are not consistent with the decreased perfusion paradigm. They suggest instead that changes in the intra-renal circulation including modification in efferent arteriolar function and intra-renal shunting are much more likely to be responsible for AKI, especially in sepsis. Similarly, recent human studies indicate the urinary biochemistry has limited diagnostic or prognostic ability and is dissociated form biomarker and microscopic evidence of tubular injury. SUMMARY Intra-renal microcirculatory changes are likely more important than changes in global blood flow in the development of AKI. Urinary biochemistry is not a clinically useful diagnostic or prognostic tool in critically ill patients at risk of or with AKI.
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Cavaillé-Coll M, Bala S, Velidedeoglu E, Hernandez A, Archdeacon P, Gonzalez G, Neuland C, Meyer J, Albrecht R. Summary of FDA workshop on ischemia reperfusion injury in kidney transplantation. Am J Transplant 2013; 13:1134-48. [PMID: 23566221 DOI: 10.1111/ajt.12210] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 01/24/2013] [Accepted: 01/31/2013] [Indexed: 01/25/2023]
Abstract
The Food and Drug Administration (FDA) held an open public workshop in September 2011 to discuss the current state of science related to the effects of ischemia reperfusion injury (IRI) on outcomes in kidney transplantation. Topics included the development of IRI and delayed graft function (DGF), histology and biomarkers, donor factors, recipient factors, organ quality and organ preservation by means of cold storage solutions or machine perfusion. Various mechanisms of injury and maladaptive response to IRI were discussed as potential targets of intervention. Animal models evaluating specific pathophysiological pathways were presented, as were the limitations of extrapolating animal results to humans. Clinical trials of various drug products administered in the peri-transplant period were summarized; a few demonstrated early improvements in DGF, but none demonstrated an improvement in late graft function. Clinical trial design for IRI and DGF were also discussed.
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Affiliation(s)
- M Cavaillé-Coll
- Division of Transplant and Ophthalmology Products, Office of Antimicrobial Products, Office of New Drugs, Center for Drug Evaluation and Research, FDA, Silver Spring, MD, USA
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31
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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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Abstract
Acute kidney injury (formerly known as acute renal failure) is a syndrome characterised by the rapid loss of the kidney's excretory function and is typically diagnosed by the accumulation of end products of nitrogen metabolism (urea and creatinine) or decreased urine output, or both. It is the clinical manifestation of several disorders that affect the kidney acutely. Acute kidney injury is common in hospital patients and very common in critically ill patients. In these patients, it is most often secondary to extrarenal events. How such events cause acute kidney injury is controversial. No specific therapies have emerged that can attenuate acute kidney injury or expedite recovery; thus, treatment is supportive. New diagnostic techniques (eg, renal biomarkers) might help with early diagnosis. Patients are given renal replacement therapy if acute kidney injury is severe and biochemical or volume-related, or if uraemic-toxaemia-related complications are of concern. If patients survive their illness and do not have premorbid chronic kidney disease, they typically recover to dialysis independence. However, evidence suggests that patients who have had acute kidney injury are at increased risk of subsequent chronic kidney disease.
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Affiliation(s)
- Rinaldo Bellomo
- Australian and New Zealand Intensive Care Research Centre, School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia.
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Prowle JR, Chua HR, Bagshaw SM, Bellomo R. Clinical review: Volume of fluid resuscitation and the incidence of acute kidney injury - a systematic review. Crit Care 2012; 16:230. [PMID: 22866958 PMCID: PMC3580679 DOI: 10.1186/cc11345] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Intravenous fluids are widely administered to maintain renal perfusion and prevent acute kidney injury (AKI). However, fluid overload is of concern during AKI. Using the Pubmed database (up to October 2011) we identified all randomised controlled studies of goal-directed therapy (GDT)-based fluid resuscitation (FR) reporting renal outcomes and documenting fluid given during perioperative care. In 24 perioperative studies, GDT was associated with decreased risk of postoperative AKI (odds ratio (OR) = 0.59, 95% confidence interval (CI) = 0.39 to 0.89) but additional fluid given was limited (median: 555 ml). Moreover, the decrease in AKI was greatest (OR = 0.47, 95% CI = 0.29 to 0.76) in the 10 studies where FR was the same between GDT and control groups. Inotropic drug use in GDT patients was associated with decreased AKI (OR = 0.52, 95% CI = 0.34 to 0.80, P = 0.003), whereas studies not involving inotropic drugs found no effect (OR = 0.75, 95% CI = 0.37 to 1.53, P = 0.43). The greatest protection from AKI occurred in patients with no difference in total fluid delivery and use of inotropes (OR = 0.46, 95% CI = 0.27 to 0.76, P = 0.0036). GDT-based FR may decrease AKI in surgical patients; however, this effect requires little overall FR and appears most effective when supported by inotropic drugs.
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Affiliation(s)
- John R Prowle
- Adult Critical Care Unit, The Royal London Hospital, Barts Health NHS Trust, Whitechapel Road, London E1 1BB, UK
| | - Horng-Ruey Chua
- Division of Nephrology, University Medicine Cluster, National University Health System, 5 Lower Kentridge Road, Singapore 119074
| | - Sean M Bagshaw
- Division of Critical Care Medicine, Faculty of Medicine and Dentistry, University of Alberta, 3C1.12 Walter C. Mackenzie Centre, 8440-122 Street, Edmonton, AB, T6G 2B7, Canada
| | - Rinaldo Bellomo
- Department of Intensive Care, Austin Health, 145 Studley Road, Heidelberg, Victoria 3084, Australia
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Legrand M, Bezemer R, Kandil A, Demirci C, Payen D, Ince C. The role of renal hypoperfusion in development of renal microcirculatory dysfunction in endotoxemic rats. Intensive Care Med 2011; 37:1534-42. [PMID: 21695476 PMCID: PMC3155675 DOI: 10.1007/s00134-011-2267-4] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Accepted: 05/07/2011] [Indexed: 01/20/2023]
Abstract
Purpose To study the role of renal hypoperfusion in development of renal microcirculatory dysfunction in endotoxemic rats. Methods Rats were randomized into four groups: a sham group (n = 6), a lipopolysaccharide (LPS) group (n = 6), a group in which LPS administration was followed by immediate fluid resuscitation which prevented the drop of renal blood flow (EARLY group) (n = 6), and a group in which LPS administration was followed by delayed (i.e., a 2-h delay) fluid resuscitation (LATE group) (n = 6). Renal blood flow was measured using a transit-time ultrasound flow probe. Microvascular perfusion and oxygenation distributions in the renal cortex were assessed using laser speckle imaging and phosphorimetry, respectively. Interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-α were measured as markers of systemic inflammation. Furthermore, renal tissue samples were stained for leukocyte infiltration and inducible nitric oxide synthase (iNOS) expression in the kidney. Results LPS infusion worsened both microvascular perfusion and oxygenation distributions. Fluid resuscitation improved perfusion histograms but not oxygenation histograms. Improvement of microvascular perfusion was more pronounced in the EARLY group compared with the LATE group. Serum cytokine levels decreased in the resuscitated groups, with no difference between the EARLY and LATE groups. However, iNOS expression and leukocyte infiltration in glomeruli were lower in the EARLY group compared with the LATE group. Conclusions In our model, prevention of endotoxemia-induced systemic hypotension by immediate fluid resuscitation (EARLY group) did not prevent systemic inflammatory activation (IL-6, IL-10, TNF-α) but did reduce renal inflammation (iNOS expression and glomerular leukocyte infiltration). However, it could not prevent reduced renal microvascular oxygenation. Electronic supplementary material The online version of this article (doi:10.1007/s00134-011-2267-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Matthieu Legrand
- Department of Translational Physiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.
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Legrand M, Payen D. Understanding urine output in critically ill patients. Ann Intensive Care 2011; 1:13. [PMID: 21906341 PMCID: PMC3224471 DOI: 10.1186/2110-5820-1-13] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Accepted: 05/24/2011] [Indexed: 02/06/2023] Open
Abstract
Urine output often is used as a marker of acute kidney injury but also to guide fluid resuscitation in critically ill patients. Although decrease of urine output may be associated to a decrease of glomerular filtration rate due to decrease of renal blood flow or renal perfusion pressure, neurohormonal factors and functional changes may influence diuresis and natriuresis in critically ill patients. The purpose of this review is to discuss the mechanisms of diuresis regulation, which may help to interpret the urine output in critically ill patients and the appropriate treatment to be initiated in case of changes in urine output.
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Affiliation(s)
- Matthieu Legrand
- Department of Anesthesiology and Critical Care and SAMU, Lariboisière Hospital, Assistance Publique- Hopitaux de Paris; University of Paris 7 Denis Diderot, 2 rue Ambroise-Paré, 75475 Paris Cedex 10, France.
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Abstract
PURPOSE OF REVIEW Intravenous fluids are widely administered in the ICU with the intention of preventing or ameliorating acute kidney injury (AKI). This review focuses on recent studies examining fluid administration and renal function in critical illness to critically examine conventional justifications for fluid administration. RECENT FINDINGS Early, targeted, resuscitation of inadequate cardiac output in shock may have a beneficial effect on organ function and patient outcome. However, experimental evidence suggests the relationship between fluid administration and an increase in renal oxygen delivery is weak, whereas any beneficial effects from fluid administration can be short lived. Conversely, evidence associating fluid overload and adverse outcomes is strengthening, whereas more restrictive fluid administration does not seem to predispose to clinically significant AKI in many situations. Furthermore, concerns persist that some colloid or high chloride concentration solutions may directly impair renal function independent of volume overload. SUMMARY Adequate volume resuscitation remains a cornerstone to the emergent treatment of critical illness. However, continued fluid administration and positive fluid balances have not been shown to improve renal outcomes and may worsen overall prognosis in AKI. Concerns about renal dysfunction should not deter clinicians from adopting more restrictive approaches to fluid administration.
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Affiliation(s)
- John R Prowle
- Department of Intensive Care, Austin Health, Heidelberg, Victoria, Australia
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Antonelli M, Azoulay E, Bonten M, Chastre J, Citerio G, Conti G, De Backer D, Gerlach H, Hedenstierna G, Joannidis M, Macrae D, Mancebo J, Maggiore SM, Mebazaa A, Preiser JC, Pugin J, Wernerman J, Zhang H. Year in review in Intensive Care Medicine 2010: I. Acute renal failure, outcome, risk assessment and ICU performance, sepsis, neuro intensive care and experimentals. Intensive Care Med 2011; 37:19-34. [PMID: 21203748 PMCID: PMC3029817 DOI: 10.1007/s00134-010-2112-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Accepted: 12/03/2010] [Indexed: 12/18/2022]
Affiliation(s)
- Massimo Antonelli
- Department of Intensive Care and Anesthesiology, Policlinico Universitario A. Gemelli, Università Cattolica del Sacro Cuore, Largo A. Gemelli, 8, 00168 Rome, Italy.
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Groesdonk HV, Heringlake M. The kidney in acute renal failure: innocent bystander, victim or still a suspect? Intensive Care Med 2010; 36:389-91. [PMID: 20049586 DOI: 10.1007/s00134-009-1741-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Accepted: 11/19/2009] [Indexed: 11/24/2022]
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