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Al-Beltagi M, Saeed NK, Bediwy AS, Elbeltagi R. Pulse oximetry in pediatric care: Balancing advantages and limitations. World J Clin Pediatr 2024; 13:96950. [PMID: 39350904 PMCID: PMC11438930 DOI: 10.5409/wjcp.v13.i3.96950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2024] [Revised: 07/06/2024] [Accepted: 07/30/2024] [Indexed: 08/30/2024] Open
Abstract
BACKGROUND Pulse oximetry has become a cornerstone technology in healthcare, providing non-invasive monitoring of oxygen saturation levels and pulse rate. Despite its widespread use, the technology has inherent limitations and challenges that must be addressed to ensure accurate and reliable patient care. AIM To comprehensively evaluate the advantages, limitations, and challenges of pulse oximetry in clinical practice, as well as to propose recommendations for optimizing its use. METHODS A systematic literature review was conducted to identify studies related to pulse oximetry and its applications in various clinical settings. Relevant articles were selected based on predefined inclusion and exclusion criteria, and data were synthesized to provide a comprehensive overview of the topic. RESULTS Pulse oximetry offers numerous advantages, including non-invasiveness, real-time feedback, portability, and cost-effectiveness. However, several limitations and challenges were identified, including motion artifacts, poor peripheral perfusion, ambient light interference, and patient-specific factors such as skin pigmentation and hemoglobin variants. Recommendations for optimizing pulse oximetry use include technological advancements, education and training initiatives, quality assurance protocols, and interdisciplinary collaboration. CONCLUSION Pulse oximetry is crucial in modern healthcare, offering invaluable insights into patients' oxygenation status. Despite its limitations, pulse oximetry remains an indispensable tool for monitoring patients in diverse clinical settings. By implementing the recommendations outlined in this review, healthcare providers can enhance the effectiveness, accessibility, and safety of pulse oximetry monitoring, ultimately improving patient outcomes and quality of care.
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Affiliation(s)
- Mohammed Al-Beltagi
- Department of Pediatric, Faculty of Medicine, Tanta University, Tanta 31511, Alghrabia, Egypt
- Department of Pediatrics, University Medical Center, King Abdulla Medical City, Arabian Gulf University, Manama 26671, Manama, Bahrain
| | - Nermin Kamal Saeed
- Medical Microbiology Section, Department of Pathology, Salmaniya Medical Complex, Ministry of Health, Kingdom of Bahrain, Manama 26671, Manama, Bahrain
- Medical Microbiology Section, Department of Pathology, Irish Royal College of Surgeon in Bahrain, Busaiteen 15503, Muharraq, Bahrain
| | - Adel Salah Bediwy
- Department of Pulmonology, Faculty of Medicine, Tanta University, Tanta 31527, Alghrabia, Egypt
- Department of Pulmonology, University Medical Center, King Abdulla Medical City, Arabian Gulf University, Manama 26671, Manama, Bahrain
| | - Reem Elbeltagi
- Department of Medicine, The Royal College of Surgeons in Ireland-Bahrain, Busiateen 15503, Muharraq, Bahrain
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Pastacı Özsobacı N, Karış D, Ercan AM, Özçelik D. Investigation of Zinc on hemorheological parameters in a rat model of diabetes. J Trace Elem Med Biol 2024; 84:127450. [PMID: 38643593 DOI: 10.1016/j.jtemb.2024.127450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 04/01/2024] [Accepted: 04/09/2024] [Indexed: 04/23/2024]
Abstract
Diabetes mellitus (DM) is a complex, chronic metabolic disorder characterized by impaired regulation of blood glucose levels. Zinc (Zn) is an essential trace elements that plays a role in various physiological processes within the body, including those related to diabetes. The current study was investigated the effect of Zn supplementation on hemorheological parameters in a rat model of DM. After induction of DM, 32 male Wistar albino rats were divided into four groups: control, Zn, DM, and Zn+DM. Whole blood viscosity (WBV) was determined by using digital cone and plate viscometer and plasma viscosity (PV) was determined by a Coulter Harkness capillary viscometer. The rats in the DM Group showed a decrease in both Zn levels and body weight, as well as an increase in glucose levels when compared to the control group. Diabetic rats supplemented with Zn displayed lower blood glucose levels and higher concentrations of Zn compared to the DM Group. The higher PV and lower hematocrit level were measured in DM Group than control group and lower PV, higher hematocrit level were measured in Zn+DM group than DM Group. The WBV was measured at four different shear rates (57.6-115.2 - 172.8-230.4 s -1). A statistically significant increase was observed in the DM group compared to the control group. Additionally, a statistically significant decrease was observed in the Zn+DM Group compared to the DM Group at a shear rate of 230.4 s-1. Erythrocyte rigidity index (Tk) and oxygen delivery index (ODI) were computed under conditions of high shear rate. The rats in the DM group exhibited a reduction in ODI and an elevation in Tk in comparison to the control group. Conversely, the diabetic rats supplemented with Zn exhibited decreased Tk and increased ODI compared to the DM Group. Zn supplementation seems to have a potential beneficial effect for protecting adverse affect of diabetes on hemorheogical parameters and for maintaining vascular health.
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Affiliation(s)
- Nural Pastacı Özsobacı
- Department of Biophysics, Cerrahpasa Faculty of Medicine, Istanbul University-Cerrahpasa, Istanbul, Turkiye.
| | - Denizhan Karış
- Department of Biophysics, Faculty of Medicine, Istinye University, Istanbul, Turkiye
| | - Alev Meltem Ercan
- Department of Biophysics, Cerrahpasa Faculty of Medicine, Istanbul University-Cerrahpasa, Istanbul, Turkiye
| | - Derviş Özçelik
- Department of Biophysics, Cerrahpasa Faculty of Medicine, Istanbul University-Cerrahpasa, Istanbul, Turkiye; Department of Biophysics, Faculty of Medicine, Istanbul Arel University, Istanbul, Turkiye
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3
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Lim BJ, Shin JY, Roh SG, Lee NH, Chung YK. Clinical analysis of factors affecting the failure of free flaps used in head and neck reconstruction. Arch Craniofac Surg 2023; 24:159-166. [PMID: 37654235 PMCID: PMC10475704 DOI: 10.7181/acfs.2023.00325] [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: 06/26/2023] [Revised: 07/25/2023] [Accepted: 08/18/2023] [Indexed: 09/02/2023] Open
Abstract
BACKGROUND Free tissue transfer is the preferred method of reconstructing head and neck defects, with a success rate of approximately 95%. Although flap failure is uncommon, it has a major impact on patient morbidity and diminishes quality of life, making it is important to investigate the causes of flap failure. METHODS This retrospective chart review analyzed patients who underwent free tissue transfer during head and neck reconstruction at a single institution between 2016 and 2021. RESULTS During the study period, 58 patients underwent 60 free flap procedures. Revision surgery was needed in 14 patients. Subsequent free flap surgery was performed in one patient, and three free flaps (5%) could not be salvaged. Cardiovascular disease was significantly associated with flap failure, and venous congestion (thrombosis) was the most common reason for revision surgery. CONCLUSION Cardiovascular disease clearly emerged as a factor related to the failure of free flap surgery, and this issue warrants particular attention in patients for whom free tissue transfer is planned.
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Affiliation(s)
- Beom Jin Lim
- Department of Plastic and Reconstructive Surgery, Jeonbuk National University Medical School, Jeonju, Korea
- Research Institute of Clinical Medicine of Jeonbuk National University-Biomedical Research Institute of Jeonbuk National University Hospital, Jeonju, Korea
| | - Jin Yong Shin
- Department of Plastic and Reconstructive Surgery, Jeonbuk National University Medical School, Jeonju, Korea
- Research Institute of Clinical Medicine of Jeonbuk National University-Biomedical Research Institute of Jeonbuk National University Hospital, Jeonju, Korea
| | - Si-Gyun Roh
- Department of Plastic and Reconstructive Surgery, Jeonbuk National University Medical School, Jeonju, Korea
- Research Institute of Clinical Medicine of Jeonbuk National University-Biomedical Research Institute of Jeonbuk National University Hospital, Jeonju, Korea
| | - Nae-Ho Lee
- Department of Plastic and Reconstructive Surgery, Jeonbuk National University Medical School, Jeonju, Korea
- Research Institute of Clinical Medicine of Jeonbuk National University-Biomedical Research Institute of Jeonbuk National University Hospital, Jeonju, Korea
| | - Yoon Kyu Chung
- Department of Plastic and Reconstructive Surgery, Jeonbuk National University Medical School, Jeonju, Korea
- Research Institute of Clinical Medicine of Jeonbuk National University-Biomedical Research Institute of Jeonbuk National University Hospital, Jeonju, Korea
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Woo HG, Kim HG, Lee KM, Ha SH, Jo H, Heo SH, Chang DI, Kim BJ. Blood viscosity associated with stroke mechanism and early neurological deterioration in middle cerebral artery atherosclerosis. Sci Rep 2023; 13:9384. [PMID: 37296267 PMCID: PMC10256783 DOI: 10.1038/s41598-023-36633-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Accepted: 06/07/2023] [Indexed: 06/12/2023] Open
Abstract
Blood viscosity may affect the mechanisms of stroke and early neurological deterioration (END). We aimed to investigate the relationship between blood viscosity, stroke mechanisms, and END in patients with middle cerebral artery (MCA) infarction. Patients with symptomatic MCA atherosclerosis (≥ 50% stenosis) were recruited. Blood viscosity was compared across patients with different mechanisms of symptomatic MCA disease: in situ thrombo-occlusion (sMCA-IST), artery-to-artery embolism (sMCA-AAE), and local branch occlusion (sMCA-LBO). END was defined as four points increase in the National Institutes of Health Stroke Scale score from baseline during the first week. The association between blood viscosity and END was also evaluated. A total of 360 patients (76 with sMCA-IST, 216 with sMCA-AAE, and 68 with sMCA-LBO) were investigated. Blood viscosity was highest in patients with sMCA-IST, followed by sMCA-AAE and sMCA-LBO (P < 0.001). Blood viscosity was associated with END in patients with MCA disease. Low shear viscosity was associated with END in patients with sMCA- LBO (adjusted odds ratio, aOR 1.524; 95% confidence interval, CI 1.035-2.246), sMCA- IST (aOR 1.365; 95% CI 1.013-1.839), and sMCA- AAE (aOR 1.285; 95% CI 1.010-1.634). Blood viscosity was related to END in patients with stroke caused by MCA disease.
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Affiliation(s)
- Ho Geol Woo
- Department of Neurology, Kyung Hee University College of Medicine, Kyung Hee University Hospital, Seoul, Korea
| | - Hyug-Gi Kim
- Department of Radiology, Kyung Hee University College of Medicine, Kyung Hee University Hospital, Seoul, Korea
| | - Kyung Mi Lee
- Department of Radiology, Kyung Hee University College of Medicine, Kyung Hee University Hospital, Seoul, Korea
| | - Sang Hee Ha
- Department of Neurology, Gil Medical Center, Gachon University, Incheon, Korea
| | - HangJin Jo
- Department of Mechanical Engineering and Division of Advanced Nuclear Engineering, POSTECH, Pohang, Gyeongbuk, Korea
| | - Sung Hyuk Heo
- Department of Neurology, Kyung Hee University College of Medicine, Kyung Hee University Hospital, Seoul, Korea
| | - Dae-Il Chang
- Department of Neurology, Kyung Hee University College of Medicine, Kyung Hee University Hospital, Seoul, Korea
| | - Bum Joon Kim
- Department of Neurology, Asan Medical Center, University of Ulsan, College of Medicine, Song-Pa, PO Box 145, Seoul, 138-600, Korea.
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5
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Lee H, Heo J, Lee IH, Kim YD, Nam HS. Association between blood viscosity and early neurological deterioration in lacunar infarction. Front Neurol 2022; 13:979073. [PMID: 36203995 PMCID: PMC9530465 DOI: 10.3389/fneur.2022.979073] [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: 06/27/2022] [Accepted: 08/22/2022] [Indexed: 11/13/2022] Open
Abstract
Background Understanding the factors related to early neurologic deterioration (END) is crucial in the management of patients with lacunar infarction. Blood viscosity is a significant factor for microvascular perfusion. We investigated the association between blood viscosity and occurrence of END in lacunar infarction. Methods We included consecutive patients admitted for lacunar infarction within 72 h from symptoms onset. END was defined as an increase in the National Institute of Health Stroke Scale (NIHSS) score ≥2 within 24 h of admission. Viscosity was measured within 24 h of hospitalization with a scanning capillary tube viscometer. Viscosity measured at a shear rate of 300 s−1 was defined as systolic blood viscosity (SBV), whereas that measured at a shear rate of 5 s−1 as diastolic blood viscosity (DBV). Results Of the 178 patients included (median age, 65.5; interquartile range [IQR], 56.0, 76.0], END occurred in 33 (18.5%). DBV was significantly higher in patients with END than those without END (13.3 mPa·s [IQR 11.8, 16.0] vs. 12.3 mPa·s [IQR11.0, 13.5]; P = 0.023). In the multivariate analysis, DBV was independently associated with the occurrence of END (odds ratio 1.17; 95% confidence interval 1.01–1.36; P = 0.043). Subgroup analysis showed no heterogeneity in the effect of viscosity on the occurrence of END. Conclusions Blood viscosity at a low shear rate (DBV) was associated with the occurrence of END in patients with lacunar infarction. Blood rheology may be important in pathophysiology of END in patients with lacunar infarction.
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Affiliation(s)
- Hyungwoo Lee
- Department of Neurology, Yonsei University College of Medicine, Seoul, South Korea
| | - JoonNyung Heo
- Department of Neurology, Yonsei University College of Medicine, Seoul, South Korea
| | - Il Hyung Lee
- Department of Neurology, Yonsei University College of Medicine, Seoul, South Korea
| | - Young Dae Kim
- Department of Neurology, Yonsei University College of Medicine, Seoul, South Korea
- Integrative Research Center for Cerebrovascular and Cardiovascular Diseases, Yonsei University College of Medicine, Seoul, South Korea
| | - Hyo Suk Nam
- Department of Neurology, Yonsei University College of Medicine, Seoul, South Korea
- Integrative Research Center for Cerebrovascular and Cardiovascular Diseases, Yonsei University College of Medicine, Seoul, South Korea
- *Correspondence: Hyo Suk Nam
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Al-kuraishy HM, Al-Gareeb AI, Al-Hamash SM, Cavalu S, El-Bouseary MM, Sonbol FI, Batiha GES. Changes in the Blood Viscosity in Patients With SARS-CoV-2 Infection. Front Med (Lausanne) 2022; 9:876017. [PMID: 35783600 PMCID: PMC9247235 DOI: 10.3389/fmed.2022.876017] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 05/31/2022] [Indexed: 12/18/2022] Open
Abstract
Coronavirus disease 2019 (COVID-19) is caused by a novel virus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2-induced hyperinflammation together with alteration of plasma proteins, erythrocyte deformability, and platelet activation, may affect blood viscosity. Thus, this review aimed to study the link between SARS-CoV-2 infection and alteration of blood viscosity in COVID-19 patients. In order to review findings related to hyperviscosity in COVID-19, we suggested a protocol for narrative review of related published COVID-19 articles. Hyperviscosity syndrome is developed in different hematological disorders including multiple myeloma, sickle cell anemia, Waldenstorm macroglobulinemia, polycythemia, and leukemia. In COVID-19, SARS-CoV-2 may affect erythrocyte morphology via binding of membrane cluster of differentiation 147 (CD147) receptors, and B and 3 proteins on the erythrocyte membrane. Variations in erythrocyte fragility and deformability with endothelial dysfunction and oxidative stress in SARS-CoV-2 infection may cause hyperviscosity syndrome in COVID-19. Of interest, hyperviscosity syndrome in COVID-19 may cause poor tissue perfusion, peripheral vascular resistance, and thrombosis. Most of the COVID-19 patients with a blood viscosity more than 3.5 cp may develop coagulation disorders. Of interest, hyperviscosity syndrome is more commonly developed in vaccine recipients who had formerly received the COVID-19 vaccine due to higher underlying immunoglobulin concentrations, and only infrequently in those who have not received the COVID-19 vaccine. Taken together, these observations are untimely too early to give a final connotation between COVID-19 vaccination and the risk for development of hyperviscosity syndrome, consequently prospective and retrospective studies are necessary in this regard.
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Affiliation(s)
- Hayder M. Al-kuraishy
- Department of Clinical Pharmacology and Medicine, College of Medicine, Al-Mustansiriya University, Baghdad, Iraq
| | - Ali I. Al-Gareeb
- Department of Clinical Pharmacology and Medicine, College of Medicine, Al-Mustansiriya University, Baghdad, Iraq
| | | | - Simona Cavalu
- Faculty of Medicine and Pharmacy, University of Oradea, Oradea, Romania
| | - Maisra M. El-Bouseary
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Tanta University, Tanta, Egypt
- *Correspondence: Maisra M. El-Bouseary,
| | - Fatma I. Sonbol
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Tanta University, Tanta, Egypt
| | - Gaber El-Saber Batiha
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, Damanhour, Egypt
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7
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Al-Kuraishy HM, Al-Gareeb AI, El-Bouseary MM, Sonbol FI, Batiha GES. Hyperviscosity syndrome in COVID-19 and related vaccines: exploring of uncertainties. Clin Exp Med 2022:10.1007/s10238-022-00836-x. [PMID: 35608715 PMCID: PMC9128329 DOI: 10.1007/s10238-022-00836-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 04/26/2022] [Indexed: 12/31/2022]
Abstract
Hyperviscosity syndrome (HVS) recently emerged as a complication of coronavirus disease 2019 (COVID-19) and COVID-19 vaccines. Therefore, the objectives of this critical review are to establish the association between COVID-19 and COVID-19 vaccines with the development of HVS. HVS may develop in various viral infections due to impairment of humoral and cellular immunity with elevation of immunoglobulins. COVID-19 can increase blood viscosity (BV) through modulation of fibrinogen, albumin, lipoproteins, and red blood cell (RBC) indices. HVS can cause cardiovascular and neurological complications in COVID-19 like myocardial infarction (MI) and stroke. HVS with or without abnormal RBCs function in COVID-19 participates in the reduction of tissue oxygenation with the development of cardio-metabolic complications and long COVID-19. Besides, HVS may develop in vaccine recipients with previous COVID-19 due to higher underlying Ig concentrations and rarely without previous COVID-19. Similarly, patients with metabolic syndrome are at the highest risk for propagation of HVS after COVID-19 vaccination. In conclusion, COVID-19 and related vaccines are linked with the development of HVS, mainly in patients with previous COVID-19 and underlying metabolic derangements. The possible mechanism of HVS in COVID-19 and related vaccines is increasing levels of fibrinogen and immunoglobulins. However, dehydration, oxidative stress, and inflammatory reactions are regarded as additional contributing factors in the pathogenesis of HVS in COVID-19. However, this critical review cannot determine the final causal relationship between COVID-19 and related vaccines and the development of HVS. Prospective and retrospective studies are warranted in this field.
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Affiliation(s)
- Hayder M Al-Kuraishy
- Department of Clinical Pharmacology and Medicine, College of Medicine, Al-Mustansiriya University, Baghdad, Iraq
| | - Ali I Al-Gareeb
- Department of Clinical Pharmacology and Medicine, College of Medicine, Al-Mustansiriya University, Baghdad, Iraq
| | - Maisra M El-Bouseary
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Tanta University, Tanta, Egypt.
| | - Fatma I Sonbol
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Tanta University, Tanta, Egypt
| | - Gaber El-Saber Batiha
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, Damanhour, 22511, AlBeheira, Egypt.
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8
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Ahmadpoor P, Aglae C, Cariou S, Pambrun E, Renaud S, Garo F, Darmon R, Schultz C, Prelipcean C, Reboul P, Moranne O. Physiological role of plasma and its components and the clinical implications of different methods of apheresis: A narrative review. Ther Apher Dial 2020; 25:262-272. [PMID: 32710797 DOI: 10.1111/1744-9987.13567] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 06/17/2020] [Accepted: 07/22/2020] [Indexed: 12/23/2022]
Abstract
Nowadays, therapeutic plasmapheresis (TP) is accepted as part of the treatment for specific groups of diseases. The availability of different methods, including double filtration and adsorption, increases selectivity for the removal of substances. However, the use of these techniques requires a thorough understanding of the characteristics and components of plasma. By considering pivotal papers from several databases, the aim of this narrative review is to describe the characteristics of plasma related to apheresis techniques. We have tried to cover the clinical implications including physiology, estimation of plasma volume, viscosity, and a description of its components including the size, volume of distribution, and half-lives of the different substances to be removed or maintained depending on the clinical situation and applied apheresis technique. Applying this knowledge will help us to choose the right method and dosage and improve the efficacy of the procedure by preventing or addressing any complications.
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Affiliation(s)
- Pedram Ahmadpoor
- Service Nephrologie-Dialyse-Aphérèse, CHU Carémeau, Université de Montpellier-Nîmes, Nîmes, France
| | - Cedric Aglae
- Service Nephrologie-Dialyse-Aphérèse, CHU Carémeau, Université de Montpellier-Nîmes, Nîmes, France
| | - Sylvain Cariou
- Service Nephrologie-Dialyse-Aphérèse, CHU Carémeau, Université de Montpellier-Nîmes, Nîmes, France
| | - Emilie Pambrun
- Service Nephrologie-Dialyse-Aphérèse, CHU Carémeau, Université de Montpellier-Nîmes, Nîmes, France
| | - Sophie Renaud
- Service Nephrologie-Dialyse-Aphérèse, CHU Carémeau, Université de Montpellier-Nîmes, Nîmes, France
| | - Florian Garo
- Service Nephrologie-Dialyse-Aphérèse, CHU Carémeau, Université de Montpellier-Nîmes, Nîmes, France
| | - Ruben Darmon
- Service Nephrologie-Dialyse-Aphérèse, CHU Carémeau, Université de Montpellier-Nîmes, Nîmes, France
| | - Celine Schultz
- Service Nephrologie-Dialyse-Aphérèse, CHU Carémeau, Université de Montpellier-Nîmes, Nîmes, France
| | - Camelia Prelipcean
- Service Nephrologie-Dialyse-Aphérèse, CHU Carémeau, Université de Montpellier-Nîmes, Nîmes, France
| | - Pascal Reboul
- Service Nephrologie-Dialyse-Aphérèse, CHU Carémeau, Université de Montpellier-Nîmes, Nîmes, France
| | - Olivier Moranne
- Service Nephrologie-Dialyse-Aphérèse, CHU Carémeau, Université de Montpellier-Nîmes, Nîmes, France.,EA2415, Université de Montpellier, Montpellier, France
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9
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Vlaar AP, Oczkowski S, de Bruin S, Wijnberge M, Antonelli M, Aubron C, Aries P, Duranteau J, Juffermans NP, Meier J, Murphy GJ, Abbasciano R, Muller M, Shah A, Perner A, Rygaard S, Walsh TS, Guyatt G, Dionne JC, Cecconi M. Transfusion strategies in non-bleeding critically ill adults: a clinical practice guideline from the European Society of Intensive Care Medicine. Intensive Care Med 2020; 46:673-696. [PMID: 31912207 PMCID: PMC7223433 DOI: 10.1007/s00134-019-05884-8] [Citation(s) in RCA: 104] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 11/26/2019] [Indexed: 01/28/2023]
Abstract
OBJECTIVE To develop evidence-based clinical practice recommendations regarding transfusion practices in non-bleeding, critically ill adults. DESIGN A task force involving 13 international experts and three methodologists used the GRADE approach for guideline development. METHODS The task force identified four main topics: red blood cell transfusion thresholds, red blood cell transfusion avoidance strategies, platelet transfusion, and plasma transfusion. The panel developed structured guideline questions using population, intervention, comparison, and outcomes (PICO) format. RESULTS The task force generated 16 clinical practice recommendations (3 strong recommendations, 13 conditional recommendations), and identified five PICOs with insufficient evidence to make any recommendation. CONCLUSIONS This clinical practice guideline provides evidence-based recommendations and identifies areas where further research is needed regarding transfusion practices and transfusion avoidance in non-bleeding, critically ill adults.
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Affiliation(s)
- Alexander P Vlaar
- Department of Intensive Care Medicine, Amsterdam UMC, Location AMC, Amsterdam, The Netherlands.
- Department of Intensive Care Medicine, University of Amsterdam, Room, C3-430, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
| | - Simon Oczkowski
- Department of Medicine, McMaster University, Hamilton, Canada
- Guidelines in Intensive Care, Development and Evaluation (GUIDE) Group, Hamilton, Canada
- Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Canada
| | - Sanne de Bruin
- Department of Intensive Care Medicine, Amsterdam UMC, Location AMC, Amsterdam, The Netherlands
| | - Marije Wijnberge
- Department of Intensive Care Medicine, Amsterdam UMC, Location AMC, Amsterdam, The Netherlands
- Department of Anaesthesiology, Amsterdam UMC, Location AMC, Amsterdam, The Netherlands
| | - Massimo Antonelli
- Department of Anaesthesiology and Intensive Care Medicine, Fondazione Policlinico Universitario A.Gemelli IRCCS, Rome, Italy
- Istituto di Anaesthesiology e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Cecile Aubron
- Department of Intensive Care Medicine, Centre Hospitalier Régional et Universitaire de Brest, Université de Bretagne Occidentale, Site La Cavale Blanche, Brest, France
| | - Philippe Aries
- Department of Intensive Care Medicine, Centre Hospitalier Régional et Universitaire de Brest, Université de Bretagne Occidentale, Site La Cavale Blanche, Brest, France
| | - Jacques Duranteau
- Department of Anaesthesia and Intensive Care, Hôpitaux Universitaires Paris Sud (HUPS), Orsay, France
| | - Nicole P Juffermans
- Department of Intensive Care Medicine, Amsterdam UMC, Location AMC, Amsterdam, The Netherlands
| | - Jens Meier
- Department of Anesthesiology and Critical Care Medicine, Faculty of Medicine, Kepler University, Linz, Austria
| | - Gavin J Murphy
- Cardiovascular, Department of Cardiovascular Sciences, NIHR Leicester Biomedical Research Centre, College of Life Sciences, University of Leicester, Leicester, LE3 9QP, UK
| | - Riccardo Abbasciano
- Cardiovascular, Department of Cardiovascular Sciences, NIHR Leicester Biomedical Research Centre, College of Life Sciences, University of Leicester, Leicester, LE3 9QP, UK
| | - Marcella Muller
- Department of Intensive Care Medicine, Amsterdam UMC, Location AMC, Amsterdam, The Netherlands
| | - Akshay Shah
- Radcliffe Department of Medicine, University of Oxford, Oxford, UK
- Adult Intensive Care Unit, John Radcliffe Hospital, Oxford, UK
| | - Anders Perner
- Department of Intensive Care, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Sofie Rygaard
- Department of Intensive Care, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Timothy S Walsh
- Anaesthetics, Critical Care, and Pain Medicine, University of Edinburgh, Edinburgh, Scotland
| | - Gordon Guyatt
- Department of Medicine, McMaster University, Hamilton, Canada
- Guidelines in Intensive Care, Development and Evaluation (GUIDE) Group, Hamilton, Canada
- Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Canada
| | - J C Dionne
- Department of Medicine, McMaster University, Hamilton, Canada
- Guidelines in Intensive Care, Development and Evaluation (GUIDE) Group, Hamilton, Canada
- Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Canada
| | - Maurizio Cecconi
- Department of Anaesthesia and Intensive Care Medicine, Humanitas Clinical and Research Centre-IRCCS, Rozzano, Milan, Italy
- Humanitas University, Via Rita Levi Montalcini, Pieve Emanuele, Milan, Italy
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Naumann DN, Hazeldine J, Bishop J, Midwinter MJ, Harrison P, Nash G, Hutchings SD. Impact of plasma viscosity on microcirculatory flow after traumatic haemorrhagic shock: A prospective observational study. Clin Hemorheol Microcirc 2019; 71:71-82. [PMID: 29843227 DOI: 10.3233/ch-180397] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Preclinical studies report that higher plasma viscosity improves microcirculatory flow after haemorrhagic shock and resuscitation, but no clinical study has tested this hypothesis. OBJECTIVE We investigated the relationship between plasma viscosity and sublingual microcirculatory flow in patients during resuscitation for traumatic haemorrhagic shock (THS). METHODS Sublingual video-microscopy was performed for 20 trauma patients with THS as soon as feasible in hospital, and then at 24 h and 48 h. Values were obtained for total vessel density, perfused vessel density, proportion of perfused vessels, microcirculatory flow index (MFI), microcirculatory heterogeneity index (MHI), and Point of Care Microcirculation (POEM) scores. Plasma viscosity was measured using a Wells-Brookfield cone and plate micro-viscometer. Logistic regression analyses examined relationships between microcirculatory parameters and plasma viscosity, adjusting for covariates (systolic blood pressure, heart rate, haematocrit, rate and volume of fluids, and rate of noradrenaline). RESULTS Higher plasma viscosity was not associated with improved microcirculatory parameters. Instead, there were weakly significant associations between higher plasma viscosity and lower (poorer) MFI (p = 0.040), higher (worse) MHI (p = 0.033), and lower (worse) POEM scores (p = 0.039). CONCLUSIONS The current study did not confirm the hypothesis that higher plasma viscosity improves microcirculatory flow dynamics in patients with THS. Further clinical investigations are warranted to determine whether viscosity is a physical parameter of importance during resuscitation of these patients.
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Affiliation(s)
- David N Naumann
- Academic Department of Military Surgery and Trauma, Royal Centre for Defence Medicine, Queen Elizabeth Hospital, Birmingham, UK.,Institute of Inflammation and Ageing, University of Birmingham Research Laboratories, Queen Elizabeth Hospital, Birmingham, UK.,National Institute for Health Research Surgical Reconstruction and Microbiology Research Centre, Queen Elizabeth Hospital, Birmingham, UK
| | - Jon Hazeldine
- Institute of Inflammation and Ageing, University of Birmingham Research Laboratories, Queen Elizabeth Hospital, Birmingham, UK.,National Institute for Health Research Surgical Reconstruction and Microbiology Research Centre, Queen Elizabeth Hospital, Birmingham, UK
| | - Jon Bishop
- National Institute for Health Research Surgical Reconstruction and Microbiology Research Centre, Queen Elizabeth Hospital, Birmingham, UK
| | - Mark J Midwinter
- School of Biomedical Sciences, Faculty of Medicine, University of Queensland, Brisbane, Australia
| | - Paul Harrison
- Institute of Inflammation and Ageing, University of Birmingham Research Laboratories, Queen Elizabeth Hospital, Birmingham, UK
| | - Gerard Nash
- Institute of Cardiovascular Science, University of Birmingham, UK
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Mushtaq M, Abdul Mateen M, Kim UH. Hyperglycemia associated blood viscosity can be a nexus stimuli. Clin Hemorheol Microcirc 2019; 71:103-112. [DOI: 10.3233/ch-180426] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Mazhar Mushtaq
- Department of Basic Sciences, Sulaiman AlRajhi Colleges, Medical College, Al-Qaseem, KSA
| | - Muhammad Abdul Mateen
- Department of Basic Sciences, Sulaiman AlRajhi Colleges, Medical College, Al-Qaseem, KSA
| | - Uh-Hyun Kim
- Institute of Cardiovascular Research, Chonbuk National University Medical School, Jeonju, South Korea
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Chung W, Côté E, Roland R. Tetralogy of Fallot with concurrent patent foramen ovale and tricuspid valve dysplasia in a dog. THE CANADIAN VETERINARY JOURNAL = LA REVUE VETERINAIRE CANADIENNE 2018; 59:993-996. [PMID: 30197443 PMCID: PMC6091122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The echocardiographic findings of a young Pomeranian-cross dog with tetralogy of Fallot, patent foramen ovale, and tricuspid valve dysplasia are described. Ongoing medical management of hypoxemia and erythrocytosis was carried out and the dog survived to 2 years of age. Treatment options for tetralogy of Fallot are discussed.
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Affiliation(s)
- Wilson Chung
- Atlantic Veterinary College, 550 University Avenue, Charlottetown, Prince Edward Island C1A 4P3 (Chung, Côté); Metropolitan Veterinary Associates - Cardiology, 2626 Van Buren Avenue, Norristown, Pennsylvania 19403, USA (Roland)
| | - Etienne Côté
- Atlantic Veterinary College, 550 University Avenue, Charlottetown, Prince Edward Island C1A 4P3 (Chung, Côté); Metropolitan Veterinary Associates - Cardiology, 2626 Van Buren Avenue, Norristown, Pennsylvania 19403, USA (Roland)
| | - Risa Roland
- Atlantic Veterinary College, 550 University Avenue, Charlottetown, Prince Edward Island C1A 4P3 (Chung, Côté); Metropolitan Veterinary Associates - Cardiology, 2626 Van Buren Avenue, Norristown, Pennsylvania 19403, USA (Roland)
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13
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Caneo LF, Matte GS, Guimarães DP, Viotto G, Mazzeto M, Cestari I, Neirotti RA, Jatene MB, Wang S, Ündar A, Chang Junior J, Jatene FB. Functional Performance of Different Venous Limb Options in Simulated Neonatal/Pediatric Cardiopulmonary Bypass Circuits. Braz J Cardiovasc Surg 2018; 33:224-232. [PMID: 30043914 PMCID: PMC6089135 DOI: 10.21470/1678-9741-2018-0074] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 03/09/2018] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE Hemodilution is a concern in cardiopulmonary bypass (CPB). Using a smaller dual tubing rather than a single larger inner diameter (ID) tubing in the venous limb to decrease prime volume has been a standard practice. The purpose of this study is to evaluate these tubing options. METHODS Four different CPB circuits primed with blood (hematocrit 30%) were investigated. Two setups were used with two circuits for each one. In Setup I, a neonatal oxygenator was connected to dual 3/16" ID venous limbs (Circuit A) or to a single 1/4" ID venous limb (Circuit B); and in Setup II, a pediatric oxygenator was connected to dual 1/4" ID venous limbs (Circuit C) or a single 3/8" ID venous limb (Circuit D). Trials were conducted at arterial flow rates of 500 ml/min up to 1500 ml/min (Setup I) and up to 3000 ml/min (Setup II), at 36°C and 28°C. RESULTS Circuit B exhibited a higher venous flow rate than Circuit A, and Circuit D exhibited a higher venous flow rate than Circuit C, at both temperatures. Flow resistance was significantly higher in Circuits A and C than in Circuits B (P<0.001) and D (P<0.001), respectively. CONCLUSION A single 1/4" venous limb is better than dual 3/16" venous limbs at all flow rates, up to 1500 ml/min. Moreover, a single 3/8" venous limb is better than dual 1/4" venous limbs, up to 3000 ml/min. Our findings strongly suggest a revision of perfusion practice to include single venous limb circuits for CPB.
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Affiliation(s)
- Luiz Fernando Caneo
- Cardiovascular Surgery Division, Instituto do Coração, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (InCor-HCFMUSP), São Paulo, SP, Brazil
| | - Gregory S Matte
- Department of Cardiac Surgery, Boston Children's Hospital, Boston, MA, USA
| | - Daniel Peres Guimarães
- Cardiovascular Surgery Division, Instituto do Coração, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (InCor-HCFMUSP), São Paulo, SP, Brazil
| | - Guilherme Viotto
- Cardiovascular Surgery Division, Instituto do Coração, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (InCor-HCFMUSP), São Paulo, SP, Brazil
| | - Marcelo Mazzeto
- Cardiovascular Surgery Division, Instituto do Coração, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (InCor-HCFMUSP), São Paulo, SP, Brazil
| | - Idagene Cestari
- Cardiovascular Surgery Division, Instituto do Coração, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (InCor-HCFMUSP), São Paulo, SP, Brazil
| | - Rodolfo A Neirotti
- Clinical Professor of Surgery and Pediatrics, Emeritus Michigan State University, MI, USA
| | - Marcelo B Jatene
- Cardiovascular Surgery Division, Instituto do Coração, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (InCor-HCFMUSP), São Paulo, SP, Brazil
| | - Shigang Wang
- Pediatric Cardiovascular Research Center, Department of Pediatrics; Public Health Sciences; Surgery and Bioengineering, Penn State Health Milton S. Hershey Medical Center, Penn State College of Medicine, Penn State Health Children's Hospital, Hershey, PA, USA
| | - Akif Ündar
- Pediatric Cardiovascular Research Center, Department of Pediatrics; Public Health Sciences; Surgery and Bioengineering, Penn State Health Milton S. Hershey Medical Center, Penn State College of Medicine, Penn State Health Children's Hospital, Hershey, PA, USA
| | - João Chang Junior
- Department of Industrial Engineering, FEI University Center, São Paulo, Brazil
| | - Fabio B Jatene
- Cardiovascular Surgery Division, Instituto do Coração, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (InCor-HCFMUSP), São Paulo, SP, Brazil
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14
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Woo TH. Feasibility study for radiation therapy using nano-robotics incorporated with three-dimensional (3D) printing. RENDICONTI LINCEI 2016. [DOI: 10.1007/s12210-016-0559-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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15
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Ribeiro S, Garrido P, Fernandes J, Vala H, Rocha-Pereira P, Costa E, Belo L, Reis F, Santos-Silva A. Impaired renal endothelial nitric oxide synthase and reticulocyte production as modulators of hypertension induced by rHuEPO in the rat. Life Sci 2016; 151:147-156. [PMID: 26924494 DOI: 10.1016/j.lfs.2016.02.088] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 02/12/2016] [Accepted: 02/24/2016] [Indexed: 01/15/2023]
Abstract
Our aim was to study the effect of a broad range of recombinant human erythropoietin (rHuEPO) doses on hematological and biochemical parameters, blood pressure (BP), renal function and damage in the rat, focusing on endothelial nitric oxide synthase (eNOS) and hypoxia-inducible factors (HIFs). Male Wistar rats were divided in 5 groups receiving different doses of rHuEPO (100, 200, 400 and 600IU/kg body weight (BW)/week) and saline solution (control), during 3weeks. Blood and 24h urine were collected to perform hematological and biochemical analysis. BP was measured by the tail-cuff method. Kidney tissue was collected to mRNA and protein expression assays and to characterize renal lesions. A dose-dependent increase in red blood cells count, hematocrit and hemoglobin levels was found with rHuEPO therapy, in rHuEPO200, rHuEPO400 and rHuEPO600 groups. Increased reticulocyte count was found in rHuEPO400 and rHuEPO600 groups. BP raised in all groups receiving rHuEPO. The rHuEPO200 and rHuEPO600 groups presented increased kidney protein levels of HIF2α, a reduction in kidney protein levels of eNOS, and the highest grade of vascular and tubular renal lesions. Our study showed that rHuEPO-induced hypertension is present before significant hematological changes occur and, therefore, might involve direct (renal) and indirect (hematological) effects, which varies according to the dose used. The presence of renal hypoxia reduces eNOS activity. Excessive erythrocytosis increases blood hyperviscosity, which can be modulated by an increase in reticulocytes. Hypertension leads to early renal damage without alterations in traditional markers of renal function, thus underestimating the serious adverse effects and risks.
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Affiliation(s)
- Sandra Ribeiro
- Research Unit on Applied Molecular Biosciences (UCIBIO), REQUIMTE, Department of Biological Sciences, Laboratory of Biochemistry, Faculty of Pharmacy, University of Porto, Porto, Portugal
| | - Patrícia Garrido
- Laboratory of Pharmacology & Experimental Therapeutics, Institute for Biomedical Imaging and Life Sciences (IBILI), Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - João Fernandes
- Laboratory of Pharmacology & Experimental Therapeutics, Institute for Biomedical Imaging and Life Sciences (IBILI), Faculty of Medicine, University of Coimbra, Coimbra, Portugal; Center for Neuroscience and Cell Biology-Institute for Biomedical Imaging and Life Sciences (CNC.IBILI) Research Unit, University of Coimbra, Coimbra, Portugal
| | - Helena Vala
- Center for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB) and Center for Studies in Education and Health Technologies (CI&DETS), Agrarian School of Viseu, Polytechnic Institute of Viseu, Viseu, Portugal
| | - Petronila Rocha-Pereira
- Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Covilhã, Portugal
| | - Elísio Costa
- Research Unit on Applied Molecular Biosciences (UCIBIO), REQUIMTE, Department of Biological Sciences, Laboratory of Biochemistry, Faculty of Pharmacy, University of Porto, Porto, Portugal
| | - Luís Belo
- Research Unit on Applied Molecular Biosciences (UCIBIO), REQUIMTE, Department of Biological Sciences, Laboratory of Biochemistry, Faculty of Pharmacy, University of Porto, Porto, Portugal
| | - Flávio Reis
- Laboratory of Pharmacology & Experimental Therapeutics, Institute for Biomedical Imaging and Life Sciences (IBILI), Faculty of Medicine, University of Coimbra, Coimbra, Portugal; Center for Neuroscience and Cell Biology-Institute for Biomedical Imaging and Life Sciences (CNC.IBILI) Research Unit, University of Coimbra, Coimbra, Portugal
| | - Alice Santos-Silva
- Research Unit on Applied Molecular Biosciences (UCIBIO), REQUIMTE, Department of Biological Sciences, Laboratory of Biochemistry, Faculty of Pharmacy, University of Porto, Porto, Portugal.
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16
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Schlager O, Gschwandtner ME, Willfort-Ehringer A, Kurz M, Mueller M, Koppensteiner R, Heinz G. Transcutaneous oxygen tension monitoring in critically ill patients receiving packed red blood cells. J Crit Care 2014; 29:1057-62. [PMID: 25012959 DOI: 10.1016/j.jcrc.2014.05.028] [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: 01/22/2014] [Revised: 05/12/2014] [Accepted: 05/29/2014] [Indexed: 10/25/2022]
Abstract
PURPOSE Whether transfusions of packed red blood cells (PRBCs) affect tissue oxygenation in stable critically ill patients is still matter of discussion. The microvascular capacity for tissue oxygenation can be determined noninvasively by measuring transcutaneous oxygen tension (tcpO2). The aim of this study was to assess tissue oxygenation by measuring tcpO2 in stable critically ill patients receiving PRBC transfusions. METHODS Nineteen stable critically ill patients, who received 2 units of PRBC, were prospectively included into this pilot study. Transcutaneous oxygen tension was measured continuously during PRBC transfusions using Clark's electrodes. In addition, whole blood viscosity and global hemodynamics were determined. RESULTS Reliable measurement signals during continuous tcpO2 monitoring were observed in 17 of 19 included patients. Transcutaneous oxygen tension was related to the global oxygen consumption (r=-0.78; P=.003), the arterio-venous oxygen content difference (r=-0.65; P=.005), and the extraction rate (r=-0.71; P=.02). The transfusion-induced increase of the hemoglobin concentration was paralleled by an increase of the whole blood viscosity (P<.001). Microvascular tissue oxygenation by means of tcpO2 was not affected by PRBC transfusions (P=.46). Packed red blood cell transfusions resulted in an increase of global oxygen delivery (P=.02) and central venous oxygen saturation (P=.01), whereas oxygen consumption remained unchanged (P=.72). CONCLUSIONS In stable critically ill patients, microvascular tissue oxygenation can be continuously monitored by Clark's tcpO2 electrodes. According to continuous tcpO2 measurements, the microvascular tissue oxygenation is not affected by PRBC transfusions.
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Affiliation(s)
- Oliver Schlager
- Department of Medicine II, Division of Angiology, Medical University of Vienna, Vienna, Austria
| | - Michael E Gschwandtner
- Department of Medicine II, Division of Angiology, Medical University of Vienna, Vienna, Austria.
| | | | - Martin Kurz
- Department for Blood Group Serology and Transfusion Medicine, Medical University of Vienna, Vienna, Austria
| | - Markus Mueller
- Department of Medicine II, Division of Angiology, Medical University of Vienna, Vienna, Austria
| | - Renate Koppensteiner
- Department of Medicine II, Division of Angiology, Medical University of Vienna, Vienna, Austria
| | - Gottfried Heinz
- Department of Medicine II, Division of Cardiology, Intensive Care Unit, Medical University of Vienna, Vienna, Austria
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Schwen LO, Krauss M, Niederalt C, Gremse F, Kiessling F, Schenk A, Preusser T, Kuepfer L. Spatio-temporal simulation of first pass drug perfusion in the liver. PLoS Comput Biol 2014; 10:e1003499. [PMID: 24625393 PMCID: PMC3952820 DOI: 10.1371/journal.pcbi.1003499] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 01/21/2014] [Indexed: 01/21/2023] Open
Abstract
The liver is the central organ for detoxification of xenobiotics in the body. In pharmacokinetic modeling, hepatic metabolization capacity is typically quantified as hepatic clearance computed as degradation in well-stirred compartments. This is an accurate mechanistic description once a quasi-equilibrium between blood and surrounding tissue is established. However, this model structure cannot be used to simulate spatio-temporal distribution during the first instants after drug injection. In this paper, we introduce a new spatially resolved model to simulate first pass perfusion of compounds within the naive liver. The model is based on vascular structures obtained from computed tomography as well as physiologically based mass transfer descriptions obtained from pharmacokinetic modeling. The physiological architecture of hepatic tissue in our model is governed by both vascular geometry and the composition of the connecting hepatic tissue. In particular, we here consider locally distributed mass flow in liver tissue instead of considering well-stirred compartments. Experimentally, the model structure corresponds to an isolated perfused liver and provides an ideal platform to address first pass effects and questions of hepatic heterogeneity. The model was evaluated for three exemplary compounds covering key aspects of perfusion, distribution and metabolization within the liver. As pathophysiological states we considered the influence of steatosis and carbon tetrachloride-induced liver necrosis on total hepatic distribution and metabolic capacity. Notably, we found that our computational predictions are in qualitative agreement with previously published experimental data. The simulation results provide an unprecedented level of detail in compound concentration profiles during first pass perfusion, both spatio-temporally in liver tissue itself and temporally in the outflowing blood. We expect our model to be the foundation of further spatially resolved models of the liver in the future.
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Affiliation(s)
| | - Markus Krauss
- Computational Systems Biology, Bayer Technology Services, Leverkusen, Germany
- Aachen Institute for Advanced Study in Computational Engineering Sciences, RWTH Aachen University, Aachen, Germany
| | - Christoph Niederalt
- Computational Systems Biology, Bayer Technology Services, Leverkusen, Germany
| | - Felix Gremse
- Experimental Molecular Imaging, RWTH Aachen University, Aachen, Germany
| | - Fabian Kiessling
- Experimental Molecular Imaging, RWTH Aachen University, Aachen, Germany
| | | | - Tobias Preusser
- Fraunhofer MEVIS, Bremen, Germany
- School of Engineering and Science, Jacobs University, Bremen, Germany
| | - Lars Kuepfer
- Computational Systems Biology, Bayer Technology Services, Leverkusen, Germany
- Institute of Applied Microbiology, RWTH Aachen University, Aachen, Germany
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18
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Donati A, Damiani E, Luchetti M, Domizi R, Scorcella C, Carsetti A, Gabbanelli V, Carletti P, Bencivenga R, Vink H, Adrario E, Piagnerelli M, Gabrielli A, Pelaia P, Ince C. Microcirculatory effects of the transfusion of leukodepleted or non-leukodepleted red blood cells in patients with sepsis: a pilot study. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2014; 18:R33. [PMID: 24528648 PMCID: PMC4057400 DOI: 10.1186/cc13730] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Accepted: 01/28/2014] [Indexed: 12/14/2022]
Abstract
Introduction Microvascular alterations impair tissue oxygenation during sepsis. A red blood cell (RBC) transfusion increases oxygen (O2) delivery but rarely improves tissue O2 uptake in patients with sepsis. Possible causes include RBC alterations due to prolonged storage or residual leukocyte-derived inflammatory mediators. The aim of this study was to compare the effects of two types of transfused RBCs on microcirculation in patients with sepsis. Methods In a prospective randomized trial, 20 patients with sepsis were divided into two separate groups and received either non-leukodepleted (n = 10) or leukodepleted (n = 10) RBC transfusions. Microvascular density and perfusion were assessed with sidestream dark field (SDF) imaging sublingually, before and 1 hour after transfusions. Thenar tissue O2 saturation (StO2) and tissue hemoglobin index (THI) were determined with near-infrared spectroscopy, and a vascular occlusion test was performed. The microcirculatory perfused boundary region was assessed in SDF images as an index of glycocalyx damage, and glycocalyx compounds (syndecan-1, hyaluronan, and heparan sulfate) were measured in the serum. Results No differences were observed in microvascular parameters at baseline and after transfusion between the groups, except for the proportion of perfused vessels (PPV) and blood flow velocity, which were higher after transfusion in the leukodepleted group. Microvascular flow index in small vessels (MFI) and blood flow velocity exhibited different responses to transfusion between the two groups (P = 0.03 and P = 0.04, respectively), with a positive effect of leukodepleted RBCs. When within-group changes were examined, microcirculatory improvement was observed only in patients who received leukodepleted RBC transfusion as suggested by the increase in De Backer score (P = 0.02), perfused vessel density (P = 0.04), PPV (P = 0.01), and MFI (P = 0.04). Blood flow velocity decreased in the non-leukodepleted group (P = 0.03). THI and StO2 upslope increased in both groups. StO2 and StO2 downslope increased in patients who received non-leukodepleted RBC transfusions. Syndecan-1 increased after the transfusion of non-leukodepleted RBCs (P = 0.03). Conclusions This study does not show a clear superiority of leukodepleted over non-leukodepleted RBC transfusions on microvascular perfusion in patients with sepsis, although it suggests a more favorable effect of leukodepleted RBCs on microcirculatory convective flow. Further studies are needed to confirm these findings. Trial registration ClinicalTrials.gov, NCT01584999
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Tauhardt L, Pretzel D, Kempe K, Gottschaldt M, Pohlers D, Schubert US. Zwitterionic poly(2-oxazoline)s as promising candidates for blood contacting applications. Polym Chem 2014. [DOI: 10.1039/c4py00434e] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The hemocompatibility and cytotoxicity of zwitterionic poly(2-oxazoline)s are investigated.
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Affiliation(s)
- Lutz Tauhardt
- Laboratory of Organic and Macromolecular Chemistry (IOMC)
- Friedrich Schiller University Jena
- 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM)
- Friedrich Schiller University Jena
| | - David Pretzel
- Laboratory of Organic and Macromolecular Chemistry (IOMC)
- Friedrich Schiller University Jena
- 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM)
- Friedrich Schiller University Jena
| | - Kristian Kempe
- Laboratory of Organic and Macromolecular Chemistry (IOMC)
- Friedrich Schiller University Jena
- 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM)
- Friedrich Schiller University Jena
| | - Michael Gottschaldt
- Laboratory of Organic and Macromolecular Chemistry (IOMC)
- Friedrich Schiller University Jena
- 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM)
- Friedrich Schiller University Jena
| | - Dirk Pohlers
- Centre for Diagnostic at the Clinic of Chemnitz
- 09116 Chemnitz, Germany
| | - Ulrich S. Schubert
- Laboratory of Organic and Macromolecular Chemistry (IOMC)
- Friedrich Schiller University Jena
- 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM)
- Friedrich Schiller University Jena
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McGinnis WR, Audhya T, Edelson SM. Proposed toxic and hypoxic impairment of a brainstem locus in autism. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2013; 10:6955-7000. [PMID: 24336025 PMCID: PMC3881151 DOI: 10.3390/ijerph10126955] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Revised: 11/07/2013] [Accepted: 11/11/2013] [Indexed: 01/15/2023]
Abstract
Electrophysiological findings implicate site-specific impairment of the nucleus tractus solitarius (NTS) in autism. This invites hypothetical consideration of a large role for this small brainstem structure as the basis for seemingly disjointed behavioral and somatic features of autism. The NTS is the brain's point of entry for visceral afference, its relay for vagal reflexes, and its integration center for autonomic control of circulatory, immunological, gastrointestinal, and laryngeal function. The NTS facilitates normal cerebrovascular perfusion, and is the seminal point for an ascending noradrenergic system that modulates many complex behaviors. Microvascular configuration predisposes the NTS to focal hypoxia. A subregion--the "pNTS"--permits exposure to all blood-borne neurotoxins, including those that do not readily transit the blood-brain barrier. Impairment of acetylcholinesterase (mercury and cadmium cations, nitrates/nitrites, organophosphates, monosodium glutamate), competition for hemoglobin (carbon monoxide, nitrates/nitrites), and higher blood viscosity (net systemic oxidative stress) are suggested to potentiate microcirculatory insufficiency of the NTS, and thus autism.
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Affiliation(s)
- Woody R. McGinnis
- Autism Research Institute, 4182 Adams Avenue, San Diego, CA 92116, USA; E-Mail:
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +1-541-326-8822; Fax: +1-619-563-6840
| | - Tapan Audhya
- Division of Endocrinology, Department of Medicine, New York University Medical School, New York, NY 10016, USA; E-Mail:
| | - Stephen M. Edelson
- Autism Research Institute, 4182 Adams Avenue, San Diego, CA 92116, USA; E-Mail:
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El-Bediwi AB, Saad M, El-kott AF, Eid E. Influence of electromagnetic radiation produced by mobile phone on some biophysical blood properties in rats. Cell Biochem Biophys 2013; 65:297-300. [PMID: 23054912 DOI: 10.1007/s12013-012-9432-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Effects of electromagnetic radiation produced by mobile phone on blood viscosity, plasma viscosity, hemolysis, Osmotic fragility, and blood components of rats have been investigated. Experimental results show that there are significant change on blood components and its viscosity which affects on a blood circulation due to many body problems. Red blood cells, White blood cells, and Platelets are broken after exposure to electromagnetic radiation produced by mobile phone. Also blood viscosity and plasma viscosity values are increased but Osmotic fragility value decreased after exposure to electromagnetic radiation produced by mobile phone.
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Affiliation(s)
- Abu Bakr El-Bediwi
- Metal Physics laboratory, Department of Physics, Faculty of Science, Mansoura University, Mansoura, Egypt.
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Knop K, Pretzel D, Urbanek A, Rudolph T, Scharf DH, Schallon A, Wagner M, Schubert S, Kiehntopf M, Brakhage AA, Schacher FH, Schubert US. Star-Shaped Drug Carriers for Doxorubicin with POEGMA and POEtOxMA Brush-like Shells: A Structural, Physical, and Biological Comparison. Biomacromolecules 2013; 14:2536-48. [DOI: 10.1021/bm400091n] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Katrin Knop
- Laboratory of Organic
and Macromolecular
Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany
- Jena Center for Soft Matter
(JCSM), Friedrich Schiller University Jena, Philosophenweg 8, 07743 Jena, Germany
| | - David Pretzel
- Laboratory of Organic
and Macromolecular
Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany
- Jena Center for Soft Matter
(JCSM), Friedrich Schiller University Jena, Philosophenweg 8, 07743 Jena, Germany
| | - Annett Urbanek
- Laboratory of Organic
and Macromolecular
Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany
- Jena Center for Soft Matter
(JCSM), Friedrich Schiller University Jena, Philosophenweg 8, 07743 Jena, Germany
| | - Tobias Rudolph
- Laboratory of Organic
and Macromolecular
Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany
- Jena Center for Soft Matter
(JCSM), Friedrich Schiller University Jena, Philosophenweg 8, 07743 Jena, Germany
| | - Daniel H. Scharf
- Leibniz Institute for Natural
Product Research and Infection Biology, Hans Knöll Institute, Beutenbergstrasse 11a, 07745 Jena, Germany
| | - Anja Schallon
- Laboratory of Organic
and Macromolecular
Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany
- Jena Center for Soft Matter
(JCSM), Friedrich Schiller University Jena, Philosophenweg 8, 07743 Jena, Germany
| | - Michael Wagner
- Laboratory of Organic
and Macromolecular
Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany
- Jena Center for Soft Matter
(JCSM), Friedrich Schiller University Jena, Philosophenweg 8, 07743 Jena, Germany
| | - Stephanie Schubert
- Jena Center for Soft Matter
(JCSM), Friedrich Schiller University Jena, Philosophenweg 8, 07743 Jena, Germany
- Department of Pharmaceutical
Technology, Institute of Pharmacy, Friedrich-Schiller-University Jena, Otto-Schott-Strasse 41, 07745 Jena, Germany
| | - Michael Kiehntopf
- Institute for Clinical Chemistry
and Laboratory Diagnostics, Jena University Hospital, Erlanger Allee 101, 07740 Jena, Germany
| | - Axel A. Brakhage
- Jena Center for Soft Matter
(JCSM), Friedrich Schiller University Jena, Philosophenweg 8, 07743 Jena, Germany
- Leibniz Institute for Natural
Product Research and Infection Biology, Hans Knöll Institute, Beutenbergstrasse 11a, 07745 Jena, Germany
| | - Felix H. Schacher
- Laboratory of Organic
and Macromolecular
Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany
- Jena Center for Soft Matter
(JCSM), Friedrich Schiller University Jena, Philosophenweg 8, 07743 Jena, Germany
| | - Ulrich S. Schubert
- Laboratory of Organic
and Macromolecular
Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743 Jena, Germany
- Jena Center for Soft Matter
(JCSM), Friedrich Schiller University Jena, Philosophenweg 8, 07743 Jena, Germany
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Kumar N, Prabhakar A, Tikekar M, Singh S, Agrawal A. Blood flow in non-circular microchannel under pulsating condition. ACTA ACUST UNITED AC 2013. [DOI: 10.1260/1759-3093.4.1-2.33] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Cakmak G, Alkan FA, Korkmaz K, Saglam ZA, Karis D, Yenigun M, Ercan M. Blood viscosity as a forgotten factor and its effect on pulmonary flow. TRANSLATIONAL RESPIRATORY MEDICINE 2013; 1:3. [PMID: 27234385 PMCID: PMC6733503 DOI: 10.1186/2213-0802-1-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Accepted: 01/09/2013] [Indexed: 11/15/2022]
Abstract
Background The effect of smoking on blood viscosity is widely known. There are, however, few studies on the effect of blood viscosity on pulmonary circulation. Methods We aimed to observe the relationship between blood viscosity and pulmonary circulation among smokers and non-smokers. The study comprised 114 subjects in three groups: group 1, ex-smokers; group 2, smoked at least 10 packs/year and still smoking; group 3, never smoked. Blood viscosity (BV), pulmonary blood flow (PBF), and right ventricular systolic pressure (RVSP) were measured in all subjects. Results PBF was significantly lower in group 1 compared with group 3 (p < 0.05). BV in group 1 was significantly higher than group 3 (p < 0.05) while BV in group 2 was significantly higher than group 3 (p < 0.05). PBF in group 2 was significantly lower than group 3 (p = 0.01). Conclusions We believe that BV is a significant and forgotten factor that plays an important role in pulmonary and cardiovascular diseases. BV may affect PF even during the course of smoking, and before the clinical onset of chronic obstructive pulmonary disease (COPD). Therefore, individuals at risk of pulmonary hypertension could be detected earlier with a simple blood test.
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Affiliation(s)
- Gulfidan Cakmak
- Department of Chest Disease, Haseki Training and Research Hospital, Millet St Fatih, Istanbul, 34096, Turkey.
| | - Fatma Ates Alkan
- Department of Biophysics, Istanbul University Cerrahpasa Medical Faculty, Fatih, Istanbul, 34098, Turkey
| | - Kazim Korkmaz
- Department of Cardiology Disease, Haseki Training and Research Hospital, Millet St Fatih, Istanbul, 34096, Turkey
| | - Zuhal Aydan Saglam
- Department of Family Practitioners, Haseki Training and Research Hospital, Millet St Fatih, Istanbul, 34096, Turkey
| | - Denizhan Karis
- Department of Biophysics, Istanbul University Cerrahpasa Medical Faculty, Fatih, Istanbul, 34098, Turkey
| | - Mustafa Yenigun
- Department of Internal Disease, Haseki Training and Research Hospital, Millet St Fatih, Istanbul, 34096, Turkey
| | - Meltem Ercan
- Department of Biophysics, Istanbul University Cerrahpasa Medical Faculty, Fatih, Istanbul, 34098, Turkey
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25
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Yuruk K, Bartels SA, Milstein DMJ, Bezemer R, Biemond BJ, Ince C. Red blood cell transfusions and tissue oxygenation in anemic hematology outpatients. Transfusion 2011; 52:641-6. [PMID: 21883269 DOI: 10.1111/j.1537-2995.2011.03312.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND There is little clinical evidence that red blood cell (RBC) transfusions improve oxygen availability at the microcirculatory level. We tested the hypotheses that anemia in chronically anemic patients with relatively healthy microcirculation would be associated with low tissue hemoglobin (Hb) and tissue oxygenation levels and that these conditions would be improved after RBC transfusions. STUDY DESIGN AND METHODS Near-infrared spectroscopy (NIRS) was used to determine tissue oxygen saturation (StO(2)) and tissue Hb index (THI; an index of the amount of Hb in the NIRS measurement volume) in the thenar eminence and sublingual tissue before and 30 minutes after RBC transfusions in 20 chronically anemic hematology outpatients. Data are presented as median (25%-75%). RESULTS The patients received three (two to three) bags of RBCs in saline-adenine-glucose-mannitol with an age of 21 (7-21) days, which was infused intravenously at the rate of 0.7 bag/hr. RBC transfusions significantly increased hematocrit level from 26% (24%-28%) to 32% (30%-34%; p < 0.0001), Hb level from 8.2 (7.6-8.9) g/dL to 11.0 (9.9-11.8) g/dL (p < 0.0001), whole blood viscosity from 3.4 (3.1-3.5) mPa/sec to 4.2 (4.0-4.5) mPa/sec (p < 0.0001), thenar StO(2) from 81% (80%-84%) to 86% (81%-89%; p = 0.002), thenar THI from 11.2 (9.3-13.3) AU to 13.7 (9.7-15.3) AU (p = 0.024), sublingual StO(2) from 86% (81%-89%) to 91% (86%-92%; p < 0.0001), and sublingual THI from 15.2 (13.0-17.4) AU to 17.2 (13.5-19.7) AU (p = 0.040). CONCLUSION Although anemia in chronically anemic hematology outpatients was not associated with low StO(2) and THI levels, RBC transfusions were successful in improving these variables.
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Affiliation(s)
- Koray Yuruk
- Department of Translational Physiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.
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Increased arterial oxygen content by artificial haemoglobin induces a decrease in regional cerebral blood flow and decreased regional cerebral oxygen delivery. Eur J Anaesthesiol 2009; 26:245-52. [PMID: 19244699 DOI: 10.1097/eja.0b013e328324b76b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND OBJECTIVE Under physiological conditions, cerebral oxygen delivery is kept constant by adaptation of the regional cerebral blood flow (CBF) in relation to the oxygen content. So far, decreases of the regional CBF induced by a higher arterial oxygen content have been produced under hyperbaric or hyperviscous conditions. We tested whether local CBF is also reduced by a high haemoglobin (Hb) concentration at a normal haematocrit (Hct). METHODS Compared with controls (n=8), Hb content was increased to 19 g dl(-1) in conscious rats by isovolaemic replacement of the plasma fraction with an artificially high Hb solution (Hb-based oxygen carriers; HH group, n=8). In another group (n=8), Hct was decreased by isovolaemic exchange with an Hb-based oxygen carrier resulting in a normal Hb content (NH group). Mean and regional CBF was measured by iodo-[(14)C]-antipyrine autoradiography. Oxygen delivery was calculated from arterial oxygen content and CBF. RESULTS Compared with the controls (Hb 15.3 g dl(-1), Hct 0.44), mean CBF was lower in the HH (Hb 20.3 g dl(-1), Hct 0.44) group by 23% (P < or = 0.05), but remained unchanged in the NH group (Hb 15.0 g dl(-1), Hct 0.29). On a local level, hyperoxygenation reduced CBF in 22 out of 39 brain regions. In the NH group mean CBF was unchanged, whereas local CBF was higher in 10 areas. In both groups, overall cerebral oxygen delivery was unchanged compared with the control group. Locally though, high arterial Hb content decreased oxygen delivery in one-third of the brain structures. CONCLUSION Whereas the overall cerebral oxygen delivery in the brain is maintained during hyperoxygenation and haemodilution, local oxygen delivery is decreased by high arterial Hb content in some brain regions.
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