Background And Objective: Blood oxygen concentration decrease may be associated with haemostatic impairments. We aimed to study the effect of oxygen decrease in a rabbit model of thrombosis and bleeding.
Methods: A total of 44 rabbits were anaesthetized, ventilated and monitored for blood pressure, blood arterial gas, temperature and carotid blood flow. The Folts model was used: a stenosis (75%) and an injury were carried out on the carotid artery, inducing thrombosis. Blood flow decreased as thrombus size increased until the pressure gradient was such that the thrombus was released and local arterial blood flow was suddenly restored. This is known as a cyclic flow reduction. After counting baseline cyclic flow reductions during a 20-min period (P1), rabbits were randomized blindly to one of three groups: hyperoxic, FiO2=100%; normoxic, FiO2 was decreased to obtain a PaO2 between 80 and 120 mmHg; hypoxic, PaO2 < 80 mmHg. Then CFRs were recorded over a second 20-min period (P2). At the end of the experiment, a hepatosplenic section was done and the amount of blood loss was recorded. After each period, the following parameters were measured: blood gas, ear-immersion bleeding time, haemoglobin, platelet count, prothrombin time, activated partial thromboplastin time and fibrinogen.
Results: Oxygen decrease during hypoxic and normoxic periods was associated with a decrease in cyclic flow reductions. Bleeding time increased in the hypoxic group unless hepatosplenic bleeding remained stable. A slight increase in activated partial thromboplastin time was observed in the normoxic and hypoxic groups.
Conclusion: An abrupt decrease in oxygen administration was responsible for an antithrombotic effect. Increase in bleeding time occurred during hypoxia. No clinically relevant variation of any haemostasis parameters was observed.
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http://dx.doi.org/10.1017/S0265021508004390 | DOI Listing |
Crit Care Sci
January 2025
Department of Physical Therapy, Universidade Federal de Uberlândia - Uberlândia (MG), Brazil.
Objective: To investigate the effects of lycopene supplementation on inflammation, lung histopathology and systemic DNA damage in an experimentally induced lung injury model, ventilated by conventional mechanical ventilation and high-frequency oscillatory ventilation, compared with a control group.
Methods: Fifty-five rabbits sampled by convenience were supplemented with 10mg/kg lycopene for 21 days prior to the experiment. Lung injury was induced by tracheal infusion of warm saline.
Crit Care Sci
January 2025
Anaesthesiology and Critical Care, All India Institute of Medical Sciences - Jodhpur, India.
Objective: Although the efficacy of high-flow nasal oxygen therapy in delaying or avoiding intubation in patients with hypoxemic respiratory failure has been studied, its potential for facilitating early weaning from invasive mechanical ventilation remains unexplored.
Methods: In this randomized controlled trial, 80 adults with acute hypoxemic respiratory failure requiring invasive mechanical ventilation for > 48 hours were enrolled and divided into two groups: conventional weaning and early weaning via high-flow nasal oxygen. In the conventional weaning group, the spontaneous breathing trial was performed after the PaO2/FiO2 ratio was ≥ 200, whereas in the high-flow nasal oxygen group, the spontaneous breathing trial was conducted earlier when the PaO2/FiO2 ratio was 150 - 200.
PLoS One
January 2025
Precision Laboratory of Vascular Medicine, Shanxi Cardiovascular Hospital Affiliated Shanxi Medical University, Taiyuan, PR China.
Background: Myocardial ischemia-reperfusion injury (MIRI) is an important complication in the treatment of heart failure, and its treatment has not made satisfactory progress. Nitroxyl (HNO) showed protective effects on the heart failure, however, the effect and underlying mechanism of HNO on MIRI remain largely unclear.
Methods: MIRI model in this study was established to induce H9C2 cell injury through hypoxia/reoxygenation (H/R) in vitro.
Mar Biotechnol (NY)
January 2025
Marine Ecology Research Center, Ministry of Natural Resources, First Institute of Oceanography, Qingdao, 266061, China.
Planiliza haematocheilus, a teleostan species noted for its ecological adaptability and economic significance, thrives in both freshwater and marine environments. This study presents a novel chromosome-level genome assembly through Hi-C, PacBio CCS, and Illumina sequencing methods. The assembled genome has a final size of 651.
View Article and Find Full Text PDFIn Vitro Model
February 2024
Faculty of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-Cho, Koganei, Tokyo 184-8588 Japan.
Unlabelled: Engineered three-dimensional (3D) tissue culture platforms are useful for reproducing and elucidating complex in vivo biological phenomena. Spheroids, 3D aggregates of living cells, are produced based on physicochemical or microfabrication technologies and are commonly used even in cancer pathology research. However, conventional methods have difficulties in constructing 3D structures depending on the cell types, and require specialized techniques/lab know-how to reproducibly control the spheroid size and shape.
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