Search results for "Flow"

High flow nasal therapy in immunocompromised patients with acute respiratory failure: A systematic review and meta-analysis.

2019

Abstract Purpose The role of high-flow nasal therapy (HFNT) as compared to conventional oxygen therapy (COT) in immunocompromised patients admitted to intensive care unit (ICU) with acute respiratory failure (ARF) remains unclear. We conducted a systematic review and meta-analysis in order to address this issue. Methods We searched PubMed, Medline and Embase until November 7th, 2018. Randomized controlled trials (RCTs), non-randomized prospective and retrospective evidence were selected. Observational studies were considered for sensitivity analysis. Primary outcome was mortality rate; intubation rate was a secondary outcome. Results We included four studies in the primary analysis: one RCT…

Primary biliary cholangitis in Spain. Results of a Delphi study of epidemiology, diagnosis, follow-up and treatment.

2018

RESUMEN Introducción: la colangitis biliar primaria (CBP) es una enfermedad rara, de la que existe información limitada en España sobre su epidemiología y manejo en la práctica clínica habitual. Objetivos: conocer la epidemiología, flujo del paciente, diagnóstico, seguimiento y tratamiento de la CBP en España. Métodos: revisión de la literatura y estudio siguiendo la metodología Delphi con participación de 28 especialistas en dos rondas de consulta y un taller de validación de resultados presencial. Resultados: existen, aproximadamente, 9.400 pacientes con CBP en España, con una incidencia anual de entre 0,51 y 3,86 casos/100.000 habitantes, aunque el margen de error se presupone alto dada …

The influence of isolated small nerve fibre dysfunction on microvascular control in patients with diabetes mellitus

2001

Aim The aim of the study was to investigate the influence of isolated small nerve fibre dysfunction on microvascular skin blood flow and transcutaneous oxygen tension in patients with diabetes mellitus. Methods  Small nerve fibre dysfunction was assessed by the measurement of thermal and pain perception thresholds. Patients with evidence of large fibre disturbances as evaluated by means of vibration perception threshold were excluded from the study. Microvascular blood flow was investigated with laser-Doppler-fluxmetry (LDF) following stimulation with acetylcholine and mild thermal injury. Results  Diabetic patients with small nerve fibre injury showed a significantly reduced increase in th…

Aussagefähigkeit und Stellenwert von bildgebender Diagnostik und Duplexsonographie bei Neugeborenen mit nekrotisierender Enterokolitis

1994

In this prospective study 101 sonographic examinations of superior mesenteric artery blood flow velocities, indices and blood flow volume were consecutively performed in 41 newborn to diagnose necrotising enterocolitis (NEC). Intramural and portal venous gas was also estimated. The artifacts of air in the AMS and the portal system were examined in an experimental study. The results of sonography and abdominal radiography were equivalent in the case of definitely established NEC, portal venous gas being more sensitive to detection by sonography. Abdominal radiography was indicated as the primary examination in case of a clearly identified clinical course. Sonography should be performed so th…

Left ventricular non-compaction cardiomyopathy in children: Is segmental fibrosis the cause of tissue Doppler alterations and of EF reduction?

2009

Noncompaction of the ventricular myocardium (LVNC) is a rare congenital cardiomyopathy resulting from an arrest in normal endomyocardial embryogenesis. In 2002 Jenni et al. [Jenni R, Wyss CA, Oechslin EN, Kaufmann PA. Isolated ventricular noncompaction is associated with coronary microcirculatory dysfunction. J Am Coll Cardiol 2002; 39:450-454.] reported a microvascular dysfunction in 12 patients affected by non compaction: areas of restricted myocardial perfusion have been documented by scintigraphy, suggesting a reduction of Coronary flow reserve. McMahon et al reported in a recent article a reduction of TD velocities in children with noncompaction of the left ventricle, compared with nor…

Mathematical Modelling of Local Regulation of Blood Flow by Veno-Arterial Diffusion of Vasoactive Metabolites

1997

It is widely accepted that vasoactive substances which are consumed or produced by tissue metabolism play a role in the adjustment of local perfusion rate to the metabolic needs of the tissue. In order to evoke a response of the vascular system, these substances — in the following for simplicity denoted by “vasodilators” even though oxygen, for example, is a vasoconstrictor — need to get into close contact with the small arterioles which represent the most powerful effectors in perfusion control. On the other hand, tissue sites in which supply with nutrients is most critical (“lethal corners”) and in which a vasodilator signal may be generated earliest, are located hundreds of µm away from …

Effects of endothelin-1 on the cerebrovascular bed of the goat.

1991

Abstract The aim of the present study was to analyze the effects of endothelin-1 (ET-1) in the cerebrovascular bed of the goat, the importance of endothelial integrity and the contribution of extracellular Ca2+ to these responses. We measured isometric tension and 45Ca2+ uptake in isolated middle cerebral arteries, and cerebral blood flow (CBF) in unanesthetized animals. ET-1 elicited concentration-dependent contractions which were potentiated in arteries without endothelium. Ca2+-free medium and nicardipine inhibited, and Bay K 8644 potentiated the ET-1-induced contractions. ET-1 enhanced 45Ca2+ uptake in isolated arteries. Injections of ET-1 directly into the cerebral circulation decrease…

Angiotensin II induces leukocyte-endothelial cell interactions in vivo via AT(1) and AT(2) receptor-mediated P-selectin upregulation.

2000

Background —Angiotensin II (Ang II) plays a critical role in the development of vascular lesions in hypertension, atherosclerosis, and several renal diseases. Because Ang II may contribute to the leukocyte recruitment associated with these pathological states, the aim of the present study was to assess the role of Ang II in leukocyte–endothelial cell interactions in vivo. Methods and Results —Intravital microscopy of the rat mesenteric postcapillary venules was used. Sixty minutes of superfusion with 1 nmol/L Ang II induced a significant increase in leukocyte rolling flux (83.8±20.7 versus 16.4±3.1 cells/min), adhesion (11.4±1.0 versus 0.8±0.5 cells/100 μm), and emigration (4.0±0.7 versus …

P4‐266: Decreases in cerebral blood flow are associated with Aβ status in preclinical Alzheimer's disease

2015

In-vitro assessment of centrifugal pumps for ventricular assist.

1990

Currently two major types of centrifugal pumps are commercially available for ventricular assist: the Biomedicus-cone (Group I) and the Centrimed-impeller pump (now Sarns 3M) (Group II). To compare them for blood trauma and hemolysis, an in-vitro experiment was designed with a Stockert roller pump as a standard control (Group III). The in-vitro circuit was constructed consisting of a pump head, electromagnetic flow probe, polyvinyl chloride tubing and a reservoir, identical for all groups. Human ACD blood was used for priming and was circulated with a flow rate of 2 L/min for 24 h. Blood samples were taken at 0, 1, 3, 6, 12, and 24 h and zero control values were subtracted from the resultin…