Search results for "Perfusion"

Development and Long-Term Follow-Up of an Experimental Model of Myocardial Infarction in Rabbits

2020

Simple Summary Ischemic heart disease is one of the leading causes of death. A series of processes occur during acute myocardial infarction that contribute to the development of ventricular dysfunction, with subsequent heart failure and ventricular arrhythmias, which account for most episodes of sudden cardiac death in these patients. These complications are associated with the adverse cardiac remodeling that occurs during the healing process following an acute episode. The remodeling causes the appearance of a substrate that can trigger life-threatening arrhythmias, such as tachycardia and/or ventricular fibrillation. The development of experimental models for analyzing the basic mechanism…

A comparison of micropore membrane inlet mass spectrometry–derived pulmonary shunt measurement with riley shunt in a porcine model

2009

The multiple inert gas elimination technique was developed to measure shunt and the ratio of alveolar ventilation to simultaneous alveolar capillary blood flow in any part of the lung (V(A)'/Q') distributions. Micropore membrane inlet mass spectrometry (MMIMS), instead of gas chromatography, has been introduced for inert gas measurement and shunt determination in a rabbit lung model. However, agreement with a frequently used and accepted method for quantifying deficits in arterial oxygenation has not been established. We compared MMIMS-derived shunt (M-S) as a fraction of total cardiac output (CO) with Riley shunt (R-S) derived from the R-S formula in a porcine lung injury model.To allow a …

FVIII production by human lung microvascular endothelial cells

2006

While extrahepatic factor VIII (FVIII) synthesis suffices for hemostasis, the extrahepatic production sites are not well defined. We therefore investigated the ability of the human lungs to produce FVIII. Lungs from heart-beating donors who were declined for transplantation were perfused and ventilated in an isolated reperfusion model for 2 hours. A progressive accumulation of FVIII and von Willebrand factor (VWF) was recorded in the perfusion medium in 3 of 4 experiments. By contrast, factor V, fibrinogen, and immunoglobulin G (IgG) levels remained constant during the perfusion period, indicating that the accumulation of FVIII and VWF was not due to diffusion from the intercellular medium …

Oxidative lung injury correlates with one-lung ventilation time during pulmonary lobectomy: a study of exhaled breath condensate and blood.

2015

OBJECTIVES: During lung lobectomy, the operated lung is collapsed and hypoperfused; oxygen deprivation is accompanied by reactive hypoxic pulmonary vasoconstriction. After lung lobectomy, ischaemia present in the collapsed state is followed by expansion–reperfusion and lung injury attributed to the production of reactive oxygen species. The primary objective of this study was to investigate the time course of several markers of oxidative stress simultaneously in exhaled breath condensate and blood and to determine the relationship between oxidative stress and one-lung ventilation time in patients undergoing lung lobectomy. METHODS: This single-centre, observational, prospective study includ…

New 3-zone hybrid graft : First-in-man experience in acute type I dissection

2019

Abstract Objective Acute type I aortic dissection (AAD) represents a surgical emergency with time-dependent evolving complications. Frozen elephant trunk (FET) enables false lumen exclusion downstream but is still debated in AAD due to its greater dimension of surgery. To combine the benefits of fast proximal repair with the FET benefits, a 3-zone hybrid graft was developed consisting of an ascending polyester portion, an arch noncovered stent, and a descending stent graft. Mid-term results of this new technique are presented. Methods A total of 6 patients (age mean 69 years) with type I AAD in critical status (Penn classification B n = 5, BC n = 1) were operated between July 2016 and April…

Intraoperative neuroprotective drugs without beneficial effects? Results of the German Registry for Acute Aortic Dissection Type A (GERAADA).

2013

OBJECTIVES: Cerebral protection during acute aortic dissection Type A (AADA) surgery may be affected by perfusion strategies and ischaemic protective drugs. METHODS: We analysed the impact of intraoperative barbiturate, steroid and mannitol use and adjunctive cerebral perfusion (CP), on 30-day mortality and new postoperative mortality-corrected permanent neurological dysfunction (PNDmc) in the German Registry for Acute Aortic Dissection Type A. RESULTS: Two thousand one hundred and thirty-seven AADA patients were registered over a 4-year period. The overall 30-day mortality was 16.9%, and the overall rate of PNDmc was 10.0%. A total of 48% of patients received no neuroprotective drugs (cont…

Comparative efficacy of levocetirizine, desloratadine, clemastine, kvifenadine and sekvifenadine on histamine prick test induced weal reaction, blood…

2007

Cardioprotective effects of the serine protease inhibitor aprotinin after regional ischemia and reperfusion on the beating heart.

2002

AbstractObjective: Early coronary reperfusion of the ischemic myocardium is a desired therapeutic goal to preserve myocardium. However, reperfusion itself contributes to an additional myocardial injury (ie, reperfusion injury), which has been attributed to neutrophil infiltration with subsequent release of proteases and oxygen-derived radicals. We studied the effects of the serine protease inhibitor aprotinin (Trasylol) on myocardial ischemia and reperfusion in a rat model. Methods: The effects of aprotinin (5000 and 20,000 U/kg) were examined in vivo in a rat model of regional myocardial ischemia (20 minutes) and long-term reperfusion (24 hours). Cardioprotecive effects were determined by …

Anatomic and flow dynamic considerations for safe right axillary artery cannulation.

2013

Objectives Neuroprotection is of paramount interest in cardiac surgery. Right axillary artery cannulation is well established in aortic surgery because it significantly improves survival and outcome, but malperfusion of the right brain after direct cannulation has been reported. Anatomically, 4 vessel segments are potentially amenable for cannulation of the subclavian and axillary arteries. Clinical studies vary widely in dissection sites and cannulation techniques. We investigated critical flow dynamics in the right brain caused by arterial inflow after direct cannulation and specified cannulation positions that provide optimal cerebral perfusion. Methods Distances from the lateral margin …

Particulate Matter Contamination of Intravenous Antibiotics Aggravates Loss of Functional Capillary Density in Postischemic Striated Muscle

2002

Through the increased use of less expensive and counterfeit medicines, the contamination of parenteral fluids and drugs by particulate matter poses an increasing health hazard worldwide. However, the mechanism of action of such contamination has never been conclusively demonstrated. We have systemically injected the particles contained in three different 1-g preparations of the antibiotic cefotaxime into hamsters and visualized the functional capillary density in striated skin muscle, using intravital fluorescence microscopy. Injection of particles from either of the three preparations did not affect capillary perfusion in normal muscle (n = 3 hamsters, each). However, injection of particle…