filip de somer | Ghent University (original) (raw)

Papers by filip de somer

Scientific Reports, Jul 15, 2019

BMC Anesthesiology, Nov 28, 2017

Kidney International Reports, Nov 1, 2019

BMC Medical Education, Nov 14, 2022

Intensive Care Medicine Experimental, Oct 1, 2015

Journal of the American College of Cardiology, Jul 1, 2012

This study investigates the contribution of infundibular versus pulmonary valve (PV) dysfunction ... more This study investigates the contribution of infundibular versus pulmonary valve (PV) dysfunction on right ventricular (RV) function in a porcine model. Background Clinical outcome after repair of tetralogy of Fallot is determined by the adaptation of the right ventricle to the physiological sequelae of the right ventricular outflow tract (RVOT) reconstruction. Recent surgical techniques are pursuing a PV-versus infundibulum-sparing approach.

Acta Cardiologica, Dec 1, 2011

Objectives The objective of this study was to investigate the patient characteristics and outcome... more Objectives The objective of this study was to investigate the patient characteristics and outcomes in 1406 patients undergoing intra-aortic balloon pump (IABP) counterpulsation. Methods Between 1998 and 2008, 1406 consecutive patients were recorded in a prospective database. Based on the main clinical indication for IABP use, we defi ned 3 groups: group A, 630 cases of coronary ischaemia or infarction without serious left ventricular (LV) dysfunction; group B, 466 patients with left ventricular failure or cardiogenic shock; group C, 310 patients where IABP was used for miscellaneous procedures such as weaning from cardiopulmonary bypass or during high-risk angioplasty or surgery. Results Global mortality was 28% (n = 390), with a signifi cant diff erence between group A (15%, n = 95) and group B (41%, n = 191) (P < 0.001). Mortality in group C was 34% (n = 104). Most insertions were done in the catheterization laboratory (n = 943) with subsequent mortality of 23% whereas 199 balloons were inserted in the operation room with 34% mortality. 170 balloons inserted in the intensive care unit resulted in 46% mortality (P < 0.001). Major IABP-induced complications were 6.8% with no statistical diff erences between the three groups. Advanced age, left ventricular failure and low BMI were identifi ed as prognostic risk factors for early mortality. Conclusions IABP deployed at an early clinical stage yields the best results, especially for acute coronary patients with preserved LV function whereas LV failure and late insertion result in worse outcome.

Perfusion, May 1, 1998

At present, air handling of a membrane oxygenator is generally studied by using an ultrasonic sou... more At present, air handling of a membrane oxygenator is generally studied by using an ultrasonic sound bubble counter. However, this is not a quantitative method and it does not give any information on where air was entrapped in the oxygenator and if it eventually was removed through the membrane for gas exchange. The study presented here gives a novel technique for the determination of the air-handling characteristics of a membrane oxygenator. The study aimed at defining not only the amount of air released by the oxygenator, but also the amount of air trapped within the oxygenator and/or removed through the gas exchange membrane. Two neonatal membrane oxygenators without the use of an arterial filter were investigated: the Polystan Microsafe and the Dideco Lilliput. Although the air trap function of both oxygenators when challenged with a bolus of air was similar, the Microsafe obtained this effect mainly by capturing the air in the heat exchanger compartment while the Lilliput did remove a large amount of air through the membrane. In conclusion, the difference in trap function was most striking during continuous infusion of air. Immediate contact with a microporous membrane, avoidance of high velocities within the oxygenator, pressure drop, transit time and construction of the fibre mat all contribute to the air-handling characteristics of a membrane oxygenator.

Heart Surgery Forum, Apr 1, 2010

Background Scarce data are available to guide cefazolin dosing in children undergoing cardiac sur... more Background Scarce data are available to guide cefazolin dosing in children undergoing cardiac surgery with cardiopulmonary bypass (CPB). Objectives Intermediate results The objective of this trial is to derive a model-based dosing regimen for cefazolin in this patient population.

Objectives: Xenogenic extracellular heart valve matrices have been suggested as scaffolds for tis... more Objectives: Xenogenic extracellular heart valve matrices have been suggested as scaffolds for tissue engineering. However, these matrices need to be cross-linked in order to mitigate immune reaction. Moreover, cross-linked matrices should be repopulated with the appropriate cell type to create a viable and biocompatible valve with the ability to grow, repair and remodel. The aim of this study was to repopulate gamma-radiated matrices with human mesenchymal stem cells (hMSCs). Methods: Porcine matrices were prepared by a detergent-enzymatic treatment and were exposed to 1-10 Gy gamma-irradiation in 0.9% NaCl. Tensile strength and pore size of the matrices was evaluated. hMSCs were isolated from bone marrow and differentiated into myofibroblasts by the use of TGF-s. The irradiated matrices were seeded with myofibroblasts and grown in vitro in a dynamic system (bioreactor). A natural cocktail of growth factors from autologous platelets was added to the culture medium. Analysis of the matrices included histology, immunohistology and transmission electron microscopy (TEM). Results: Gamma-radiation was fine-tuned in order to maintain a minimum pore size of 10 µm to allow cell in-growth (3-6 Gy). Tensile strength increased in irradiated matrices at the expense of elasticity. Immunohistochemical analysis showed active myofibroblasts positive for vimentin and desmin. Formation of stress fibres was confirmed by positive α-SMA staining. Microscopic evaluation of the cultivated matrices showed mesenchymal cell in-growth. Conclusions: Repopulating of gamma-radiated matrices was feasible using an autologous cocktail of growth factors. Cross-linked xenogenic matrices should retain a defined porosity in order to be repopulated with the appropriate cell type

Veterinary medicine and science, May 4, 2023

BackgroundActivated clotting times (ACTs) are used to screen for coagulopathies and monitor hepar... more BackgroundActivated clotting times (ACTs) are used to screen for coagulopathies and monitor heparin therapy.ObjectivesTo determine a reference interval (RI) for ACT in dogs using a point‐of‐care analyser, to quantify intra‐subject within‐ and between‐day variability, to quantify analyser reliability and inter‐analyser agreement and to study the influence of a delay in measurement.MethodsForty‐two healthy dogs were included. Measurements were performed on fresh venous blood using the i‐STAT 1 analyser. The RI was determined using the Robust method. Intra‐subject within‐day variability and between‐day variability were quantified between baseline and 2 h (n = 8) or 48 h (n = 10) later. Analyser reliability and inter‐analyser agreement were studied by duplicate measurements (n = 8) on identical analysers. The influence of measurement delay was studied before and after a delay of one analytical run (n = 6).ResultsMean, lower and upper reference limits for ACT were 92.9 ± 9.1, 74.4 and 111.2 s, respectively. Coefficients of variation of intra‐subject within‐ and between‐day variability were 8.1% and 10.4%, respectively, resulting in a significant between‐day measurement difference. Analyser reliability assessed by the intraclass correlation coefficient and coefficient of variation were 0.87% and 3.3%, respectively. Significantly lower ACT values were observed after a measurement delay compared to direct analysis.ConclusionsOur study provides an RI for ACT in healthy dogs using the i‐STAT 1 and suggests low intra‐subject within‐ and between‐day variability. Analyser reliability and inter‐analyser agreement were good; however, analysis delay and between‐day differences could significantly influence ACT results.

European Journal of Cardio-Thoracic Surgery, 2020

OBJECTIVES The aim of this study was to investigate the effect of short- versus long-segment aort... more OBJECTIVES The aim of this study was to investigate the effect of short- versus long-segment aortic stiffness and stenosis on ventriculo-arterial interaction in a porcine model of coarctation repair. METHODS Short–long aortic stiffness was created by transection/suture [coarctation (CoA) suture, n = 6] and stenting (stent, n = 5) of the proximal descending aorta. Short–long aortic stenosis was achieved by wrapping a prosthetic graft around the aorta to 1/3-circumference reduction, over a segment length of 1 cm (CoA suture stenosis, n = 5) and 4.5 cm (stent stenosis, n = 6). After 3 months, aortic pressure-flow haemodynamics, aortic distensibility by intravascular ultrasound and left ventricular performance by pressure–volume loops were compared to a Sham group (n = 5) at baseline and during dobutamine administration. RESULTS The aortic impedance increased with 30.3 (12.6%) and 41.3 (20.9%) (P < 0.001) in CoA stenosis and stent stenosis during inotropic response. Impaired haemodyn...