Publications by authors named "Mechelen H"

Purpose: Long-term outcomes of critical illness may be affected by duration of critical illness and intensive care. We aimed to investigate differences in mortality and morbidity after short (<8 days) and prolonged (≥8 days) intensive care unit (ICU) stay.

Methods: Former EPaNIC-trial patients were included in this preplanned prospective cohort, 5-year follow-up study.

View Article and Find Full Text PDF

Purpose: Muscle weakness in long-stay ICU patients contributes to 1-year mortality. Whether electrophysiological screening is an alternative diagnostic tool in unconscious/uncooperative patients remains unknown. We aimed to determine the diagnostic properties of abnormal compound muscle action potential (CMAP), sensory nerve action potential (SNAP), and spontaneous electrical activity (SEA) for Medical Research Council (MRC)-defined weakness and their predictive value for 1-year mortality.

View Article and Find Full Text PDF

Rationale: Intensive care unit (ICU)-acquired weakness is a frequent complication of critical illness. It is unclear whether it is a marker or mediator of poor outcomes.

Objectives: To determine acute outcomes, 1-year mortality, and costs of ICU-acquired weakness among long-stay (≥8 d) ICU patients and to assess the impact of recovery of weakness at ICU discharge.

View Article and Find Full Text PDF

Objective: Muscle weakness often complicates critical illness and is associated with increased risk of morbidity, mortality, and limiting functional outcome even years later. To assess the presence of muscle weakness and to examine the effects of interventions, objective and reliable muscle strength measurements are required. The first objective of this study is to determine interobserver reliability of handheld dynamometry.

View Article and Find Full Text PDF

Background: A new beta 3-adrenoceptor (beta3-AR) has been shown to mediate peripheral vasodilation. This study was conducted to evaluate effects of the beta3-AR agonist, SR58611 in normal and hypertensive dogs.

Materials And Methods: In protocol 1, SR58611 was infused in normal dogs after placebo, after beta1/beta2 blockade with nadolol, after beta1/beta2/beta3 blockade with bupranolol and after combined autonomic blockade (CAB).

View Article and Find Full Text PDF

Background: As endothelin-1 exerts positive inotropic effects, the present study evaluated whether the hypotensive effects of the endothelin-1 receptor antagonist bosentan were partially related to a decrease in myocardial performance.

Methods: In group I, eight anaesthetized open-chest dogs with perinephritic hypertension received four cumulative doses of bosentan (B1-B4). In group II, eight animals received the same doses of bosentan after autonomic blockade.

View Article and Find Full Text PDF

Objective: To evaluate whether the cumulative hypotensive effect of the endothelin-1 receptor antagonist bosentan, previously demonstrated in the presence of an angiotensin converting enzyme inhibitor, persists under angiotensin II receptor blockade with losartan.

Design: The model of hypertension was canine renovascular hypertension (Page hypertension).

Methods: Ten conscious dogs, studied on two occasions, were administered losartan (a 0.

View Article and Find Full Text PDF

We studied effects of enalaprilat and L-158,809, an angiotensin II type-1 receptor antagonist, on left ventricular (LV) diastolic relaxation in 11 normal control dogs and 16 LV hypertrophied (LVH) dogs with perinephritic hypertension. At baseline, LV systolic and end-diastolic pressures and end-systolic elastance were increased in the LVH group (all P < 0.01 vs.

View Article and Find Full Text PDF

Background: Endothelin-1 (ET-1) may play a role in hypertension. ET-1 receptor antagonism by bosentan lowers blood pressure in hypertension. We evaluated whether the effect of bosentan is still observed under ACE inhibitors (ACEI).

View Article and Find Full Text PDF

Objective: Angiotensin II has been suggested to be involved in the pathogenesis of diastolic dysfunction in left ventricular hypertrophy (LVH). The purpose of this study was to asses the effects of enalaprilat and L-158,809, an angiotensin II type-1 receptor antagonist, on LV diastolic function in 16 normal control dogs and 20 LVH dogs with perinephritic hypertension.

Methods: LV hemodynamics was studied before and after intravenous injection of enalaprilat (0.

View Article and Find Full Text PDF

Octreotide inhibits the secretion of several hormones and exerts vasopressor effects. To clarify the mechanism of atrial natriuretic factor (ANF) secretion and to assess the cardiovascular effects of octreotide in relation to changes in vasoactive peptide secretion, four groups of conscious dogs were studied: group I (n = 11) received saline infusion after placebo, group II (n = 10), the same infusion after octreotide, group III (n = 10), placebo only and group IV (n = 10) octreotide injection only. Saline (10% body wt) was infused over 40 min after subcutaneous injection of placebo or octreotide (1 microgram/kg).

View Article and Find Full Text PDF

Background: Endothelin-1, a vasoconstrictive peptide released by endothelium, may be involved in the pathophysiology of hypertension. The goal of the present study was to evaluate the role of endogenous endothelin-1 in renal hypertension in dogs. The model of hypertension consisted of silk tissue wrapping of the left kidney, which produced hypertension associated with perinephritis after 6 to 8 weeks.

View Article and Find Full Text PDF

We assess hemodynamic, vascular, and hormonal effects of endothelin-1 (ET-1) at pathophysiologic levels on normal and ischemic myocardium. Thirty conscious chronically instrumented dogs were studied before, during, and after a 10-min coronary artery occlusion (CAO) performed either during ET-1 infusion (2.5 ng/kg.

View Article and Find Full Text PDF

The purpose of this study was to examine the effects of endothelin-1 (ET-1) on "diastolic stunning" in the postischemic myocardium. In 14 conscious dogs receiving either placebo (n = 7) or ET-1 (2.5 ng.

View Article and Find Full Text PDF

To evaluate the role of calcium in volume-induced secretion of atrial natriuretic factor (ANF), effects of verapamil and endothelin-1 (ET-1), both known to influence free intracellular calcium, were studied during saline infusion in seven conscious instrumented dogs. Fifteen minutes after intravenous injection of placebo or verapamil (0.25 mg/kg) or during continuous ET-1 infusion (at 5 ng.

View Article and Find Full Text PDF

Twenty-six patients with mild to moderate heart failure were studied to determine the effects of epinine infusion (at a rate producing plasma levels similar to those measured after oral administration of 100 mg of the prodrug ibopamine) on left ventricular (LV) function (14 patients), and coronary flow and circulating catecholamines (12 patients). The only significant hemodynamic change at an infusion rate of 0.5 microgram/kg/min was a 9% (p less than 0.

View Article and Find Full Text PDF

Background: Increased plasma concentrations of endothelin-1, a potent vasoconstrictor produced by the endothelium, have been reported in various pathological conditions. This study was conducted to evaluate effects of endothelin-1 at pathophysiological and pharmacological plasma concentrations.

Methods And Results: Endothelin-1 was infused at increasing doses (2.

View Article and Find Full Text PDF

To determine if alterations in regional coronary vascular resistance could occur in the type of myocardial ischemia present in severe angina pectoris, regional perfusion and function were studied in 35 conscious sedated dogs. A stenosis producing severe hypokinesia of the perfused segment was created for 2 h on the left anterior descending coronary artery and 10 episodes of 1 min of high demand ischemia (atrial pacing at a rate sufficient to induce dyskinesia in the hypoperfused segment) were superimposed before reperfusion. The dogs were randomized into three treatment groups: control (n = 13), dipyridamole (n = 10) or WEB-2086 (n = 12), an antagonist of the effects of the endogenous platelet-activating factor.

View Article and Find Full Text PDF

Detailed left ventricular haemodynamic investigations were performed in eight patients with New York Heart Association (NYHA) Class II heart failure, eight with NYHA Class III heart failure with an ejection fraction less than 35%, and six with severe heart failure. Xamoterol (200 mg b.d.

View Article and Find Full Text PDF

Acute intravenous administration of the new beta 1-adrenergic receptor partial agonist xamoterol lowers left ventricular end-diastolic pressure and improves the isovolumic indexes of inotropic state and relaxation. To determine if these hemodynamic changes were maintained after prolonged administration, the dose-response relation to cumulative doses of xamoterol was determined in a group of 14 patients with mild (n = 6)-to-serve (n = 8) ischemic left ventricular dysfunction. These patients had been treated with xamoterol (200 mg, b.

View Article and Find Full Text PDF

Myocardial oxygen uptake and an index of mechanical left ventricular efficiency were determined in basal conditions or during prolonged therapy with the new beta 1-adrenoceptor partial agonist xamoterol in 16 patients with mild to moderate ischemic heart failure. During xamoterol therapy, left ventricular end-diastolic pressure decreased from 24.4 +/- 6.

View Article and Find Full Text PDF

The purpose of this study was to examine the time course of the changes in left ventricular inotropic state after intravenous pimobendan administration. In conscious dogs, cumulative doses of 1 and 2.5 mg of pimobendan significantly increased heart rate and the isovolumic indices of inotropic state and relaxation.

View Article and Find Full Text PDF

Pimobendan (UD-CG 115) is a long-acting positive inotropic drug with arterio- and venodilator properties. To determine to what extent this new agent is able to affect contractile function in previously ischemic areas of the left ventricle (LV), the effects of pimobendan on global and regional LV function were studied in eight conscious dogs, 2 days after a 2-h coronary occlusion followed by reperfusion. Before pimobendan, percentage of systolic shortening and mean velocity of shortening were lower in reperfused segments than in control areas (0.

View Article and Find Full Text PDF

The effects of atriopeptin III (AP III) on the left ventricular and renal functions were studied in thirteen chronically instrumented conscious dogs and compared to those of the solvent (saline). In the normovolaemic state, an AP III infusion (1 microgram kg-1 min-1 i.v.

View Article and Find Full Text PDF

The hemodynamic and cardiac effects of the calcium antagonist nicardipine, alone (n = 10 patients) or combined with propranolol (0.1 mg/kg i.v.

View Article and Find Full Text PDF