Search results for "HEMODYNAMICS"
showing 10 items of 511 documents
Effect of ischaemic preconditioning, cardiopulmonary bypass and myocardial ischaemic/reperfusion on free radical generation in CABG patients.
2001
Abstract Objective: To investigate the free radicals (FR) generation after ischaemic preconditioning and cardiopulmonary bypass and during reperfusion in CABG patients, and the role of ischaemic preconditioning. Methods: Forty-three CABG patients were randomised into an ischaemic preconditioning and a control group. The protocol for ischaemic preconditioning was two cycles of 2-min ischaemia followed by 3-min reperfusion. Free radicals were measured using electron spin resonance spectroscopy. Global and right heart functions were collected. Results: The free radicals generation in coronary sinus blood in the ischaemic preconditioning group was 9.7 and 16.6% after the ischaemic preconditioni…
Transthoracic and transesophageal echocardiography to diagnose ventricular septal rupture
1993
BACKGROUND Rapid and accurate diagnosis of ventricular septal rupture (VSR) remains difficult, and the monitoring of hemodynamic deterioration is a prerequisite for the institution of adequate therapy. The timing of surgical repair is a matter of controversy. METHODS Transthoracic, transesophageal, color Doppler, and contrast echocardiography were evaluated in 17 patients with VSR in whom the diagnosis was confirmed by catheterization, surgery, or necropsy. RESULTS Routine transthoracic echocardiography visualized VSR in four out of 17 patients and, with additional views, in 12 out of 17 patients. Color Doppler echocardiography identified the rupture in 15 out of 16, and contrast echocardio…
Inflammatory pathways in patients with heart failure and preserved ejection fraction.
2008
Immune activation is well established in patients with chronic heart failure and reduced ejection fraction (HF and reduced EF) and is associated with an impaired prognosis. Patients with heart failure and preserved ejection fraction (HF and preserved EF) have an impaired prognosis as well. It is not known whether they have signs of immune activation.We studied patients with HF and preserved EF (n=17, NYHA II [n=7]/III [n=10]) and patients with HF and reduced EF (n=17 NYHA II [n=1]/III [n=16]) and 20 controls. Echocardiography demonstrated preserved ejection fraction (LVEF 59+/-9%), but LV hypertrophy in patients with preserved EF as compared with patients with reduced EF (LVEF 23+/-5%). We …
Single shot spinal anaesthesia with hypobaric bupivacaine for hip fracture repair surgery in the elderly. Randomized, double blinded comparison of 3.…
2014
Arterial hypotension is the most frequent adverse effect of subarachnoid anaesthesia in the elderly sustaining a femoral proximal fracture. Decreasing the local anaesthetic dose reduces the incidence of hypotension but shortens sensory block duration that could be insufficient in some surgical procedures. Sensory block duration could be prolonged using hypobaric local anaesthetics. We evaluated whether low hypobaric bupivacaine doses were adequate for this type of surgery while maintaining the haemodynamic stability.A prospective, randomized, double blinded study was designed. Patients over 65 years old, sustaining traumatic hip fracture, were assigned to one of two groups: B0.5 group, hypo…
Single shot spinal anesthesia with very low hyperbaric bupivacaine dose (3.75mg) for hip fracture repair surgery in the elderly. A randomized, double…
2014
Single shot spinal anesthesia is used worldwide for hip fracture repair surgery in the elderly. Arterial hypotension is a frequent adverse effect. We hypothesized that lowering local anesthetics dose could decrease the incidence of arterial hypotension, while maintaining quality of surgical anesthesia.In a randomized double blinded study, 66 patients over the age of 65 years, with hip fracture needing surgical repair, were assigned to B0.5 group 7.5mg hyperbaric bupivacaine 5mg/ml (control group), and B0.25 group 3.75mg hyperbaric bupivacaine 2.5mg/ml (study group). Sensory and motor block level, and hemodynamic parameters including blood presure, heart rate and vasopressor dose administrat…
Role of Rate Control and Regularization Through Pacing in Patients With Chronic Atrial Fibrillation and Preserved Ventricular Function: The VRR Study
2006
Aim: High heart rates in chronic atrial fibrillation (CAF) is one of the factors responsible for hemodynamic alterations and may lead to tachycardiomyopathies. The ventricular rate regulation (VRR) study evaluates the effect of ventricular rate regularization in CAF patients with preserved ventricular function, marked ventricular rate variability, and indications for pacemaker (PM) implantation owing to symptomatic pauses. Rate regularization was achieved using VRR algorithm (INSIGNIA® pacemakers, Guidant Corp., St. Paul, MN, USA). Methods: One month after PM implantation, 58 patients followed two 3-month crossover periods (VRR-OFF; VRR-ON) in which the VRR algorithm was randomized and comp…
Significance of resting and stimulated cerebral blood flow for predicting the risk of hemodynamic cerebral ischemia in a model of chronic hemodynamic…
2000
OBJECTIVE: It has been postulated that patients with a compromised cerebrovascular reserve capacity (RC), defined as cerebral blood flow (CBF) response to acetazolamide (ACZ) (by percent), are at higher risk for ischemic stroke. The value of CBF and RC for predicting the risk of hemodynamically induced impairment of cerebral function is examined. METHODS: Both common carotid arteries were occluded in 22 Wistar-Kyoto rats. Thirty-one days later, mean arterial blood pressure was reduced to 40 mm Hg for 30 minutes. Laser Doppler scanning of CBF at resting conditions and after intraperitoneal administration of ACZ (0.1 mg/g body weight) was performed 30 minutes and 28 days after occlusion as we…
On the number of measurement sites required to assess regional cerebral blood flow by laser-Doppler scanning during cerebral ischemia and reperfusion.
2001
The aim of this study was to determine whether the number of measurement sites affected the precision of regional cerebral blood flow (CBF) assessment by Laser-Doppler (LD). A simulation study was applied based on data obtained by scanning the cortex in 25 rats during baseline conditions, 15 min global cerebral ischemia and reperfusion. Random samples were repeatedly collected from 1 to 100 locations and deviations from the median of the entire CBF data pool (800 locations) were determined. Single location CBF measurements missed the true median by 24.8+/-2.2 LD-units (baseline conditions, n=100 simulations, mean+/-SEM), 2.7+/-0.6 LD-units (ischemia), and 31.9+/-2.4 LD-units (30th min reper…
PLASMA PROTEIN LOSS DURING SURGERY: BENEFICIAL EFFECTS OF ALBUMIN SUBSTITUTION
2001
Plasma protein loss during abdominal surgery is a known phenomenon, but its possible pathophysiological relevance has remained unknown. The present study evaluates the effects of albumin substitution on systemic and local hemodynamics and cellular interactions in the mesenteric microcirculation. Rats underwent median laparotomy and exteriorization of an ileal loop for intravital microscopy of the mesenteric microcirculation. Plasma protein concentrations, systemic and local hemodynamics were recorded during the follow up period, with or without albumin substitution. Depending on the time course of plasma protein loss in control experiments, 80% of the calculated protein loss was infused dur…
NEONATAL CAPSAICIN TREATMENT DOES NOT PREVENT SPLANCHNIC VASODILATATION IN PORTAL-HYPERTENSIVE RATS
1994
It has been suggested that the peripheral sensory neurons are involved in the splanchnic hemodynamic changes of portal hypertension. Therefore the influence of permanent ablation of sensory neurons by neonatal capsaicin pretreatment (50 mg/kg, subcutaneously) on the development of the hyperdynamic splanchnic circulation in portal-hypertensive rats was studied. In adulthood, portal hypertension was induced with partial portal vein ligation. In study 1, systemic and splanchnic hemodynamics were measured by means of a radiolabeled-microsphere technique in portal-hypertensive rats, under ketamine anesthesia, pretreated with capsaicin or vehicle. Mean arterial pressure, heart rate, cardiac index…