Arterial Pressure Decreased (arterial + pressure_decreased)

Distribution by Scientific Domains


Selected Abstracts


Modulation of systemic and renal haemodynamics by ,-opioids in conscious lambs

EXPERIMENTAL PHYSIOLOGY, Issue 5 2006
Wei Qi
The purpose of the present study was to determine the cardiovascular effects of the ,-opioid receptor agonist U-50488H at two stages of postnatal maturation under physiological conditions. Experiments were carried out firstly to define systemic and renal haemodynamic responses to ,-opioid receptor activation and, secondly, to determine whether these effects are altered during postnatal maturation. To investigate whether the responses to U-50488H resulted from receptor-dependent effects, responses to U-50488H were also tested in the presence of the specific ,-opioid receptor antagonist 5,-guanidinonaltrindole (GNTI). Experiments were carried out in two groups of conscious, chronically instrumented lambs aged ,1 and ,6 weeks. Mean arterial pressure, mean venous pressure and renal blood flow (RBF) were measured for 30 min before and 90 min after i.v. injection of U-50488H or vehicle. Heart rate increased in both age groups of lambs within 10 min of U-50488H administration. Mean arterial pressure decreased for 50 min following U-50488H administration at 1 week but, in contrast, increased transiently at 10 min in 6-week-old lambs, returning to control levels by 20 min. In both age groups, there was a sustained decrease in RBF following U-50488H. The aforementioned responses to U-50488H were abolished by pretreatment with GNTI. These data provide the first measurements of systemic and renal haemodynamic responses to ,-opioid receptor activation during postnatal maturation. [source]


Nocturnal Hemodialysis Is Better Than Quotidian Hemodialysis

HEMODIALYSIS INTERNATIONAL, Issue 1 2003
MP Kooistra
Background. It is unknown whether long nocturnal (6,7 times weekly 6,8 hours) hemodialysis (NHD) is better than frequent short hemodialysis (,daily', quotidian hemodialysis, QHD). Methods. A Dutch NHD pilot study (,Nocturne') started in December 2001. We can now evaluate effects of 4 months NHD in 14 patients. Baseline dialysis frequency was 3.5 or less (3.13 ± 0.23, M ± SD) in group A (n = 8), and 4 or more (5.0 ± 0.89) in group B (n = 6), weekly dialysis time was equal in both groups. Results. Single pool Kt/V, being higher in group B at baseline, increased in both groups (A: 3.1 ± 0.8/week to 9.5 ± 2.3, B: 3.8 ± 1.0 to 10.9 ± 4.1). Baseline nPCR, being higher in group B, increased in both groups (A: 1.0 ± 0.3 g/kg/week to 1.4 ± 0.3, and B: 1.2 ± 0.5 to 1.8 ± 0.5). Baseline albumin was higher in group B, and increased in group A (39.6 ± 3.7 g/l to 43.2 ± 1.5), not in B (41.4 ± 2.3 to 42.8 ± 2.3). Target weight increased only in group A (71.8 ± 10.5 kg to 75.3 ± 11.9), not in B (71.4 ± 25.5 to 71.3 ± 26.7). NHD resulted in normophosphatemia in both groups despite phosphate supplementation and cessation of phosphate binders. PTH decreased in both groups (A: 40.6 ± 38.0 pmol/l to 14.4 ± 11.7, B: 35.6 ± 37.7 to 22.4 ± 41.5). In both groups, pre- and postdialysis mean arterial pressure decreased (A: 106.8 ± 7.9 mmHg to 94.4 ± 12.1 and 97.3 ± 9.5 mmHg to 86.3 ± 8.2, B: 102.2 ± 28.4 to 89.4 ± 9.5 and 90.3 ± 26.8 to 82.7 ± 12.9). Antihypertensives were discontinued or markedly reduced. Fatigue, insomnia, prurigo, restlessness, appetite, physical condition, working ability and quality of life (SF36) improved significantly in both groups. Conclusion. This small pilot study suggests that phosphate and PTH control, blood pressure, uremic symptoms and quality of life improve when conventional hemodialysis or QHD patients switch to NHD. Nutritional parameters improve only in the previously conventionally treated group. [source]


Different bispectral index values from both sides of the forehead in unilateral carotid artery stenosis

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2009
E. H. LEE
Bispectral index (BIS) values derived from the left and right forehead are usually the same. We report on two patients with unilateral carotid artery stenosis in whom we observed differences between the BIS values obtained from sensors placed on each side of the forehead. During surgery, the BIS values of the diseased side decreased more than those of the opposite side when the mean arterial pressure decreased below 70 mmHg. BIS monitors should be used with caution in patients with unilateral carotid artery and cerebrovascular disease. [source]


PERCUTANEOUS TRANSCATHETER CLOSURE OF PATENT DUCTUS ARTERIOSUS WITH AN AMPLATZER DUCT OCCLUDER USING RETROGRADE GUIDEWIRE-ESTABLISHED FEMORAL ARTERIOVENOUS LOOP

CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 5-6 2008
Jian-Fa Zhang
SUMMARY 1The traditional antegrade wire-guided percutaneous transcatheter approach is not ideal in closing some types of patent ductus arteriosus (PDA) with abnormal morphology. The aim of the present study was to evaluate the efficacy of a retrograde wire-guided transcatheter approach for closure of some types of PDA using the Amplatzer duct occluder (ADO). 2Nineteen patients with abnormal PDA morphology, including a smaller ostium of the side of the pulmonary artery compared with the side of the descending aorta, severe calcification or tortuosity, were included in the present study. In these patients, after the antegrade approach failed to cross a wire from the pulmonary artery via the PDA to the descending aorta, a retrograde guidewire was passed through the PDA in the opposite direction, from the descending aorta to the pulmonary artery, to establish a femoral arteriovenous loop that assisted the deployment of the ADO in all 19 patients. The size of the PDA, as determined by angiography, was 3.1 ± 1.1 mm and the diameter of the ADO selected was 6.5 ± 1.5 mm. 3In 16 cases, systolic murmur disappeared after the procedure. Systolic murmur (less than Grade II) and angiographic residual shunt remained in three cases immediately after the procedure, but disappeared 1 month later. Mean pulmonary arterial pressure decreased from 33 ± 8 to 22 ± 4 mmHg in all 19 patients (P < 0.01). There were no complications during or after the procedure. 4The retrograde wire-guided technique offers an alternative approach to facilitate closure of a PDA that cannot be achieved by traditional antegrade wire-guided methods due to morphological abnormalities in the PDA. [source]


The electrocardiographic and hemodynamic effect of metohexital and propofol with and without esmolol

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2006
R. Korpinen
Background:, Metohexital and propofol are short-acting induction agents, which have a tendency to prolong the QTc interval of the ECG. We studied whether this increase could be prevented by combining a beta-blocking agent, esmolol, with these drugs. Simultaneously, we studied the hemodynamic effects of these combinations. Methods:, In a randomized, double-blind study, 80 ASA I,II young adults were premedicated with oxycodone and atropin and allocated to one of four groups: propofol (P), propofol + esmolol (P + E), metohexital (E) or metohexital + esmolol (M + E). The doses were 2 mg/kg propofol/metohexital and 1 mg/kg esmolol. Alfentanil 15 µg/kg was used in all groups. The hemodynamic parameters were measured non-invasively and the electrocardiographic parameters using the signal processing method. Result:, The highest QTc values, which often exceeded the normal upper limit of 440 ms, were recorded at the baseline or immediately after the administration of the induction drugs. The intervals were significantly shorter if esmolol was co-administered with either propofol or metohexital. The heart rate increased in the group M and decreased in the group P + E but remained unchanged in the groups P and M + E. Systolic and diastolic arterial pressures decreased during the study in all groups, most prominently in group P + E. Conclusions:, During the anesthesia induction, the QTc interval was significantly shorter when esmolol was co-administered with either propofol or metohexital. The hemodynamic responses were properly controlled with the combination of metohexital and esmolol as well as with propofol alone, but the combination of propofol and esmolol tended to cause hemodynamic depression. [source]


Continuous Vagus Nerve Stimulation Effects on the Gut-Brain Axis in Swine

NEUROMODULATION, Issue 1 2007
Idoia Díaz-Güemes DVM
ABSTRACT Objectives., This study was designed to assess vagus nerve stimulation effects on the food intake pattern in swine and determine the electrical stimulus direction. Material and Methods., Fifteen Large White pigs were randomly divided into three groups, groups A,C. All animals underwent implantation of a vagus nerve stimulator at the gastro-esophogeal junction. In group A, the stimulation was switched off, whereas stimulation was switched on in groups B and C. Food intake and body weight were registered in groups A and B, but not in group C, which was used to measure direction of stimulation in the vagus and effect on heart rate and blood pressure. Variables measured in group C included the bispectral index, blood pressure, and heart rate. A Student's t -test and one-way analysis of variance were used to detect differences between groups. All animals were sacrificed to identify effects of implantation and stimulation on the vagus nerve. Results., With respect to food intake, there was no difference between groups A and B; however, body weight did register a continuous increase. During stimulation, in group C arterial pressures decreased significantly, whereas the heart rate and bispectral index increased. Conclusion., The stimulation protocol applied in this study was insufficient to cause changes in the feeding behavior of swine; however, it did increase central nervous system activity. [source]