Home About us Contact
|
Home About us Contact | ||
|
|
||
Drug Infusion (drug + infusion)
Selected AbstractsThe role of the ,-adrenergic receptor in the leg vasoconstrictor response to orthostatic stressACTA PHYSIOLOGICA, Issue 3 2009M. Kooijman Abstract Aim:, The prompt increase in peripheral vascular resistance, mediated by sympathetic ,-adrenergic stimulation, is believed to be the key event in blood pressure control during postural stress. However, despite the absence of central sympathetic control of the leg vasculature, postural leg vasoconstriction is preserved in spinal cord-injured individuals (SCI). This study aimed at assessing the contribution of both central and local sympathetically induced ,-adrenergic leg vasoconstriction to head-up tilt (HUT) by including healthy individuals and SCI, who lack central sympathetic baroreflex control over the leg vascular bed. Methods:, In 10 controls and nine SCI the femoral artery was cannulated for drug infusion. Upper leg blood flow (LBF) was measured bilaterally using venous occlusion strain gauge plethysmography before and during 30° HUT throughout intra-arterial infusion of saline or the non-selective ,-adrenergic receptor antagonist phentolamine respectively. Additionally, in six controls the leg vascular response to the cold pressor test was assessed during continued infusion of phentolamine, in order to confirm complete ,-adrenergic blockade by phentolamine. Results:, During infusion of phentolamine HUT still caused vasoconstriction in both groups: leg vascular resistance (mean arterial pressure/LBF) increased by 10 ± 2 AU (compared with 12 ± 2 AU during saline infusion), and 13 ± 3 AU (compared with 7 ± 3 AU during saline infusion) in controls and SCI respectively. Conclusion:, Effective ,-adrenergic blockade did not reduce HUT-induced vasoconstriction, regardless of intact baroreflex control of the leg vasculature. Apparently, redundant mechanisms compensate for the absence of sympathetic ,-adrenoceptor leg vasoconstriction in response to postural stress. [source] Antiepileptic Effect of Gap-junction Blockers in a Rat Model of Refractory Focal Cortical EpilepsyEPILEPSIA, Issue 7 2006Karen E. Nilsen Summary:,Purpose: Epilepsy is the most common serious neurologic disease, and current treatments are ineffective for ,30% of patients. Gap junctions have been implicated in seizure generation and propagation, and as such, may represent a novel therapeutic target but have been little investigated in vivo. We set out to assess the efficacy and tolerability of gap-junction blockers delivered to the seizure focus in a well-characterized model of refractory cortical epilepsy in rats. Methods: A chronic epilepsy focus was induced in the cortex of rats by using tetanus toxin, and subsequent studies were conducted in freely moving unanesthetized animals with frequent spontaneous seizures, as we previously described. Carbenoxolone, meclofenamic acid, and saline were applied directly to the seizure focus. EEG, electromyogram (EMG), and behavioral parameters were measured for ,1 h before drug infusion and for ,3 h afterward. No ill effects were observed. Results: An immediate and marked reduction in percentage of seizure time was seen in rats receiving carbenoxolone (baseline, 69.4%± 7.0% (SEM); maximum effect, 9.3%± 3.5%, p ,0.001) and meclofenamic acid (baseline, 58.3%± 3.7%; maximum effect, 0.92%± 0.92%, p < 0.001). No effect was seen after saline infusion. Conclusions: Gap-junction blockers applied focally are effective at suppressing seizures and, as such, represent a potential new treatment for epilepsy. Development of focal treatment strategies is essential in this regard. [source] Free fatty acids exert a greater effect on ocular and skin blood flow than triglycerides in healthy subjectsEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 8 2004M. Bayerle-Eder Abstract Background, Free fatty acids (FFAs) and triglycerides (TGs) can cause vascular dysfunction and arteriosclerosis. Acute elevation of plasma FFA and TG concentration strongly increase ocular and skin blood flow. This study was designed to discriminate whether FFA or TG independently induce hyperperfusion by measuring regional and systemic haemodynamics. Methods, In a balanced, randomized, placebo-controlled, double-blind, three-way, crossover study nine healthy subjects received either Intralipid® (Pharmacia and Upjohn, Vienna, Austria) with heparin, Intralipid® alone or placebo control. Pulsatile choroidal blood flow was measured with laser interferometry, retinal blood flow and retinal red blood cell velocity with laser Doppler velocimetry, and skin blood flow with laser Doppler flowmetry during an euglycaemic insulin clamp. Results, A sevenfold increase of FFA during Intralipid®/heparin infusion was paralleled by enhanced choriodal, retinal, and skin blood flow by 17 ± 4%, 26 ± 5% (P < 0·001), and 47 ± 19% (P = 0·03) from baseline, respectively. In contrast, a mere threefold increase of FFA by infusion of Intralipid® alone did not affect outcome parameters, despite the presence of plasma TG levels of 250,700 mg dL,1; similar to those obtained during combined Intralipid®/heparin infusion. Systemic haemodynamics were not affected by drug infusion. Conclusions, Present findings demonstrate a concentration-dependent increase in ocular and skin blood flow by FFA independently of elevated TG plasma concentrations. As vasodilation of resistance vessels occur rapidly, FFA may play a role in the development of continued regional hyperperfusion and deteriorate microvascular function. [source] Clinical Experience with a Novel Intracoronary Perfusion Catheter to Treat No-Reflow Phenomenon in Acute Coronary SyndromesJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 2 2010GABRIEL MALUENDA M.D. Background:,The no-reflow phenomenon is an often seen complication in patients presenting with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI). This event is associated with poor prognosis and poses a therapeutic challenge. Methods:,This retrospective study cohort was composed of 30 patients who presented with ACS between September 2007 and April 2009, and developed no-reflow during subsequent PCI. The primary end-point was defined as normal Thrombolysis In Myocardial Infarction (TIMI) 3 flow with myocardial blush grade (MBG) ,2 or an increase in TIMI flow by ,2 grades with a MBG ,2 after intracoronary drug infusion via the ClearWay (CW) RX perfusion catheter. Results:,The population presented with a relatively high prevalence of cardiovascular risk factors. ST-elevation myocardial infarction was the most common presentation (60.0%), while 20% of the patients presented with cardiogenic shock. After intracoronary infusion of nicardipine or nitroprusside using the CW catheter, TIMI flow improved from the baseline in 19 cases (63.3%, P < 0.001), and 16 patients (53.3%, P < 0.001) achieved normal coronary flow at the end of the procedure. The rate of in-hospital death was 6.7% (2 cases). No clinical differences were noted between those patients who successfully achieved normal coronary flow and those with persistent no-reflow. Conclusion:,The infusion of intracoronary drugs using the novel perfusion CW RX catheter seems to be safe and could help to improve myocardial perfusion in a selected group of patients presenting with ACS who developed no-reflow during PCI. (J Interven Cardiol 2010;23:109-113) [source] Bicuculline-induced brain activation in mice detected by functional magnetic resonance imagingMAGNETIC RESONANCE IN MEDICINE, Issue 2 2001Thomas Mueggler Abstract Dynamic measurements of local changes in relative cerebral blood volume (CBVrel) during a pharmacological stimulation paradigm were performed in mice. Using magnetite nanoparticles as an intravascular contrast agent, high-resolution CBVrel maps were obtained. Intravenous administration of the GABAA antagonist bicuculline prompted increases in local CBVrel as assessed by MRI with a high spatial resolution of 0.2 × 0.2 mm2 and a temporal resolution of 21 s. Signal changes occurred 20,30 s after the onset of drug infusion in the somatosensory and motor cortex, followed by other cortical and subcortical structures. The magnitudes of the CBVrel increases were 18% ± 4%, 46% ± 14%, and 67% ± 7%, as compared to prestimulation values for the cortex, and 9% ± 3%, 25% ± 4%, and 36% ± 7% for the caudate putamen for bicuculline doses of 0.6, 1.25, and 1.5 mg/kg, respectively. On-line monitoring of transcutaneous carbon dioxide tension PtcCO2 reflecting arterial PaCO2 did not show any alteration during the stimulation paradigm. One of five of the mice receiving the highest bicuculline dose, and three of seven receiving the intermediate dose displayed a different cortical response pattern. After a CBVrel increase of 40% lasting for approximately 1 min, significant CBVrelreductions by 80% have been observed. Subcortical structures did not display this behavior. The present study suggests that this noninvasive approach of functional MRI (fMRI) can be applied to study drug-induced brain activation by central nervous system (CNS) drugs in mice under normal and pathological situations. Magn Reson Med 46:292,298, 2001. © 2001 Wiley-Liss, Inc. [source] Patient-controlled Analgesia in Intrathecal Therapy for Chronic Pain: Safety and Effective Operation of the Model 8831 Personal Therapy Manager with a Pre-implanted SynchroMed Infusion SystemNEUROMODULATION, Issue 3 2003Jan Maeyaert Abstract The Model 8831 Personal Therapy Manager (PTM) offers a patient-controlled analgesia (PCA) option for the SynchroMed Infusion System (Medtronic Inc., Minneapolis, MN). The safety and effective operation of the PTM activator was evaluated in 45 patients in five European centers receiving intrathecal drug infusion for the treatment of chronic pain via a SynchroMed pump. The total volume of drug delivered intrathecally over a four-week follow-up period was calculated. Adverse events were recorded and pain levels were measured via the Visual Analog pain Scale (VAS), Brief Pain Inventory, and SF-12 Quality of Life scores. Patient satisfaction with the device and its instruction manual was also assessed by questionnaire. The expected and calculated intrathecal drug volumes (and therefore drug doses) were the same, demonstrating that the device worked as intended. There were no device-related serious adverse events. Overall, 96% of patients were satisfied with the activator. Patients appreciated being able to control their pain and considered the device and its instructions easy to use. The PTM was shown to be safe and functioning properly in the intrathecal treatment of pain. The successful addition of a PCA function to the SynchroMed system may create a new standard in intrathecal pain therapy. [source] Management of patients with non,ST-segment elevation acute coronary syndromes: Insights from the pursuit trialCLINICAL CARDIOLOGY, Issue S5 2000Dan J. Fintel M.D The glycoprotein (GP) IIb-IIIa inhibitor eptifibatide (INTEGRILIN®, COR Therapeutics, Inc., South San Francisco, California, and Key Pharmaceuticals, Inc., Kenilworth, New Jersey) is a novel and highly potent antithrombotic agent indicated for the management of patients with non-ST-segment elevation acute coronary syndromes (ACS) and those undergoing percutaneous coronary intervention. The approval of eptifibatide for non-ST-segment elevation ACS was based on the positive results of the Platelet Glycoprotein IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy (PURSUIT) trial. With enrollment of almost 11,000 patients, not only is the PURSUIT trial the largest trial of a GP IIb-IIIa inhibitor to date, but it is also the largest clinical study ever conducted in patients with non-ST-segment elevation ACS. The key feature of the PURSUIT trial is that patient management closely resembled standard clinical practice, because decisions about the use and timing of invasive cardiac procedures were made by the individual physicians rather than being prespecified in the study protocol. Eptifibatide therapy was associated with a significant reduction in the incidence of the primary endpoint,a composite of death or myocardial infarction at 30 days (14.2 vs. 15.7% in the placebo group; p = 0.042). Of importance is the fact that the beneficial effect of eptifibatide was independent of the management strategy pursued during study drug infusion (invasive or conservative), and it was achieved with few major safety concerns. These findings demonstrate that the use of eptifibatide should be considered for all patients presenting with signs and symptoms of intermediate- to high-risk non-ST-segment elevation ACS. [source] Infliximab in the surgical management of complex fistulating anal Crohn's diseaseCOLORECTAL DISEASE, Issue 2 2005C. Talbot Abstract Objectives To assess prospectively the efficacy and safety of treatment of perianal Crohn's disease by means of a combination of surgical management and a standardized protocol for the intravenous infusion of infliximab. Methods A consecutive series of patients who presented with complex perianal Crohn's fistulae between November 1999 and March 2003 were included in the study. Perianal sepsis was eradicated with drainage of collections and insertion of setons. Infliximab was infused at 5 mg/kg at 0, 2, and 6 weeks. Setons were removed after the second infliximab infusion. Endpoints were defined as either complete, partial or no response as noted at subsequent outpatient follow up. Adverse reactions were recorded. Results Twenty-one patients had a median of three fistulae per patient (range 1,9). All patients tolerated the initial protocol, receiving a median of five infusions of infliximab (range 3,19); median follow up 20 months (range 12,52). Eleven patients (53%) were continued on maintenance therapy with 12 weekly infusions of infliximab for either a perceived clinical need for treatment or after a relapse of their symptoms. Ten (47%) patients experienced a complete response to treatment and the remaining 11 (53%) experienced a partial response. No patient failed to respond to treatment. Four adverse reactions were noted (2 mild allergies, 1 rash and 1 patient experienced joint pains). All adverse reactions settled with cessation of the drug infusion. Conclusions The combination of seton drainage and infusion of infliximab completely healed the perineum of 47% patients with complex fistulating perianal Crohn's disease. Partial response was seen in the remainder of patients. No serious adverse reactions reported. [source] Validation of a New Noninvasive Device for the Monitoring of Peak Endocardial Acceleration in Pigs: Implications for Optimization of Pacing Site and ConfigurationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 7 2008PIERRE BORDACHAR M.D. Introduction: The peak of endocardial acceleration (PEA) is an index of myocardial contractility. We aimed to (1) demonstrate that the PEA measured by the noninvasive cutaneous precordial application of an accelerometer sensor is related to left ventricular (LV) dP/dt max and (2) assess the usefulness of PEA monitoring during graded ischemia and during different configurations of sequential biventricular pacing. Methods and Results: Measurements of invasive LV dP/dt max were compared with measurements of transcutaneous PEA in seven pigs at baseline and during acute drug infusions; increased heart rate; right, left, biventricular and sequential biventricular pacing before and after graded ischemia induced by the constriction of the left anterior descending coronary artery. A consistent PEA signal was obtained in all animals. PEA changes were highly related to LV dP/dt max changes (r= 0.93; P < 0.001). The changes of LV contractility induced by the different pacing configurations were detected by PEA analysis in the absence of ischemia (r= 0.94; P < 0.001) and in the presence of ischemic LV dysfunction (r= 0.91; P < 0.001). Conclusion: Noninvasive PEA measurement allows monitoring of left ventricular contractility and may be a useful tool to detect global effect of ventricular ischemia and to optimize the choice of both pacing site and pacing configuration. [source] The pattern of intravenous drug administration during the transfer of critically ill children by a specialist transport teamPEDIATRIC ANESTHESIA, Issue 10 2006AGNI S. SAHA MD Summary Background:, There are few published data on the patterns of intravenous drug administration by specialist pediatric intensive care unit (PICU) transport teams during the transfer of critically ill children between hospitals. Methods:, A retrospective review of retrieval documentation was undertaken for all patients transported by the Royal Manchester Children's Hospital PICU transport team over a period of 1 year. Results:, A total of 257 patients were transported during the study period, 82 patients (32%) were excluded owing to incomplete or absent documentation, leaving a sample of 175 available for analysis. Intravenous drugs were administered to 168 of these patients (96%). In total, 38 different drugs were administered. The four most commonly administered drugs were midazolam (130 patients), morphine (129 patients), atracurium (108 patients), and heparin (53 patients). Ten drugs accounted for 90% of all prescription episodes (total number of infusions and bolus doses administered), whilst 16 drugs were prescribed only once. The mean number of drugs administered per patient was 3.25 with a mean of 1.96 drug infusions and 1.29 bolus drugs administered per patient. Conclusions:, A relatively small number of drugs are used frequently during the retrieval of critically ill children, but the total range of drugs that are used is large. This has implications for the rational carriage of drugs by PICU transport teams, the potential for drug errors and also for the development of advanced nurse practitioners whose prescribing-like activities may depend on the development of Patient Group Directions. [source] The effect of esmolol on the QTc interval during induction of anaesthesia in patients with coronary artery diseaseANAESTHESIA, Issue 3 2009F. Erdil Summary The aim of this study was to evaluate whether esmolol has an effect on QT interval during induction of anaesthesia using etomidate and fentanyl in patients with known coronary artery disease. Sixty patients were prospectively randomised to either a control group or the esmolol group. Esmolol was administered as a bolus 1 mg.kg,1, followed by a continuous infusion at 250 ,g.kg,1min,1. All patients received etomidate 0.3 mg.kg,1 and fentanyl 15 ,g.kg,1. The ECG was recorded prior to induction of anaesthesia (T0), 5 min following the start of drug infusions (T1), 1 min following etomidate (T2), 3 min following vecuronium (T3), 30 s (T4), 2 min (T5) and 4 min (T6) after intubation. In the esmolol group, QTc interval was significantly shorter at T1, T2 and T4 compared to the control group (p < 0.05). In conclusion, QTc interval increased following tracheal intubation during induction of anaesthesia using etomidate and fentanyl. An infusion of Esmolol attenuated the QTc interval prolongation associated with tracheal intubation. [source] | ||||||||||||||||||||||