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101.
Dyssynchronous ventricular contraction in severe heart failurecontributes to low cardiac output, worsening symptoms, and poorprognosis. Recognition of the effect of dyssynchrony in heartfailure, and the possibility of manipulating the sequence ofelectrical cardiac activation to improve the efficiency of mechanicalevents, led Cazeau et al. to attempt four-chamber pacing in1994.1 This early system could stimulate both atria and bothventricles extrinsically, and could dictate the temporal relationshipbetween atrial systole and ventricular systole, and the ventriculo-ventricularrelationship. Modern cardiac resynchronization therapy (CRT),involving pacing of the right and left ventricles, with rightatrial pacing to optimize atrio-ventricular delay, has evolvedrapidly from this beginning. Left bundle branch block (LBBB) on the surface electrocardiogram(ECG) has been considered a marker of mechanical dyssynchronyas it represents a delay in conduction of depolarization tothe left ventricle, with the greatest delay usually being in  相似文献   
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Background  

Previous studies regarding the use of information technologies (IT) specifically among pediatricians and other physicians who treat children are lacking. As such, the objective of this study is to examine the use of electronic health record (EHR) systems and other IT applications among pediatricians and other child health providers (CHPs) in Florida.  相似文献   
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Background: Loss of consciousness (LOC) and immobility to surgical incision seem to be mediated at different levels of the central nervous system. Pharmacologic studies of hypnotic agents have previously focused on combinations of either volatile or intravenous anesthetics. This study examined the combination of inhaled sevoflurane and intravenous propofol at these two clinically relevant anesthetic end points.

Methods: Thirty-six elective surgical patients were initially enrolled. Conditions approximating steady state were obtained for sevoflurane and target-controlled propofol infusions. Patients were sequentially evaluated for LOC (loud voice plus mild prodding) and immobility to surgical incision. The study was designed using the Dixon up-down method.

Results: The observed propofol effect target with 50% response plus sevoflurane (0.46% end-tidal concentration) was 1.2 [mu]g/ml (95% confidence interval, 1.1-1.3 [mu]g/ml). It was not significantly different from that predicted (1.5 [mu]g/ml; 95% confidence interval, 1.2-1.7 [mu]g/ml) by simple additivity. The effective plasma concentration of propofol that suppressed movement to skin incision in 50% of patients was 5.4 [mu]g/ml (95% confidence interval, 4.8-6.0 [mu]g/ml) plus sevoflurane (0.86%) and was not significantly different from that predicted by additivity (5.4 [mu]g/ml; 95% confidence interval, 4.8-5.9 [mu]g/ml). Both analyses had adequate power (90%) to detect a significant change (+/-19 to 25%) from predicted value. Repeated-measures analysis of variance identified a Bispectral Index value of 70 as the break point between those who responded at LOC or did not.  相似文献   

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Background: This study evaluated the ability of dexmedetomidine to provide analgesia and sedation for outpatient colonoscopy, examining outcomes including cardiorespiratory variables, side effects, and discharge readiness.

Methods: Sixty-four patients were randomly assigned to one of three treatment regimens. In group D, patients received 1 [mu]g/kg dexmedetomidine over 15 min followed by an infusion of 0.2 [mu]g [middle dot] kg-1 [middle dot] h-1. Group P received meperidine (1 mg/kg) with midazolam (0.05 mg/kg), and group F received fentanyl (0.1-0.2 mg intravenous) on demand. The assessment included measurements of heart rate, blood pressure, oxygen saturation, respiratory rate, quality of sedation/analgesia, and an evaluation of the recovery time.

Results: The study was terminated before the planned 90 patients had been recruited because of adverse events in group D. In all groups, negligible hemoglobin oxygen saturation and respiratory rate variations were observed. In group D, there was a significantly larger decrease in heart rate (to approximately 40 beats/min in 2 of 19 cases) and blood pressure (to less than 50% of the initial value in 4 of 19 patients). Supplemental fentanyl was required in 47% of patients receiving dexmedetomidine to achieve a satisfactory level of analgesia (vs. 42.8% of patients in group P and 79.2% of patients in group F). Vertigo (5 patients), nausea/vomiting (5 patients), and ventricular bigeminy (1 patient) were observed only in group D. Time to home readiness was longest in group D (85 +/- 74, 39 +/- 21, and 32 +/- 13 min in groups D, P and F, respectively; P = 0.007).  相似文献   

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OBJECTIVE: To determine the effectiveness of a 10-day subcutaneous erythropoietin (rHuEpo) course of 300 units per kg per dose plus oral iron compared to oral iron alone in anemic infants during their convalescent phase of illness. STUDY DESIGN: Prospective, randomized trial performed at a 40-bed, teaching, referral, level III, neonatal intensive care unit. Infants with a gestational age at birth of less than 32 weeks, hematocrit of less than or equal to 28% with a corrected reticulocyte count of less than or equal to 5%, postconceptual age of less than 48 weeks or 5 months chronological age, and a diagnosis of anemia of prematurity were considered for inclusion. Major outcome parameters included hematocrit, corrected reticulocyte count and red cell transfusion requirements. RESULTS: A total of 60 infants were enrolled (n=30 per group). Infants randomized to rHuEpo had a significantly higher post-treatment hematocrit and corrected reticulocyte count than infants in the iron only group (p<0.001). There was a trend towards fewer red cell requirements in the rHuEpo group. CONCLUSIONS: The rHuEpo regimen studied here was associated with an acute improvement in hematocrit and corrected reticulocyte counts. This study did not demonstrate a statistically significant decrease in transfusion therapy, in part related to increased subsequent use of rHuEpo in the control group. Taken together, these data demonstrate that this regimen can effectively treat anemia in convalescent premature infants.  相似文献   
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