bluuebunny/crossref_metadata_2025_split huggingface dataset:
Applying Marketing Concepts to Promote Health in Vulnerable Groups
Authors: Fontana Susan A. 
Published: May 2007

AbstractPublic health nurses must have a valid marketing orientation. Two marketing concepts, exchange relationships and channels of distribution and their application for public health nursing practice, have relevance in this context. In spite of the complexities inherent in applying them, they can be used to promote health in at‐risk populations. By incorporating these concepts in planning and delivering public health nursing services, it is hoped that the health goals of a larger number of vulnerable individuals can be achieved.
Determinants of Home Care Nursing Hours for Technology‐Assisted Children
Authors: Leonard Barbara J. , Brust Janny Dwyer , Sielaff Bruce H. 
Published: May 2007

AbstractIn the 1980s home care, in contrast to hospital care, was reported substantially to reduce costs for third‐party payers who provided funding for technology‐assisted children. Savings were realized primarily because parents substituted for nurses, eliminating or reducing those costs. Third‐party payers' savings thus were directly related to the number of hours parents assumed care. Because home care relies on parents doing some of the work of nurses, decisions regarding nursing hours must consider family factors in addition to medical factors. We evaluated the number of nursing hours 31 Minnesota families with technology‐assisted children received, as well as the factors that determined the allotment of nursing hours. Most families (96.8%) received some hours of professional nursing care per day, and 16.1% received 24‐hour care. Multiple regression, however, showed that family factors, rather than the child's medical condition, influenced the number of hours, with married, lower‐income families with a younger child receiving the fewest.Further discussion and study are recommended to understand more fully the impact family factors have on the allotment of nursing hours and home care costs.
Analysis of a Home Health Agency's Productivity System
Authors: Hellman Esther A. 
Published: May 2007

AbstractProductivity is an important issue in home care. Employee perceptions of an equitable system are crucial and have been linked to job satisfaction, motivation, and production. Ten staff nurses, and all supervisors and program directors were interviewed to elicit perceptions of the productivity system. Staff nurses' time sheets for seven months were evaluated retrospectively for visit length, number of visits per day, payer source, mileage per day, and travel time per day. Mean time in minutes spent in the patient's home on intravenous visits (n = 58 visits) was approximately twice as long as that of home care visit (n= 11,573 visits). Mean length of hospice visits (n= 368 visits) was 25 to 29 minutes longer than that of mean home care visits. The proportion of Medicare reimbursement was negatively correlated with productivity bonus point achievement (when two high and two low bonus point outliers were removed). Recommended changes were based on both qualitative analysis of employee perceptions of the productivity system and quantitative analysis of time sheets.
Vagus Nerve Stimulation Therapy Induces Changes in Heart Rate of Children during Sleep
Authors: Zaaimi Boubker , Grebe Reinhard , Berquin Patrick , Wallois Fabrice 
Published: May 2007

Summary:  Purpose: This study analyzed changes in the heart rates of children receiving vagus nerve stimulation (VNS) therapy for pharmacoresistant epilepsy. Methods: Changes in the heart rates of ten children receiving VNS therapy for pharmacoresistant epilepsy were evaluated with polysomnographic recordings, including electrocardiogram (ECG), EEG, thoraco‐abdominal distension, nasal airflow, and VNS artifacts. Measurements during stimulation were compared with those at baseline for each patient. Result: While the VNS therapy pulse generator was delivering stimulation, the heart rates of four children increased significantly (p < 0.01), decreased for one child, and increased at the end of the stimulation for one child. The heart rates of four children did not change. Changes in heart rate varied during VNS, within stimulation cycles for individual children and from one child to another. Changes in heart rate differed between rapid eye movement (REM) and non‐REM (NREM) sleep states. Respiratory changes (increases in frequency and decreases in amplitude) were concomitant with the changes in heart rate. Conclusion: In this case series of children with pharmacoresistant epilepsy, cardiorespiratory variations occurred while the VNS therapy pulse generator was delivering stimulation. Understanding these variations may allow further optimization of VNS parameters.
Epilepsy and Toxocariasis: A Case‐Control Study in Burundi
Authors: Nicoletti Alessandra , Bartoloni Alessandro , Sofia Vito , Mantella Antonia , Nsengiyumva Georges , Frescaline Guilhem , Preux Pierre‐Marie 
Published: May 2007

Summary:  Purpose: A case‐control study to assess the relationship between epilepsy and toxocariasis was carried out in the Kiremba population, Burundi. Methods: People with epilepsy (PWE) were diagnosed according to the definition proposed by the International League Against Epilepsy (ILAE). Seizures were classified according to the classification proposed by ILAE in 1981. One control per case was selected matched by age (±5 years). Control subjects also lived in Kiremba, had neither neurological disorders nor kinship with the PWE. Cases and controls were assessed serologically for antibodies against Toxocara canis by an immunoblotting assay. Odds ratios (ORs) and 95% CI were determined using conditional regression analysis for matched case‐control study. Results: One hundred ninety‐one PWE (99 men and 92 women) and 191 age‐matched controls (72 men and 112 women) were enrolled in the study. Of the 191 PWE, 113 presented partial seizures while 73 generalized seizures and five were unclassifiable. Antibodies anti T. canis were found in 114 PWE (59.7%) and in 97 controls (50.8%). Multivariate analysis (conditional logistic regression) showed a significant association between positivity for T canis and epilepsy with an adjusted OR of 2.13 (95% CI 1.18–3.83; p‐value 0.01). Conclusions: We found a significant association between toxocariasis and epilepsy. In agreement with a previous study, our finding suggests that toxocariasis may increase the risk of developing epilepsy in endemic areas and could participate to the high burden of epilepsy in tropical areas.
Orthostatic Versus Electrophysiologic Testing in Unexplained Syncope in Children and Adolescents
Authors: ROSS BERTRAND A. , HUGHES SUSANNE , ANDERSON ELAINE , GILLETTE PAUL C. 
Published: May 2007

Orthostatic vs EP Testing in Pediatric Unexplained Syncope. Introduction: Unexplained syncope in the pediatric age group is a common problem that often requires cardiac evaluation. This work‐up is expensive and frequently unrevealing. Electrophysiologic and, more recently, tilt table or orthostatic testing have been used in the evaluation of unexplained syncope. Methods and Results: We undertook to compare the results of these two forms of evaluation in a group of 26 young patients less than 19 years of age with episodes of unexplained syncope. Sixteen of the 26 patients (62%) had an abnormal electrophysiologic study with the majority having either mild sinus node dysfunction or inducible atrial flutter. Four of the 26 patients (16%) were thought to have an abnormality found that was clinically significant (sustained ventricular tachycardia [2], nonsustained ventricular tachycardia/polymorphic premature ventricular contractions [1], and high‐degree atrioventricular block [1]). An abnormal response to orthostatic testing was found in 14 of 26 patients (56%) with 13 of 14 developing syncope at an average standing time of 6.5 minutes. Sixteen patients underwent treatment based on the study findings and follow‐up with an average time of 1.6 years is available on 13 of 16 patients who underwent treatment. Of the nine patients treated for neurally mediated syncope (fludrocortisone [7], beta blocker [1], theophylline [1]), all are asymptomatic. The four patients with an arrhythmic cause of syncope found by electrophysiologic testing are asymptomatic on treatment (antiarrhythmic drug [3], permanent pacing [1]). Conclusion: Orthostatic testing has a higher positive yield than electrophysiologic testing in the evaluation of unexplained syncope in young patients. Orthostatic or tilt table testing should be considered early on in the cardiovascular evaluations of these patients. (J Cardiovasc Electrophysiol, Vol. 3, pp. 418–422, October 1992)
The Frequency‐Dependent Effects of Verapamil on Antegrade Refractory Periods and Conduction in the Atrioventricular Node in Man
Authors: CURTIS ANNE B. , ELLENBOGEN KENNETH , HARTON J. MARCUS , TRAUSS HAROLD C 
Published: May 2007

Frequency‐Dependent Effects of Verapamil. Introduction: The purpose of this study was to examine the frequency‐dependent effects of verapamil on refractoriness and development of conduction block in the human atrioventricular (AV) node. Methods and Results: To more closely simulate conditions thai would be found when the drug is used clinically, the drug was assessed in the absence of autonomic blockade. Antegrade refractory periods were determined in nine patients before and during the administration of verapamil by constant intravenous infusion. In addition, continuous recordings were made during 30‐second sequences of atrial pacing at a long cycle length alternating with sequences at shorter pacing cycle lengths. Mean verapamil levels were constant throughout the study and averaged 111.6 ± 70.7 ng/mL. In the majority of patients, refractoriness in the atrium prevented determination of the effective refractory period of the AV node in the control state. Therefore, although the effective refractory period of the AV node lengthened with decrease in pacing cycle length in the presence of verapamil, the relative contribution of the change in cycle length itself compared to the effect of verapamil could not be determined. A frequency‐ and time‐dependent change in A‐H interval was found with verapamil during atrial pacing. Kinetic analysis of drug effect on AV nodal function was possible in only three patients; in these three patients the mean time constant for onset of block was 2.9 seconds (range 1.9–4.0 sec). In one patient at a pacing cycle length that did not result in second‐degree AV block, transient periods of alternation between short and long A‐H intervals occurred in the presence of verapamil. Conclusion: Verapamil causes frequency‐dependent block of conduction through the AV node. Since changes in autonomic tone will vary from patient to patient, the actual magnitude of the effects of verapamil will vary as well. This may account for some of the interpatient variability seen with clinical use of this drug, despite comparable blood levels. (J Cardiovasc Electrophysiol, Vol. 3, pp. 21–33, February 1992)
Alterations in Repolarization of Cardiac Purkinje Fibers Recovering from Ischemic‐like Conditions:
Authors: Ph.D. GEORGE J. ROZANSKI. , WITT RICHARD C. 
Published: May 2007

Abnormal Repolarization. Introduction: Triggered activity initiated from delayed after‐depolarizations has been proposed as a possible cause of arrhythmias during reperfusion of ischemic myocardium. However, the potential for abnormal repolarization and early afterdepolarizations (EADs) to develop under similar conditions has not been fully explored. Methods and Results: Repolarization of the cell membrane during recovery from ischemic‐like conditions was analyzed from transmembrane recordings in isolated rabbit Purkinje fibers paced at different basic cycle lengths. Preparations were exposed to conditions of hypoxia (defined as oxygen tension < 30 mmHg, high potassium, and zero substrate) plus lactic acidosis (pH 6.7) for 45 minutes followed by recovery in normal Tyrode's solution. Compared to control, action potentials during recovery at basic cycle length of 3,000 msec (n = 11) were characterized by a: (1) −7.2 ± 2.1 mV shift in plateau potential (P < 0.01); (2) 126.1 ± 63.6 msec increase in plateau duration (P < 0.05); and (3) 0.29 ± 0.07 V/sec slowing of the maximum rate of terminal repolarization (phase 3; P < 0.01). These changes were larger when 10 to 20 μM amiloride was added to the hypoxic, acidotic lest solution hut were smaller when tissues were conditioned with hypoxia alone (zero lactate, pH 7.4). Following hypoxia plus acidosis, with or without amiloride, repolarization at long basic cycle lengths was often accompanied by EADs predominantly generated from potentials positive to −40 mV. These afterpotentials were blocked by Ca2+ channel antagonists and exhibited an activation threshold of −26.3 ± l.8 mV (n = 7). Conclusion: These data are consistent with the hypothesis that the combined negative voltage shift in the plateau and increase in its duration lead to the genesis of low membrane potential EADs by allowing reactivation of Ca2+ channels. Moreover, these results suggest that bradycardia‐dependent EADs in Purkinje tissue may underlie arrhythmias in the intact heart during reperfusion of ischemic myocardium by mechanisms that are related in part to the acidosis established during the preceding ischemic conditions.
Intracoronary Ethanol Ablation in Swine:
Authors: HAINES DAVID E. , VEROW ANTHONY F. , SINUSAS ALBERT J. , WHAYNE JAMES G. , DiMARCO JOHN P. 
Published: May 2007

Intracoronary Ethanol Ablation. Introduction: Physical or chemical ablation of arrhythmogenic tissue has been shown to be an effective modality of arrhythmia therapy. Chemical ablation by intracoronary infusion of ethanol into a specific coronary artery bed has been demonstrated, but the characteristics and distribution of necrosis relative to the coronary blood supply have not been delineated. Methods and Results: A total of 40 myocardial lesions were created in 21 pigs by infusion of 1.6 ± 0.6 ml of 50% ethanol and 50% iohexol contrast solution through a 2.7 French infusion catheter advanced into a branch of the left anterior descending or circumflex coronary artery. Prior to ethanol infusion, 5.3 ± 1.2 mCi technetium‐99m (Tc‐99m) methoxyisobutyl isonitrile (sestamibi) was infused into the coronary branch in order to delineate the perfusion bed. After completion of the lesions, each heart was removed, sliced transversely in 5‐mm slices, and stained with nitro blue tetrazolium in order to define the ablation bed. The slices were then imaged with a gamma camera and the area of Tc‐99m sestamibi uptake was defined as the perfusion bed. These respective areas were planimetered for each slice and compared. No difference was observed in hemodynamic parameters between preablation and postablation measures except mean arterial pressure, which fell from 122 ± 22 mmHg to 116 ± 24 mmHg (P = 0.02). Significant ventricular arrhythmias were observed after 60% of the ablations. The mean left ventricular ejection fraction fell from 55%± 9% to 45%± 15% after completion of all ablations. The areas of the ablation beds were related to the areas of the perfusion beds but the correlation was poor (r = 0.41, P = 0.0001). Generally, the ablation bed was smaller than the perfusion bed, but evidence of ethanol reflux was observed in 29% of the lesions resulting in injury beyond the targeted perfusion bed. Conclusions: Intracoronary ethanol ablation is a promising technique for the treatment of arrhythmias. Significant arrhythmias and a decrease in left ventricular ejection fraction are associated with this technique. Lesions are generally produced within the distribution of the targeted coronary bed, but are also frequently associated with reflux to a second vascular distribution.
Relationship Between Different Recovery Curves Representing Rate‐Dependent AV Nodal Function in Rabbit Heart
Authors: BILLETTE JACQUES , AMELLAL FARID , ZHAO JIE , SHRIER ALVIN 
Published: May 2007

Nodal Function and Recovery Measures. Introduction: The rate‐dependent changes in atrioventricular (AV) nodal conduction time show different characteristics depending upon whether the conduction times are plotted against the atrial interval (AA‐recovery curve) or His‐atrial interval (HA‐recovery curve). This study characterizes these differences in the context of controlled changes of nodal functional properties, determines their functional significance, and tests the hypothesis that they are related solely to the nodal conduction time of the last beat (last conduction time) before the premature beat. Methods and Results; Premature nodal conduction times obtained in isolated rabbit heart preparations under various steady‐state and transient conditions were plotted as a function of the corresponding HA and AA intervals, as well as the AA interval corrected for the last conduction time. Under all conditions, the corrected AA‐recovery curve was indistinguishable in shape from the HA‐recovery curve, and as such reflected similar underlying nodal functional properties. Moreover, a selective increase in the last conduction time, induced in the absence of time‐dependent effects associated with the functional property of fatigue, shifted the AA‐recovery but not the HA‐recovery curve upward with respect to the control curve. Conclusion: The last conduction time accounts entirely for differences between AA‐recovery and HA‐recovery curves that otherwise reflect the same underlying nodal functional state. Thus, a consistent assessment of rate‐dependent changes in nodal function can be achieved with either measure of recovery time.
The Influence of Myocardial Systolic Shortening on Action Potential Duration Following Changes in Left Ventricular End‐Diastolic Pressure
Authors: COULSHED DAVID S. , HAINSWORTH ROGER , COWAN J. CAMPBELL 
Published: May 2007

APD and Systolic Shortening. Introduction: Contraction‐excitation feedback may he an important factor in arrhythmogenesis in patients with heart failure. We have previously demonstrated the contrasting effects of raising left ventricular end‐diastolic pressure on action potential duration in dog and guinea pig hearts. The current study was undertaken to assess whether these differing effects might reflect differences in the effect of varying left ventricular end‐diastolic pressure on systolic shortening in the two models. Methods and Results: Two models were studied and compared. In open chest dog hearts and isolated guinea pig hearts, measurements of myocardial segment length were made while left ventricular end‐diastolic pressure was raised and lowered at constant left ventricular peak systolic pressure. Action potentials were also recorded while left ventricular end‐diastolic pressure was changed. The dog hearts were studied further in a manner aimed at reproducing the contraction pattern of the guinea pig hearts. In the in situ dog heart, elevation of left ventricular end‐diastolic pressure, and the consequent increase in end‐diastolic segment length, was accompanied by a marked increase in systolic shortening, such that minimum systolic segment length remained unchanged. Elevation of left ventricular end‐diastolic pressure was accompanied by a prolongation of action potential duration. In the in vitro guinea pig model, elevation of left ventricular end‐diastolic pressure was accompanied by more modest changes in systolic shortening, which were not sufficient to compensate for increased diastolic segment length. Consequently, minimum systolic segment length increased as the hearts dilated. Elevation of left ventricular end‐diastolic pressure was accompanied by a shortening of action potential duration. In a further series of experiments, the effects of increased left ventricular end‐diastolic pressure were studied in the dog model while allowing aortic pressure to rise, thereby restricting systolic shortening. Under these circumstances, the dog model was similar to the guinea pig model, with an increase in left ventricular end‐diastolic pressure causing a shortening of action potential duration. Conclusion: Our results suggest that the effects of preload changes on action potential duration depend on accompanying changes in systolic shortening. This suggests a possible role for contraction‐excitation feedback in arrhythmogenesis in patients with regional wall‐motion abnormalities.
Effects of Incremental Doses of Procainamide in Patients with Sustained Uniform Ventricular Tachycardia
Authors: GRIMM WOLFRAM , CHO JEONG‐GWAN , MARCHLINSKI FRANCIS E. 
Published: May 2007

Procainamide in Patients with Uniform VT. Introduction: Although intravenously administered procainamide has been used extensively during electropharmacologic testing for more than II) years, there is little information available on the effects of incremental dosing of procainamide in patients with inducible, monomorphic ventricular tachycardia (VT). Methods and Results: Twenty‐nine patients with coronary artery disease had sustained monomorphic VT reproducibly induced in the baseline, drug‐free state. Programmed stimulation was repeated 5 minutes after loading infusion (50 mg/min) of 7.5 and 15 mg/kg (all patients) and 22.5 mg/kg of procainamide (15 patients), while maintaining continuous infusion of 0.055, 0.11, and 0.165 mg/kg per minute after each increment in dose, respectively. Corresponding procainamide plasma concentrations were 5.6 ± 2, 10.5 ± 3, and 14.5 ± 3 mg/L before, and 4.7 ± 2, 9.6 ± 3, and 14.6 ± 4 4 mg/L after electrophysiologic study at each increment in dose of procainamide, respectively. Each incremental dose of procainamide resulted in significant prolongation of tachycardia cycle length and QRS duration during sinus rhythm and right ventricular pacing. Five (17%), 7 (24%), and 1 (7%) patients, respectively, had no inducible sustained VT following the incremental dosing of procainamide. Three of five patients who had no inducible VT at 7.5 mg/kg had VT induced again at a higher dose of procainamide. Four of 24 patients whose VT remained inducible at 7.5 mg/kg of procainamide had no VT induced at 15 mg/kg of procainamide. Twelve (41%), 15 (52%), and 6 (40%) patients, respectively, no longer had VT with baseline morphology induced following the incremental dosing of procainamide. VT with new morphology compared to baseline was induced in more than 40% of patients at one or more of the three different procainamide dosing regimens. The mean cycle length of VTs with new morphology was significantly shorter than the cycle length of tachycardias with baseline morphology at each particular dose of procainamide. Conclusion: Similar serum procainamide concentrations before and after programmed stimulation can be achieved at the described dosing regimen. Although 7.5 and 15 mg/kg of procainamide are both effective in suppressing induction of all VT in 20% to 25% of patients, non‐inducibility at a particular dose of procainamide does not predict noninducibility at a respectively higher or lower dose. New morphologies of VT that are frequently faster than VTs with baseline morphology at a particular dose of procainamide can be induced in approximately half of the patients, and the clinical significance of these arrhythmias remains to be determined.