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We present a case of supraventricular tachycardia affecting one fetus in a twin pregnancy. Before and after treatment with flecainide and cardioversion, we examined conduction times and heart rate variability (HRV) in both twins on the basis of magnetocardiography. Cardiac conduction times increased in both fetuses but HRV showed opposing effects with a number of HRV measures. This case demonstrates that magnetocardiography not only enables identification of fetal arrhythmia, but also permits the investigation of the effects of antiarrhythmic treatment on the conductive system as well as on interaction with the autonomic nervous system.  相似文献   
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Objective: To assess the interaction between pulmonary hemodynamics and respiratory mechanics during acute pulmonary hypertension. Patients: Ventilated and paralysed children treated with inhaled nitric oxide because of post-operative pulmonary hypertension. Interventions: Weaning of inhaled nitric oxide. Measurements: Air flow and airway pressure, calculation of dynamic respiratory system compliance and respiratory system resistance for each breath by multiple linear regression. Results: In four patients, increases in pulmonary arterial pressure from 26.1 to 56.7 mmg (p < 0.001) during weaning off nitric oxide were associated with decreases in tidal volume (from 9.7 → 8.2 ml/kg, p < 0.01) and reductions in dynamic respiratory system compliance (from 0.52 → 0.34 cmH20/ml/kg, p < 0.001), while respiratory system resistance was unchanged. Conclusions: Impaired ventilation during acute pulmonary hypertension is predominantly related to a reduction in respiratory system compliance. Received: 26 March 1998 Final revision received: 9 June 1998 Accepted: 30 July 1998  相似文献   
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Introduction

Recent clinical data suggest that early administration of vasopressin analogues may be advantageous compared to a last resort therapy. However, it is still unknown whether vasopressin and terlipressin are equally effective for hemodynamic support in septic shock. The aim of the present prospective, randomized, controlled pilot trial study was, therefore, to compare the impact of continuous infusions of either vasopressin or terlipressin, when given as first-line therapy in septic shock patients, on open-label norepinephrine requirements.

Methods

We enrolled septic shock patients (n = 45) with a mean arterial pressure below 65 mmHg despite adequate volume resuscitation. Patients were randomized to receive continuous infusions of either terlipressin (1.3 μg·kg-1·h-1), vasopressin (.03 U·min-1) or norepinephrine (15 μg·min-1; n = 15 per group). In all groups, open-label norepinephrine was added to achieve a mean arterial pressure between 65 and 75 mmHg, if necessary. Data from right heart and thermo-dye dilution catheterization, gastric tonometry, as well as laboratory variables of organ function were obtained at baseline, 12, 24, 36 and 48 hours after randomization. Differences within and between groups were analyzed using a two-way ANOVA for repeated measurements with group and time as factors. Time-independent variables were compared with one-way ANOVA.

Results

There were no differences among groups in terms of systemic and regional hemodynamics. Compared with infusion of.03 U of vasopressin or 15 μg·min-1 of norepinephrine, 1.3 μg·kg-1·h-1 of terlipressin allowed a marked reduction in catecholamine requirements (0.8 ± 1.3 and 1.2 ± 1.4 vs. 0.2 ± 0.4 μg·kg-1·min-1 at 48 hours; each P < 0.05) and was associated with less rebound hypotension (P < 0.05). At the end of the 48-hour intervention period, bilirubin concentrations were higher in the vasopressin and norepinephrine groups as compared with the terlipressin group (2.3 ± 2.8 and 2.8 ± 2.5 vs. 0.9 ± 0.3 mg·dL-1; each P < 0.05). A time-dependent decrease in platelet count was only observed in the terlipressin group (P < 0.001 48 hours vs. BL).

Conclusions

The present study provides evidence that continuous infusion of low-dose terlipressin – when given as first-line vasopressor agent in septic shock – is effective in reversing sepsis-induced arterial hypotension and in reducing norepinephrine requirements.

Trial registration

ClinicalTrial.gov NCT00481572.  相似文献   
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