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91.
92.
Propranolol has been used successfully in a limited number of children with infantile hemangiomas (IHs). This study describes the efficacy and adverse effects of propranolol in IH. Seventy-one infants with IHs were treated with oral propranolol, administered at a dose of 2 mg/kg/day, for at least 12 weeks. A photograph-based severity scoring assessment was performed by five observers to evaluate efficacy, utilizing a score of 10 as the original IHs before treatment and 0 as completely normal skin. The mean of the five independent measurements was used in the analysis. Propranolol was a rapid and effective treatment for IHs at 4 weeks (P < 0.001), at 8 weeks (P < 0.001 compared with the value at 4 weeks), at 12 weeks (P < 0.05 compared with the value at 8 weeks), and thereafter up to 32 weeks (P < 0.01 compared with the value at 16 weeks). The response of IHs to propranolol was similar regardless of gender, age at the onset of treatment, type of involvement (local and extended), facial segments affected, special locations (eyelid, nasal tip, and parotid regions), ulceration, and depth of IHs. In the series of patients in this study, oral propranolol at a dosage of 2 mg/kg/day was a well-tolerated and effective treatment for IHs.  相似文献   
93.
Clinically overt hypertrophic cardiomyopathy is the most common cause of sudden unexpected death in childhood and has significantly higher sudden death mortality in the 8‐ to 16‐year age range than in the 17‐ to 30‐year age range. A combination of electrocardiographic risk factors (a limb‐lead ECG voltage sum >10 mV) and/or a septal wall thickness >190% of upper limit of normal for age (z‐score > 3.72) defines a paediatric high‐risk patient with great sensitivity. Syncope, blunted blood pressure response to exercise, non‐sustained ventricular tachycardia and a malignant family history are additional risk factors. Of the medical treatments used, only beta‐blocker therapy with lipophilic beta‐blockers (i.e. propranolol, metoprolol or bisoprolol) have been shown to significantly reduce risk of sudden death, with doses ≥6 mg/kg BW in propranolol equivalents giving around a tenfold reduction in risk. Disopyramide therapy is a very useful adjunct to beta‐blockers to improve prognosis in those patients that have dynamic outflow obstruction in spite of large doses of beta‐blocker, and its use in patients with hypertrophic cardiomyopathy is not associated with significant pro‐arrhythmia mortality. Calcium‐channel blockers increase the risk of heart failure‐associated death in hypertrophic cardiomyopathy (HCM) patients with severe generalized hypertrophy and should be avoided in such patients. Amiodarone does not protect against sudden death, and long‐term use in children usually has to be terminated because of side effects. Therapy with internal cardioverter defibrillator implantation has high paediatric morbidity, 27% incidence of inappropriate shocks, and does not absolutely protect against mortality but is indicated as secondary prevention or in very high‐risk patients.  相似文献   
94.
Atrial fibrillation was induced during an electrophysiology study in 10 patients with the Wolff-Parkinson-White (WPW) syndrome, after determination of baseline properties of the accessory atrioventricular (AV) connection; intravenous propranolol (0.2 mg/kg) was then administered. Atrial fibrillation terminated during the drug infusion in three patients, allowing determination of propranolol's effects on conduction and refractoriness during sinus rhythm, before atrial fibrillation was reinduced. In these three patients propranolol had no effect on refractoriness or conduction properties of the accessory AV connection during sinus rhythm. The mean ventricular rate during atrial fibrillation was slowed by 15–56 beats/min in six patients, had no effect on the mean rate in three patients, and markedly increased the ventricular rate (203 to 267 beats/min) in one patient. In this patient, 54% of QRS complexes during atrial fibrillation were narrow, compared to 0–25% in the other patients. Propranolol reduced the percentage of QRS complexes that were narrow from 13 ± 16% to 1 ± 2% (mean ± standard deviation, p < 0.05). We conclude that propranolol may slow the ventricular rate during atrial fibrillation in some patients with the WPW syndrome, probably by blockcing the effects of adrenergic activation. However, propranolol should not be used in patients with the WPW syndrome who have atrial fibrillation, if most QRS complexes during atrial fibrillation are preexcited. When a large percentage of QHS complexes are narrow, propranolol may increase the ventricular rate, probably by eliminating concealed retrograde conduction in the accessory AV connection.  相似文献   
95.
BackgroundOral propranolol (Pr) must be administered until the end of the proliferation phase of infantile haemangioma (IH). This phase may be difficult to assess, particularly where a deep component is involved. Doppler ultrasound scans (DUS), which identify vascular activity (VA), could assist the clinician in making the correct therapeutic decision (CTD).Patients and methodsAll children with IH treated with Pr for at least 3 months and up to the age of 9 months, and who also underwent DUS, were enrolled in this retrospective, single-centre, observational study. The quality of DUS as a binary diagnostic test for IH proliferation was assessed, together with its value in deciding whether to discontinue Pr (at the end of the presumed proliferation phase) or resume this drug (in the case of suspected recurrence).ResultsA total of 29 children were enrolled and 45 DUS were performed. Thirty-nine (87%) DUS were of high quality (80% sensitivity, 95% specificity) and made a major, moderate, or minimal contribution to the CTD in respectively 20%, 60% and 7% of cases.DiscussionDUS proved to be a high-value tool. They were essential in some cases of IH, mainly periocular and localised forms, and those involving deep components, in which the question of discontinuing Pr arose (age > 1 year) and where clinical examination had not been sufficient to make the CTD. Furthermore, in the vast majority of cases, they provide a helpful examination and complement clinical findings in terms of patient follow-up and reaching a CTD.ConclusionDUS is an effective and complementary tool to clinical investigation.  相似文献   
96.
We describe a 3‐month‐old child with an infantile hemangioma on the forehead with a blanched macule provoked by topical treatment with propranolol. This observation demonstrates that topically applied (non‐selective) beta‐blockers may induce blanched macules at the site of application, a side effect due to peripheral vasoconstriction of blood vessels by non‐selective beta‐2 blockade. This side effect was linked due to overuse and was reversible. This case illustrates the importance of providing thorough instructions regarding topical propranolol application.  相似文献   
97.
目的 观察普萘洛尔治疗婴幼儿血管瘤的临床疗效.方法 回顾性分析在我院门诊收治的血管瘤婴儿300例,其中观察组150例口服普萘洛尔治疗,对照组150例口服泼尼松治疗.2组患儿定期门诊复诊,采用直观、手工测量、彩色多普勒超声或MRI等方法动态观察患者血管瘤范围、颜色变化、质地及不良反应.结果 观察组与对照组相比,瘤体明显缩...  相似文献   
98.
BACKGROUND: Lactacidemia is often seen under stress conditions including septic shock in the newborn. Under stress conditions, plasma catecholamine concentrations are increased and play an important role in lactate metabolism. Our previous study shows that perinatal feeding of omega-3 polyunsaturated fatty acid enriched diet (omega-3PUFA) attenuates lactacidemia of endotoxic shock in 10-day-old rats. In the omega-6 fatty acids series, decosapentanoic acid, two series prostaglandins and four series leukotrienes are synthesized through linoleic acids. As plasma lactate concentration correlates with the outcome of septic shock in the newborn, it is important to understand the effects of omega-3PUFA on lactate metabolism. Thus, we tested the hypothesis that perinatal feeding of omega-3 polyunsaturated fatty acid enriched diet (omega-3PUFA) alters responses to catecholamines and attenuates the stress-induced lactacidemia in 10-day-old rats. METHODS: Ten-day-old rats which perinatally fed omega-3PUFA. Lactacidemia was induced by swimming for 5 min. Ten-day-old rats which perinatally fed omega-6PUFA were controls. Omega-6 fatty acids series are contained in animal fats and corn oil. Adrenergic blockers were used to assess roles of catecholamines in swimming-induced lactacidemia. RESULTS: Swimming increased plasma lactate concentration less (P<0.05) in rats fed omega-3PUFA than rats fed omega-6PUFA. Swimming increased plasma concentrations of glucose and glucagon, cyclic adenosine monophosphate (cAMP) concentration and phosphoenolypruvate carboxykinase mRNA in the liver, and cAMP concentration in the hindlimb muscle more (P<0.05) in rats fed omega-3PUFA than in rats fed omega-6PUFA. Phentolamine and propranolol enhanced swim-induced lactacidemia in the omega-3PUFA group, while they decreased the lactacidemia in the omega-6PUFA group. Propranolol enhanced swimming-induced hyperglycemia in the omega-6PUFA group more than in the omega-3PUFA group. CONCLUSIONS: Omega-3PUFA might increase beta-adrenergic response in the liver and increase gluconeogenesis in response to stress, resulting in decreased lactacidemia.  相似文献   
99.
盐酸普萘洛尔透皮吸收膜剂的研制   总被引:2,自引:0,他引:2  
用离体大鼠皮肤为渗透屏障,研究了盐酸普萘洛尔在杜促灵、油酸、Azone作用下的透皮效果.在盐酸普萘洛尔的饱和水溶液中促进效果大小依次为50g/LAzone,100g/L杜促灵、200g/L.杜促灵、50g/L杜促灵、50g/L油酸,并且杜促灵的滞后时间比Azone短.在聚乙烯醇为成膜材料,100g/L杜促灵为促进剂制成的膜剂用于家兔皮肤进行药物动力学研究.结果表明,盐酸普萘洛尔膜剂透皮给药后以零级方式吸收进入血液循环.  相似文献   
100.
Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H2O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg−1 followed by 0.15 mg · kg−1 · h−1, n=8) or verapamil (0.1 mg · kg−1 followed by 0.3 mg · kg−1 · h−1, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.  相似文献   
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