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81.
Introduction: Central venous catheter placement is technically difficult in pediatric population especially in the younger patients. Ultrasound prelocation and/or guidance (UPG) of internal jugular vein (IJV) access has been shown to decrease failure rate and complications related to this invasive procedure. The goal of the present study was to perform a systematic review of the advantages of UPG over anatomical landmarks (AL) during IJV access in children and infants. Material and methods: A comprehensive literature search was conducted to identify clinical trials that focused on the comparison of UPG to AL techniques during IJV access in children and infants. Two reviewers independently assessed each study to meet inclusion criteria and extracted data. Data from each trial were combined to calculate the pooled odds ratio (OR) or the mean differences (MD), and their 95% confidence intervals [CI 95%]. I² statistics were used to assess statistics heterogeneity and to guide the use of fixed or random effect for computation of overall effects. Subgroup analysis was used to clarify the effects of the techniques used (prelocation or guidance) or the experience of practitioners. Results: Literature found five articles. Most of the patients were cardiac surgery patients. In comparison with AL, UPG had no effect on IJV access failure rate (OR = 0.28 [0.05, 1.47], I² = 75%, P = 0.003), the rate of carotid artery puncture (OR = 0.32 [0.06, 1.62], I² = 68%, P = 0.01), haematoma, haemothorax, or pneumothorax occurrence (OR = 0.40 [0.14, 1.13], I² = 17%, P = 0.30, OR = 0.72, OR = 0.81 [0.18, 3.73], I² = 0%, P = 0.94, respectively) and time to IJV access and haemothorax/pneumothorax occurrence. Subgroup analysis found an efficacy of ultrasound when used by novice operators or during intraoperative use. Discussion: This current meta‐analysis does not found the utility of ultrasound during IJV access in children and infants in increasing the success rate and in decreasing complications.  相似文献   
82.
The aim of this study was to compare the characteristics of the first demyelinating event between acute disseminated encephalomyelitis (ADEM) and multiple sclerosis (MS). Children with acute demyelinating disease of the central nervous system and an abnormal brain magnetic resonance image (MRI) were studied. Patients were assigned a final diagnosis after long-term follow-up. Comparisons were made between the MS and ADEM groups. Proposed definitions by the Pediatric MS Study Group were applied to our cohort in retrospect and are discussed. Fifty-two children and adolescents with a documented abnormal brain MRI were identified (24 females, 28 males; mean age 10y 11mo [SD 5y 4mo] range 1y 10mo–19y 7mo). To date, 26 children have been diagnosed with MS, and 24 with ADEM. One child has relapsing neuromyelitis optica and one child has clinically isolated optic neuritis. Follow-up duration was 6 years 8 months in monophasic patients, and 5 years 6 months in relapsing patients. None of the patients with MS had encephalopathy while encephalopathy was present in 42% of patients with ADEM. Cerebrospinal fluid oligoclonal bands, an elevated immunoglobulin and the periventricular perpendicular ovoid lesions correlated with MS outcome. Several clinical characteristics differ between ADEM and MS at first presentation; encephalopathy, when present, strongly suggests the diagnosis of ADEM.  相似文献   
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Presented here is a 39-year-old male patient with no structural heart disease but a ventricular tachycardia with right bundle branch block morphology and right axis deviation, which is responsive to adenosine. The ventricular tachycardia was initiated by ventricular pacing, shown to originate from the mid-anterior free wall region of the left ventricle and terminated by adenosine. Radiofrequency current application at a site where presumed P potentials were recorded eliminated the tachycardia, a finding that suggests that the origin of the tachycardia may be closely related to the anterior fascicle.  相似文献   
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A ten-year-old girl with middle face hypoplasia, cleft lip and palate developed severe hyponatraemia on the first day following surgery. Final diagnosis was inappropriate secretion of antidiuretic hormone (ADH) and complete hormonal investigation revealed partial deficit in growth hormone secretion. The incidence of hormonal deficiency associated to midline facial malformations is discussed.  相似文献   
88.
We describe a nephrogenic adenoma of the bladder in a 14-year-old girl with Turner's syndrome. The patient also had a past history of urological surgery for vesicoureteral reflux. In this case, the multifocal lesions were successfully treated by transurethral resection.  相似文献   
89.
Impedance to Defibrillation Countershock: Does an Optimal Impedance Exist?   总被引:2,自引:0,他引:2  
Defibrillation is thought to occur because of changes in the transmembrane potential that are caused by current flow through the heart tissue. Impedance to electric countershock is an important parameter because it is determined by the magnitude and distribution of the current that flows for a specific shock voltage. The impedance is comprised of resistive contributions from: (Ij extra-tissue sources, which include the defibrillator, leads, and electrodes; (2) tissue sources, which include intracardiac and extra-cardiac tissue; and (3) the interface between electrode and tissue. Tissue sources dominate the impedance and probably contribute to the wide range of impedance values presented to the defibrillation pulse. Hucause impedance is not constant within or between subjects, defibrillators must be designed to accommodate these differences without compromising patient safety or therapeutic efficacy. Experimental investigations in animals and humans suggest that impedance changes at several different time scales ranging from milliseconds to years. These alterations are believed to be a result of both electrochemical and physiological mechanisms. It is commonly thought that impedance is optimized when it has been decreased to a minimum, since this allows the most current flow for a given voltage shock. However, if the impedance is lowered by changing the location or size of the electrodes in such a way that current flow is decreased in part of the heart even though current flow is increased elsewhere, then the total voltage, current, and energy needed for defibrillation may increase, not decrease, even though impedance is decreased. A simple boundary element computer model suggests that the most even distribution of current flow through the heart is achieved for those electrode locations in which the impedance across the heart is at or near the maximum cardiac impedance for any location of these particular electrodes. Thus, the optimum shock impedance is achieved when impedance is minimized for extra-tissue and extra-cardiac tissue sources and is at or near a maximum for intracardiac tissue sources.  相似文献   
90.
The frequency of muscle pain following suxamethonium was studiedin 50 pregnant (8–13 weeks' gestation) and 100 non-pregnantwomen, undergoing laparoscopic tubal ligation. The incidenceof muscle pain in the non-pregnant group was 42%, but only 20%in the pregnant women. The intensity of fasciculation was lessin the pregnant patients. It appears that pregnancy protectsthe patient from suxamethonium pains, even during the firsttrimester.  相似文献   
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