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101.
102.
In pulmonary atresia with a ventricular septal defect and similar congenital heart disorders the pulmonary blood supply is often multifocal. The relative distribution of pulmonary perfusion from individual sources is usually demonstrated by selective angiography. A new technique using a selective injection of radionuclide labelled human albumin microspheres was performed in four patients with a complex pulmonary blood supply. In these cases the physiological distribution of each of the multiple sources of pulmonary perfusion was demonstrated. This is a useful additional technique in the assessment of such patients.  相似文献   
103.
The term “Third World” loosely encompasses a group of middle- and low-income countries. Considerable differences exist in health care delivery and health indices among these countries. The vast majority of children in the Third World do not have health insurance for congential heart disease (CHD). Catheter interventions for CHD are expensive because of installation costs of expensive biplane equipment, the requirement of dedicated personnel, and the need to stock a large inventory of expensive hardware. As a result, many catheter intervention procedures are beyond the reach of the average patient in the developing world. The following cost-effective strategies have evolved in selected institutions that have attempted to perform catheter interventions for CHD at an affordable cost: sharing of space, equipment, and support personnel with a busy adult cardiology program; use of single plane equipment; the development of sedation protocols to reduce the need for anesthesiologists; strategies to reduce procedure time; reuse of hardware through ethylene oxide sterilization; improvisations to use adult hardware items for CHD interventions; judicious case selection; and improvised alternatives to occlusive devices. These strategies may help reduce costs and allow a larger proportion of patients in developing countries with CHD to undergo interventions. However, the safety of these strategies and the cost savings need to be carefully evaluated prospectively.  相似文献   
104.
105.
Background Stress echocardiography is useful for assessing patients with coronary artery disease unable to undergo formal exercise testing. Considerable skill is required to avoid large intra- and inter-observer variability due to poor endocardial definition. Intravenous ultrasound contrast agents are now available which may improve this variability. Aim To study intravenous Sonovue in assessing wall motion score and ejection fraction (EF) during stress echocardiography. Methods Thirty-eight patients undergoing arbutamine stress echocardiography for known or suspected coronary artery disease were studied. Echocardiographic analysis of wall motion score index, endocardial border detection (EBD) and EF was performed at rest and at peak stress before and after intravenous injection of Sonovue, by experienced and inexperienced observers. Results All three observers noted an improvement in endocardial border definition following Sonovue (p=<0.001). At baseline, there was a significant difference in wall motion score index between experienced and inexperienced observers at rest (p=0.01) and at peak stress (p=0.001). Following Sonovue administration this was no longer significant (p=0.07, p=0.114). Intra-observer variability of end diastolic, end systolic volumes (ESV) and EF improved following contrast (p<0.05) at rest and during stress. Conclusion Sonovue significantly improved EBD and reduced intra-observer variability of EF at rest and during peak arbutamine infusion.  相似文献   
106.

OBJECTIVE:

Inflammation plays an important role in the development of chronic lung disease (CLD), which has become a major cause of morbidity in surviving infants less than 1250 g at birth. The authors hypothesized that the progression of this inflammation and, therefore, the establishment of CLD would be decreased with the use of early prophylactic inhaled corticosteroids. Short, and long term respiratory and neurodevelopmental outcomes were also examined.

DESIGN:

A double-blind, randomized placebo controlled trial.

SETTING:

Level-III neonatal intensive care unit.

POPULATION STUDIED:

Sixty infants less than 1250 g at birth, diagnosed with respiratory distress syndrome and requiring ventilatory support at 72 h of age were enrolled in the study.

INTERVENTION:

Infants enrolled received either placebo or beclomethasone diproprionate by a metered dose inhaler, which was used in-line with the ventilator circuit while the infant was ventilated and then via a spacer until 28 days of age.

RESULTS:

Thirty infants were given beclomethasone and 30 were given placebo. There were two deaths in each group. Among the surviving infants, the frequency of moderate-to-severe CLD was 17% in each study group. Mean time to extubation was not different for beclomethasone compared with placebo at 16.4 and 12.5 days (P=0.12), respectively. The requirement for intravenous corticosteroids was lower in the beclomethasone-treated group (RR 0.67, 95% CI 0.43 to 1.04), although this difference was not statistically significant. The incidence of growth failure, infection and intraventricular hemmorhage did not differ between the two groups. Long term outcomes were not different with respect to the incidence of respiratory re-admissions, cerebral palsy, developmental delay, blindness or deafness.

CONCLUSIONS:

Early treatment with inhaled beclomethasone diproprionate did not reduce the incidence of CLD or decrease the duration of mechanical ventilation. The decrease in intravenous corticosteroid use was not statistically significant. Long term outcome was not affected.  相似文献   
107.
108.
BACKGROUND: Registered dietitian/registered nurse (RD/RN) teams were created to place small bowel feeding tubes (SBFT) at the bedside in intensive care unit (ICU) patients using an electromagnetic tube placement device (ETPD). The primary objective of this study was to evaluate the safety of placing feeding tubes at the ICU bedside using an ETPD. Secondary outcomes included success rate, cost, and timeliness of feeding initiation. METHODS: Data were collected prospectively on 20 SBFT blind placements in ICU patients (control group). After implementing a protocol for RD/RN teams to place SBFTs with an ETPD, 81 SBFTs were placed (study group). Complications, success rate, number of x-rays after tube placement, x-ray cost, and time from physician order to initiation of feedings were compared between the groups. RESULTS: No adverse events occurred in either group. Successful SBFT placement was 63% (12/19) in the control group and 78% (63/81) in the study group (not significant, NS). The median time between physician order for tube placement and feeding initiation decreased from 22.3 hours (control group) to 7.8 hours (study group, p = .003). The median number of x-rays to confirm correct placement was 1 in the study group compared with 2 in the control group (p = .0001), resulting in a 50% decrease in the mean cost for x-rays. CONCLUSIONS: No adverse events occurred with the implementation of bedside feeding tube placement using an ETPD. In addition, SBFT placement with an ETPD by designated ICU RD/RN teams resulted in lower x-ray costs and more timely initiation of enteral feedings compared with blind placement.  相似文献   
109.
The breast is a complex anatomical structure where achieving a homogeneous dose distribution with radiation treatment is difficult. Despite obvious similarities in the approach to such treatment (using tangents) there is variation in the process of simulation, planning and treatment between radiation oncologists. Previous Australasian studies in the treatment of lung cancer, prostate cancer and Hodgkin’s disease highlighted considerable variation in many areas of treatment. As part of a multicentre breast phantom study involving 10 radiation oncology departments throughout New South Wales (NSW) and the Australian Capital Territory (ACT), a 22-question survey was distributed. The aim of the survey was to assess the extent of variation in the approach to the simulation, planning and treatment of early breast cancer using tangents. Responses from 10 different radiation oncology departments revealed variation in most areas of the survey. There is no reason to assume similar variations do not occur Australasia wide. Studies involving overseas radiation oncologists also reveal a wide variation in treating early breast cancer. The consequences of such variations remain unclear.  相似文献   
110.
A patient with progressive osteolysis of the carpal and tarsal bones with glomerulonephritis of unusual severity is described. There was a notable absence of osteodystrophy in this and other reported cases who had chronic renal failure.  相似文献   
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