Elimination of gaseous microemboli from cardiopulmonary bypass using hypobaric oxygenation.

BACKGROUND: Numerous gaseous microemboli (GME) are delivered into the arterial circulation during cardiopulmonary bypass (CPB). These emboli damage end organs through multiple mechanisms that are thought to contribute to neurocognitive deficits after cardiac surgery. Here, we use hypobaric oxygenation to reduce dissolved gases in blood and greatly reduce GME delivery during CPB. METHODS: Variable subatmospheric pressures were applied to 100% oxygen sweep gas in standard hollow fiber microporous membrane oxygenators to oxygenate and denitrogenate blood. GME were quantified using ultrasound while air embolism from the surgical field was simulated experimentally. We assessed end-organ tissues in swine postoperatively using light microscopy. RESULTS: Variable sweep gas pressures allowed reliable oxygenation independent of carbon dioxide removal while denitrogenating arterial blood. Hypobaric oxygenation produced dose-dependent reductions of Doppler signals produced by bolus and continuous GME loads in vitro. Swine were maintained using hypobaric oxygenation for 4 hours on CPB with no apparent adverse events. Compared with current practice standards of oxygen/air sweep gas, hypobaric oxygenation reduced GME volumes exiting the oxygenator (by 80%), exiting the arterial filter (95%), and arriving at the aortic cannula (∼100%), indicating progressive reabsorption of emboli throughout the CPB circuit in vivo. Analysis of brain tissue suggested decreased microvascular injury under hypobaric conditions. CONCLUSIONS: Hypobaric oxygenation is an effective, low-cost, common sense approach that capitalizes on the simple physical makeup of GME to achieve their near-total elimination during CPB. This technique holds great potential for limiting end-organ damage and improving outcomes in a variety of patients undergoing extracorporeal circulation.

A pilot food store intervention in the Republic of the Marshall Islands.

To improve diet and reduce risk for obesity and chronic disease, we developed, implemented and evaluated a pilot intervention trial with 23 large and small food stores in the Republic of the Marshall Islands (12 intervention, 11 control). The intervention included both mass media (radio announcements, newspaper ads, video) and in-store (cooking demonstrations, taste tests, shelf labeling) components. Consumer exposure to the mass media components was high (65% had heard half or more of the radio announcements, 74% had seen at least one of the newspaper ads). Consumer exposure to the in-store components of the intervention was moderate (61% attended at least one cooking demonstrations, 59% received at least one recipe card). After adjustment for age, sex and education level, increased exposure to the intervention was associated with higher diabetes knowledge (p<0.05) and label reading knowledge (p<0.05), but not with increased self-efficacy for performing promoted healthy behaviors. The intervention was associated with increased purchasing of certain promoted foods (p<0.005), including oatmeal, turkey chili, fish, canned fruit and local vegetables. It was also associated with improvements in healthiness of cooking methods (p<0.05). Food store centered interventions have great potential for changing cognitive and behavioral factors relating to food choice and preparation, and may contribute to lessening the burden of diet-related chronic disease worldwide.

Development and implementation of a food store-based intervention to improve diet in the Republic of the Marshall Islands.

Effective approaches for the prevention and reduction of obesity and obesity-related chronic diseases are urgently needed. Food store-centered programs represent one approach that may be both effective and sustainable. The authors developed a food store-based intervention in the Marshall Islands using qualitative and quantitative formative research methods, including a store usage survey (n = 184) and in-depth interviews with large-store managers (n = 13), small-store managers (n = 7), customers (n = 10), and community leaders (n = 4). This process was followed up by development and piloting of specific intervention components and workshops to finalize materials. The final intervention combined mass media (newspaper articles, video, radio announcements) and in-store components (shelf labels, cooking demonstrations, posters, recipe cards) and had high store-owner support and participation. High levels of exposure to the intervention were achieved during the 10-week period of implementation. This model for developing food store-based interventions is applicable to other settings.

Macro- and microlevel processes affect food choice and nutritional status in the republic of the marshall islands.

Despite its relative isolation from the world stage and lack of resources, the Marshall Islands serve as an example of the interaction between global political power, macroeconomic forces and local cultural factors. At the national level, patterns of food importation and government programs encourage the consumption of high fat foods. These factors have fostered dependency on Western foods and a loss of traditional food practices. Beliefs come into play as microlevel factors that influence food choice and aspects of lifestyle. Nearly three quarters of women are overweight or obese in this setting. Obesity in women is associated with greater age, higher education and more imported food consumption. Over a third of children ages 1-5 y are stunted, with stunting associated with worse economic status, less active feeding, increased consumption of imported foods and urban residence. What can be done at the microlevel is constrained by macrolevel factors of disempowerment. In this way, issues of power and belief are played out in the bodies of individuals.