No abstract

No abstract

The need to quantify blood flow through the heart has led to the development of different techniques for its measurement. The 3 main approaches are the Fick method, dye dilution, and thermodilution techniques. The latter 2 are based on the use of indicators that indirectly quantify blood flow. These have slowly been developed over centuries, from the concept of measuring blood flow, to a technique, and its clinical utility. Thermodilution is the most popular dilution method used for measuring cardiac output (CO) in the clinical setting. The information obtained during this procedure is relevant in the process of clinical decision making in patients with critical illness, valvular heart disease, and congestive heart failure. The technique increased in popularity in the early 1970’s after Swan and Ganz invented the pulmonary artery catheter that simplified thermodilution enough to utilize it as a bedside procedure. This was only possible with simple yet clever engineering methods that are not commonly known in the medical community. Despite these advancements, the concept of measuring CO by dilution techniques is one where its optimal use in the clinical setting continues to be an area of investigation. The thermodilution concept and the mechanism of measuring CO will be discussed in the following review.

BackgroundGuatemala is currently undergoing an epidemiologic transition. Preventive services are key to reducing the burden of non-communicable diseases, and smoking counseling and cessation are among the most cost-effective and wide-reaching strategies. Internal medicine physicians are fundamental to providing such services, and their knowledge is a cornerstone of non-communicable disease control.MethodsA national cross-sectional survey was conducted in 2011 to evaluate knowledge of clinical preventive services for non-communicable diseases. Interns, residents, and attending physicians of the internal medicine departments of all teaching hospitals in Guatemala completed a self-administered questionnaire. Participants’ responses were contrasted with the Guatemalan Ministry of Health (MoH) prevention guidelines and the US Preventive Services Task Force (USPSTF) recommendations. Analysis compared knowledge of recommendations within and between hospitals.ResultsIn response to simulated patient scenarios, all services were recommended by more than half of physicians regardless of MoH or USPSTF recommendations. Prioritization was adequate according to the MoH guidelines but not including other potentially effective services (e.g. colorectal cancer and lipid disorder screenings). With the exception of colorectal and prostate cancer screening, less frequently recommended by interns, there was no difference in recommendation rates by level.ConclusionGuatemalan internal medicine physicians’ knowledge on preventive services recommendations for non-communicable diseases is limited, and prioritization did not reflect cost-effectiveness. Based on these data we recommend that preventive medicine training be strengthened and development of evidence-based guidelines for low-middle income countries be a priority.