RESUMO
OBJECTIVE: The aim of this study was to develop a tool to visualize and quantify hemodynamic information, such as hemoglobin concentration and hematocrit, within microvascular networks recorded in vivo using intravital video microscopy. Additionally, we aimed to facilitate the 3-D reconstruction of the microvascular networks. METHODS: Digital images taken from an intravital video microscopy preparation of the extensor digitorum longus muscle in rats for 25 capillary segments were used. The developed algorithm was used to delineate capillaries of interest, calculate the optical density for each pixel in the image, and reconstruct the 3-D capillary geometry using the calculated light path-lengths. Subsequently, the mean corpuscular hemoglobin concentration (MCHC), hemoglobin concentration, and hematocrit for these capillaries were calculated. We evaluated the hematocrit values determined by our methodology by comparing them to those obtained using a previously published method. RESULTS: The hematocrit values from the proposed optical method were strongly correlated with those calculated using published methods r2 (25) = .92, p < .001, and demonstrated excellent agreement with a mean difference of 1.3% and a coefficient of variation (CV) of 11%. The average MCHC, hemoglobin concentration, and light path-lengths were 23.83 g/dl, 8.06 g/dl, and 3.92 µm, respectively. CONCLUSION: The proposed methodology can quantify hemodynamic measurements and produce functional images for visualization of the microcirculation in vivo.
Assuntos
Capilares , Músculo Esquelético , Animais , Ratos , Capilares/diagnóstico por imagem , Capilares/fisiologia , Hematócrito , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/irrigação sanguínea , Microcirculação/fisiologia , HemoglobinasRESUMO
OBJECTIVES: Reducing unnecessary tests that do not enhance quality can promote health-care value. Glycated hemoglobin (A1C) is often ordered at a frequency exceeding the recommendation of once every 3 months. We conducted a quality improvement (QI) initiative aimed to reduce unnecessary repeat testing by 75% at a tertiary care academic hospital. METHODS: A retrospective baseline analysis was conducted on laboratory data from 2019 that enumerated unnecessary A1C tests, defined as repeat tests ordered within 60 days. A multifaceted change intervention with iterative plan-do-study-act cycles was introduced in March 2019 to educate providers and to automatically cancel A1C tests requested within 60 days. Monthly totals of A1C testing processed were plotted on statistical process control charts. RESULTS: In 2019, 11% of all A1C tests ordered were unnecessary. Between March 2020 and January 2021, 11% of the tests (N=14,247 tests) were unnecessary, of which 84% were cancelled with our intervention. Providers in cardiology and nephrology accounted for over half (55%) of the unnecessary tests ordered. CONCLUSIONS: A 2-pronged approach informed by root-cause analysis, and comprised of gatekeeping and provider education, can effectively promote resource stewardship for reducing unnecessary A1C testing.