JOAO BATISTA BORGES SOBRINHO DORINI
Projetos de Pesquisa
Unidades Organizacionais
LIM/09 - Laboratório de Pneumologia, Hospital das Clínicas, Faculdade de Medicina
3 resultados
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- Validation of bohr dead space measured by volumetric capnography(2012) TUSMAN, G.; SUAREZ-SIPMANN, F.; BORGES, J. B.; HEDENSTIERNA, G.; BOHM, S. H.Purpose: Bohr’s dead space (VDBohr) is commonly calculated using end-tidal CO2 instead of the true alveolar partial pressure of CO2 (PACO2). The aim of this work was to validate VDBohr using PACO2 derived from volumetric capnography (VC) against VDBohr with PACO2 values obtained from the standard alveolar air formula. Methods: Expired gases of seven lung-lavaged pigs were analyzed at different lung conditions using mainstream VC and multiple inert gas elimination technique (MIGET). Paco2 was determined by VC as the midpoint of the slope of phase III of the capnogram, while mean expired partial pressure of CO2 (PeCO2) was calculated as the mean expired fraction of CO2 times the barometric minus the water vapor pressure. Miget estimated expired CO2 output (VCO2) and PeCO2 by its V/Q algorithms. Then, PACO2 was obtained applying the alveolar air formula (PACO2 = VCO2/alveolar ventilation). Results: We found close linear correlations between the two methods for calculating both PACO2 (r = 0.99) and VDBohr (r = 0.96), respectively (both p\0.0001). Mean PACO2 from VC was very similar to the one obtained by MIGET with a mean bias of -0.10 mmHg and limits of agreement between -2.18 and 1.98 mmHg. Mean VDBohr from VC was close to the value obtained by MIGET with a mean bias of 0.010 ml and limits of agreement between -0.044 and 0.064 ml. Conclusions: VDBohr can be calculated with accuracy using volumetric capnography. © Springer-Verlag Berlin Heidelberg 2006, 2009, 2012.
- Bedside estimation of recruitable alveolar collapse and hyperdistension by electrical impedance tomography(2012) COSTA, E. L. V.; BORGES, J. B.; MELO, A.; SUAREZ-SIPMANN, F.; TOUFEN, C. Jr.; BOHM, S. H.; AMATO, M. B. P.Objective: To present a novel algorithm for estimating recruitable alveolar collapse and hyperdistension based on electrical impedance tomography (EIT) during a decremental positive end-expiratory pressure (PEEP) titration. Design: Technical note with illustrative case reports. Setting: Respiratory intensive care unit. Patient: Patients with acute respiratory distress syndrome. Interventions: Lung recruitment and PEEP titration maneuver. Measurements and results: Simultaneous acquisition of EIT and X-ray computerized tomography (CT) data. We found good agreement (in terms of amount and spatial location) between the collapse estimated by EIT and CT for all levels of PEEP. The optimal PEEP values detected by EIT for patients 1 and 2 (keeping lung collapse \10%) were 19 and 17 cmH2O, respectively. Although pointing to the same non1dependent lung regions, EIT estimates of hyperdistension represent the functional deterioration of lung units, instead of their anatomical changes, and could not be compared directly with static CT estimates for hyperinflation. Conclusions: We described an EIT-based method for estimating recruitable alveolar collapse at the bedside, pointing out its regional distribution. Additionally, we proposed a measure of lung hyperdistension based on regional lung mechanics. © Springer-Verlag Berlin Heidelberg 2006, 2009, 2012.
bookPart SARA: fisiopatologia e estratégia ventilatória(2016) BORGES, João Batista; AMATO, Marcelo; VICTORINO, Josué