JOAO BATISTA BORGES SOBRINHO DORINI
Projetos de Pesquisa
Unidades Organizacionais
LIM/09 - Laboratório de Pneumologia, Hospital das Clínicas, Faculdade de Medicina
14 resultados
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- How large is the lung recruitability in early acute respiratory distress syndrome: a prospective case series of patients monitored by computed tomography(2012) MATOS, Gustavo F. J. de; STANZANI, Fabiana; PASSOS, Rogerio H.; FONTANA, Mauricio F.; ALBALADEJO, Renata; CASERTA, Raquel E.; SANTOS, Durval C. B.; BORGES, Joao Batista; AMATO, Marcelo B. P.; BARBAS, Carmen S. V.Introduction: The benefits of higher positive end expiratory pressure (PEEP) in patients with acute respiratory distress syndrome (ARDS) have been modest, but few studies have fully tested the ""open-lung hypothesis"". This hypothesis states that most of the collapsed lung tissue observed in ARDS can be reversed at an acceptable clinical cost, potentially resulting in better lung protection, but requiring more intensive maneuvers. The short-/middle-term efficacy of a maximum recruitment strategy (MRS) was recently described in a small physiological study. The present study extends those results, describing a case-series of non-selected patients with early, severe ARDS submitted to MRS and followed until hospital discharge or death. Methods: MRS guided by thoracic computed tomography (CT) included two parts: a recruitment phase to calculate opening pressures (incremental steps under pressure-controlled ventilation up to maximum inspiratory pressures of 60 cmH(2)O, at constant driving-pressures of 15 cmH(2)O); and a PEEP titration phase (decremental PEEP steps from 25 to 10 cmH2O) used to estimate the minimum PEEP to keep lungs open. During all steps, we calculated the size of the non-aerated (-100 to +100 HU) compartment and the recruitability of the lungs (the percent mass of collapsed tissue re-aerated from baseline to maximum PEEP). Results: A total of 51 severe ARDS patients, with a mean age of 50.7 years (84% primary ARDS) was studied. The opening plateau-pressure was 59.6 (+/- 5.9 cmH(2)O), and the mean PEEP titrated after MRS was 24.6 (+/- 2.9 cmH(2)O). Mean PaO2/FiO(2) ratio increased from 125 (+/- 43) to 300 (+/- 103; P < 0.0001) after MRS and was sustained above 300 throughout seven days. Non-aerated parenchyma decreased significantly from 53.6% (interquartile range (IQR): 42.5 to 62.4) to 12.7% (IQR: 4.9 to 24.2) (P < 0.0001) after MRS. The potentially recruitable lung was estimated at 45% (IQR: 25 to 53). We did not observe major barotrauma or significant clinical complications associated with the maneuver. Conclusions: MRS could efficiently reverse hypoxemia and most of the collapsed lung tissue during the course of ARDS, compatible with a high lung recruitability in non-selected patients with early, severe ARDS. This strategy should be tested in a prospective randomized clinical trial.
- Real-time ventilation and perfusion distributions by electrical impedance tomography during one-lung ventilation with capnothorax(2015) REINIUS, H.; BORGES, J. B.; FREDEN, F.; JIDEUS, L.; CAMARGO, E. D. L. B.; AMATO, M. B. P.; HEDENSTIERNA, G.; LARSSON, A.; LENNMYR, F.BackgroundCarbon dioxide insufflation into the pleural cavity, capnothorax, with one-lung ventilation (OLV) may entail respiratory and hemodynamic impairments. We investigated the online physiological effects of OLV/capnothorax by electrical impedance tomography (EIT) in a porcine model mimicking the clinical setting. MethodsFive anesthetized, muscle-relaxed piglets were subjected to first right and then left capnothorax with an intra-pleural pressure of 19cm H2O. The contra-lateral lung was mechanically ventilated with a double-lumen tube at positive end-expiratory pressure 5 and subsequently 10cm H2O. Regional lung perfusion and ventilation were assessed by EIT. Hemodynamics, cerebral tissue oxygenation and lung gas exchange were also measured. ResultsDuring right-sided capnothorax, mixed venous oxygen saturation (P=0.018), as well as a tissue oxygenation index (P=0.038) decreased. There was also an increase in central venous pressure (P=0.006), and a decrease in mean arterial pressure (P=0.045) and cardiac output (P=0.017). During the left-sided capnothorax, the hemodynamic impairment was less than during the right side. EIT revealed that during the first period of OLV/capnothorax, no or very minor ventilation on the right side could be seen (33% vs. 97 +/- 3%, right vs. left, P=0.007), perfusion decreased in the non-ventilated and increased in the ventilated lung (18 +/- 2% vs. 82 +/- 2%, right vs. left, P=0.03). During the second OLV/capnothorax period, a similar distribution of perfusion was seen in the animals with successful separation (84 +/- 4% vs. 16 +/- 4%, right vs. left). ConclusionEIT detected in real-time dynamic changes in pulmonary ventilation and perfusion distributions. OLV to the left lung with right-sided capnothorax caused a decrease in cardiac output, arterial oxygenation and mixed venous saturation.
- A Model for Military-Civilian Collaboration in Academic Surgery Beyond Trauma Care(2017) BORGES, Joao Batista; AMATO, Marcelo B. P.; HEDENSTIERNA, Goran
- Does Regional Lung Strain Correlate With Regional Inflammation in Acute Respiratory Distress Syndrome During Nonprotective Ventilation? An Experimental Porcine Study(2018) RETAMAL, Jaime; HURTADO, Daniel; VILLARROEL, Nicolas; BRUHN, Alejandro; BUGEDO, Guillermo; AMATO, Marcelo Britto Passos; COSTA, Eduardo Leite Vieira; HEDENSTIERNA, Goeran; LARSSON, Anders; BORGES, Joao BatistaObjective: It is known that ventilator-induced lung injury causes increased pulmonary inflammation. It has been suggested that one of the underlying mechanisms may be strain. The aim of this study was to investigate whether lung regional strain correlates with regional inflammation in a porcine model of acute respiratory distress syndrome. Design: Retrospective analysis of CT images and positron emission tomography images using [F-18]fluoro-2-deoxy-D-glucose. Setting: University animal research laboratory. Subjects: Seven piglets subjected to experimental acute respiratory distress syndrome and five ventilated controls. Interventions: Acute respiratory distress syndrome was induced by repeated lung lavages, followed by 210 minutes of injurious mechanical ventilation using low positive end-expiratory pressures (mean, 4cm H2O) and high inspiratory pressures (mean plateau pressure, 45cm H2O). All animals were subsequently studied with CT scans acquired at end-expiration and end-inspiration, to obtain maps of volumetric strain (inspiratory volume - expiratory volume)/expiratory volume, and dynamic positron emission tomography imaging. Strain maps and positron emission tomography images were divided into 10 isogravitational horizontal regions-of-interest, from which spatial correlation was calculated for each animal. Measurements and Main Results: The acute respiratory distress syndrome model resulted in a decrease in respiratory system compliance (20.33.4 to 14.0 +/- 4.9mL/cm H2O; p < 0.05) and oxygenation (Pao(2)/Fio(2), 489 +/- 80 to 92 +/- 59; p < 0.05), whereas the control animals did not exhibit changes. In the acute respiratory distress syndrome group, strain maps showed a heterogeneous distribution with a greater concentration in the intermediate gravitational regions, which was similar to the distribution of [F-18]fluoro-2-deoxy-D-glucose uptake observed in the positron emission tomography images, resulting in a positive spatial correlation between both variables (median R-2 = 0.71 [0.02-0.84]; p < 0.05 in five of seven animals), which was not observed in the control animals. Conclusion: In this porcine acute respiratory distress syndrome model, regional lung strain was spatially correlated with regional inflammation, supporting that strain is a relevant and prominent determinant of ventilator-induced lung injury.
- 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.
- Early Inflammation Mainly Affects Normally and Poorly Aerated Lung in Experimental Ventilator-Induced Lung Injury*(2014) BORGES, Joao Batista; COSTA, Eduardo L. V.; SUAREZ-SIPMANN, Fernando; WIDSTROM, Charles; LARSSON, Anders; AMATO, Marcelo; HEDENSTIERNA, GoranObjective: The common denominator in most forms of ventilator-induced lung injury is an intense inflammatory response mediated by neutrophils. PET with [F-18]fluoro-2-deoxy-d-glucose can be used to image cellular metabolism, which, during lung inflammatory processes, mainly reflects neutrophil activity, allowing the study of regional lung inflammation in vivo. The aim of this study was to assess the location and magnitude of lung inflammation using PET imaging of [F-18]fluoro-2-deoxy-d-glucose in a porcine experimental model of early acute respiratory distress syndrome. Design: Prospective laboratory investigation. Setting: A university animal research laboratory. Subjects: Seven piglets submitted to experimental ventilator-induced lung injury and five healthy controls. Interventions: Lung injury was induced by lung lavages and 210 minutes of injurious mechanical ventilation using low positive end-expiratory pressure and high inspiratory pressures. All animals were subsequently studied with dynamic PET imaging of [F-18]fluoro-2-deoxy-d-glucose. CT scans were acquired at end expiration and end inspiration. Measurements and Main Results: [F-18]fluoro-2-deoxy-d-glucose uptake rate was computed for the whole lung, four isogravitational regions, and regions grouping voxels with similar density. Global and intermediate gravitational zones [F-18]fluoro-2-deoxy-d-glucose uptakes were higher in ventilator-induced lung injury piglets compared with controls animals. Uptake of normally and poorly aerated regions was also higher in ventilator-induced lung injury piglets compared with control piglets, whereas regions suffering tidal recruitment or tidal hyperinflation had [F-18]fluoro-2-deoxy-d-glucose uptakes similar to controls. Conclusions: The present findings suggest that normally and poorly aerated regionscorresponding to intermediate gravitational zonesare the primary targets of the inflammatory process accompanying early experimental ventilator-induced lung injury. This may be attributed to the small volume of the aerated lung, which receives most of ventilation.
- There is no cephalocaudal gradient of computed tomography densities or lung behavior in supine patients with acute respiratory distress syndrome(2016) EL-DASH, S. A.; BORGES, J. B.; COSTA, E. L. V.; TUCCI, M. R.; RANZANI, O. T.; CARAMEZ, M. P.; CARVALHO, C. R. R.; AMATO, M. B. P.Background: There is debate whether pressure transmission within the lungs and alveolar collapse follow a hydrostatic pattern or the compression exerted by the weight of the heart and the diaphragm causes collapse localized in the areas adjacent to these structures. The second hypothesis proposes the existence of a cephalocaudal gradient in alveolar collapse. We aimed to define whether or not lung density and collapse follow a 'liquid-like' pattern with homogeneous isogravitational layers along the cephalocaudal axis in acute respiratory distress syndrome lungs. Methods: Acute respiratory distress syndrome patients were submitted to full lung computed tomography scans at positive end-expiratory pressure (PEEP) zero (before) and 25 cmH(2)O after a maximum-recruitment maneuver. PEEP was then decreased by 2 cmH2O every 4 min, and a semi-complete scan performed at the end of each PEEP step. Results: Lung densities were homogeneous within each lung layer. Lung density increased along the ventrodorsal axis toward the dorsal region (beta = 0.49, P < 0.001), while there was no increase, but rather a slight decrease, toward the diaphragm along the cephalocaudal axis and toward the heart. Higher PEEP attenuated density gradients. At PEEP 18 cmH2O, dependent lung regions started to collapse massively, while best compliance was only reached at a lower PEEP. Conclusions: We could not detect cephalocaudal gradients in lung densities or in alveolar collapse. Likely, external pressures applied on the lung by the chest wall, organs, and effusions are transmitted throughout the lung in a hydrostatic pattern with homogeneous consequences at each isogravitational layer. A single cross-sectional image of the lung could fully represent the heterogeneous mechanical properties of dependent and non-dependent lung regions.
bookPart SARA: fisiopatologia e estratégia ventilatória(2016) BORGES, João Batista; AMATO, Marcelo; VICTORINO, Josué- The Increasing Call for Protective Ventilation During Anesthesia(2017) BORGES, Joao Batista; AMATO, Marcelo B. P.; HEDENSTIERNA, Goran
- Comment on Borges et al. ""Regional lung perfusion estimated by electrical impedance tomography in a piglet model of lung collapse"" Reply(2012) BORGES, Joao Batista; SUAREZ-SIPMANN, Fernando; COSTA, Eduardo L. V.; HEDENSTIERNA, Goran; AMATO, Marcelo