Analysis of different levels of positive end-expiratory pressure during lung retrieval for transplantation: an experimental study.

Atelectasis and inadequate oxygenation in lung donors is a common problem during the retrieval of these organs. Nevertheless, the use of high positive end-expiratory pressure (PEEP) is not habitual during procedures of lung retrieval. Twenty-one Sprague-Dawley male consanguineous rats were used in the study. The animals were divided into 3 groups according to the level of PEEP used: low (2 cmH2O), moderate (5 cmH2O), and high (10 cmH2O). Animals were ventilated with a tidal volume of 6 mL/kg. Before lung removal, the lungs were inspected for the presence of atelectasis. When atelectasis was detected, alveolar recruitment maneuvers were performed. Blood gasometric analysis was performed immediately. Finally, the lungs were retrieved, weighed, and submitted to histological analysis. The animals submitted to higher PEEP showed higher levels of oxygenation with the same tidal volumes PO2=262.14 (PEEP 2), 382.4 (PEEP 5), and 477.0 (PEEP 10). The occurrence of atelectasis was rare in animals with a PEEP of 10 cmH2O, which therefore required less frequent recruitment maneuvers (need for recruitment: PEEP 2=100%, PEEP 5 =100%, and PEEP 10=14.3%). There was no change in hemodynamic stability, occurrence of pulmonary edema, or other histological injuries with the use of high PEEP. The use of high PEEP (10 cmH2O) was feasible and probably a beneficial strategy for the prevention of atelectasis and the optimization of oxygenation during lung retrieval. Clinical studies should be performed to confirm this hypothesis.

Analysis of different levels of positive end-expiratory pressure during lung retrieval for transplantation: an experimental study

Atelectasis and inadequate oxygenation in lung donors is a common problem during the retrieval of these organs. Nevertheless, the use of high positive end-expiratory pressure (PEEP) is not habitual during procedures of lung retrieval. Twenty-one Sprague-Dawley male consanguineous rats were used in the study. The animals were divided into 3 groups according to the level of PEEP used: low (2 cmH2O), moderate (5 cmH2O), and high (10 cmH2O). Animals were ventilated with a tidal volume of 6 mL/kg. Before lung removal, the lungs were inspected for the presence of atelectasis. When atelectasis was detected, alveolar recruitment maneuvers were performed. Blood gasometric analysis was performed immediately. Finally, the lungs were retrieved, weighed, and submitted to histological analysis. The animals submitted to higher PEEP showed higher levels of oxygenation with the same tidal volumes PO2=262.14 (PEEP 2), 382.4 (PEEP 5), and 477.0 (PEEP 10). The occurrence of atelectasis was rare in animals with a PEEP of 10 cmH2O, which therefore required less frequent recruitment maneuvers (need for recruitment: PEEP 2=100%, PEEP 5 =100%, and PEEP 10=14.3%). There was no change in hemodynamic stability, occurrence of pulmonary edema, or other histological injuries with the use of high PEEP. The use of high PEEP (10 cmH2O) was feasible and probably a beneficial strategy for the prevention of atelectasis and the optimization of oxygenation during lung retrieval. Clinical studies should be performed to confirm this hypothesis.

Association between type of feeding at discharge from the hospital and nutritional status of very low birth weight preterm infants.

The ideal feeding for premature babies has been the source of extensive debate. The aim of this study was to assess the association between type of feeding at discharge and the nutritional status of very low birth weight infants. This was a retrospective cohort of preterm babies with birth weight ≤1500 g, born between January 2006 and December 2013. The infants were divided into 3 groups according to type of feeding at discharge: exclusive breast milk (group 1), mixed feeding (group 2) and exclusive artificial formula (group 3). Frequencies of each group were calculated, as well as mean Z-score differences in weight, length and head circumference. Six hundred and forty-nine newborns were included. The mean weight of groups 1, 2, and 3 was 1338.7, 1104.0, and 1254.7 g, respectively, and their mean gestational age was 31.9, 30, and 31.2 weeks, respectively. The Z-score differences (means±SD) for groups 1, 2, and 3 were: -0.84±0.68, -1.02±0.75, and -0.86±0.71 for weight, -0.21±1.23, -0.52±1.64 and -0.08±1.34 for head circumference, and -1.10±1.18, -1.54±1.37, and -0.97±1.21 for length. A significant difference was observed between groups 2 and 3 in the adjusted Z-score model for length, with no significant differences in anthropometric measurements for the other comparative analyses. Because of its many advantages, breastfeeding should be stimulated within neonatal units since nutritional status was not influenced by the different types of feeding.