8 research outputs found
Hemodynamic effects of partial liquid ventilation with perfluorocarbon in acute lung injury
Objective: To assess the effect of partial liquid ventilation with perfluorocarbons on hemodynamics and gas exchange in large pigs with induced acute lung injury (ALI). Design: Randomized, prospective, double-control, experimental study. Setting: Experimental intensive care unit of a university. Materials: Eighteen large pigs (50±5 kg body weight) with an average anterior posterior thoracic diameter of 24 cm and induced acute lung injury. Interventions: All animals were surfactant depleted by lung lavage to a PaO2 below 100 mmHg and randomized to receive either perflubron (n=6) or saline (n=6) in five intratracheal doses of 5 ml/kg at 20-min intervals, or no instillation (n=6). Measurements and results: In all animals heart rate, arterial pressures, pulmonary pressures, cardiac output and blood gases were recorded at 20-min intervals. There was no deleterious effect on any hemodynamic parameter in the perflubron group, whereas systolic and mean pulmonary arterial pressure values showed a persistent decrease after the first 5 ml/kg of perflubron, from 48.7±14.1 to 40.8±11.7 mmHg and from 39.7±13.2 to 35.2±12.0 mmHg, respectively. Perflubron resulted in a significant (ANOVA P<0.01), dose-dependent increase in PaO2 values from 86.3±22.4 to a maximum of 342.4±59.4 mmHg at a dose of 25 ml/kg; the other groups showed no significant increase in PaO2. Conclusions: Tracheal instillation of perflubron in induced ALI results in a dose-dependent increase in PaO2 and has no deleterious effect on hemodynamic parameters
Partial liquid ventilation improves lung function in ventilation-induced lung injury
Disturbances in lung function and lung mechanics are present after
ventilation with high peak inspiratory pressures (PIP) and low levels of
positive end-expiratory pressure (PEEP). Therefore, the authors
investigated whether partial liquid ventilation can re-establish lung
function after ventilation-induced lung injury. Adult rats were exposed to
high PIP without PEEP for 20 min. Thereafter, the animals were randomly
divided into five groups. The first group was killed immediately after
randomization and used as an untreated control. The second group received
only sham treatment and ventilation, and three groups received treatment
with perfluorocarbon (10 mL x kg(-1), 20 mL x kg(-1), and 20 ml x kg(-1)
plus an additional 5 mL x kg(-1) after 1 h). The four groups were
maintained on mechanical ventilation for a further 2-h observation period.
Blood gases, lung mechanics, total protein concentration, minimal surface
tension, and small/large surfactant aggregates ratio were determined. The
results show that in ventilation-induced lung injury, partial liquid
ventilation with different amounts of perflubron improves gas exchange and
pulmonary function, when compared to a group of animals treated with
standard respiratory care. These effects have been observed despite the
presence of a high intra-alveolar protein concentration, especially in
those groups treated with 10 and 20 mL of perflubron. The data suggest
that replacement of perfluorocarbon, lost over time, is crucial to
maintain the constant effects of partial liquid ventilation
Liquid lung ventilation as an alternative ventilatory support
The concept of liquid ventilation has evolved in recent years into the concept of partial liquid ventilation. In this technique, conventional mechanical ventilation is combined with intratracheal perfluorocarbon administration. Partial liquid ventilation is a promising technique for improving gas exchange during mechanical ventilation in neonatal and acute respiratory distress syndrome. The initial data showed no adverse effects on the cardiovascular system, and histological studies demonstrated that perfluorocarbons minimize or prevent the progress of lung injury in animals. Partial liquid ventilation is currently in use in human trials, and in this review we describe the principles of the technique and recently available data of its application
Surfactant impairment after mechanical ventilation with large alveolar surface area changes and effects of positive end-expiratory pressure
We have assessed the effects of overinflation on surfactant function and
composition in rats undergoing ventilation for 20 min with 100% oxygen at
a peak inspiratory pressure of 45 cm H2O, with or without PEEP 10 cm H2O
(groups 45/10 and 45/0, respectively). Mean tidal volumes were 48.4 (SEM
0.3) ml kg-1 in group 45/0 and 18.3 (0.1) ml kg-1 in group 45/10. Arterial
oxygenation in group 45/0 was reduced after 20 min compared with group
45/10 (305 (71) vs 564 (10) mm Hg); maximal compliance of the P-V curve
was decreased (2.09 (0.13) vs 4.16 (0.35) ml cm H2O-1 kg-1); total lung
volume at a transpulmonary pressure of 5 cm H2O was reduced (6.5 (1.0) vs
18.8 (1.4) ml kg-1) and the Gruenwald index was less (0.22 (0.02) vs 0.40
(0.05)). Bronchoalveolar lavage fluid from the group of animals who
underwent ventilation without PEEP had a greater protein concentration
(2.18 (0.11) vs 0.76 (0.22) mg ml-1) and a greater minimal surface tension
(37.2 (6.3) vs 24.5 (2.8) mN m-1) than in those who underwent ventilation
with PEEP. Group 45/0 had an increase in non-active to active total
phosphorus compared with nonventilated controls (0.90 (0.16) vs 0.30
(0.07)). We conclude that ventilation in healthy rats with peak
inspiratory pressures of 45 cm H2O without PEEP for 20 min caused severe
impairment of pulmonary surfactant composition and function which can be
prevented by the use of PEEP 10 cm H2O
Comparison of exogenous surfactant therapy, mechanical ventilation with high end-expiratory pressure and partial liquid ventilation in a model of acute lung injury
We have compared three treatment strategies, that aim to prevent
repetitive alveolar collapse, for their effect on gas exchange, lung
mechanics, lung injury, protein transfer into the alveoli and surfactant
system, in a model of acute lung injury. In adult rats, the lungs were
ventilated mechanically with 100% oxygen and a PEEP of 6 cm H2O, and acute
lung injury was induced by repeated lung lavage to obtain a PaO2 value <
13 kPa. Animals were then allocated randomly (n = 12 in each group) to
receive exogenous surfactant therapy, ventilation with high PEEP (18 cm
H2O), partial liquid ventilation or ventilation with low PEEP (8 cm H2O)
(ventilated controls). Blood-gas values were measured hourly. At the end
of the 4-h study, in six animals per group, pressure-volume curves were
constructed and bronchoalveolar lavage (BAL) was performed, whereas in the
remaining animals lung injury was assessed. In the ventilated control
group, arterial oxygenation did not improve and protein concentration of
BAL and conversion of active to non-active surfactant components increased
significantly. In the three treatment groups, PaO2 increased rapidly to >
50 kPa and remained stable over the next 4 h. The protein concentration of
BAL fluid increased significantly only in the partial liquid ventilation
group. Conversion of active to non-active surfactant components increased
significantly in the partial liquid ventilation group and in the group
venti
Results of Implementing an Enhanced Recovery After Bariatric Surgery (ERABS) Protocol
Background: With the increasing prevalence of morbid obesity and healthcare costs in general, interest is shown in safe, efficient, and cost-effective bariatric care. This study describes an Enhanced Recovery After Bariatric Surgery (ERABS) protocol and the results of implementing such protocol on procedural times, length of stay in hospital (LOS), and the number of complications, such as readmissions and reoperations. Methods: Results of implementing an ERABS protocol were analyzed by comparing a cohort treated according to the ERABS protocol (2012–2014) with a cohort treated before implementing ERABS (2010–2012). Differences between both cohorts were analyzed using independent t tests and chi-squared tests. Results: A total of 1.967 patients (mean age 43.3 years, 80 % female) underwent a primary bariatric procedure between 2010 and 2014, of which 1.313 procedures were performed after implementation of ERABS. A significant decrease of procedural times and a significantly decreased LOS, from 3.2 to 2.0 nights (p < 0.001), were seen after implementation of ERABS. Significantly more complications were seen post-ERABS (16.1 vs. 20.7 %, p = 0.013), although no significant differences were seen in the number of major complications. Conclusion: Implementation of ERABS can result in shorter procedural times and a decreased LOS, which may lead to more efficient and cost-effective bariatric care. The increase in complications was possibly due to better registration of complications. The main goal of an ERABS protocol is efficient, safe, and evidence-based bariatric care, which can be achieved by standardization of the total process