Variable Tidal Volumes Improve Lung Protective Ventilation Strategies in Experimental Lung Injury

Spieth, Peter M.; Carvalho, Alysson R.; Pelosi, Paolo; Hoehn, Catharina; Meißner, Christoph; Kasper, Michael; Hübler, Matthias; Neindorff, Matthias von; Dassow, Constanze; Barrenschee, Martina; Uhlig, Stefan; Koch, Thea; Abreu, Marcelo Gama de

doi:10.1164/rccm.200806-975oc

Cited by 138 publications

(151 citation statements)

References 37 publications

Supporting

Mentioning

137

Contrasting

Unclassified

Order By: Relevance

“…5 In animal models of ARDS, variable ventilation strategies are superior to conventional control mode mechanical ventilation (CMV) or CMV with recruitment maneuvers with respect to lung mechanics, gas exchange, surfactant content, and inflammatory mediators with an overall decrease in distending stress. [5][6][7][8][9][10][11][12] In a recent computed tomography (CT) imaging study, we confirmed BVV induced recruitment of both poorly and non-aerated lung regions. 13 In this study, we hypothesized that the recruitment benefit and periodic low V T breaths seen with BVV could result in enhanced resolution of edema fluid in ARDS.…”

supporting

confidence: 76%

Resolution of pulmonary edema with variable mechanical ventilation in a porcine model of acute lung injury

Graham

Gulati

Kha

et al. 2011

Can J Anesth/J Can Anesth

View full text Add to dashboard Cite

Objective Resolution of the acute respiratory distress syndrome (ARDS) requires clearance of pulmonary edema. Biologically variable ventilation (BVV) strategies that improve gas exchange, lung mechanics, and inflammatory mediators in ARDS may be beneficial in this regard. We used quantitative computed tomography (CT), a single indicator thermodilution system (PiCCOÒ) to determine extravascular lung water (EVLW), and the change in edema protein concentration over time to compare edema clearance with BVV vs conventional mechanical ventilation (CMV) in a porcine ARDS model. Methods Sixteen pigs with oleic acid lung injury were randomized to four hours of ventilation with either CMV (n = 8) or BVV (n = 8) at identical low tidal volume and minute ventilation over time. Hemodynamic variables, gas exchange, lung mechanics, and PiCCO derived EVLW were determined hourly. Computed tomography images and edema fluid samples were obtained at baseline lung injury and after four hours of ventilation. Wet and dry lung weights were determined postmortem.Results At four hours with BVV, peak airway pressure was decreased significantly and lung compliance improved compared with CMV (P = 0.003; P \ 0.001, respectively). Hemodynamic variables and gas exchange were not different between groups. Also at four hours, computed tomography revealed an increase in total gas volume (P = 0.001) and a decrease in total lung weight and global lung density (P = 0.005; P = 0.04 respectively) with BVV. These findings were associated with a significant increase in the gas volume of normally aerated lung regions (P \ 0.001) and a decrease in the poorly and non-aerated lung regions (P = 0.001). No change in any CT parameter occurred with CMV. The lung weights derived from computed tomography correlated well with postmortem wet weights (R 2 = 0.79; P \ 0.01). The decrease in PiCCO derived EVLW from injury to four hours did not differ significantly between BVV and CMV. Extravascular lung water showed no correlation with postmortem wet weights and significantly underestimated lung water. Average alveolar fluid clearance rates were positive (1.4%Áhr -1 (3%)) with BVV and negative with CMV (-2.0%Áhr -1 (4%)). Conclusions In a comparison between BVV and CMV, computed tomography evidence suggests that BVV facilitates enhanced clearance and/or redistribution of edema fluid with improved recruitment of atelectatic and poorly aerated lung regions; no such evidence was seen with either single thermodilution measurement of EVLW or edema clearance rates. The results of computed tomography provide further evidence of the benefit of BVV over conventional ventilation in ARDS. RésuméObjectif La re´solution d'un syndrome de de´tresse respiratoire aigue¨(SDRA) ne´cessite l'e´limination de

show abstract

supporting

confidence: 76%

Resolution of pulmonary edema with variable mechanical ventilation in a porcine model of acute lung injury

Graham

Gulati

Kha

et al. 2011

Can J Anesth/J Can Anesth

View full text Add to dashboard Cite

show abstract

Section: The Role Of Variable Ventilation As a Recruitment Maneuversupporting

confidence: 57%

“…Additionally, the redistribution of pulmonary blood fl ow from cranial to caudal and from ventral to dorsal lung zones was higher and diff use alveolar damage less when variable ventilation was associated with the ventilation strategy recommended by the ARDS Network. Such a redistribution pattern of pulmonary perfusion, which is illustrated in Figure 3, is compatible with lung recruit ment [41].Th e phenomenon of stochastic resonance may explain the higher effi ciency of variable ventilation as a recruitment maneuver. In non-linear systems, like the respiratory system, the amplitude of the output can be modulated by the noise in the input.…”

mentioning

confidence: 59%

“…Time series of V T and respiratory rate values during variable mechanical ventilation may show longrange correlations, which are more strictly 'biological' , or simply random (noisy). Both biological and noisy patterns of variable mechanical ventilation have been shown to improve oxygenation and respiratory mechanics, and reduce diff use alveolar damage in experimental ALI/ ARDS [40,41]. Although diff erent mechanisms have been postulated to explain such fi ndings, lung recruitment seems to play a pivotal role.…”

Section: The Role Of Variable Ventilation As a Recruitment Maneuvermentioning

confidence: 99%

See 1 more Smart Citation

New and Conventional Strategies for Lung Recruitment in Acute Respiratory Distress Syndrome

Pelosi¹,

Abreu²,

Rocco³

2010

Intensive Care Medicine

View full text Add to dashboard Cite

This article is one of ten reviews selected from the Yearbook of Intensive Care and Emergency Medicine 2010 (Springer Verlag) and co-published as a series in Critical Care. Other articles in the series can be found online at http://ccforum/series/yearbook. Further information about the Yearbook of Intensive Care and Emergency Medicine is available from http://www.springer.com/series/2855. Pelosi et al. Critical Care 2010, 14:210 http://ccforum.com/content/14/2/210 © Springer-Verlag Berlin Heidelberg 2010. This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifi cally the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfi lm or in any other way, and storage in data banks. Duplication of this publication or parts thereof is permitted only under the provisions of the German Copyright Law of September 9, 1965, in its current version, and permission for use must always be obtained from Springer-Verlag. Violations are liable for prosecution under the German Copyright Law. recruitment maneuvers may also contribute to VILI [11,12], with translocation of pulmonary bacteria [13] and cytokines into the systemic circulation [14]. Furthermore, since recruitment maneuvers increase mean thoracic pressure, they may lead to a reduction in venous return with impairment of cardiac output [15]. R E V I E WVarious factors may infl uence the response to a recruitment maneuver, namely: 1) Th e nature and extent of lung injury, and 2) patient positioning. Nature and extent of lung injuryTh e nature of the underlying injury can aff ect the response to a recruitment maneuver. In direct (pulmonary) lung injury, the primary structure damaged is the alveolar epithelium resulting in alveolar fi lling by edema, fi brin, and neutrophilic aggregates. In indirect (extrapulmonary) lung injury, infl ammatory mediators are released from extrapulmonary foci into the systemic circulation leading to microvessel congestion and interstitial edema with relative sparing of intra-alveolar spaces [16]. Th erefore, recruitment maneuvers should be more eff ective to open atelectatic lung regions in indirect compared to direct lung injury. Based on this hypothesis, Kloot et al. [17] investigated the eff ects of recruitment maneuvers on gas exchange and lung volumes in three experimental models of ALI: Saline lavage or surfactant depletion, oleic acid, and pneumonia, and observed improvement in oxygenation only in ALI induced by surfactant depletion. Riva et al. [18] compared the eff ects of a recruitment maneuver in models of pulmonary and extrapulmonary ALI, induced by intratracheal and intraperitoneal instillation of Escherichia coli lipo polysaccharide, with similar transpulmonary pressures. Th ey found that the recruitment maneuver was more eff ective for opening collapsed alveoli in extrapulmonary compared to pulmonary ALI, improving lung mechanics and oxygenation with limited damage to alveolar epithelium. Using electrical imp...

show abstract

“…However, the CVRs in Vt and Ti were significantly different between PS and NAVA (p<0.005), with NAVA tidal volumes and inspiratory time more variable. As increased variability has previously been associated with improved ventilation/perfusion ratio and improved oxygenation both in animal models [11][12][13] and humans [14], the ability of NAVA in maintaining higher variability in tidal volume compared to PS could be of potential clinical interest and will require further investigation. Moreover, overall, it is hypothesized that greater variability in breathing pattern is a healthier patient condition.…”

Section: Discussionmentioning

confidence: 99%

NAVA enhances tidal volume and diaphragmatic electro-myographic activity matching: a Range90 analysis of supply and demand

Moorhead

Piquilloud²,

Lambermont

et al. 2012

J Clin Monit Comput

View full text Add to dashboard Cite

show abstract

Variable Tidal Volumes Improve Lung Protective Ventilation Strategies in Experimental Lung Injury

Abstract: Noisy ventilation with variable Vt and fixed respiratory frequency improves respiratory function and reduces histological damage compared with standard protective ventilation strategies.

Cited by 138 publications

References 37 publications

Resolution of pulmonary edema with variable mechanical ventilation in a porcine model of acute lung injury

Resolution of pulmonary edema with variable mechanical ventilation in a porcine model of acute lung injury

New and Conventional Strategies for Lung Recruitment in Acute Respiratory Distress Syndrome

NAVA enhances tidal volume and diaphragmatic electro-myographic activity matching: a Range90 analysis of supply and demand

Contact Info

Product

Resources

About