Derecruitment Test and Surfactant Therapy in Patients with Acute Lung Injury

Introduction. A recruitment maneuver (RM) may improve gas exchange in acute lung injury (ALI). The aim of our study was to assess the predictive value of a derecruitment test in relation to RM and to evaluate the efficacy of RM combined with surfactant instillation in patients with ALI.Materials and Methods. Thirteen adult mechanically ventilated patients with ALI were enrolled into a prospective pilot study. The patients received protective ventilation and underwent RM followed by a derecruitment test. After a repeat RM, bovine surfactant (surfactant group,n=6) or vehicle only (conventional therapy group,n=7) was instilled endobronchially. We registered respiratory and hemodynamic parameters, including extravascular lung water index (EVLWI).Results. The derecruitment test decreased the oxygenation in 62% of the patients. We found no significant correlation between the responses to the RM and to the derecruitment tests. The baseline EVLWI correlated with changes in SpO2following the derecruitment test. The surfactant did not affect gas exchange and lung mechanics but increased EVLWI at 24 and 32 hrs.Conclusions. Our study demonstrated no predictive value of the derecruitment test regarding the effects of RM. Surfactant instillation was not superior to conventional therapy and might even promote pulmonary edema in ALI.

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Management of Phosgene-Induced Acute Lung Injury (ALI) by Personalized Protective PEEP-ECMO: What Can We Learn from Animal Bioassays?

Journal of Integrative Cardiology Open Access ◽

10.31487/j.jicoa.2019.04.13 ◽

2019 ◽

pp. 1-9

Author(s):

Chunli Yang ◽

Yang Xiaogang ◽

Zhaohui He

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Dead Space ◽

Extravascular Lung Water ◽

Lung Mechanics ◽

Lung Edema ◽

Lung Water ◽

Extravascular Lung Water Index ◽

Water Index ◽

Arterial Blood

Background: Phosgene (carbonyl dichloride) gas is an indispensable chemical intermediate used in numerous industrial processes. Acute lung injury (ALI) caused by accidental inhalation exposure to phosgene is characterized pulmonary edema being phenotypically manifested after an asymptomatic or more precisely phrased “clinical occult” period. Opposite to common clinical practice, protective treatment should be given preference to curative treatment. Treatment initiated already during the asymptomatic phase shortly after exposure requires prognostic endpoints preceding the lung edema for triage and re-triage. Treatment strategies need to be personalized and exposure-dose related. The objective of this post-hoc analysis of published data is to assess prognostic value of ventilation dead-space (Vd/Vt) and extravascular lung water index (EVLWI) to guide treatment by protective PEEP supplemented by venovenous (vv) ECMO. Methods: This paper aims to compare the overarching published framework from systematic toxicological research of phosgene in animal bioassays with the clinical evidence from four accidentally phosgenepoisoned workers admitted to hospital with life-threatening lung edema. Treatment focused on a combination of protective PEEP and ECMO to reverse phosgene-induced deterioration in lung mechanics by personalized mechanical ventilation. Endpoints selected for titration PEEP focused on endpoints indicative of decoupling cardiopulmonary and vascular functions. To better understand any cardiogenic and vascular disturbances, titration endpoints included calculated ventilation dead-space (Vd/Vt), measured extravascular lung water index (EVLWI), arterial blood gases and acid-base status, systemic vascular resistance index (SVRI), and cardiac index (CI). EVLWI and APACHE II criteria guided the course of treatment in adjusting plateau pressure (Pplat), positive end-expiratory pressure (PEEP), and driving pressure (ΔP). Results: Remarkable equivalence of human data and those from controlled inhalation studies with phosgene on rats and dogs was found. The endpoint of choice guiding PEEP ventilation and implementation of ECMO was EVLWI. This maker of lung edema precisely reflects the increased wet lung weights in animals. Conclusions: ECMO-supplemented PEEP not only mitigates hypoxemia at conditions of severe ARDS and it also provides a means to reduce driving and plateau pressures minimizing ventilatorassociated lung injury.

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Changes in breath sound power spectra during experimental oleic acid-induced lung injury in pigs

Journal of Applied Physiology ◽

10.1152/japplphysiol.00651.2013 ◽

2014 ◽

Vol 116 (1) ◽

pp. 61-66 ◽

Cited By ~ 5

Author(s):

Jukka Räsänen ◽

Michael E. Nemergut ◽

Noam Gavriely

Keyword(s):

Acute Lung Injury ◽

Oleic Acid ◽

Gas Exchange ◽

Lung Injury ◽

Power Spectra ◽

Lung Mechanics ◽

Sound Power ◽

Frequency Spectra ◽

Mechanically Ventilated ◽

Breath Sounds

To evaluate the effect of acute lung injury on the frequency spectra of breath sounds, we made serial acoustic recordings from nondependent, midlung and dependent regions of both lungs in ten 35- to 45-kg anesthetized, intubated, and mechanically ventilated pigs during development of acute lung injury induced with intravenous oleic acid in prone or supine position. Oleic acid injections rapidly produced severe derangements in the gas exchange and mechanical properties of the lung, with an average increase in venous admixture from 16 ± 12 to 62 ± 16% ( P < 0.01), and a reduction in dynamic respiratory system compliance from 25 ± 4 to 14 ± 4 ml/cmH2O ( P < 0.01). A concomitant increase in sound power was seen in all lung regions ( P < 0.05), predominantly in frequencies 150–800 Hz. The deterioration in gas exchange and lung mechanics correlated best with concurrent spectral changes in the nondependent lung regions. Acute lung injury increases the power of breath sounds likely secondary to redistribution of ventilation from collapsed to aerated parts of the lung and improved sound transmission in dependent, consolidated areas.

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Sustained improvement of gas exchange and lung mechanics by vaporized perfluorocarbon inhalation in piglet acute lung injury model

The Clinical Respiratory Journal ◽

10.1111/crj.12053 ◽

2013 ◽

Vol 8 (2) ◽

pp. 160-166 ◽

Cited By ~ 11

Author(s):

Xiaoguang Wang ◽

Jianpeng Zhang ◽

Xiaoling Li ◽

Youning Liu ◽

Haibo Yang ◽

...

Keyword(s):

Acute Lung Injury ◽

Gas Exchange ◽

Lung Injury ◽

Lung Mechanics ◽

Sustained Improvement ◽

Injury Model ◽

Lung Injury Model

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Continuous tracheal gas insufflation during partial liquid ventilation in juvenile rabbits with acute lung injury

Journal of Applied Physiology ◽

10.1152/japplphysiol.01121.2003 ◽

2004 ◽

Vol 96 (4) ◽

pp. 1415-1424 ◽

Cited By ~ 10

Author(s):

Guangfa Zhu ◽

Thomas H. Shaffer ◽

Marla R. Wolfson

Keyword(s):

Acute Lung Injury ◽

Gas Exchange ◽

Lung Injury ◽

Combined Treatment ◽

Peak Inspiratory Pressure ◽

Oxygenation Index ◽

Lung Mechanics ◽

Partial Liquid Ventilation ◽

Liquid Ventilation ◽

Tracheal Gas Insufflation

To examine the hypothesis that combined treatment with tracheal gas insufflation (TGI) and partial liquid ventilation (PLV) may improve pulmonary outcome relative to either treatment alone in acute lung injury (ALI), saline lavage lung injury was induced in 24 anesthetized, ventilated juvenile rabbits that were then randomly assigned to receive ( n = 6/group) 1) conventional mechanical ventilation (CMV) alone, 2) continuous TGI at 0.5 l/min, 3) PLV with perfluorochemical liquid, and 4) combined TGI and PLV (TGI + PLV), and subsequently ventilated with minimized pressures and tidal volume (Vt) to keep arterial Po2 (PaO2) >100 Torr and arterial Pco2 (PaCO2) at 45-60 Torr for 4 h. Gas exchange, lung mechanics, myeloperoxidase, IL-8, and histomorphometry [including expansion index (EI)] were assessed. The CMV group showed no improvement in lung mechanics and gas exchange; all treated groups had significant increases in compliance, PaO2, ventilation efficacy index (VEI), and EI, and decreases in PaCO2, oxygenation index, physiological dead space-to-Vt ratio (Vd/Vt), myeloperoxidase, and IL-8, relative to the CMV group. TGI resulted in lower peak inspiratory pressure, Vt, Vd/Vt, and greater VEI vs. PLV group; PLV resulted in greater compliance, PaO2, and EI vs. TGI. TGI + PLV resulted in decreased peak inspiratory pressure, Vt, Vd/Vt, and increased VEI compared with TGI, improved compliance and EI compared with PLV, and a further increase in PaO2 and oxygenation index and a decrease in PaCO2 vs. either treatment alone. These results indicate that combined treatment of TGI and PLV results in improved pulmonary outcome than either treatment alone in this animal model of ALI.

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Endotoxemia increases relative perfusion to dorsal-caudal lung regions

Journal of Applied Physiology ◽

10.1152/jappl.2001.90.4.1508 ◽

2001 ◽

Vol 90 (4) ◽

pp. 1508-1515 ◽

Cited By ~ 7

Author(s):

Anthony J. Gerbino ◽

William A. Altemeier ◽

Carmel Schimmel ◽

Robb W. Glenny

Keyword(s):

Spatial Distribution ◽

Acute Lung Injury ◽

Gas Exchange ◽

Lung Injury ◽

Vascular Response ◽

Regional Ventilation ◽

Fluorescent Microspheres ◽

Mechanically Ventilated ◽

Ventilation And Perfusion ◽

Time Point

Changes in the spatial distribution of perfusion during acute lung injury and their impact on gas exchange are poorly understood. We tested whether endotoxemia caused topographical differences in perfusion and whether these differences caused meaningful changes in regional ventilation-to-perfusion ratios and gas exchange. Regional ventilation and perfusion were measured in anesthetized, mechanically ventilated pigs in the prone position before and during endotoxemia with the use of aerosolized and intravenous fluorescent microspheres. On average, relative perfusion halved in ventral and cranial lung regions, doubled in caudal lung regions, and increased 1.5-fold in dorsal lung regions during endotoxemia. In contrast, there were no topographical differences in perfusion before endotoxemia and no topographical differences in ventilation at any time point. Consequently, endotoxemia increased regional ventilation-to-perfusion ratios in the caudal-to-cranial and dorsal-to-ventral directions, resulting in end-capillary Po 2 values that were significantly lower in dorsal-caudal than ventral-cranial regions. We conclude that there are topographical differences in the pulmonary vascular response to endotoxin that may have important consequences for gas exchange in acute lung injury.

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Comparative Effects of Vaporized Perfluorohexane and Partial Liquid Ventilation in Oleic Acid– induced Lung Injury

Anesthesiology ◽

10.1097/00000542-200602000-00013 ◽

2006 ◽

Vol 104 (2) ◽

pp. 278-289 ◽

Cited By ~ 27

Author(s):

Marcelo Gama de Abreu ◽

André Domingues Quelhas ◽

Peter Spieth ◽

Götz Bräuer ◽

Lilla Knels ◽

...

Keyword(s):

Oleic Acid ◽

Gas Exchange ◽

Lung Injury ◽

Diffuse Alveolar Damage ◽

Lung Mechanics ◽

Partial Liquid Ventilation ◽

Positive End Expiratory Pressure ◽

Liquid Ventilation ◽

Mechanically Ventilated ◽

Residual Capacity

Background It is currently not known whether vaporized perfluorohexane is superior to partial liquid ventilation (PLV) for therapy of acute lung injury. In this study, the authors compared the effects of both therapies in oleic acid-induced lung injury. Methods Lung injury was induced in 30 anesthetized and mechanically ventilated pigs by means of central venous infusion of oleic acid. Animals were assigned to one of the following groups: (1) control or gas ventilation (GV), (2) 2.5% perfluorohexane vapor, (3) 5% perfluorohexane vapor, (4) 10% perfluorohexane vapor, or (5) PLV with perfluorooctane (30 ml/kg). Two hours after randomization, lungs were recruited and positive end-expiratory pressure was adjusted to obtain minimal elastance. Ventilation was continued during 4 additional hours, when animals were killed for lung histologic examination. Results Gas exchange and elastance were comparable among vaporized perfluorohexane, PLV, and GV before the open lung approach was used and improved in a similar fashion in all groups after positive end-expiratory pressure was adjusted to optimal elastance (P < 0.05). A similar behavior was observed in functional residual capacity (FRC) in animals treated with vaporized perfluorohexane and GV. Lung resistance improved after recruitment (P < 0.05), but values were higher in the 10% perfluorohexane and PLV groups as compared with GV (P < 0.05). Interestingly, positive end-expiratory pressure values required to obtain minimal elastance were lower with 5% perfluorohexane than with PLV and GV (P < 0.05). In addition, diffuse alveolar damage was significantly lower in the 5% and 10% perfluorohexane vapor groups as compared with PLV and GV (P < 0.05). Conclusions Although the use of 5% vaporized perfluorohexane permitted the authors to reduce pressures needed to stabilize the lungs and was associated with better histologic findings than were PLV and GV, none of these perfluorocarbon therapies improved gas exchange or lung mechanics as compared with GV.

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Small dose of exogenous surfactant combined with partial liquid ventilation in experimental acute lung injury: effects on gas exchange, haemodynamics, lung mechanics, and lung pathology

British Journal of Anaesthesia ◽

10.1093/bja/87.4.593 ◽

2001 ◽

Vol 87 (4) ◽

pp. 593-601 ◽

Cited By ~ 3

Author(s):

S. Wolf ◽

H. Lohbrunner ◽

T. Busch ◽

A. Sterner‐Kock ◽

M. Deja ◽

...

Keyword(s):

Acute Lung Injury ◽

Gas Exchange ◽

Lung Injury ◽

Small Dose ◽

Lung Mechanics ◽

Exogenous Surfactant ◽

Lung Pathology ◽

Partial Liquid Ventilation ◽

Liquid Ventilation

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Choosing the frequency of deep inflation in mice: balancing recruitment against ventilator-induced lung injury

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00532.2005 ◽

2006 ◽

Vol 291 (4) ◽

pp. L710-L717 ◽

Cited By ~ 47

Author(s):

Gilman B. Allen ◽

Benjamin T. Suratt ◽

Lisa Rinaldi ◽

Joseph M. Petty ◽

Jason H. T. Bates

Keyword(s):

Gas Exchange ◽

Lung Injury ◽

Bronchoalveolar Lavage Fluid ◽

Lavage Fluid ◽

Lung Mechanics ◽

Frequency Range ◽

Control Groups ◽

Mechanically Ventilated ◽

Ventilator Induced Lung Injury ◽

Tissue Elastance

Low tidal volume (Vt) ventilation is protective against ventilator-induced lung injury but can promote development of atelectasis. Periodic deep inflation (DI) can open the lung, but if delivered too frequently may cause damage via repeated overdistention. We therefore examined the effects of varying DI frequency on lung mechanics, gas exchange, and biomarkers of injury in mice. C57BL/6 males were mechanically ventilated with positive end-expiratory pressure (PEEP) of 2 cmH2O for 2 h. One high Vt group received a DI with each breath (HV). Low Vt groups received 2 DIs after each hour of ventilation (LV) or 2 DIs every minute (LVDI). Control groups included a nonventilated surgical sham and a group receiving high Vt with zero PEEP (HVZP). Respiratory impedance was measured every 4 min, from which tissue elastance ( H) and damping ( G) were derived. G and H rose progressively during LV and HVZP, but returned to baseline after hourly DI during LV. During LVDI and HV, G and H remained low and gas exchange was superior to that of LV. Bronchoalveolar lavage fluid protein was elevated in HV and HVZP but was not different between LV and LVDI. Lung tissue IL-6 and IL-1β levels were elevated in HVZP and lower in LVDI compared with LV. We conclude that frequent DI can safely improve gas exchange and lung mechanics and may confer protection from biotrauma. Differences between LVDI and HV suggest that an optimal frequency range of DI exists, within which the benefits of maintaining an open lung outweigh injury incurred from overdistention.

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