| Enhancement of surfactant effect by a mechanical volume recruitment maneuver depends on the lungs preexisting distension. | |
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MedLine Citation:
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PMID: 9573462 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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'Rescue' surfactant treatment of premature infants with respiratory distress syndrome (RDS) results in two mechanisms: stabilization of alveoli already being ventilated and recruitment of alveoli collapsed before surfactant administration. Mechanical recruitment of alveoli from this collapsed compartment might enhance the immediate effects of surfactant treatment. To test this hypothesis 15 mechanically ventilated young rabbits underwent repeated airway lavage with normal saline at a constant, positive end-expiratory pressure (PEEP) of 3 cm H2O until both the a/A ratio was < 0.12 and a peak inspiratory pressure (PIP) > 20 mbar was needed to keep the tidal volume (VT) at 10 ml/kg. Surfactant (Survanta) was given over 4 min in conjunction with a mechanical volume recruitment maneuver (VRM) which consisted of an increased PIP by 33% of baseline values. The effects of surfactant were assessed using two indices of gas exchange (a/A ratio and PaCO2), four indices of lung function (functional residual capacity, FRC, dynamic lung compliance, Crs, VT and the alveolar portion of VT) and postmortem pressure-volume curves and were compared with two groups of rabbits receiving surfactant alone or no surfactant at all. VRM yielded an increase in Crs by +22% whereas VT increased by +58% suggesting overdistension of terminal airways to some extent. There were no differences between the surfactant and the VRM + surfactant groups for all indices assessed after an observational period of 2 h following surfactant administration. In a previous model using a PEEP of 1 cm H2O [Krause et al., Am J Respir Crit Care Med 1997;156:862-866], significant differences have been disclosed for Crs, VT and FRC. In conclusion, the enhancement of surfactant effect by VRM largely depends on the preexisting distension of the lungs. |
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Authors:
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M F Krause; T Hoehn |
Publication Detail:
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Type: Journal Article |
Journal Detail:
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Title: Biology of the neonate Volume: 73 ISSN: 0006-3126 ISO Abbreviation: Biol. Neonate Publication Date: 1998 |
Date Detail:
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Created Date: 1998-06-11 Completed Date: 1998-06-11 Revised Date: 2004-11-17 |
Medline Journal Info:
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Nlm Unique ID: 0247551 Medline TA: Biol Neonate Country: SWITZERLAND |
Other Details:
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Languages: eng Pagination: 320-9 Citation Subset: IM |
Affiliation:
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Children's Hospital, Albert Ludwigs University, Freiburg, Germany. Krause@kk1200.ukl.uni-freiburg.de |
Export Citation:
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| MeSH Terms | |
Descriptor/Qualifier:
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Animals Biological Products* Female Irrigation Lung / anatomy & histology*, drug effects*, physiology Positive-Pressure Respiration Pulmonary Gas Exchange / drug effects Pulmonary Surfactants / administration & dosage, pharmacology* Rabbits Respiration, Artificial |
| Chemical | |
Reg. No./Substance:
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0/Biological Products; 0/Pulmonary Surfactants; 108778-82-1/beractant |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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