Effects of exogenous surfactant on lung pressure-volume characteristics during liquid ventilation

1996 ◽  
Vol 80 (5) ◽  
pp. 1764-1771 ◽  
Author(s):  
P. Tarczy-Hornoch ◽  
J. Hildebrandt ◽  
E. A. Mates ◽  
T. A. Standaert ◽  
W. J. Lamm ◽  
...  
Keyword(s):  
Surface Tension ◽  
Interfacial Tension ◽  
Hyaline Membrane Disease ◽  
Exogenous Surfactant ◽  
Liquid Ventilation ◽  
Novel Approach ◽  
Hyaline Membrane ◽  
Volume Characteristics ◽  
Reducing Properties

Total liquid ventilation (LV) lowers airway pressures and potentially reduces barotrauma in models of hyaline membrane disease. LV eliminates surface tension by eliminating the air-perfluorochemicals (PFC) interface but does not eliminate interfacial tension (IT) at the lung/PFC interface. We hypothesized that pretreatment with exogenous surfactant before LV would shift the overall pressure-volume (PV) curve to the left, compared with LV without surfactant. Sequential quasi-static PV curves were obtained in 10 excised lungs (saline, air, PFC), with one-half randomized to exogenous surfactant replacement before LV. Analysis revealed that maximal inflation pressures were reduced during LV compared with baseline air curves. Addition of exogenous surfactant to LV further reduced maximal inflation pressures. A novel approach was used to transform these PV curves to estimates of in situ IT-volume curves. Estimated maximal IT at 20 ml/kg in preterm lamb lungs on air inflation after surfactant was 51 mN/m, compared with 40 mN/m for LV alone and with 27 mN/m for the combination of surfactant and LV. We conclude that the IT-reducing properties of the PFC studied (perflubron) can be augmented through the use of exogenous surfactant.

THE ALVEOLAR LINING LAYER

PEDIATRICS ◽  
1962 ◽  
Vol 30 (2) ◽  
pp. 324-330
Author(s):  
Mary Ellen Avery
Keyword(s):  
Surface Tension ◽  
Secretory Activity ◽  
Hyaline Membrane Disease ◽  
Normal Lung ◽  
Elastic Recoil ◽  
Alveolar Cells ◽  
Electron Microscopic ◽  
Hyaline Membrane ◽  
Surface Active ◽  
Air Liquid Interface

The alveoli of the normal lung are lined by a substance which exerts surface tension at the air-liquid interface. In the expanded lung the tension is high and operates to increase the elastic recoil of the lung. In the lung at low volumes the surface tension becomes extremely low. This confers stability on the airspaces and thus prevents atelectasis. This lining layer is a lipoprotein film, which is not found where alveoli are still lined by cuboidal epithelium. Its time of appearance coincides with the appearance of alveolar lining cells. Electron microscopic evidence of secretory activity in alveolar cells suggests that they may be the source of the surface-active film. The normal alveolar lining layer is not present in lungs of infants who die from profound atelectasis and hyaline membrane disease. Whether its absence is a failure of development or due to inactivation is not established.

Surfactant replacement increases compliance in premature lamb lungs during partial liquid ventilation in situ

1998 ◽  
Vol 84 (4) ◽  
pp. 1316-1322 ◽  
Author(s):  
Peter Tarczy-Hornoch ◽  
Jack Hildebrandt ◽  
Thomas A. Standaert ◽  
J. Craig Jackson
Keyword(s):  
Force Balance ◽  
Exogenous Surfactant ◽  
Partial Liquid Ventilation ◽  
Liquid Ventilation ◽  
Lung Inflation ◽  
Surfactant Replacement ◽  
Improve Compliance ◽  
Alveolar Surface ◽  
Force Balance Equation

Treatments available to improve compliance in surfactant-deficient states include exogenous surfactant (ES) and either partial (PLV) or total liquid ventilation (TLV) with perfluorochemical (PFC). Because of the additional air-lung and air-PFC interfaces introduced during PLV compared with TLV, we hypothesized that compliance would be worse during PLV than during TLV. Because surfactant is able to reduce interfacial tension between air and lung as well as between PFC and lung, we further hypothesized that compliance would improve with surfactant treatment before PLV. In excised preterm lamb lungs, we used Survanta for surfactant replacement and perflubron as the PFC. Compliance during PLV was intermediate between TLV and gas inflation, both with and without surfactant. Surfactant improved compliance during PLV, compared with PLV alone. Because of the force-balance equation governing the behavior of immiscible droplets on liquid surfaces, we predict that PFC droplets spread during PLV to cover the alveolar surface in surfactant-deficient lungs during most of lung inflation and deflation but that the PFC would retract into droplets in surfactant-sufficient lungs, except at end inspiration.

Randomized Controlled Trial of Exogenous Surfactant for the Treatment of Hyaline Membrane Disease

PEDIATRICS ◽  
1987 ◽  
Vol 79 (1) ◽  
pp. 31-37 ◽  
Author(s):  
Jonathan D. Gitlin ◽  
Roger F. Soll ◽  
Richard B. Parad ◽  
Jeffrey D. Horbar ◽  
Henry A. Feldman ◽  
...  
Keyword(s):  
Controlled Trial ◽  
Hyaline Membrane Disease ◽  
Respiratory Support ◽  
Exogenous Surfactant ◽  
Low Birth Weight Infants ◽  
Ventilator Support ◽  
Randomized Controlled ◽  
Acute Side Effects ◽  
Hyaline Membrane ◽  
Inspiratory Oxygen

We conducted a prospective, randomized, unblinded, controlled trial of exogenous bovine surfactant (surfactant TA) in premature infants requiring ventilator support for the treatment of severe hyaline membrane disease. Forty-one low birth weight infants with severe hyaline membrane disease were randomly assigned to saline or surfactant therapy and treated within eight hours of birth. Significant improvements in oxygenation (increased arterial/alveolar Po2) and respiratory support (decreased mean airway pressure) were seen in the group receiving surfactant within four hours after treatment. These improvements were maintained in the surfactant-treated infants, who also had fewer pneumothoraces and fewer number of days in environments of fractional inspiratory oxygen greater than 0.4 mm Hg. No problems were associated with administration of surfactant, and no acute side effects were detected. We conclude that exogenous surfactant, administered early in the course of severe hyaline membrane disease, is an effective therapy that can diminish the amount of respiratory support required during the first 48 hours of life.

scholarly journals Surface tension in situ in flooded alveolus unaltered by albumin

2014 ◽  
Vol 117 (5) ◽  
pp. 440-451 ◽  
Author(s):  
Angana Banerjee Kharge ◽  
You Wu ◽  
Carrie E. Perlman
Keyword(s):  
Surface Tension ◽  
Plasma Proteins ◽  
Lung Surfactant ◽  
Exogenous Surfactant ◽  
Surfactant Activity ◽  
Interfacial Surfactant ◽  
Isolated Rat Lung ◽  
Alveolar Liquid

In the acute respiratory distress syndrome, plasma proteins in alveolar edema liquid are thought to inactivate lung surfactant and raise surface tension, T. However, plasma protein-surfactant interaction has been assessed only in vitro, during unphysiologically large surface area compression (%Δ A). Here, we investigate whether plasma proteins raise T in situ in the isolated rat lung under physiologic conditions. We flood alveoli with liquid that omits/includes plasma proteins. We ventilate the lung between transpulmonary pressures of 5 and 15 cmH2O to apply a near-maximal physiologic %Δ A, comparable to that of severe mechanical ventilation, or between 1 and 30 cmH2O, to apply a supraphysiologic %Δ A. We pause ventilation for 20 min and determine T at the meniscus that is present at the flooded alveolar mouth. We determine alveolar air pressure at the trachea, alveolar liquid phase pressure by servo-nulling pressure measurement, and meniscus radius by confocal microscopy, and we calculate T according to the Laplace relation. Over 60 ventilation cycles, application of maximal physiologic %Δ A to alveoli flooded with 4.6% albumin solution does not alter T; supraphysiologic %Δ A raise T, transiently, by 51 ± 4%. In separate experiments, we find that addition of exogenous surfactant to the alveolar liquid can, with two cycles of maximal physiologic %Δ A, reduce T by 29 ± 11% despite the presence of albumin. We interpret that supraphysiologic %Δ A likely collapses the interfacial surfactant monolayer, allowing albumin to raise T. With maximal physiologic %Δ A, the monolayer likely remains intact such that albumin, blocked from the interface, cannot interfere with native or exogenous surfactant activity.

scholarly journals Treatment of Patent Ductus Arteriosus after Exogenous Surfactant in Baboons with Hyaline Membrane Disease

1989 ◽  
Vol 26 (6) ◽  
pp. 565-566 ◽  
Author(s):  
Senji Shimada ◽  
Tonse N K Raju ◽  
Rama Bhat ◽  
Haruo Maeta ◽  
Dharmapuri Vidyasagar
Keyword(s):  
Patent Ductus Arteriosus ◽  
Ductus Arteriosus ◽  
Hyaline Membrane Disease ◽  
Exogenous Surfactant ◽  
Hyaline Membrane ◽  
Patent Ductus

▾ Colfosceril palmitate (exosurf) – artificial surfactant for immature lungs

1991 ◽  
Vol 29 (12) ◽  
pp. 46.1-46
Keyword(s):  
Surface Tension ◽  
Respiratory Function ◽  
Distress Syndrome ◽  
Hyaline Membrane Disease ◽  
Lower Surface ◽  
Premature Babies ◽  
Hyaline Membrane ◽  
Lower Surface Tension ◽  
Reducing Substances ◽  
Artificial Surfactant

It has been known for about 30 years that lack of surface tension reducing substances (‘surfactant’) in the lungs of premature infants is largely responsible for the development of hyaline membrane disease or respiratory distress syndrome (RDS). About 50% of premature babies develop RDS, characteristically showing tachypnoea, chest retractions and worsening cyanosis. Many babies die of it or suffer complications. Mechanical ventilation is the main treatment, supporting respiratory function until maturing alveolar lining cells synthesise adequate surfactant. Despite its inherent risks it has proved very successful, but drugs which can lower surface tension in the lungs may improve outcome further.

The Body Lymphatics in Neonatal Hyaline Membrane Disease

PEDIATRICS ◽  
1969 ◽  
Vol 44 (1) ◽  
pp. 126-128
Author(s):  
J. M. Lauweryns ◽  
M. Deleersnyder ◽  
L. Boussauw
Keyword(s):  
Surface Tension ◽  
Fetal Lung ◽  
Hyaline Membrane Disease ◽  
The Body ◽  
Hyaline Membrane ◽  
Wall Permeability ◽  
Lung Liquid ◽  
Delayed Removal ◽  
Generalized Distribution

In analyzing the significance of the recently reported increase in diameter of the pulmonary lymphatics in neonatal hyaline membrane disease (HMD), it seems pertinent to examine by identical morphometrical methods and in the same infants the occurrence versus the absence of this same phenomenon in some other body organs. Were this lymphangiectasis—as claimed by Stowens—of a very generalized distribution throughout the body, one would indeed have to consider the significance of its occurrence in the lungs in a more general way, i.e., as not only restricted to a more exclusive pulmonary origin (such as a disturbed alveolocapillary wall permeability, a delayed removal of fetal lung liquid, or higher surface tension characteristics).

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