Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2014 Nov 24;9(11):e113473.
doi: 10.1371/journal.pone.0113473. eCollection 2014.

Sustained inflation at birth did not alter lung injury from mechanical ventilation in surfactant-treated fetal lambs

Noah H Hillman  1 , Matthew W Kemp  2 , Yuichiro Miura  2 , Suhas G Kallapur  3 , Alan H Jobe  3
Affiliations

Sustained inflation at birth did not alter lung injury from mechanical ventilation in surfactant-treated fetal lambs

Noah H Hillman et al. PLoS One. .

Abstract

Background: Sustained inflations (SI) are used with the initiation of ventilation at birth to rapidly recruit functional residual capacity and may decrease lung injury and the need for mechanical ventilation in preterm infants. However, a 20 second SI in surfactant-deficient preterm lambs caused an acute phase injury response without decreasing lung injury from subsequent mechanical ventilation.

Hypothesis: A 20 second SI at birth will decrease lung injury from mechanical ventilation in surfactant-treated preterm fetal lambs.

Methods: The head and chest of fetal sheep at 126±1 day GA were exteriorized, with tracheostomy and removal of fetal lung fluid prior to treatment with surfactant (300 mg in 15 ml saline). Fetal lambs were randomized to one of four 15 minute interventions: 1) PEEP 8 cmH2O; 2) 20 sec SI at 40 cmH2O, then PEEP 8 cmH2O; 3) mechanical ventilation with 7 ml/kg tidal volume; or 4) 20 sec SI then mechanical ventilation at 7 ml/kg. Fetal lambs remained on placental support for the intervention and for 30 min after the intervention.

Results: SI recruited a mean volume of 6.8±0.8 mL/kg. SI did not alter respiratory physiology during mechanical ventilation. Heat shock protein (HSP) 70, HSP60, and total protein in lung fluid similarly increased in both ventilation groups. Modest pro-inflammatory cytokine and acute phase responses, with or without SI, were similar with ventilation. SI alone did not increase markers of injury.

Conclusion: In surfactant treated fetal lambs, a 20 sec SI did not alter ventilation physiology or markers of lung injury from mechanical ventilation.

PubMed Disclaimer

Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist. Suhas Kallapur is a PLOS ONE Editorial Board member. This does not alter the authors' adherence to PLOS ONE Editorial policies and criteria.

Figures

Figure 1
Figure 1. Pro-inflammatory cytokine and acute phase mRNA responses in the lung.
(A) IL-1β did not increase with VT (p>0.05). (B, C) IL-6 and IL-8 mRNA increased similarly for the VT and VT+SI groups, with no increase with SI relative to PEEP alone. (D, E) The acute phase genes Egr-1 and Cyr61 also increased with VT and VT+SI, with no increases with SI relative to PEEP alone. (F) CTGF mRNA did not change. *p<0.05 vs PEEP only.
See this image and copyright information in PMC

References

    1. Hooper SB, Kitchen MJ, Wallace MJ, Yagi N, Uesugi K, et al. (2007) Imaging lung aeration and lung liquid clearance at birth. Faseb J 21:3329–3337. - PubMed
    1. Vyas H, Milner AD, Hopkins IE (1981) Intrathoracic pressure and volume changes during the spontaneous onset of respiration in babies born by cesarean section and by vaginal delivery. J Pediatr 99:787–791. - PubMed
    1. Klingenberg C, Sobotka KS, Ong T, Allison BJ, Schmolzer GM, et al. (2013) Effect of sustained inflation duration; resuscitation of near-term asphyxiated lambs. Arch Dis Child Fetal Neonatal Ed 98:F222–227. - PubMed
    1. Lista G, Fontana P, Castoldi F, Cavigioli F, Dani C (2011) Does sustained lung inflation at birth improve outcome of preterm infants at risk for respiratory distress syndrome? Neonatology 99:45–50. - PubMed
    1. Schilleman K, van der Pot CJ, Hooper SB, Lopriore E, Walther FJ, et al. (2013) Evaluating manual inflations and breathing during mask ventilation in preterm infants at birth. J Pediatr 162:457–463. - PubMed

Publication types

MeSH terms