Differential effect of recruitment maneuvres on pulmonary blood flow and oxygenation during HFOV in preterm lambs

Research output: Contribution to journalArticleResearchpeer-review

Abstract

The effects of lung volume recruitment manoeuvres on pulmonary blood flow (PBF) during high-frequency oscillatory ventilation (HFOV) in preterm neonates are unknown. As increased airway pressure adversely affects PBF, we compared the effects of two HFOV recruitment strategies on PBF and oxygenation index (OI). Preterm lambs (128+/-1d gestation; term 150d) were anesthetized and ventilated using HFOV (10Hz, 33 tI) with a mean airway pressure (Pao) of 15cmH2O. Lung volume was recruited by either increasing Pao to 25cmH2O for 1 min, repeated 5 times at 5 min intervals (Sigh group; n=5) or stepwise (5cmH2O) changes in Pao at 5 min intervals incrementing up to 30cmH2O then decrementing back to 15 cmH2O (Ramp group; n=6). Controls (n=5) received constant HFOV at 15cmH2O. PBF progressively decreased (by 45+/-4 ) and OI increased (by 15+/-6 , indicating reduced oxygenation) in controls during HFOV which was similar to the changes observed in the Sigh group of lambs. In the Ramp group, PBF fell (by 54+/-10 ) as airway pressure increased (r(2)=0.99), although the PBF did not increase again as the Pao was subsequently reduced. The OI decreased (by 47+/-9 ) reflecting improved oxygenation at high Pao levels during HFOV in the Ramp group. However, high Pao restored retrograde PBF during diastole in 4 of 6 lambs, indicating the restoration of right-to-left shunting through the ductus arteriosus. Thus, the choice of volume recruitment manoeuvre influences the magnitude of change in OI and PBF that occurs during HFOV. Despite significantly improving OI, the ramp recruitment approach causes sustained changes in PBF. Key words: Preterm, lung volume recruitment, waveform analysis, pulmonary blood flow.
Original languageEnglish
Pages (from-to)603 - 610
Number of pages8
JournalJournal of Applied Physiology
Volume105
Issue number2
Publication statusPublished - 2008

Cite this

@article{92ac70130628468e8d816ce9f9833398,
title = "Differential effect of recruitment maneuvres on pulmonary blood flow and oxygenation during HFOV in preterm lambs",
abstract = "The effects of lung volume recruitment manoeuvres on pulmonary blood flow (PBF) during high-frequency oscillatory ventilation (HFOV) in preterm neonates are unknown. As increased airway pressure adversely affects PBF, we compared the effects of two HFOV recruitment strategies on PBF and oxygenation index (OI). Preterm lambs (128+/-1d gestation; term 150d) were anesthetized and ventilated using HFOV (10Hz, 33 tI) with a mean airway pressure (Pao) of 15cmH2O. Lung volume was recruited by either increasing Pao to 25cmH2O for 1 min, repeated 5 times at 5 min intervals (Sigh group; n=5) or stepwise (5cmH2O) changes in Pao at 5 min intervals incrementing up to 30cmH2O then decrementing back to 15 cmH2O (Ramp group; n=6). Controls (n=5) received constant HFOV at 15cmH2O. PBF progressively decreased (by 45+/-4 ) and OI increased (by 15+/-6 , indicating reduced oxygenation) in controls during HFOV which was similar to the changes observed in the Sigh group of lambs. In the Ramp group, PBF fell (by 54+/-10 ) as airway pressure increased (r(2)=0.99), although the PBF did not increase again as the Pao was subsequently reduced. The OI decreased (by 47+/-9 ) reflecting improved oxygenation at high Pao levels during HFOV in the Ramp group. However, high Pao restored retrograde PBF during diastole in 4 of 6 lambs, indicating the restoration of right-to-left shunting through the ductus arteriosus. Thus, the choice of volume recruitment manoeuvre influences the magnitude of change in OI and PBF that occurs during HFOV. Despite significantly improving OI, the ramp recruitment approach causes sustained changes in PBF. Key words: Preterm, lung volume recruitment, waveform analysis, pulmonary blood flow.",
author = "Polglase, {Graeme R} and Timothy Moss and Ilias Nitsos and Allison, {Beth Joyce} and Pillow, {Jane Jane} and Hooper, {Stuart Brian}",
year = "2008",
language = "English",
volume = "105",
pages = "603 -- 610",
journal = "Journal of Applied Physiology",
issn = "8750-7587",
publisher = "American Physiological Society",
number = "2",

}

Differential effect of recruitment maneuvres on pulmonary blood flow and oxygenation during HFOV in preterm lambs. / Polglase, Graeme R; Moss, Timothy; Nitsos, Ilias; Allison, Beth Joyce; Pillow, Jane Jane; Hooper, Stuart Brian.

In: Journal of Applied Physiology, Vol. 105, No. 2, 2008, p. 603 - 610.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Differential effect of recruitment maneuvres on pulmonary blood flow and oxygenation during HFOV in preterm lambs

AU - Polglase, Graeme R

AU - Moss, Timothy

AU - Nitsos, Ilias

AU - Allison, Beth Joyce

AU - Pillow, Jane Jane

AU - Hooper, Stuart Brian

PY - 2008

Y1 - 2008

N2 - The effects of lung volume recruitment manoeuvres on pulmonary blood flow (PBF) during high-frequency oscillatory ventilation (HFOV) in preterm neonates are unknown. As increased airway pressure adversely affects PBF, we compared the effects of two HFOV recruitment strategies on PBF and oxygenation index (OI). Preterm lambs (128+/-1d gestation; term 150d) were anesthetized and ventilated using HFOV (10Hz, 33 tI) with a mean airway pressure (Pao) of 15cmH2O. Lung volume was recruited by either increasing Pao to 25cmH2O for 1 min, repeated 5 times at 5 min intervals (Sigh group; n=5) or stepwise (5cmH2O) changes in Pao at 5 min intervals incrementing up to 30cmH2O then decrementing back to 15 cmH2O (Ramp group; n=6). Controls (n=5) received constant HFOV at 15cmH2O. PBF progressively decreased (by 45+/-4 ) and OI increased (by 15+/-6 , indicating reduced oxygenation) in controls during HFOV which was similar to the changes observed in the Sigh group of lambs. In the Ramp group, PBF fell (by 54+/-10 ) as airway pressure increased (r(2)=0.99), although the PBF did not increase again as the Pao was subsequently reduced. The OI decreased (by 47+/-9 ) reflecting improved oxygenation at high Pao levels during HFOV in the Ramp group. However, high Pao restored retrograde PBF during diastole in 4 of 6 lambs, indicating the restoration of right-to-left shunting through the ductus arteriosus. Thus, the choice of volume recruitment manoeuvre influences the magnitude of change in OI and PBF that occurs during HFOV. Despite significantly improving OI, the ramp recruitment approach causes sustained changes in PBF. Key words: Preterm, lung volume recruitment, waveform analysis, pulmonary blood flow.

AB - The effects of lung volume recruitment manoeuvres on pulmonary blood flow (PBF) during high-frequency oscillatory ventilation (HFOV) in preterm neonates are unknown. As increased airway pressure adversely affects PBF, we compared the effects of two HFOV recruitment strategies on PBF and oxygenation index (OI). Preterm lambs (128+/-1d gestation; term 150d) were anesthetized and ventilated using HFOV (10Hz, 33 tI) with a mean airway pressure (Pao) of 15cmH2O. Lung volume was recruited by either increasing Pao to 25cmH2O for 1 min, repeated 5 times at 5 min intervals (Sigh group; n=5) or stepwise (5cmH2O) changes in Pao at 5 min intervals incrementing up to 30cmH2O then decrementing back to 15 cmH2O (Ramp group; n=6). Controls (n=5) received constant HFOV at 15cmH2O. PBF progressively decreased (by 45+/-4 ) and OI increased (by 15+/-6 , indicating reduced oxygenation) in controls during HFOV which was similar to the changes observed in the Sigh group of lambs. In the Ramp group, PBF fell (by 54+/-10 ) as airway pressure increased (r(2)=0.99), although the PBF did not increase again as the Pao was subsequently reduced. The OI decreased (by 47+/-9 ) reflecting improved oxygenation at high Pao levels during HFOV in the Ramp group. However, high Pao restored retrograde PBF during diastole in 4 of 6 lambs, indicating the restoration of right-to-left shunting through the ductus arteriosus. Thus, the choice of volume recruitment manoeuvre influences the magnitude of change in OI and PBF that occurs during HFOV. Despite significantly improving OI, the ramp recruitment approach causes sustained changes in PBF. Key words: Preterm, lung volume recruitment, waveform analysis, pulmonary blood flow.

UR - http://www.ncbi.nlm.nih.gov/pubmed/18535129

M3 - Article

VL - 105

SP - 603

EP - 610

JO - Journal of Applied Physiology

JF - Journal of Applied Physiology

SN - 8750-7587

IS - 2

ER -