Advanced

Quantitative imaging of alveolar recruitment with hyperpolarized gas MRI during mechanical ventilation

Cereda, Maurizio; Emami, Kiarash; Kadlecek, Stephen; Xin, Yi; Mongkolwisetwara, Puttisarn; Profka, Harrilla; Barulic, Amy; Pickup, Stephen; Månsson, Sven LU and Wollmer, Per LU , et al. (2011) In Journal of Applied Physiology 110(2). p.499-511
Abstract
The aim of this study was to assess the utility of He-3 MRI to noninvasively probe the effects of positive end-expiratory pressure (PEEP) maneuvers on alveolar recruitment and atelectasis buildup in mechanically ventilated animals. Sprague-Dawley rats (n = 13) were anesthetized, intubated, and ventilated in the supine position (He-4-to-O-2 ratio: 4:1; tidal volume: 10 ml/kg, 60 breaths/min, and inspiration-to-expiration ratio: 1:2). Recruitment maneuvers consisted of either a stepwise increase of PEEP to 9 cmH(2)O and back to zero end-expiratory pressure or alternating between these two PEEP levels. Diffusion MRI was performed to image He-3 apparent diffusion coefficient (ADC) maps in the middle coronal slices of lungs (n = 10). ADC was... (More)
The aim of this study was to assess the utility of He-3 MRI to noninvasively probe the effects of positive end-expiratory pressure (PEEP) maneuvers on alveolar recruitment and atelectasis buildup in mechanically ventilated animals. Sprague-Dawley rats (n = 13) were anesthetized, intubated, and ventilated in the supine position (He-4-to-O-2 ratio: 4:1; tidal volume: 10 ml/kg, 60 breaths/min, and inspiration-to-expiration ratio: 1:2). Recruitment maneuvers consisted of either a stepwise increase of PEEP to 9 cmH(2)O and back to zero end-expiratory pressure or alternating between these two PEEP levels. Diffusion MRI was performed to image He-3 apparent diffusion coefficient (ADC) maps in the middle coronal slices of lungs (n = 10). ADC was measured immediately before and after two recruitment maneuvers, which were separated from each other with a wait period (8-44 min). We detected a statistically significant decrease in mean ADC after each recruitment maneuver. The relative ADC change was -21.2 +/- 4.1 % after the first maneuver and -9.7 +/- 5.8 % after the second maneuver. A significant relative increase in mean ADC was observed over the wait period between the two recruitment maneuvers. The extent of this ADC buildup was time dependent, as it was significantly related to the duration of the wait period. The two postrecruitment ADC measurements were similar, suggesting that the lungs returned to the same state after the recruitment maneuvers were applied. No significant intrasubject differences in ADC were observed between the corresponding PEEP levels in two rats that underwent three repeat maneuvers. Airway pressure tracings were recorded in separate rats undergoing one PEEP maneuver (n = 3) and showed a significant relative difference in peak inspiratory pressure between pre- and poststates. These observations support the hypothesis of redistribution of alveolar gas due to recruitment of collapsed alveoli in presence of atelectasis, which was also supported by the decrease in peak inspiratory pressure after recruitment maneuvers. (Less)
Please use this url to cite or link to this publication:
author
, et al. (More)
(Less)
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
atelectasis, ventilator-induced lung injury, respiratory gas, distribution, He-3 diffusion magnetic resonance imaging, apparent, diffusion coefficient
in
Journal of Applied Physiology
volume
110
issue
2
pages
499 - 511
publisher
American Physiological Society
external identifiers
  • wos:000288207100025
  • scopus:79851480820
ISSN
1522-1601
DOI
10.1152/japplphysiol.00841.2010
language
English
LU publication?
yes
id
b886f5bd-27ff-42b9-b0d4-7bab04f33508 (old id 1868382)
date added to LUP
2011-04-04 11:17:17
date last changed
2017-08-13 03:26:53
@article{b886f5bd-27ff-42b9-b0d4-7bab04f33508,
  abstract     = {The aim of this study was to assess the utility of He-3 MRI to noninvasively probe the effects of positive end-expiratory pressure (PEEP) maneuvers on alveolar recruitment and atelectasis buildup in mechanically ventilated animals. Sprague-Dawley rats (n = 13) were anesthetized, intubated, and ventilated in the supine position (He-4-to-O-2 ratio: 4:1; tidal volume: 10 ml/kg, 60 breaths/min, and inspiration-to-expiration ratio: 1:2). Recruitment maneuvers consisted of either a stepwise increase of PEEP to 9 cmH(2)O and back to zero end-expiratory pressure or alternating between these two PEEP levels. Diffusion MRI was performed to image He-3 apparent diffusion coefficient (ADC) maps in the middle coronal slices of lungs (n = 10). ADC was measured immediately before and after two recruitment maneuvers, which were separated from each other with a wait period (8-44 min). We detected a statistically significant decrease in mean ADC after each recruitment maneuver. The relative ADC change was -21.2 +/- 4.1 % after the first maneuver and -9.7 +/- 5.8 % after the second maneuver. A significant relative increase in mean ADC was observed over the wait period between the two recruitment maneuvers. The extent of this ADC buildup was time dependent, as it was significantly related to the duration of the wait period. The two postrecruitment ADC measurements were similar, suggesting that the lungs returned to the same state after the recruitment maneuvers were applied. No significant intrasubject differences in ADC were observed between the corresponding PEEP levels in two rats that underwent three repeat maneuvers. Airway pressure tracings were recorded in separate rats undergoing one PEEP maneuver (n = 3) and showed a significant relative difference in peak inspiratory pressure between pre- and poststates. These observations support the hypothesis of redistribution of alveolar gas due to recruitment of collapsed alveoli in presence of atelectasis, which was also supported by the decrease in peak inspiratory pressure after recruitment maneuvers.},
  author       = {Cereda, Maurizio and Emami, Kiarash and Kadlecek, Stephen and Xin, Yi and Mongkolwisetwara, Puttisarn and Profka, Harrilla and Barulic, Amy and Pickup, Stephen and Månsson, Sven and Wollmer, Per and Ishii, Masaru and Deutschman, Clifford S. and Rizi, Rahim R.},
  issn         = {1522-1601},
  keyword      = {atelectasis,ventilator-induced lung injury,respiratory gas,distribution,He-3 diffusion magnetic resonance imaging,apparent,diffusion coefficient},
  language     = {eng},
  number       = {2},
  pages        = {499--511},
  publisher    = {American Physiological Society},
  series       = {Journal of Applied Physiology},
  title        = {Quantitative imaging of alveolar recruitment with hyperpolarized gas MRI during mechanical ventilation},
  url          = {http://dx.doi.org/10.1152/japplphysiol.00841.2010},
  volume       = {110},
  year         = {2011},
}