RT Journal Article
SR Electronic
T1 Evaluation of Recruited Lung Volume at Inspiratory Plateau Pressure With PEEP Using Bedside Digital Chest X-ray in Patients With Acute Lung Injury/ARDS
JF Respiratory Care
FD American Association for Respiratory Care
SP 416
OP 423
DO 10.4187/respcare.01893
VO 58
IS 3
A1 Florent Wallet
A1 Bertrand Delannoy
A1 Audrey Haquin
A1 Sophie Debord
A1 Véronique Leray
A1 Gaël Bourdin
A1 Frédérique Bayle
A1 Jean-Christophe Richard
A1 Loic Boussel
A1 Claude Guérin
YR 2013
UL http://rc.rcjournal.com/content/58/3/416.abstract
AB BACKGROUND: We wanted to assess whether there was a significant relationship between recruited lung volume (Vrec) and change in density on digital processed chest x-ray measured at 2 different levels of inspiratory plateau pressure corresponding to 2 PEEP levels in patients with acute lung injury or ARDS. METHODS: In 14 subjects, PEEP 5 cm H2O and 15 cm H2O were prospectively applied in a random order for 10 min. At the end of each period, chest x-ray was taken using a digital portable device, and a pressure-volume curve of the respiratory system was performed. We also assessed PaO2, and the static and the dynamic (Cdyn,rs) compliance of the respiratory system. Change in end-expiratory lung volume between tidal breath and relaxation volume of the respiratory system was determined. Radiological attenuation was measured on chest x-rays in 4 regions of interest in the right lung, and in 3 regions of interest in the left lung, drawn in posterior intercostal spaces from top to bottom, by using dedicated software. The ratio of lung density in each region between PEEP 15 and PEEP 5 (rP15/P5) and their arithmetic mean (μP15/P5) were computed. Vrec was determined from the pressure-volume curves. RESULTS: The median value of rP15/P5 in the 98 lung levels was 0.91 (0.80–1.01), which was significantly different from 1 (P < .001). The values of rP15/P5 were not significantly different between the lung levels. The median values of Vrec and μP15/P5 were 288 (173–402) mL and 0.90 (0.80–0.97), respectively. There was a significant negative correlation between Vrec and μP15/P5 (R = −0.77, P = .01). The reduction in μP15/P5 tended to correlate with the increase in Cdyn,rs (R = −0.49, P = .077) or in PaO2 (R = −0.53, P = .05) between PEEP 15 cm H2O and PEEP 5 cm H2O. CONCLUSIONS: Digital chest x-ray done at the bedside in acute lung injury/ARDS subjects was able to detect a reduction in density between PEEP 5 cm H2O and PEEP 15 cm H2O, which correlated with Vrec.