TY - JOUR
T1 - Recruitment manoeuvres dislodge mucus towards the distal airways in an experimental model of severe pneumonia
AU - Li Bassi, G.
AU - Comaru, T.
AU - Martí, D.
AU - Xiol, E. A.
AU - Chiurazzi, C.
AU - Travierso, C.
AU - Carbonara, M.
AU - Ranzani, O. T.
AU - Amaro, R.
AU - Frigola, G.
AU - Fuster, C.
AU - Saco, M. A.
AU - Zanella, A.
AU - De Rosa, F.
AU - Rigol, M.
AU - Fernandez, L.
AU - Luque, N.
AU - Ramirez, J.
AU - Blasi, F.
AU - Suen, J.
AU - Fraser, J.
AU - Torres, A.
N1 - Publisher Copyright:
© 2018
PY - 2019/2
Y1 - 2019/2
N2 - Background: Recruitment manoeuvres generate a transient increase in trans-pulmonary pressure that could open collapsed alveoli. Recruitment manoeuvres might generate very high inspiratory airflows. We evaluated whether recruitment manoeuvres could displace respiratory secretions towards the distal airways and impair gas exchange in a porcine model of bacterial pneumonia. Methods: We conducted a prospective randomised study in 10 mechanically ventilated pigs. Pneumonia was produced by direct intra-bronchial introduction of Pseudomonas aeruginosa. Four recruitment manoeuvres were applied randomly: extended sigh (ES), maximal recruitment strategy (MRS), sudden increase in driving pressure and PEEP (SI-PEEP), and sustained inflation (SI). Mucus transport was assessed by fluoroscopic tracking of radiopaque disks before and during each recruitment manoeuvre. The effects of each RM on gas exchange were assessed 15 min after the intervention. Results: Before recruitment manoeuvres, mucus always cleared towards the glottis. Conversely, mucus was displaced towards the distal airways in 28.6% ES applications and 50% of all other recruitment manoeuvres (P=0.053). Median mucus velocity was 1.26 mm min −1 [0.48–3.89] before each recruitment manoeuvre, but was reversed (P=0.007) during ES [0.10 mm min −1 [-0.04–1.00]], MRS [0.10 mm min −1 [-0.4–0.48]], SI-PEEP [0.02 mm min −1 [-0.14–0.34]], and SI [0.10 mm min −1 [-0.63–0.75]]. When PaO 2 failed to improve after recruitment manoeuvre, mucus was displaced towards the distal airways in 68.7% of the cases, compared with 31.2% recruitment manoeuvres associated with improved PaO 2 (odds ratio: 4.76 (95% confidence interval: 1.13–19.97). Conclusions: Recruitment manoeuvres dislodge mucus distally, irrespective of airflow generated by different recruitment manoeuvres. Further investigation in humans is warranted to corroborate these pre clinical findings, as there may be limited benefits associated with lung recruitment in pneumonia.
AB - Background: Recruitment manoeuvres generate a transient increase in trans-pulmonary pressure that could open collapsed alveoli. Recruitment manoeuvres might generate very high inspiratory airflows. We evaluated whether recruitment manoeuvres could displace respiratory secretions towards the distal airways and impair gas exchange in a porcine model of bacterial pneumonia. Methods: We conducted a prospective randomised study in 10 mechanically ventilated pigs. Pneumonia was produced by direct intra-bronchial introduction of Pseudomonas aeruginosa. Four recruitment manoeuvres were applied randomly: extended sigh (ES), maximal recruitment strategy (MRS), sudden increase in driving pressure and PEEP (SI-PEEP), and sustained inflation (SI). Mucus transport was assessed by fluoroscopic tracking of radiopaque disks before and during each recruitment manoeuvre. The effects of each RM on gas exchange were assessed 15 min after the intervention. Results: Before recruitment manoeuvres, mucus always cleared towards the glottis. Conversely, mucus was displaced towards the distal airways in 28.6% ES applications and 50% of all other recruitment manoeuvres (P=0.053). Median mucus velocity was 1.26 mm min −1 [0.48–3.89] before each recruitment manoeuvre, but was reversed (P=0.007) during ES [0.10 mm min −1 [-0.04–1.00]], MRS [0.10 mm min −1 [-0.4–0.48]], SI-PEEP [0.02 mm min −1 [-0.14–0.34]], and SI [0.10 mm min −1 [-0.63–0.75]]. When PaO 2 failed to improve after recruitment manoeuvre, mucus was displaced towards the distal airways in 68.7% of the cases, compared with 31.2% recruitment manoeuvres associated with improved PaO 2 (odds ratio: 4.76 (95% confidence interval: 1.13–19.97). Conclusions: Recruitment manoeuvres dislodge mucus distally, irrespective of airflow generated by different recruitment manoeuvres. Further investigation in humans is warranted to corroborate these pre clinical findings, as there may be limited benefits associated with lung recruitment in pneumonia.
KW - adult respiratory distress syndrome
KW - artificial respiration
KW - mechanical ventilation
KW - mucus
KW - pneumonia
KW - recruitment manoeuvre
UR - http://www.scopus.com/inward/record.url?scp=85056231515&partnerID=8YFLogxK
U2 - 10.1016/j.bja.2018.07.039
DO - 10.1016/j.bja.2018.07.039
M3 - Article
C2 - 30686313
AN - SCOPUS:85056231515
SN - 0007-0912
VL - 122
SP - 269
EP - 276
JO - British Journal of Anaesthesia
JF - British Journal of Anaesthesia
IS - 2
ER -