Gianluigi Li Bassi1,2,3,4, Joan Daniel Martí1,2,3, Talitha Comaru5, Eli Aguilera-Xiol1,2,3, Montserrat Rigol1,2,6, George Ntoumenopoulos7, Silvia Terraneo1, Francesca De Rosa1, Mariano Rinaudo1, Laia Fernandez-Barat1,2,3, Denise Battaglini8, Andrea Meli9, Miguel Ferrer1,2,3,4, Paolo Pelosi8, Davide Chiumello9, Antoni Torres10,2,3,4. 1. Hospital Clínic, Thorax Institute, Department of Pulmonary and Critical Care Medicine, Division of Animal Experimentation, Barcelona, Spain. 2. Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain. 3. Centro de Investigación Biomedica En Red- Enfermedades Respiratorias (CIBERES), Barcelona, Spain. 4. University of Barcelona, Barcelona, Spain. 5. Instituto Federal Farroupilha/Campus Santo Ângelo, Santa Maria, Brazil. 6. Hospital Clínic, Thorax Institute, Cardiology Department, Barcelona, Spain. 7. Physiotherapy Department, Guy's & St Thomas' NHS Foundation Trust, United Kingdom, and the Physiotherapy Services Critical Care, St Vincent's Hospital Sydney, Sydney, Australia. 8. Dipartimento Scienze Chirurgiche e Diagnostiche Integrate (DISC), Università degli Studi di Genova, Genova, Italia. 9. Dipartimento di Anestesia e Rianimazione, ASST Santi Paolo e Carlo, Dipartimento di Scienza e Salute - Universita degli Studi di Milano, Milan, Italy. 10. Hospital Clínic, Thorax Institute, Department of Pulmonary and Critical Care Medicine, Division of Animal Experimentation, Barcelona, Spain. atorres@clinic.ub.es.
Abstract
BACKGROUND: In patients on mechanical ventilation, lung hyperinflation is often performed to reverse atelectasis and clear retained mucus. We evaluated the effects of manual hyperinflation and ventilator hyperinflation on mucus clearance, gas exchange, pulmonary mechanics, and hemodynamics. METHODS: Six mechanically ventilated pigs with severe Pseudomonas aeruginosa pneumonia randomly received either 12 manual hyperinflation breaths over a period of 2 min (through a gradual manual compression of a resuscitation bag within 4 s to achieve 40 cm H2O of airway pressure), or 12 ventilator hyperinflation over 2 min to achieve the same ventilatory end points as in manual hyperinflation. Mucus clearance rate was measured through fluoroscopic tracking of tracheal markers. Prior to each maneuver and 15 min thereafter, we assessed arterial and mixed gas exchange, pulmonary mechanics, and hemodynamics. RESULTS: Both manual hyperinflation and ventilator hyperinflation significantly decreased inspiratory flow by approximately 16 L/min (P < .001) and increased peak expiratory flow by roughly 44 L/min (P < .001). The median (interquartile range) mucus clearance rate was 1.31 (0.84-2.30) prior to the interventions, and 0.70 (0.00-2.58) and 0.65 (0.45-1.47) during manual hyperinflation and ventilator hyperinflation, respectively (P = .09). Hyperinflations, whether delivered manually or through the ventilator, did not significantly modify pulmonary or hemodynamic parameters. CONCLUSIONS: In an animal model of severe P. aeruginosa pneumonia, neither manual hyperinflation nor ventilator hyperinflation improved mucus clearance. If confirmed in comprehensive clinical experimentations, these findings should promote reappraisal of indications for both manual hyperinflation and ventilator hyperinflation as a therapeutic technique for mucus clearance and atelectasis reversal.
BACKGROUND: In patients on mechanical ventilation, lung hyperinflation is often performed to reverse atelectasis and clear retained mucus. We evaluated the effects of manual hyperinflation and ventilator hyperinflation on mucus clearance, gas exchange, pulmonary mechanics, and hemodynamics. METHODS: Six mechanically ventilated pigs with severe Pseudomonas aeruginosa pneumonia randomly received either 12 manual hyperinflation breaths over a period of 2 min (through a gradual manual compression of a resuscitation bag within 4 s to achieve 40 cm H2O of airway pressure), or 12 ventilator hyperinflation over 2 min to achieve the same ventilatory end points as in manual hyperinflation. Mucus clearance rate was measured through fluoroscopic tracking of tracheal markers. Prior to each maneuver and 15 min thereafter, we assessed arterial and mixed gas exchange, pulmonary mechanics, and hemodynamics. RESULTS: Both manual hyperinflation and ventilator hyperinflation significantly decreased inspiratory flow by approximately 16 L/min (P < .001) and increased peak expiratory flow by roughly 44 L/min (P < .001). The median (interquartile range) mucus clearance rate was 1.31 (0.84-2.30) prior to the interventions, and 0.70 (0.00-2.58) and 0.65 (0.45-1.47) during manual hyperinflation and ventilator hyperinflation, respectively (P = .09). Hyperinflations, whether delivered manually or through the ventilator, did not significantly modify pulmonary or hemodynamic parameters. CONCLUSIONS: In an animal model of severe P. aeruginosa pneumonia, neither manual hyperinflation nor ventilator hyperinflation improved mucus clearance. If confirmed in comprehensive clinical experimentations, these findings should promote reappraisal of indications for both manual hyperinflation and ventilator hyperinflation as a therapeutic technique for mucus clearance and atelectasis reversal.
Authors: Gary F Nieman; Hassan Al-Khalisy; Michaela Kollisch-Singule; Joshua Satalin; Sarah Blair; Girish Trikha; Penny Andrews; Maria Madden; Louis A Gatto; Nader M Habashi Journal: Front Physiol Date: 2020-03-19 Impact factor: 4.566