Regional distribution of acoustic-based lung vibration as a function of mechanical ventilation mode
R Phillip Dellinger, Smith Jean, Ismail Cinel, Christina Tay, Susmita Rajanala, Yael A Glickman, Joseph E Parrillo, R Phillip Dellinger, Smith Jean, Ismail Cinel, Christina Tay, Susmita Rajanala, Yael A Glickman, Joseph E Parrillo
Abstract
Introduction: There are several ventilator modes that are used for maintenance mechanical ventilation but no conclusive evidence that one mode of ventilation is better than another. Vibration response imaging is a novel bedside imaging technique that displays vibration energy of lung sounds generated during the respiratory cycle as a real-time structural and functional image of the respiration process. In this study, we objectively evaluated the differences in regional lung vibration during different modes of mechanical ventilation by means of this new technology.
Methods: Vibration response imaging was performed on 38 patients on assist volume control, assist pressure control, and pressure support modes of mechanical ventilation with constant tidal volumes. Images and vibration intensities of three lung regions at maximal inspiration were analyzed.
Results: There was a significant increase in overall geographical area (p < 0.001) and vibration intensity (p < 0.02) in pressure control and pressure support (greatest in pressure support), compared to volume control, when each patient served as his or her own control while targeting the same tidal volume in each mode. This increase in geographical area and vibration intensity occurred primarily in the lower lung regions. The relative percentage increases were 28.5% from volume control to pressure support and 18.8% from volume control to pressure control (p < 0.05). Concomitantly, the areas of the image in the middle lung regions decreased by 3.6% from volume control to pressure support and by 3.7% from volume control to pressure control (p < 0.05). In addition, analysis of regional vibration intensity showed a 35.5% relative percentage increase in the lower region with pressure support versus volume control (p < 0.05).
Conclusion: Pressure support and (to a lesser extent) pressure control modes cause a shift of vibration toward lower lung regions compared to volume control when tidal volumes are held constant. Better patient synchronization with the ventilator, greater downward movement of the diaphragm, and decelerating flow waveform are potential physiologic explanations for the redistribution of vibration energy to lower lung regions in pressure-targeted modes of mechanical ventilation.
Figures
References
- Gluck E, Sarrigianidis A, Dellinger RP. Mechanical ventilation. In: Parrillo JE, Dellinger RP, editor. Critical Care Medicine: Principles of Diagnosis and Management in the Adult. 2. St. Louis: Mosby; 2001. pp. 137–161.
- Esteban A, Hanzueto A, Alia I, et al. How is mechanical ventilation employed in the intensive care unit? An international utilization review. Am J Respir Crit Care Med. 2000;161:1450–1458.
- Baker AB, Colliss JE, Cowie RW. Effect of varying inspiratory flow waveform and time in intermittent positive pressure ventilation. Various physiological variables. Br J Anaesth. 1977;49:1221–1234. doi: 10.1093/bja/49.12.1221.
- Campbell RS, Davis BR. Pressure-controlled versus volume-controlled ventilation: does it matter? Respir Care. 2002;47:416–424.
- Chiumello D, Pelosi P, Calvi E. Different modes of assisted ventilation in patients with acute respiratory failure. Eur Respir J. 2002;20:925–933. doi: 10.1183/09031936.02.01552001.
- Kallet RH, Alonos JA, Morabito DJ. The effects of PC vs VC assisted ventilation in acute lung injury and ARDS. Respir Care. 2000;45:1085–1096.
- Mead J, Takishina T, Leith D. Stress distribution in lungs: a model of pulmonary elasticity. J Appl Physiol. 1970;28:596–608.
- Rappaport SH, Shipner R, Yoshihara G. Randomized, prospective trial of pressure-limited versus volume-controlled ventilation in severe respiratory failure. Crit Care Med. 1994;22:22–32.
- Davis K, Branson R, Campbell R, Porembka D. Comparison of volume control and pressure control ventilation: is flow waveform the difference? J Trauma. 1996;41:808–814.
- Bergstresser T, Ofengeim D, Vyshedskiy A, Shane J, Murphy R. Sound transmission in the lung as a function of lung volume. J Appl Physiol. 2002;93:667–674.
- Kompis M, Pasterkamp H, Wodicka GR. Acoustic imaging of the human chest. Chest. 2001;120:1309–1321. doi: 10.1378/chest.120.4.1309.
- Rasanen J, Gavriely N. Response of acoustic transmission to positive airway pressure therapy in experimental lung injury. Intensive Care Med. 2005;31:1434–1441. doi: 10.1007/s00134-005-2745-7.
- Jean S, Dellinger RP, Cinel I, Rajanala S, Kushnir I, Parrillo JE. Increased spatial distribution of airflow in lungs with low-level pressure support ventilation compared to maintenance ventilation [abstract] Crit Care. 2006;10(suppl 1):s14. doi: 10.1186/cc4380.
- Jean S, Rajanala S, Cinel I, Wang Z, Ferchau L, Lofland K, Dellinger RP, Parrillo JE. Distribution of vibration energy among different modes of mechanical ventilation [abstract] Chest. 2006;130:s211.
- ImageJ: image processing and analysis in Java
- Prella M, Feihl F, Domenighetti G. Effects of short-term pressure-controlled ventilation on gas exchange, airway pressures, and gas distribution in patients with acute lung injury/ARDS. Comparison with volume-controlled ventilation. Chest. 2002;122:1382–1388. doi: 10.1378/chest.122.4.1382.
- Tobin MJ, Jubran A, Laghi F. Patient-ventilator interaction. Am J Respir Crit Care Med. 2001;163:1059–1063.
- Hess DR, Thompson BT. Patient-ventilator dyssynchrony during lung protective ventilation: what's a clinician to do? Crit Care Med. 2006;34:231–233. doi: 10.1097/01.CCM.0000196083.45897.E9.
- Putensen C, Hering R, Wrigge H. Controlled versus assisted mechanical ventilation. Curr Opin Crit Care. 2002;8:51–57. doi: 10.1097/00075198-200202000-00009.
- Putensen C, Muders T, Varelmann D, Wrigge H. The impact of spontaneous breathing during mechanical ventilation. Curr Opin Crit Care. 2006;12:13–18.
- Kleinman BS, Frey K, van Drunen M. Motion of the diaphragm in patients with chronic obstructive pulmonary disease while spontaneously breathing versus during positive pressure breathing after anesthesia and neuromuscular blockade. Anesthesiology. 2002;97:298–305. doi: 10.1097/00000542-200208000-00003.
- Jousela I, Tahvanainen J, Nikki P. Diaphragmatic movement using ultrasound during spontaneous breathing and mechanical ventilation: effect of tidal volume. Acta Anaesthesiol Belg. 1992;43:165–171.
- Reber A, Nylund U, Hedenstierna G. Position and shape of the diaphragm: implications for atelectasis formation. Anaesthesia. 1998;53:1054–1061. doi: 10.1046/j.1365-2044.1998.00569.x.
- Neumann P, Wrigge H, Zinserling J, Hinz J, Maripuu E, Andersson LG, Putensen C, Hadenstierna G. Spontaneous breathing affects the spatial ventilation and perfusion distribution during mechanical ventilatory support. Crit Care Med. 2005;33:1090–1095. doi: 10.1097/01.CCM.0000163226.34868.0A.
- Wrigge H, Zinserling J, Neuman P. Spontaneous breathing improves lung aeration in oleic acid-induced lung injury. Anesthesiology. 2003;99:376–384. doi: 10.1097/00000542-200308000-00019.
Source: PubMed