PaCO2 and alveolar dead space are more relevant than PaO2/FiO2 ratio in monitoring the respiratory response to prone position in ARDS patients: a physiological study
Tóm tắt
Our aims in this study were to report changes in the ratio of alveolar dead space to tidal volume (VDalv/VT) in the prone position (PP) and to test whether changes in partial pressure of arterial CO2 (PaCO2) may be more relevant than changes in the ratio of partial pressure of arterial O2 to fraction of inspired O2 (PaO2/FiO2) in defining the respiratory response to PP. We also aimed to validate a recently proposed method of estimation of the physiological dead space (VDphysiol/VT) without measurement of expired CO2. Thirteen patients with a PaO2/FiO2 ratio < 100 mmHg were included in the study. Plateau pressure (Pplat), positive end-expiratory pressure (PEEP), blood gas analysis and expiratory CO2 were recorded with patients in the supine position and after 3, 6, 9, 12 and 15 hours in the PP. Responders to PP were defined after 15 hours of PP either by an increase in PaO2/FiO2 ratio > 20 mmHg or by a decrease in PaCO2 > 2 mmHg. Estimated and measured VDphysiol/VT ratios were compared. PP induced a decrease in Pplat, PaCO2 and VDalv/VT ratio and increases in PaO2/FiO2 ratios and compliance of the respiratory system (Crs). Maximal changes were observed after six to nine hours. Changes in VDalv/VT were correlated with changes in Crs, but not with changes in PaO2/FiO2 ratios. When the response was defined by PaO2/FiO2 ratio, no significant differences in Pplat, PaCO2 or VDalv/VT alterations between responders (n = 7) and nonresponders (n = 6) were observed. When the response was defined by PaCO2, four patients were differently classified, and responders (n = 7) had a greater decrease in VDalv/VT ratio and in Pplat and a greater increase in PaO2/FiO2 ratio and in Crs than nonresponders (n = 6). Estimated VDphysiol/VT ratios significantly underestimated measured VDphysiol/VT ratios (concordance correlation coefficient 0.19 (interquartile ranges 0.091 to 0.28)), whereas changes during PP were more reliable (concordance correlation coefficient 0.51 (0.32 to 0.66)). PP induced a decrease in VDalv/VT ratio and an improvement in respiratory mechanics. The respiratory response to PP appeared more relevant when PaCO2 rather than the PaO2/FiO2 ratio was used. Estimated VDphysiol/VT ratios systematically underestimated measured VDphysiol/VT ratios.
Tài liệu tham khảo
Ashbaugh DG, Bigelow DB, Petty TL, Levine BE: Acute respiratory distress in adults. Lancet 1967, 2: 319-323.
Gattinoni L, Pesenti A: The concept of "baby lung". Intensive Care Med 2005, 31: 776-784. 10.1007/s00134-005-2627-z
The Acute Respiratory Distress Syndrome Network: Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. N Engl J Med 2000, 342: 1301-1308.
Puybasset L, Gusman P, Muller JC, Cluzel P, Coriat P, Rouby JJ: Regional distribution of gas and tissue in acute respiratory distress syndrome. III. Consequences for the effects of positive end-expiratory pressure. CT Scan ARDS Study Group. Adult Respiratory Distress Syndrome. Intensive Care Med 2000, 26: 1215-1227. 10.1007/s001340051340
Rouby JJ, Brochard L: Tidal recruitment and overinflation in acute respiratory distress syndrome: yin and yang. Am J Respir Crit Care Med 2007, 175: 104-106.
Bryan AC: Conference on the scientific basis of respiratory therapy: pulmonary physiotherapy in the pediatric age group. Comments of a devil's advocate. Am Rev Respir Dis 1974, 110: 143-144.
Douglas WW, Rehder K, Beynen FM, Sessler AD, Marsh HM: Improved oxygenation in patients with acute respiratory failure: the prone position. Am Rev Respir Dis 1977, 115: 559-566.
Sud S, Friedrich JO, Taccone P, Polli F, Adhikari NK, Latini R, Pesenti A, Guérin C, Mancebo J, Curley MA, Fernandez R, Chan MC, Beuret P, Voggenreiter G, Sud M, Tognoni G, Gattinoni L: Prone ventilation reduces mortality in patients with acute respiratory failure and severe hypoxemia: systematic review and meta-analysis. Intensive Care Med 2010, 36: 585-599. 10.1007/s00134-009-1748-1
Chatte G, Sab JM, Dubois JM, Sirodot M, Gaussorgues P, Robert D: Prone position in mechanically ventilated patients with severe acute respiratory failure. Am J Respir Crit Care Med 1997, 155: 473-478.
Gattinoni L, Vagginelli F, Carlesso E, Taccone P, Conte V, Chiumello D, Valenza F, Caironi P, Pesenti A: Decrease in PaCO 2 with prone position is predictive of improved outcome in acute respiratory distress syndrome. Crit Care Med 2003, 31: 2727-2733. 10.1097/01.CCM.0000098032.34052.F9
Jolliet P, Bulpa P, Chevrolet JC: Effects of the prone position on gas exchange and hemodynamics in severe acute respiratory distress syndrome. Crit Care Med 1998, 26: 1977-1985. 10.1097/00003246-199812000-00023
Vieillard-Baron A, Rabiller A, Chergui K, Peyrouset O, Page B, Beauchet A, Jardin F: Prone position improves mechanics and alveolar ventilation in acute respiratory distress syndrome. Intensive Care Med 2005, 31: 220-226. 10.1007/s00134-004-2478-z
Nuckton TJ, Alonso JA, Kallet RH, Daniel BM, Pittet JF, Eisner MD, Matthay MA: Pulmonary dead-space fraction as a risk factor for death in the acute respiratory distress syndrome. N Engl J Med 2002, 346: 1281-1286. 10.1056/NEJMoa012835
Siddiki H, Kojicic M, Yilmaz M, Thompson TB, Humayr RD, Gajic O: Bedside quantification of dead-space fraction using routine clinical data in patients with acute lung injury: secondary analysis of two prospective trials. Crit Care 2010, 14: R141. 10.1186/cc9206
Page B, Vieillard-Baron A, Beauchet A, Aegerter P, Prin S, Jardin F: Low stretch ventilation strategy in acute respiratory distress syndrome: eight years of clinical experience in a single center. Crit Care Med 2003, 31: 765-769. 10.1097/01.CCM.0000055402.68581.DC
Prin S, Chergui K, Augarde R, Page B, Jardin F, Vieillard-Baron A: Ability and safety of a heated humidifier to control hypercapnic acidosis in severe ARDS. Intensive Care Med 2002, 28: 1756-1760. 10.1007/s00134-002-1520-2
Vieillard-Baron A, Prin S, Schmitt JM, Augarde R, Page B, Beauchet A, Jardin F: Pressure-volume curves in acute respiratory distress syndrome: clinical demonstration of the influence of expiratory flow limitation on the initial slope. Am J Respir Crit Care Med 2002, 165: 1107-1112.
Nunn JF: Respiratory dead space and distribution of the inspired gas. In Applied Respiratory Physiology. London: Butterworth; 1969:179.
Roza AM, Shizgal HM: The Harris Benedict equation reevaluated: resting energy requirements and the body cell mass. Am J Clin Nutr 1984, 40: 168-182.
Rossi A, Gottfried SB, Higgs BD, Zocchi L, Grassino A, Milic-Emili J: Respiratory mechanics in mechanically ventilated patients with respiratory failure. J Appl Physiol 1985, 58: 1849-1858.
Koutsoukou A, Armaganidis A, Stavrakaki-Kallergi C, Vassilakopoulos T, Lymberis A, Roussos C, Milic-Emili J: Expiratory flow limitation and intrinsic positive end-expiratory pressure at zero positive end-expiratory pressure in patients with adult respiratory distress syndrome. Am J Respir Crit Care Med 2000, 161: 1590-1596.
Pelosi P, Tubiolo D, Mascheroni D, Vicardi P, Crotti S, Valenza F, Gattinoni L: Effects of the prone position on respiratory mechanics and gas exchange during acute lung injury. Am J Respir Crit Care Med 1998, 157: 387-393.
Protti A, Chiumello D, Cressoni M, Carlesso E, Mietto C, Berto V, Lazzerini M, Quintel M, Gattinoni L: Relationship between gas exchange response to prone position and lung recruitability during acute respiratory failure. Intensive Care Med 2009, 35: 1011-1017. 10.1007/s00134-009-1411-x
Albert RK, Leasa D, Sanderson M, Robertson HT, Hlastala MP: The prone position improves arterial oxygenation and reduces shunt in oleic-acid-induced acute lung injury. Am Rev Respir Dis 1987, 135: 628-633.
Lamm WJ, Graham MM, Albert RK: Mechanism by which the prone position improves oxygenation in acute lung injury. Am J Respir Crit Care Med 1994, 150: 184-193.
Blanch L, Mancebo J, Perez M, Martinez M, Mas A, Betbese AJ, Joseph D, Ballús J, Lucangelo U, Bak E: Short-term effects of prone position in critically ill patients with acute respiratory distress syndrome. Intensive Care Med 1997, 23: 1033-1039. 10.1007/s001340050453
Guerin C, Badet M, Rosselli S, Heyer L, Sab JM, Langevin B, Philit F, Fournier G, Robert D: Effects of prone position on alveolar recruitment and oxygenation in acute lung injury. Intensive Care Med 1999, 25: 1222-1230. 10.1007/s001340051050
Krayer S, Rehder K, Vettermann J, Didier EP, Ritman EL: Position and motion of the human diaphragm during anesthesia-paralysis. Anesthesiology 1989, 70: 891-898. 10.1097/00000542-198906000-00002
Richter T, Bellani G, Scott Harris R, Vidal Melo MF, Winkler T, Venegas JG, Musch G: Effect of prone position on regional shunt, aeration, and perfusion in experimental acute lung injury. Am J Respir Crit Care Med 2005, 172: 480-487. 10.1164/rccm.200501-004OC
Mancebo J, Fernández R, Blanch L, Rialp G, Gordo F, Ferrer M, Rodríguez F, Garro P, Ricart P, Vallverdú I, Gich I, Castaño J, Saura P, Domínguez G, Bonet A, Albert RK: A multicenter trial of prolonged prone ventilation in severe acute respiratory distress syndrome. Am J Respir Crit Care Med 2006, 173: 1233-1239. 10.1164/rccm.200503-353OC
Charron C, Bouferrache K, Caille V, Castro S, Aegerter P, Page B, Jardin F, Vieillard-Baron A: Routine prone position in patients with severe ARDS: feasibility and impacts on prognosis. Intensive Care Med 2011, 37: 796-800. 10.1007/s00134-011-2189-1
Murray J, Matthay M, Luce J, Flick M: An expanded definition of the adult respiratory distress syndrome. Am Rev Respir Dis 1988, 138: 720-723.