Effects of breathing patterns on mechanically ventilated patients with chronic obstructive pulmonary disease and dynamic hyperinflation

AbstractObjectiveTo examine the circulatory and respiratory effects of breathing pattern in patients with chronic obstructive pulmonary disease (COPD) and dynamic hyperinflation (DH) during controlled mechanical ventilation.DesignProspective, controlled, randomized, non-blinded study.SettingRespiratory intensive care unit of a university hospital.PatientsNine patients with acute respiratory failure and DH due to acute exacerbations of COPD.InterventionsKeeping tidal volume and total breath duration (TTOT) constant, patients were ventilated at six different values of expiratory time (TE). TE changes were randomly induced by alterations of constant inspiratory flow $$\left( {\dot V_1 } \right)$$ and/or end-inspiratory pause (EIP). Patients were studied at three levels of $$\dot V_1 $$ (0.93±0.08, 0.72±0.06 and 0.55±0.04 l/s, mean ±SE), with and without EIP (10% of TTOT).Measurements and resultsLung volumes, airflows, airways pressures, oxygenation indices and dead space were measured. Alveolar pressure and airway resistance (Rmin), as well as the additional resistance (δR) due to viscoelastic pressure dissipation and time-constant inequalities, were estimated by rapid airway occlusion during inflation. In seven out of nine patients, right-heart catheterization was performed and hemodynamic parameters were obtained at each value of TE. A significant decrease of intrinsic positive end-expiratory pressure (PEEPi), end-inspiratory static and mean (mPaw) airway pressures, end-expiratory lung volume above passive FRC (Vtrap), δR and venous admixture and a significant increase of peak airway pressure, Rmin, stroke volume index and mixed venous PO2 $$\left( {P\bar vO_2 } \right)$$ were observed when $$\dot V_1 $$ increased. At each $$\dot V_1 $$ , the addition of EIP significantly decreased iso-volume expiratory flows and $$P\bar vO_2 $$ and increased Vtrap and mPaw.ConclusionsWe conclude that in mechanically ventilated patients with COPD, the pattern of lung inflation and TE alteration have a significant impact on respiratory system mechanics, gas exchange and hemodynamics. Addition of EIP in patients with COPD may be detrimental.

[1]  A. Rossi,et al.  Respiratory mechanics during the first day of mechanical ventilation in patients with pulmonary edema and chronic airway obstruction. , 1988, The American review of respiratory disease.

[2]  B. Fleury,et al.  Work of breathing in patients with chronic obstructive pulmonary disease in acute respiratory failure. , 2015, The American review of respiratory disease.

[3]  A. Connors,et al.  Effect of Inspiratory Flow Rate on Gas Exchange during Mechanical Ventilation , 1982 .

[4]  J. Marini.  Should PEEP be used in airflow obstruction? , 1989, The American review of respiratory disease.

[5]  高地 哲夫.  Flow and volume dependence of pulmonary mechanics in anesthetized cats , 1989 .

[6]  P. Carlile,et al.  Effect of opposite changes in cardiac output and arterial PO2 on the relationship between mixed venous PO2 and oxygen transport. , 1989, The American review of respiratory disease.

[7]  V. Ranieri,et al.  Analysis of behavior of the respiratory system in ARDS patients: effects of flow, volume, and time. , 1991, Journal of applied physiology.

[8]  E. R. Ruzicka,et al.  Oxygen therapy. , 1950, The Surgical clinics of North America.

[9]  P. Pelosi,et al.  The effects of positive end-expiratory pressure on respiratory resistance in patients with the adult respiratory distress syndrome and in normal anesthetized subjects. , 1991, The American review of respiratory disease.

[10]  A. Layon,et al.  Pressure-present ventilation. Part 1: Physiologic and mechanical considerations. , 1993, Chest.

[11]  A. Layon,et al.  Pressure-preset ventilation. Part 2: Mechanics and safety. , 1993, Chest.

[12]  N. Eissa,et al.  Lung and chest wall mechanics in mechanically ventilated COPD patients. , 1993, Journal of applied physiology.

[13]  E. Wu,et al.  Monte Carlo calculation of temperature dependence of the transport properties in compensated GaAs , 1991 .

[14]  J. Milic-Emili,et al.  Dependence of maximal flow-volume curves on time course of preceding inspiration. , 1993, Journal of applied physiology.

[15]  R. Wilson,et al.  Effect of Mechanical Ventilation with End‐inspiratory Pause on Blood‐Gas Exchange , 1976, Anesthesia and analgesia.

[16]  M. Younes,et al.  Effect of inspiratory flow rate on respiratory output in normal subjects. , 1992, The American review of respiratory disease.

[17]  J. Milic-Emili,et al.  Respiratory mechanics in anesthetized paralyzed humans: effects of flow, volume, and time. , 1989, Journal of applied physiology.

[18]  P E Pepe,et al.  Occult positive end-expiratory pressure in mechanically ventilated patients with airflow obstruction: the auto-PEEP effect. , 1982, The American review of respiratory disease.

[19]  A Rossi,et al.  Analysis of the behavior of the respiratory system with constant inspiratory flow. , 1985, Journal of applied physiology.

[20]  J. Marini,et al.  Mean airway pressure: Physiologic determinants and clinical importance‐Part 2 Clinical implications , 1992, Critical care medicine.

[21]  J. Marini,et al.  Mean airway pressure: Physiologic determinants and clinical importance—Part 1 Physiologic determinants and measurements , 1992, Critical care medicine.

[22]  J. Calvin,et al.  Right ventricular pressure overload during acute lung injury: Cardiac mechanics and the pathophysiology of right ventricular systolic dysfunction , 1989 .

[23]  J B West,et al.  Pulmonary gas exchange. , 1998, International review of physiology.

[24]  M. Tavola,et al.  Pulmonary and chest wall mechanics in anesthetized paralyzed humans. , 1991, Journal of applied physiology.

[25]  A. Webb,et al.  Severe bronchial asthma requiring ventilation. A review of 20 cases and advice on management. , 1979, Postgraduate medical journal.

[26]  G. Bowes,et al.  Risk factors for morbidity in mechanically ventilated patients with acute severe asthma. , 1992, The American review of respiratory disease.

[27]  D. Tuxen,et al.  The effects of ventilatory pattern on hyperinflation, airway pressures, and circulation in mechanical ventilation of patients with severe air-flow obstruction. , 1987, The American review of respiratory disease.

[28]  A Rossi,et al.  Respiratory mechanics in mechanically ventilated patients with respiratory failure. , 1985, Journal of applied physiology.

[29]  V. Ranieri,et al.  Physiologic effects of positive end-expiratory pressure in patients with chronic obstructive pulmonary disease during acute ventilatory failure and controlled mechanical ventilation. , 1993, The American review of respiratory disease.

[30]  E. Giannouli,et al.  Effects of extrinsic positive end-expiratory pressure on mechanically ventilated patients with chronic obstructive pulmonary disease and dynamic hyperinflation , 2005, Intensive Care Medicine.

[31]  V. Ranieri,et al.  Respiratory mechanics in ventilated patients , 1992 .

[32]  D. Georgopoulos,et al.  Factors determining lobar emptying during maximal and partial forced deflations in nonhomogeneous airway obstruction in dogs. , 1994, American journal of respiratory and critical care medicine.