Official reprint from UpToDate®
www.uptodate.com ©2018 UpToDate, Inc. and/or its affiliates. All Rights Reserved.

Modes of mechanical ventilation

Robert C Hyzy, MD
Section Editor
Polly E Parsons, MD
Deputy Editor
Geraldine Finlay, MD


Numerous decisions need to be made once it is determined that a patient requires mechanical ventilation, including the mode of mechanical ventilation. The mode refers to the method of inspiratory support. Its selection is generally based on clinician familiarity and institutional preferences since there is a paucity of evidence indicating that the mode affects clinical outcome.

Common modes of mechanical ventilation are described in this topic review (table 1). Other aspects of initiating mechanical ventilation are discussed separately. (See "Overview of mechanical ventilation".)


Volume-limited ventilation (also called volume-controlled or volume-cycled ventilation) requires the clinician to set the peak flow rate, flow pattern, tidal volume, respiratory rate, positive end-expiratory pressure (applied PEEP, also known as extrinsic PEEP), and fraction of inspired oxygen (FiO2). Inspiration ends after delivery of the set tidal volume.

The inspiratory time and inspiratory to expiratory (I:E) ratio are determined by the peak inspiratory flow rate. Increasing the peak inspiratory flow rate will decrease inspiratory time, increase expiratory time, and decrease the I:E ratio.

Airway pressures (peak, plateau, and mean) depend on both the ventilator settings and patient-related variables (eg, compliance, airway resistance). High airway pressures may be a consequence of large tidal volumes, a high peak flow, poor compliance (eg, acute respiratory distress syndrome, minimal sedation), or increased airway resistance (figure 1 and waveform 1).

To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information on subscription options, click below on the option that best describes you:

Subscribers log in here

Literature review current through: Dec 2017. | This topic last updated: Nov 04, 2016.
The content on the UpToDate website is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. The use of this website is governed by the UpToDate Terms of Use ©2018 UpToDate, Inc.
  1. Christopher KL, Neff TA, Bowman JL, et al. Demand and continuous flow intermittent mandatory ventilation systems. Chest 1985; 87:625.
  2. Sassoon CS, Del Rosario N, Fei R, et al. Influence of pressure- and flow-triggered synchronous intermittent mandatory ventilation on inspiratory muscle work. Crit Care Med 1994; 22:1933.
  3. Marini JJ, Smith TC, Lamb VJ. External work output and force generation during synchronized intermittent mechanical ventilation. Effect of machine assistance on breathing effort. Am Rev Respir Dis 1988; 138:1169.
  4. Groeger JS, Levinson MR, Carlon GC. Assist control versus synchronized intermittent mandatory ventilation during acute respiratory failure. Crit Care Med 1989; 17:607.
  5. Esteban A, Anzueto A, Alía 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.
  6. Weisman IM, Rinaldo JE, Rogers RM, Sanders MH. Intermittent mandatory ventilation. Am Rev Respir Dis 1983; 127:641.
  7. MacIntyre NR. Pressure-limited versus volume-cycled breath delivery strategies. Crit Care Med 1994; 22:4.
  8. Abraham E, Yoshihara G. Cardiorespiratory effects of pressure controlled ventilation in severe respiratory failure. Chest 1990; 98:1445.
  9. Rappaport SH, Shpiner R, Yoshihara G, et al. Randomized, prospective trial of pressure-limited versus volume-controlled ventilation in severe respiratory failure. Crit Care Med 1994; 22:22.
  10. 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.
  11. Chiumello D, Pelosi P, Calvi E, et al. Different modes of assisted ventilation in patients with acute respiratory failure. Eur Respir J 2002; 20:925.
  12. Muñoz J, Guerrero JE, Escalante JL, et al. Pressure-controlled ventilation versus controlled mechanical ventilation with decelerating inspiratory flow. Crit Care Med 1993; 21:1143.
  13. MacIntyre NR. Respiratory function during pressure support ventilation. Chest 1986; 89:677.
  14. MacIntyre NR, McConnell R, Cheng KC, Sane A. Patient-ventilator flow dyssynchrony: flow-limited versus pressure-limited breaths. Crit Care Med 1997; 25:1671.
  15. Chiumello D, Pelosi P, Taccone P, et al. Effect of different inspiratory rise time and cycling off criteria during pressure support ventilation in patients recovering from acute lung injury. Crit Care Med 2003; 31:2604.
  16. Fiastro JF, Habib MP, Quan SF. Pressure support compensation for inspiratory work due to endotracheal tubes and demand continuous positive airway pressure. Chest 1988; 93:499.
  17. Banner MJ, Kirby RR, Blanch PB, Layon AJ. Decreasing imposed work of the breathing apparatus to zero using pressure-support ventilation. Crit Care Med 1993; 21:1333.
  18. Brochard L, Rua F, Lorino H, et al. Inspiratory pressure support compensates for the additional work of breathing caused by the endotracheal tube. Anesthesiology 1991; 75:739.
  19. Parthasarathy S, Tobin MJ. Effect of ventilator mode on sleep quality in critically ill patients. Am J Respir Crit Care Med 2002; 166:1423.
  20. Fabry B, Guttmann J, Eberhard L, et al. An analysis of desynchronization between the spontaneously breathing patient and ventilator during inspiratory pressure support. Chest 1995; 107:1387.
  21. Thille AW, Rodriguez P, Cabello B, et al. Patient-ventilator asynchrony during assisted mechanical ventilation. Intensive Care Med 2006; 32:1515.
  22. Toublanc B, Rose D, Glérant JC, et al. Assist-control ventilation vs. low levels of pressure support ventilation on sleep quality in intubated ICU patients. Intensive Care Med 2007; 33:1148.
  23. Zeravik J, Borg U, Pfeiffer UJ. Efficacy of pressure support ventilation dependent on extravascular lung water. Chest 1990; 97:1412.
  24. Tokioka H, Saito S, Kosaka F. Comparison of pressure support ventilation and assist control ventilation in patients with acute respiratory failure. Intensive Care Med 1989; 15:364.
  25. Vitacca M, Bianchi L, Zanotti E, et al. Assessment of physiologic variables and subjective comfort under different levels of pressure support ventilation. Chest 2004; 126:851.
  26. Slutsky AS. Mechanical ventilation. American College of Chest Physicians' Consensus Conference. Chest 1993; 104:1833.
  27. Marini JJ, Crooke PS 3rd, Truwit JD. Determinants and limits of pressure-preset ventilation: a mathematical model of pressure control. J Appl Physiol (1985) 1989; 67:1081.
  28. Jubran A, Van de Graaff WB, Tobin MJ. Variability of patient-ventilator interaction with pressure support ventilation in patients with chronic obstructive pulmonary disease. Am J Respir Crit Care Med 1995; 152:129.
  29. Chiumello D, Polli F, Tallarini F, et al. Effect of different cycling-off criteria and positive end-expiratory pressure during pressure support ventilation in patients with chronic obstructive pulmonary disease. Crit Care Med 2007; 35:2547.
  30. Cohen JD, Shapiro M, Grozovski E, et al. Extubation outcome following a spontaneous breathing trial with automatic tube compensation versus continuous positive airway pressure. Crit Care Med 2006; 34:682.
  31. Downs JB, Stock MC. Airway pressure release ventilation: a new concept in ventilatory support. Crit Care Med 1987; 15:459.
  32. Stock MC, Downs JB, Frolicher DA. Airway pressure release ventilation. Crit Care Med 1987; 15:462.
  33. Putensen C, Zech S, Wrigge H, et al. Long-term effects of spontaneous breathing during ventilatory support in patients with acute lung injury. Am J Respir Crit Care Med 2001; 164:43.
  34. Putensen C, Mutz NJ, Putensen-Himmer G, Zinserling J. Spontaneous breathing during ventilatory support improves ventilation-perfusion distributions in patients with acute respiratory distress syndrome. Am J Respir Crit Care Med 1999; 159:1241.
  35. Neumann P, Golisch W, Strohmeyer A, et al. Influence of different release times on spontaneous breathing pattern during airway pressure release ventilation. Intensive Care Med 2002; 28:1742.
  36. Dart BW 4th, Maxwell RA, Richart CM, et al. Preliminary experience with airway pressure release ventilation in a trauma/surgical intensive care unit. J Trauma 2005; 59:71.
  37. Bugedo G, Bruhn A, Hernández G, et al. Lung computed tomography during a lung recruitment maneuver in patients with acute lung injury. Intensive Care Med 2003; 29:218.
  38. Räsänen J, Cane RD, Downs JB, et al. Airway pressure release ventilation during acute lung injury: a prospective multicenter trial. Crit Care Med 1991; 19:1234.
  39. Valente Barbas CS. Lung recruitment maneuvers in acute respiratory distress syndrome and facilitating resolution. Crit Care Med 2003; 31:S265.
  40. Varpula T, Valta P, Niemi R, et al. Airway pressure release ventilation as a primary ventilatory mode in acute respiratory distress syndrome. Acta Anaesthesiol Scand 2004; 48:722.
  41. Kaplan LJ, Bailey H, Formosa V. Airway pressure release ventilation increases cardiac performance in patients with acute lung injury/adult respiratory distress syndrome. Crit Care 2001; 5:221.
  42. Hering R, Peters D, Zinserling J, et al. Effects of spontaneous breathing during airway pressure release ventilation on renal perfusion and function in patients with acute lung injury. Intensive Care Med 2002; 28:1426.
  43. Rouby JJ, Ben Ameur M, Jawish D, et al. Continuous positive airway pressure (CPAP) vs. intermittent mandatory pressure release ventilation (IMPRV) in patients with acute respiratory failure. Intensive Care Med 1992; 18:69.
  44. Seymour CW, Frazer M, Reilly PM, Fuchs BD. Airway pressure release and biphasic intermittent positive airway pressure ventilation: are they ready for prime time? J Trauma 2007; 62:1298.
  45. Rose L, Hawkins M. Airway pressure release ventilation and biphasic positive airway pressure: a systematic review of definitional criteria. Intensive Care Med 2008; 34:1766.
  46. Brunner JX, Laubscher TP, Banner MJ, et al. Simple method to measure total expiratory time constant based on the passive expiratory flow-volume curve. Crit Care Med 1995; 23:1117.
  47. Lourens MS, van den Berg B, Aerts JG, et al. Expiratory time constants in mechanically ventilated patients with and without COPD. Intensive Care Med 2000; 26:1612.
  48. Belliato M, Palo A, Pasero D, et al. Evaluation of adaptive support ventilation in paralysed patients and in a physical lung model. Int J Artif Organs 2004; 27:709.
  49. Arnal JM, Wysocki M, Nafati C, et al. Automatic selection of breathing pattern using adaptive support ventilation. Intensive Care Med 2008; 34:75.
  50. Verbrugghe W, Jorens PG. Neurally adjusted ventilatory assist: a ventilation tool or a ventilation toy? Respir Care 2011; 56:327.
  51. Piquilloud L, Vignaux L, Bialais E, et al. Neurally adjusted ventilatory assist improves patient-ventilator interaction. Intensive Care Med 2011; 37:263.
  52. Schmidt M, Kindler F, Cecchini J, et al. Neurally adjusted ventilatory assist and proportional assist ventilation both improve patient-ventilator interaction. Crit Care 2015; 19:56.
  53. Demoule A, Clavel M, Rolland-Debord C, et al. Neurally adjusted ventilatory assist as an alternative to pressure support ventilation in adults: a French multicentre randomized trial. Intensive Care Med 2016; 42:1723.
  54. Mercat A, Graïni L, Teboul JL, et al. Cardiorespiratory effects of pressure-controlled ventilation with and without inverse ratio in the adult respiratory distress syndrome. Chest 1993; 104:871.
  55. Mercat A, Diehl JL, Michard F, et al. Extending inspiratory time in acute respiratory distress syndrome. Crit Care Med 2001; 29:40.
  56. Shanholtz C, Brower R. Should inverse ratio ventilation be used in adult respiratory distress syndrome? Am J Respir Crit Care Med 1994; 149:1354.
  57. Mercat A, Titiriga M, Anguel N, et al. Inverse ratio ventilation (I/E = 2/1) in acute respiratory distress syndrome: a six-hour controlled study. Am J Respir Crit Care Med 1997; 155:1637.
  58. Wang SH, Wei TS. The outcome of early pressure-controlled inverse ratio ventilation on patients with severe acute respiratory distress syndrome in surgical intensive care unit. Am J Surg 2002; 183:151.
  59. Sydow M, Burchardi H, Ephraim E, et al. Long-term effects of two different ventilatory modes on oxygenation in acute lung injury. Comparison of airway pressure release ventilation and volume-controlled inverse ratio ventilation. Am J Respir Crit Care Med 1994; 149:1550.
  60. Abraham E, Yoshihara G. Cardiorespiratory effects of pressure controlled inverse ratio ventilation in severe respiratory failure. Chest 1989; 96:1356.
  61. Amato MB, Barbas CS, Medeiros DM, et al. Beneficial effects of the "open lung approach" with low distending pressures in acute respiratory distress syndrome. A prospective randomized study on mechanical ventilation. Am J Respir Crit Care Med 1995; 152:1835.
  62. Gurevitch MJ, Van Dyke J, Young ES, Jackson K. Improved oxygenation and lower peak airway pressure in severe adult respiratory distress syndrome. Treatment with inverse ratio ventilation. Chest 1986; 89:211.
  63. Tharratt RS, Allen RP, Albertson TE. Pressure controlled inverse ratio ventilation in severe adult respiratory failure. Chest 1988; 94:755.
  64. Papadakos PJ, Halloran W, Hessney JI, et al. The use of pressure-controlled inverse ratio ventilation in the surgical intensive care unit. J Trauma 1991; 31:1211.
  65. Lain DC, DiBenedetto R, Morris SL, et al. Pressure control inverse ratio ventilation as a method to reduce peak inspiratory pressure and provide adequate ventilation and oxygenation. Chest 1989; 95:1081.
  66. Chan K, Abraham E. Effects of inverse ratio ventilation on cardiorespiratory parameters in severe respiratory failure. Chest 1992; 102:1556.
  67. Esteban A, Alía I, Gordo F, et al. Prospective randomized trial comparing pressure-controlled ventilation and volume-controlled ventilation in ARDS. For the Spanish Lung Failure Collaborative Group. Chest 2000; 117:1690.
  68. Lachmann B. Open up the lung and keep the lung open. Intensive Care Med 1992; 18:319.
  69. Armstrong BW Jr, MacIntyre NR. Pressure-controlled, inverse ratio ventilation that avoids air trapping in the adult respiratory distress syndrome. Crit Care Med 1995; 23:279.