Öz

Objective: Mechanical power (MP) is a promising parameter that may guide lung-protective ventilation strategies. The MP equation encompasses all variables involved in the pathogenesis of ventilator-induced lung injury (VILI), as well as the inspiratory-to-expiratory (I:E) ratio. Shortening the inspiratory time—by altering the I:E ratio—increases gas flow and may lead to lung injury. The optimal I:E ratio for preventing VILI remains uncertain. The present study aimed to investigate the effects of different I:E ratios on inspiratory gas flow and MP in patients with acute respiratory distress syndrome (ARDS).

Materials and Methods: This study was conducted on 19 adult patients diagnosed with moderate ARDS who were admitted to the intensive care unit and received mechanical ventilation. Patients were ventilated at a PEEP level of 10 cmH2O, a tidal volume of 6 mL/kg, and three sequentially applied I:E ratios (1:2, 1:1, and 1.5:1), each maintained for 10 minutes. MP and respiratory parameters across the three I:E groups were compared using repeated-measures ANOVA.

Results: Compared with the I:E ratio of 1:2, ventilation with an I:E ratio of 1:1 resulted in slower inspiratory gas flow, lower inspiratory resistance and peak inspiratory pressure, higher dynamic compliance, and lower MP values. Plateau pressure and driving pressure did not differ significantly. When comparing I:E 1:1 with I:E 1.5:1, a persistent slowing of inspiratory gas flow was observed, but no significant difference in MP was detected.

Conclusion: In patients with ARDS, transitioning the I:E ratio from the conventional 1:2 to 1:1 or 1.5:1 resulted in progressively slower inspiratory gas flow and lower resistive and total mechanical power, suggesting that reducing inspiratory flow may enhance lung-protective ventilation.

Anahtar Kelimeler: ARDS, ventilator-induced lung injury, mechanical power, inspiratory-to-expiratory ratio

Referanslar

  1. Slutsky AS, Ranieri VM. Ventilator-induced lung injury. N Engl J Med. 2013;369:2126-36. https://doi.org/10.1056/NEJMra1208707
  2. Kumar A, Pontoppidan H, Falke KJ, Wilson RS, Laver MB. Pulmonary barotrauma during mechanical ventilation. Crit Care Med. 1973;1:181-6. https://doi.org/10.1097/00003246-197307000-00001
  3. Dreyfuss D, Soler P, Basset G, Saumon G. High inflation pressure pulmonary edema. Respective effects of high airway pressure, high tidal volume, and positive end-expiratory pressure. Am Rev Respir Dis. 1988;137:1159-64. https://doi.org/10.1164/ajrccm/137.5.1159
  4. Hotchkiss JR, Blanch L, Murias G, et al. Effects of decreased respiratory frequency on ventilator-induced lung injury. Am J Respir Crit Care Med. 2000;161:463-8. https://doi.org/10.1164/ajrccm.161.2.9811008
  5. Cressoni M, Gotti M, Chiurazzi C, et al. Mechanical power and development of ventilator-induced lung injury. Anesthesiology. 2016;124:1100-8. https://doi.org/10.1097/ALN.0000000000001056
  6. Gattinoni L, Tonetti T, Cressoni M, et al. Ventilator-related causes of lung injury: the mechanical power. Intensive Care Med. 2016;42:1567-75. https://doi.org/10.1007/s00134-016-4505-2
  7. Serpa Neto A, Deliberato RO, Johnson AEW, et al. Mechanical power of ventilation is associated with mortality in critically ill patients: an analysis of patients in two observational cohorts. Intensive Care Med. 2018;44:1914-22. https://doi.org/10.1007/s00134-018-5375-6
  8. Santini A, Collino F, Votta E, Protti A. Risk factors of ventilator-induced lung injury: mechanical power as surrogate of energy dissipation. J Emerg Crit Care Med. 2019;3:13. https://doi.org/10.21037/jeccm.2019.02.02
  9. Marini JJ. Evolving concepts for safer ventilation. Crit Care. 2019;23:114. https://doi.org/10.1186/s13054-019-2406-9
  10. Protti A, Maraffi T, Milesi M, et al. Role of strain rate in the pathogenesis of ventilator-induced lung edema. Crit Care Med. 2016;44:e838-45. https://doi.org/10.1097/CCM.0000000000001718
  11. Amato MB, Meade MO, Slutsky AS, et al. Driving pressure and survival in the acute respiratory distress syndrome. N Engl J Med. 2015;372:747-55. https://doi.org/10.1056/NEJMsa1410639
  12. Guérin C, Papazian L, Reignier J, et al. Effect of driving pressure on mortality in ARDS patients during lung protective mechanical ventilation in two randomized controlled trials. Crit Care. 2016;20:384. https://doi.org/10.1186/s13054-016-1556-2
  13. Bellani G. How respiratory mechanics are associated with outcome. Paper presented at: International Symposium on Intensive Care and Emergency Medicine (e-ISICEM); 2020 Sep 20.
  14. Schumann S, Goebel U, Haberstroh J, et al. Determination of respiratory system mechanics during inspiration and expiration by FLow-controlled EXpiration (FLEX): a pilot study in anesthetized pigs. Minerva Anestesiol. 2014;80:19-28.
  15. Bein T, Grasso S, Moerer O, et al. The standard of care of patients with ARDS: ventilatory settings and rescue therapies for refractory hypoxemia. Intensive Care Med. 2016;42:699-711. https://doi.org/10.1007/s00134-016-4325-4
  16. Ferguson ND, Fan E, Camporota L, et al. The Berlin definition of ARDS: an expanded rationale, justification, and supplementary material. Intensive Care Med. 2012;38:1573-82. https://doi.org/10.1007/s00134-012-2682-1
  17. Ashworth L, Norisue Y, Koster M, Anderson J, Takada J, Ebisu H. Clinical management of pressure control ventilation: an algorithmic method of patient ventilatory management to address “forgotten but important variables”. J Crit Care. 2018;43:169-82. https://doi.org/10.1016/j.jcrc.2017.08.046
  18. Barnes T, van Asseldonk D, Enk D. Minimisation of dissipated energy in the airways during mechanical ventilation by using constant inspiratory and expiratory flows - Flow-controlled ventilation (FCV). Med Hypotheses. 2018;121:167-76. https://doi.org/10.1016/j.mehy.2018.09.038
  19. Barnes T, Enk D. Ventilation for low dissipated energy achieved using flow control during both inspiration and expiration. Trends in Anaesthesia and Critical Care. 2019;24:5-12. https://doi.org/10.1016/j.tacc.2018.09.003
  20. Marini JJ. How I optimize power to avoid VILI. Crit Care. 2019;23:326. https://doi.org/10.1186/s13054-019-2638-8
  21. Müller-Redetzky HC, Felten M, Hellwig K, et al. Increasing the inspiratory time and I:E ratio during mechanical ventilation aggravates ventilator-induced lung injury in mice. Crit Care. 2015;19:23. https://doi.org/10.1186/s13054-015-0759-2

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Aşar S, Tontu F, Acicbe Ö, Çukurova Z, Hergünsel GO, Çakar N. The impact of the inspiratory-to-expiratory ratio on mechanical power in ARDS patients. Turk J Intensive Care. 2026;24(1):77-82. https://doi.org/10.63729/TJIC.2026.689