Mechanical power in AVM-2 versus conventional ventilation modes in a normal lung model: A bench study

Parthav Shah, Jihun Yeo, Witina Techasatian, Claudio Luciano Franck, Ehab Daoud

Abstract

Introduction

Recent studies suggested that the energy delivered by the mechanical ventilator to the lungs termed the mechanical power can induce and increase the risks of ventilator induced lung injury. The components of the mechanical power include the variables delivered by the ventilator: tidal volume, respiratory rate, inspiratory flow, airway pressure. Adaptive Ventilator Mode-2 (AVM-2) is a pressure-controlled mode with an optimal targeting scheme based on the inspiratory power equation that adjusts the respiratory rate and tidal volume to achieve a target minute ventilation. This mode conceptually should reduce the mechanical power delivered to the patients and thus reduce the incidence of ventilator induced lung injury.

Methodology

A bench study using a lung simulator (TTL, Michigan Instruments, Michigan, USA) was conducted. We constructed a passive single compartment normal respiratory mechanics model with compliance of 50 ml/cmH₂O, and resistance of 10 cmH₂O/L/s, with IBW 70 kg. We compared three different ventilator modes: Adaptive Ventilation Mode-2 (AVM-2), Pressure Regulated Volume Control (PRVC), and Volume Controlled Ventilation (VCV) in four different scenarios: 2 levels of minute ventilation 7 and 10.5 Lit/min (Experiment 1 and 2 respectively), each with 2 different PEEP levels 5 and 10 cmH₂O (Experiment A and B respectively) termed Experiments 1A, 1B, 2A, and 2B respectively.

The AVM-2 mode automatically selects the optimal tidal volume, and respiratory rate per the dialed percent minute ventilation with an I:E ratio of 1:1. In the PRVC, VCV we selected target tidal volume 6ml/kg/IBW (420 ml), and respiratory rate adjusted to match the minute ventilation for the AVM-2 mode. I:E ratio was kept 1:2 to avoid intrinsic PEEP. The study was conducted using a bellavista™ 1000 e Ventilator (Vyaire Medical, Illinois, USA). 

The mechanical power delivered by the ventilator for each mode was computed and compared between the three modes in each experiment. Statistical analysis was done using Kruskal-Wallis test to analyze the difference between the three modes, post HOC Tukey test was used to analyze the difference between each mode with the confidence intervals, P < 0.05 was considered statistically significant.

Results

There were statistically significant differences between all the three modes regarding the ventilator delivered mechanical power. The AVM-2 mode delivered significantly less mechanical power than VCV which in turn was less than PRVC. Experiment 1A: AVM-2 8.76 土 0.05, VCV 9.78 土 0.04, PRVC 10.82 土 0.08, P < 0.001 Experiment 1B: AVM-2 11.27 ± 0.09 VCV 12.81 ± 0.05, PRVC 13.88 ± 0.06, P < 0.001. Experiment 2A: AVM-2 14.76 ± 0.05, VCV 15.79 ± 0.05, PRVC 18.29 ± 0.07, P < 0.001, Experiment 2B: AVM-2 18.76 ± 0.04, VCV 20.56 ± 0.04, PRVC 21.17 土 0.03, P < 0.001.

Conclusion 

AVM2 mode delivered less mechanical power compared to two conventional modes using low tidal volume in a normal lung model. This might reduce the incidence of ventilator induced lung injury. Results need to be validated in more clinical studies.

Keywords

AVM-2, Mechanical power, VILI

References

1. Kumar A, Pontoppidan H, Falke KJ, et al. Pulmonary barotrauma during mechanical ventilation. Crit Care Med 1973; 1(4):181-186. https://doi.org/10.1097/00003246-197307000-00001 PMid:4587509

2. Dreyfuss D, Soler P, Basset G, et al. 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(5):1159-1164. https://doi.org/10.1164/ajrccm/137.5.1159 PMid:3057957

3. 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(9):e838-e845. https://doi.org/10.1097/CCM.0000000000001718 PMid:27054894

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(2):463-468. https://doi.org/10.1164/ajrccm.161.2.9811008 PMid:10673186

5. Cruz FF, Ball L, Rocco PRM, et al. Ventilator-induced lung injury during controlled ventilation in patients with acute respiratory distress syndrome: less is probably better. Expert Rev Respir Med 2018; 12(5):403-414. https://doi.org/10.1080/17476348.2018.1457954 PMid:29575957

6. Dreyfuss D, Saumon G. Ventilator-induced lung injury: lessons from experimental studies. Am J Respir Crit Care Med 1998; 157(1):294-323. https://doi.org/10.1164/ajrccm.157.1.9604014 PMid:9445314

7. Acute Respiratory Distress Syndrome Network, Brower RG, Matthay MA, Morris A, et al. 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(18):1301-1308. https://doi.org/10.1056/NEJM200005043421801 PMid:10793162

8. Neye H, Verspohl EJ. The FK506 binding protein 13 kDa (FKBP13) interacts with the C-chain of complement C1q. BMC Pharmacol 2004; 4:19. https://doi.org/10.1186/1471-2210-4-19 PMid:15353007 PMCid:PMC520748

9. Fu Z, Costello ML, Tsukimoto K, et al. High lung volume increases stress failure in pulmonary capillaries. J Appl Physiol 1992; 73(1):123-133. https://doi.org/10.1152/jappl.1992.73.1.123 PMid:1506359

10. Tremblay L, Valenza F, Ribeiro SP, et al. Injurious ventilatory strategies increase cytokines and c-fos m-RNA expression in an isolated rat lung model. J Clin Invest 1997; 99(5):944-952. https://doi.org/10.1172/JCI119259 PMid:9062352 PMCid:PMC507902

11. Imai Y, Parodo J, Kajikawa O, et al. Injurious mechanical ventilation and end-organ epithelial cell apoptosis and organ dysfunction in an experimental model of acute respiratory distress syndrome. JAMA 2003; 289(16):2104-2112. https://doi.org/10.1001/jama.289.16.2104 PMid:12709468

12. Marini JJ. Evolving concepts for safer ventilation. Crit Care 2019; 23(Suppl 1):114. https://doi.org/10.1186/s13054-019-2406-9 PMid:31200734 PMCid:PMC6570627

13. Marini JJ. Dissipation of energy during the respiratory cycle: conditional importance of ergotrauma to structural lung damage. Curr Opin Crit Care 2018; 24(1):16-22 https://doi.org/10.1097/MCC.0000000000000470 PMid:29176330

14. Gattinoni L, Tonetti T, Cressoni M, et al. Ventilator-related causes of lung injury: the mechanical power. Intensive Care Med 2016; 42(10):1567-1575. https://doi.org/10.1007/s00134-016-4505-2 PMid:27620287

15. Botta M, Tsonas AM, Pillay J, et al. Ventilation management and clinical outcomes in invasively ventilated patients with COVID-19 (PRoVENT-COVID): a national, multicentre, observational cohort study. Lancet Respir Med 2021; 9(2):139-148. https://doi.org/10.1016/S2213-2600(20)30459-8

16. Hong Y, Chen L, Pan Q, et al. Individualized mechanical power-based ventilation strategy for acute respiratory failure formalized by finite mixture modeling and dynamic treatment regimen. EClinicalMedicine 2021; 36:100898. https://doi.org/10.1016/j.eclinm.2021.100898 PMid:34041461 PMCid:PMC8144670

17. van der Staay M, Chatburn RL. Advanced modes of mechanical ventilation and optimal targeting schemes. Intensive Care Med Exp 2018; 22;6(1):30. https://doi.org/10.1186/s40635-018-0195-0 PMid:30136011 PMCid:PMC6104409

18. Wu S-H, Kor C-T, Mao I-C, et al. Accuracy of calculating mechanical power of ventilation by one commonly used equation. J Clin Monit Comput 2022. Published online April 15, 2022:1-7. https://doi.org/10.1007/s10877-022-00823-3

19. Arnal JM, Garnero A, Saoli M, Chatburn RL. Parameters for Simulation of Adult Subjects During Mechanical Ventilation. Respir Care. 2018 Feb;63(2):158-168. https://doi.org/10.4187/respcare.05775 PMid:29042486

20. Chatburn RL. Four truths of mechanical ventilation and the ten-fold path to enlightenment. J Mech Vent 2021; 2(3):73-78. https://doi.org/10.53097/JMV.10028

21. Daoud EG, Yamasaki K, Sanderson R, Shokry M. Mechanical ventilation modes utilization. An international survey of clinicians. J Mech Vent 2021; 2(3):105-111. https://doi.org/10.53097/JMV.10031

22. Amato MBP, Barbas CSV, Medeiros DM, et al. Effect of a protective-ventilation strategy on mortality in the acute respiratory distress syndrome. N Engl J Med 1998; 338(6):347-354. https://doi.org/10.1056/NEJM199802053380602 PMid:9449727

23. Determann RM, Royakkers A, Wolthuis EK, et al. Ventilation with lower tidal volumes as compared with conventional tidal volumes for patients without acute lung injury: a preventive randomized controlled trial. Crit Care 2010; 14(1):R1. https://doi.org/10.1186/cc8230 PMid:20055989 PMCid:PMC2875503

24. Serpa Neto A, Simonis FD, Barbas CSV, et al. Association between tidal volume size, duration of ventilation, and sedation needs in patients without acute respiratory distress syndrome: an individual patient data meta-analysis. Intensive Care Med 2014; 40(7):950-957. https://doi.org/10.1007/s00134-014-3318-4 PMid:24811940

25. Amato MBP, Meade MO, Slutsky AS, et al. Driving pressure and survival in the acute respiratory distress syndrome. N Engl J Med 2015; 372(8):747-755. https://doi.org/10.1056/NEJMsa1410639 PMid:25693014

26. Marini JJ. How I optimize power to avoid VILI. Crit Care 2019;23(1):326. https://doi.org/10.1186/s13054-019-2638-8 PMid:31639025 PMCid:PMC6805433

27. Silva PL, Ball L, Rocco PRM, et al. Power to mechanical power to minimize ventilator-induced lung injury? Intensive care Med Exp 2019; 7(Suppl 1):38. https://doi.org/10.1186/s40635-019-0243-4 PMid:31346828 PMCid:PMC6658623

28. 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(11):1914-1922. https://doi.org/10.1007/s00134-018-5375-6 PMid:30291378

29. Schultz MJ. Lung-protective mechanical ventilation with lower tidal volumes in patients not suffering from acute lung injury: a review of clinical studies. Med Sci Monit 2008; 14(2):RA22-26. PMID: 18227773

30. van der Staay M, Remus C. Adaptive ventilation mode 2. 2017. https://downloads.imt.ch/usdavkarsv/ scientificNote_AVM2.pdf.

31. Becher T, Adelmeier A, Frerichs I, et al. Adaptive mechanical ventilation with automated minimization of mechanical power-a pilot randomized cross-over study. Crit Care 2019; 23(1):338. https://doi.org/10.1186/s13054-019-2610-7 PMid:31666136 PMCid:PMC6822420

32. Marini JJ, Jaber S. Dynamic predictors of VILI risk: beyond the driving pressure. Intensive Care Med 2016; 42(10):1597-1600. https://doi.org/10.1007/s00134-016-4534-x PMid:27637717

33. Arnal JM, Saoli M, Garnero A. Airway and transpulmonary driving pressures and mechanical powers selected by INTELLiVENT-ASV in passive, mechanically ventilated ICU patients. Heart Lung 2020; 49(4):427-434. https://doi.org/10.1016/j.hrtlng.2019.11.001 PMid:31733881

34. Coppola, S, Caccioppola, A, Froio S. et al. Effect of mechanical power on intensive care mortality in ARDS patients. Crit Care 2020; 24:246. https://doi.org/10.1186/s13054-020-02963-x PMid:32448389 PMCid:PMC7245621

35. Davies JD, Senussi MH, Mireles-Cabodevila E. Should A tidal volume of 6 mL/kg be used in all patients? Respir Care 2016; 61(6):774-790. https://doi.org/10.4187/respcare.04651 PMid:27235313

36. Vassali F, Pasticci I, Romitti F, et al. Does iso-mechanical power lead to iso-lung damage? An experimental study in a porcine model. Anesthesiology 2020; 132:1126-1137. https://doi.org/10.1097/ALN.0000000000003189 PMid:32032095

37. Gattinoni L, Marini JJ, Collino Fet al. The future of mechanical ventilation: lessons from the present and the past. Crit Care 2017; 21(183):1-11. https://doi.org/10.1186/s13054-017-1750-x PMid:28701178 PMCid:PMC5508674

38. Giosa L, Busana M, Pasticci I, et al. Mechanical power at a glance: a Simple surrogate for volume-controlled ventilation. Intensive Care Medicine Experimental 2019; 7(61): 2-13. https://doi.org/10.1186/s40635-019-0276-8 PMid:31773328 PMCid:PMC6879677

39. Chiumello D, Gotti M, Guanziroli M, et al. Bedside calculation of mechanical power during volume- and pressure-controlled mechanical ventilation. Crit Care 2020; 24(1):417. https://doi.org/10.1186/s13054-020-03116-w PMid:32653011 PMCid:PMC7351639