The Effect of Recruitment Maneuvers on Dead Space in Patients with ARDS: Prospective Observational Study

Abstract

Objective: Acute Respiratory Distress Syndrome (ARDS) is characterized by severe hypoxemia and heterogeneous lung involvement. Recruitment maneuvers (RMs) and positive end-expiratory pressure (PEEP) titration are commonly employed strategies in lung-protective ventilation to reopen collapsed alveoli and improve oxygenation. However, the effect of these strategies on dead space—a key indicator of ventilation-perfusion mismatch—remains underexplored. This study aimed to investigate the impact of RMs and PEEP titration on dead space in patients with ARDS. Material and Method: This prospective observational study included twelve early-phase ARDS patients. After initial stabilization, each patient underwent a standard RM protocol followed by decremental PEEP titration. Dead space parameters, lung mechanics, blood gases, and hemodynamic variables were measured before and after RM and individualized PEEP titration. Results: A statistically significant reduction in both airway and physiological dead space was observed following RM. PaO₂ and oxygen saturation increased, while arterial pH decreased modestly. Alveolar dead space, compliance, airway pressures, end-tidal CO₂, and hemodynamics did not change significantly. Conclusion: Individualized ventilation strategies with RMs and PEEP may reduce physiological dead space and improve oxygenation in early ARDS without causing significant hemodynamic compromise. These findings suggest that incorporating dead space monitoring could be considered in personalized approaches to help optimize gas exchange and potentially improve clinical outcomes

Keywords

• Acute Respiratory Distress Syndrome (ARDS)
• Dead space
• Recruitment maneuver
• PEEP
• Mechanical ventilation
• Respiratory mechanics
• Ventilation-Perfusion ratio

ARDS Hastalarında Recruitment Manevralarının Ölü Boşluk Üzerine Etkisi: Prospektif Gözlemsel Çalışma

Abstract

Amaç: Akut Solunum Sıkıntısı Sendromu (ARDS), şiddetli hipoksemi ve heterojen akciğer tutulumuyla karakterizedir. Rekruitman manevraları (RM) ve pozitifi son ekspiryum basıncı (PEEP) titrasyonu, kollabe alveollerin yeniden açılmasını sağlamak ve oksijenasyonu artırmak amacıyla akciğer koruyucu ventilasyon stratejileri kapsamında yaygın olarak kullanılmaktadır. Ancak, bu stratejilerin ventilasyon-perfüzyon uyumsuzluğunun önemli bir göstergesi olan ölü boşluk üzerine etkisi yeterince araştırılmamıştır. Bu çalışmanın amacı, RM ve PEEP titrasyonunun ARDS’li hastalarda ölü boşluk üzerine etkisini değerlendirmektir. Gereç ve Yöntem: Bu prospektif gözlemsel çalışmaya erken evre ARDS tanısı almış on iki hasta dahil edilmiştir. Başlangıç stabilizasyonunun ardından, tüm hastalara standart bir RM protokolü uygulanmış ve ardından azalan PEEP titrasyonu gerçekleştirilmiştir. RM ve bireyselleştirilmiş PEEP titrasyonu öncesi ve sonrasında ölü boşluk parametreleri, akciğer mekaniği, kan gazları ve hemodinamik değişkenler ölçülmüştür. Bulgular: RM sonrasında hem hava yolu ölü boşluğu hem de fizyolojik ölü boşlukta istatistiksel olarak anlamlı bir azalma gözlenmiştir. PaO₂ ve oksijen satürasyonu artarken, arteriyel pH’ta hafif bir düşüş saptanmıştır. Alveoler ölü boşluk, kompliyans, hava yolu basınçları, son-tidal CO₂ ve hemodinamik parametrelerde ise anlamlı bir değişiklik izlenmemiştir. Sonuç: Erken dönem ARDS’de, RM’ler ve PEEP ile uygulanan bireyselleştirilmiş ventilasyon stratejileri, belirgin bir hemodinamik bozulmaya yol açmadan fizyolojik ölü boşluğu azaltabilir ve oksijenasyonu iyileştirebilir. Bu bulgular, gaz değişimini optimize etmeye yardımcı olmak ve klinik sonuçları potansiyel olarak iyileştirmek amacıyla, kişiselleştirilmiş yaklaşımlara ölü boşluk monitörizasyonunun dahil edilebileceğini düşündürmektedir.

Keywords

• Akut solunum sıkıntısı sendromu (ARDS)
• Ölü boşluk
• Recruitment manevrası
• PEEP
• Mekanik ventilasyon
• Solunum mekaniği
• Ventilasyon-Perfüzyon oranı

References

1. Ranieri VM, Rubenfeld GD, Thompson BT, Ferguson ND, Caldwell E, Fan E, et al. Acute respiratory distress syndrome: the Berlin Definition. JAMA. 2012; 307(23): 2526–33
2. Thompson BT, Chambers RC, Liu KD. Acute respiratory distress syndrome. N Engl J Med. 2017; 377(6): 562–72
3. Fan E, Brodie D, Slutsky AS. Acute respiratory distress syndrome: advances in diagnosis and treatment. JAMA. 2018; 319(7): 698–710
4. Matthay MA, Arabi Y, Arroliga AC, Bernard G, Bersten AD, Brochard LJ, et al. A new global definition of acute respiratory distress syndrome. Am J Respir Crit Care Med. 2024; 209(1): 37-47
5. Matthay MA, Zemans RL, Zimmerman GA, Arabi YM, Beitler JR, MercatA, et al. Acute respiratory distress syndrome. Nat Rev Dis Primers. 2019; 5(1): 18
6. Bellani G, Laffey JG, Pham T, Fan E, Brochard L, Esteban A, et al. Epidemiology, patterns of care, and mortality for patients with acute respiratory distress syndrome in intensive care units in 50 countries. JAMA. 2016; 315(8): 788–800
7. Acute Respiratory Distress Syndrome Network; Brower RG, Matthay MA, Morris A, Schoenfeld D, Thompson BT, Wheeler A. 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): 1301-8
8. Papazian L, Aubron C, Brochard L, Chiche JD, Combes A, Dreyfuss D, et al. Formal guidelines: management of acute respiratory distress syndrome. Ann Intensive Care. 2019; 9(1): 69

9. Fan E, Del Sorbo L, Goligher EC, Hodgson CL, Munshi L, Walkey AJ, et al. An Official American Thoracic Society/European Society of Intensive Care Medicine/Society of Critical Care Medicine Clinical Practice Guideline: Mechanical ventilation in adult patients with acute respiratory distress syndrome. Am J Respir Crit Care Med. 2017; 195(9): 1253–63
10. Santos RS, Silva PL, Pelosi P, Rocco PR. Recruitment maneuvers in acute respiratory distress syndrome: The safe way is the best way. World J Crit Care Med. 2015; 4(4): 278-86
11. Hess DR. Recruitment maneuvers and PEEP titration. Respir Care. 2015; 60(11): 1688-704
12. Enghoff, H. Volumen inefficax. Upsala Lakaref Forh 1938; 44: 191-218
13. Fowler WS. Lung function studies; the respiratory dead space. Am J Physiol. 1948; 154(3): 405-16
14. Fletcher R, Jonson B, Cumming G, Brew J. The concept of deadspace with special reference to the single breath test for carbon dioxide. Br J Anaesth. 1981; 53(1): 77-88
15. Nuckton TJ, Alonso JA, Kallet RH, Daniel BM, Pittet JF, Eisner MD, et al. Pulmonary dead-space fraction as a risk factor for death in the acute respiratory distress syndrome. N Engl J Med 2002; 346(17): 1281-6
16. Gattinoni L, Marini JJ, Pesenti A, Quintel M, Mancebo J, Brochard L. The ‘baby lung’ became an adult. Intensive Care Med. 2016; 42(5): 663–73
17. Meade MO, Cook DJ, Griffith LE, Hand LE, Lapinsky SE, Stewart TE, et al. A study of the physiologic responses to a lung recruitment maneuver in acute lung injury and acute respiratory distress syndrome. Respir Care. 2008; 53(11): 1441-9
18. Meade MO, Cook DJ, Guyatt GH, Slutsky AS, Arabi YM, Cooper DJ, et al. Ventilation strategy using low tidal volumes, recruitment maneuvers, and high positive end-expiratory pressure for acute lung injury and acute respiratory distress syndrome: A randomized controlled trial. JAMA. 2008; 299(6): 637-45
19. Kacmarek RM, Villar J, Sulemanji D, Montiel R, Ferrando C, Blanco J, et al. Open lung approach for the acute respiratory distress syndrome: A pilot, randomized controlled trial. Critical Care Medicine. 2016; 44(1): 32-42
20. Ferluga M, Lucangelo U, Blanch L. Dead space in acute respiratory distress syndrome. Ann Transl Med. 2018; 6(19): 388
21. Jayasimhan D, Chieng J, Kolbe J, Sidebotham DA. Dead-space ventilation indices and mortality in acute respiratory distress syndrome: A systematic review and meta-analysis. Crit Care Med. 2023; 51(10): 1363-72
22. Kallet RH, Zhuo H, Liu KD, Calfee CS, Matthay MA; National Heart Lung and Blood Institute ARDS Network Investigators. The association between physiologic dead-space fraction and mortality in subjects with ARDS enrolled in a prospective multi-center clinical trial. Respir Care. 2014; 59(11): 1611-8
23. Slobod D, Damia A, Leali M, Spinelli E, Mauri T. Pathophysiology and clinical meaning of ventilation-perfusion mismatch in the acute respiratory distress syndrome. Biology (Basel) 2022; 12(1): 67
24. Blanch L, Lucangelo U, Lopez-Aguilar J, Fernandez R, Romero PV. Volumetric capnography in patients with acute lung injury: effects of positive end-expiratory pressure. Eur Respir J. 1999; 13(5): 1048-54
25. Gogniat E, Ducrey M, Dianti J, Madorno M, Roux N, Midley A, et al. Dead space analysis at different levels of positive end-expiratory pressure in acute respiratory distress syndrome patients. J Crit Care. 2018; 45: 231-238
26. Kung S-C, Hung Y-L, Chen W-L, Wang C-M, Chang H-C, Liu W-L. Effects of stepwise lung recruitment maneuvers in patients with early acute respiratory distress syndrome: A prospective, randomized, controlled trial. J Clin Med. 2019; 8(2): 231
27. Cui Y, Cao R, Wang Y, Li G. Lung recruitment maneuvers for ARDS patients: A systematic review and meta-analysis. Respiration. 2020; 99(3): 264-276
28. Heunks L, Piquilloud L, Demoule A. How we approach titrating PEEP in patients with acute hypoxemic failure. Crit Care. 2023; 27(1): 415
29. Amato MB, Barbas CS, Medeiros DM, Magaldi RB, Schettino GP, Lorenzi-Filho G, et al. Effect of a protective-ventilation strategy on mortality in the acute respiratory distress syndrome. N Engl J Med. 1998; 338(6): 347-54
30. Hickling KG. Best compliance during a decremental, but not incremental, positive end-expiratory pressure trial is related to open-lung positive end-expiratory pressure: a mathematical model of acute respiratory distress syndrome lungs. Am J Respir Crit Care Med. 2001; 163(1): 69-78
31. Tusman G, Suarez-Sipmann F, Böhm SH, Pech T, Reissmann H, Meschino G, et al. Monitoring dead space during recruitment and PEEP titration in an experimental model. Intensive Care Med. 2006; 32(11): 1863-71