Recruitment Maneuvers in ARDS Dr Chennamchetty Vijay Kumar
57 likes11,187 views
This document discusses recruitment maneuvers for mechanically ventilated patients. It begins with a case study of a patient presenting with respiratory failure. It then provides definitions and the physiological rationale for recruitment maneuvers, including how alveolar collapse occurs in ARDS. Different types of recruitment maneuvers are described, as well as factors that influence their effectiveness. Clinical trials on recruitment maneuvers are summarized, which found no significant reduction in mortality but some improvement in secondary outcomes. Limitations of recruitment maneuvers are discussed, such as potential hemodynamic effects. The document concludes with emphasizing the complexity of lung recruitment and ongoing controversies regarding recruitment maneuvers.
![Opening and Closing Pressures
50
Paw [cmH2O]
0 5 10 15 20 25 30 35 40 45 50
0
10
20
30
40
Opening
pressure
Closing
pressure
“High pressures may be needed to open some lung units,
but once open, many units stay open at lower pressure”
%
Crotti et al
AJRCCM 2001](https://image.slidesharecdn.com/recruitmentinardsdrchennam-101124143922-phpapp02/85/Recruitment-Maneuvers-in-ARDS-Dr-Chennamchetty-Vijay-Kumar-12-320.jpg)
Recruitment Maneuvers in ARDS Dr Chennamchetty Vijay Kumar
- 1. Recruitment Maneuvers Dr. Vijay Kumar Chennamchetty
- 2. Case Scenario A 23yr female student by occupation presented with febrile illness of 4days, h/o sore throat, cough present, no h/o travel, h/o breathlessness 1day o/e Sensorium normal Lungs: rr-40/mt, Spo2: 55% on NRBM Hemodynamics: stable ABG: type 1 resp failure (po2=25) Intubated in EMR & shifted to CCU
- 4. Recruitment Maneuvers Introduction Definition Physiological Rationale Recruitment Maneuvers (RM’s) Monitoring The Efficacy Factors Influencing The Response Clinical Trials Limitations
- 5. Introduction Mechanical Ventilation as an essential supportive measure “Lung protective” approach DrawbackARDS work. NEJM 0; 342:1301-08 Gajic et al VALI in pt’s with no lung ALI . CCM 2004; 32:1817-24
- 7. Definition Recruitment: “ aeration of un-aerated alveoli” Recruitment Maneuver / Re-expansion Maneuver: “ denotes the dynamic process of an intentional transient increase in trans pulmonary pressure aimed at opening unstable airless alveoli leading to increase in EELV, even if it is inadequate to result in effective alveolar recruitment ” Pelosi et al, Review article Critical Care 2010; p1 - 7
- 9. ARDS: Physiological Rationale Baby lung 1. Normal 2. Partly aerated 3. Collapsed 1. Lung protection 2. Alveolar stabilization 3. Alveolar recruitment Gattinoni et al. Intens Care Med. 1986; 12: 137-42
- 10. Physiological Rationale Atelectasis in normal lungs Absorption atelectasis Surfactant depletion “Lung protective strategy” RACE - Biotrauma Froesse JC Anesthesiology 1974; 41:242-55 Maggiore et al AJRCCM 2003; 167:1215-24 Ranieri et al A RCT JAMA 1999; 282:54 - 61 Over-distension Atelectasis
- 11. End-Expiration Tidal Forces (Transpulmonary and Microvascular Pressures) Extreme Stress/Strain Moderate Stress/Strain Mechano signaling via integrins, cytoskeleton, ion channels inflammatory cascade Cellular Infiltration and Systemic Inflammation Rupture Signaling Pathways to VILI Marini / Gattinoni CCM 2004 Barotrauma Volutrauma Biotrauma Stress @ interface MODS Slutsky et al Chest, 116 (1): 9s-16s RACE
- 12. Opening and Closing Pressures 50 Paw [cmH2O] 0 5 10 15 20 25 30 35 40 45 50 0 10 20 30 40 Opening pressure Closing pressure “High pressures may be needed to open some lung units, but once open, many units stay open at lower pressure” % Crotti et al AJRCCM 2001
- 14. Who needs RM ……… ARDS Hypoxic Post suctioning Post disconnection Atelectasis related to GA Cardiogenic Pulmonary EdemaLapinsky & Sangeeta Mehta Critical Care 2005; 9:60 - 65
- 15. Recruitment Maneuvers Introduction Definition Physiological Rationale Indications Types of Recruitment Maneuvers
- 16. Pre-requisites to perform RM Arterial line Central line Deep Sedation / Paralysis Alarm settings
- 17. Recruitment Maneuvers “Continuous inflation” technique Anesthesiology 2002, 96:795–802. Curr Opin Crit Care 2003; 9:22–27 CPAP : 35-40 cm H20 for 30-40 seconds
- 18. Continuous Inflation Technique CPAP 40cm for 40 secs PEEP set 2cm above LIP Borges et al Critical Care 2002; 9:60 - 65 % Collapsed lung Recruitment Steps 63% 05%
- 19. Continuous Inflation Technique Anesthesiology 2002, 96:795–802. Curr Opin Crit Care 2003; 9:22–27 PEEP + Peak pressure: up to 60 cmH2O
- 20. Recruitment Maneuvers Anesthesiology 2002, 96:795–802. Curr Opin Crit Care 2003; 9:22–27 Crit Care Med 2004; 32: 2371–77 Intermittent Sigh Intermittent PEEP Progressive PEEP Slide Courtesy: Dr. Ram Echambadi Rajagopalan
- 21. Anatomical Recruitment No recruitment PEEP + 5 40 cm recruitment + PEEP above LIP 60 cm recruitment PEEP + 25AJRCCM 2006;174: 268 – 78. 26 patients Slide Courtesy: Dr. Ram Echambadi Rajagopalan
- 22. Recruitment Maneuvers Introduction Definition Physiological Rationale Indications Recruitment Maneuvers Monitoring The Efficacy
- 23. Monitoring The Efficacy Malbouisson et al PEEP-RM / CT AJRCCM 2001; 163:1444-50 Richard JC et al Role of PEEP & RM AJRCCM 2001; 163:1609-13 Enrique & Vilagra Effects of RM CC Forum 2004; 8:115-121 ATS loop C: Sustained inflation on high PEEP favored alveolar over-distension
- 24. Interpreting the PV Curve Measurement is not practical clinically A single inflation probably does not provide useful information to determine safe ventilator settings Whole lung P/V curve is a composite of multiple regional P/V curves (LIP varies widely) Kunst PW et al CCM 2000
- 25. PaO2 improves No change EVLW Decrease in atelectasis rather than EVLW Change in CI - Significant Continuous Scvo2 Changes in CVP, HR & MAP - insignificant Tamas Leiner et al CCM 2007; Vol 35, No.3 n = 18
- 26. Viviane R. S, MD ;et al CCM 2010; Vol. 38, No 11 n = 36 40 cm/40secAnaesthesia, NMB & Protective Ventilation ABG & Lung mechanics ABG & Lung mechanics
- 27. After RM, Static lung elastance & alveolar collapse lung, liver, and kidney cell apoptosis, and type 3 pro-collagen and interleukin-6 mRNA expressions Electron microscopic images of lung parenchyma were assessed Alveolar edema is seen only in severe ALI Alveolar collapse were similar in both ALI groups Viviane R. Santiago, MD ;et al CCM 2010; Vol. 38, No 11
- 28. Conclusions RM seems to promote modest but consistent increase alveolar stress & inflammation fibrogenic responses worsening lung function & potentiating injury to alveolar and kidney epithelium lower in moderate ALI than in severe ALI IL-6 Type 3 Collagen
- 29. Recruitment Maneuvers Introduction Definition Physiological Rationale Indications Recruitment Maneuvers Monitoring The Efficacy Factors Influencing The Response
- 30. Factors Influencing The Response Non uniformity & Variable outcome Underlying lung disease Baseline ventilation & volume history Duration of Illness Prone position Type of RM & Post-recruitment PEEP
- 31. Underlying lung disease Douglas R.Riva et al CCM 2008; Vol.36 163:1900-08 Malbouisson et al PEEP-RM / CT AJRCCM 2001; 163:1444-50 “more effective at opening collapsed alveoli in extra- pulmonary ARDS, thus improving lung mechanics, oxygenation, with limited damage to alveolar epithelium”
- 32. Underlying lung disease Douglas R.Riva et al CCM 2008; Vol.36 163:1900-08 Malbouisson et al PEEP-RM / CT AJRCCM 2001; 163:1444-50 “greater PCIII mRNA expression in ALI pulmonary” RILI
- 33. Baseline ventilation & “Volume history” Proportion of atelectatic lung Ventilatory settings that promote derecruitment Volume history: time dependant manner Bates JH et al Time dependency; Theoritical model Journal of Physiology 2002 Vander Kloot et al RM in oleic acid injury model AJRCCM 2000; 161:1949-56
- 34. Duration of Illness “Less is More” & “More is Less” Less compliance of Lung & Chest wall Grasso S et al Anesthesiology 2002; 96: 795-802
- 35. Prone position RM by itself “Mule” or Complimentory effect No incerase in EELV Makes lung expansion more uniform by the attenuation of heterogeneous compressive forces Pelosi et al AJRCCM 2003; 167: 521-527
- 36. RM type & Post-RM PEEP Evidence little for type of RM Animal experiments Pressure targeted appears promising Post recruitment PEEP level – most important determinant to prevent RACE Lim et al CCM 2003; 167: 521-527
- 37. Recruitment Maneuvers Introduction Definition Physiological Rationale Indications Recruitment Maneuvers Monitoring The Efficacy Factors Influencing The Response Clinical Trials
- 38. EXPRESS TRIAL A RCT : JAMA 2008 768 patients, RCT Minimal distension: PEEP & Plat : as low as possible Without affecting saturation targets Increased Recruitment group: “PEEP titration based on Plateau” Oxygenation is not the goal L. Brochard
- 39. EXPRESS TRIAL A RCT : JAMA 2008 Conclusion: “strategy aimed at increased alveolar recruitment while limiting hyperinflation didn’t significantly reduced mortality” Better lung mechanics Reduced duration of MV Reduced duration of organ failure Post hoc analysis: “ ALI may be associated with less benefits & more adverse effects from high levels of PEEP” L. Brochard
- 40. Lung Open Ventilation Study JAMA 2008 985 pts enrolled, RCT Control group: protective ventilation Volume Control Experimental group: PC mode + RM (40/40) + Pplat 40 Tidal volumes were similar Mean PEEP : 10 Vs 15 in first 72hrs Barotrauma rates were similar
- 41. Lung Open Ventilation Study JAMA 2008 Conclusion: “open strategy did appear to improve secondary end points related to hypoxemia & use of rescue therapies” Low rates of Refractory hypoxemia, Death with refractory hypoxemia & Need of “Rescue therapy”
- 42. Recruitment Maneuvers Introduction Definition Physiological Rationale Indications Recruitment Maneuvers Monitoring The Efficacy Factors Influencing The Response Clinical Trials Limitations
- 43. Limitations Brower, et al.: RMs in ALI Review article AJRCCM 2008; 176: 521-527
- 44. In a nut shell………. Hemodynamic compromise Intracranial blood flow VILI / RILI Bacterial translocation Clinical benefits ????
- 45. Hemodynamic Effects Lung inflation by positive pressure causes Increased pleural pressure and impeded venous return Increased pulmonary vascular resistance Compression of the inferior vena cava Retardation of heart rate increases These effects are much less obvious in the presence of Adequate circulating volume Adequate vascular tone Spontaneous breathing efforts Preserved adrenergic responsiveness
- 46. “With More Lung Compliance, High Levels of PEEP are Generally Not Well Tolerated” Hemodynamic Effects
- 47. Capillaries in the alveolar walls undergo compression even as interstitial vessels dilate. The net result is usually an increase in pulmonary vascular resistance, unless recruitment of collapsed units occurs. Hemodynamic Effects On Pulmonary vasculature:
- 48. Recruitment Maneuvers Introduction Definition Physiological Rationale Recruitment Maneuvers Monitoring The Efficacy Factors Influencing The Response Limitations Summary
- 49. Summary……….. Transient increase in trans pulmonary pressure to increase in EELV “Lung protective strategy” Bio-trauma facilitates MODS ARDS – commonest indication Prerequisites CPAP – most widely studied & PEEP titration in PC mode is user & hemodynamic friendly
- 50. Summary……….. Pao2 is a surrogate marker for monitoring Continuous Scvo2 & CCO monitor is recommended as CVP is poor predictor of CI RM worsens the inflammation in Pulmonary ALI Volume history is important before attempting a RM Prone has complimentary effect Titrate PEEP based on compliance & oxygenation
- 51. Summary……….. Studies Did not reveal any mortality benefits Did appear to improve secondary end points & its role as rescue therapy Adverse events Hypotension & Arrhythmias Barotraumas & De-saturation
- 52. Controversies Which patients will benefit? How long to recruit? What is optimum level of Post recruitment PEEP? When to use: routine or only during hypoxic episodes?
- 53. Thank u so…… much
- 54. Diseased Lungs Do Not Fully Collapse, Despite Tension Pneumothorax …and They cannot always be fully “opened” Dimensions of a fully Collapsed Normal Lung
Editor's Notes
- #2: Just recollect my memories, when I was working at SMF
- #5: 1. Through out the presentation, I will be mentioning RM as RM
- #8: An aim to increase EELV
- #11: Froesse: Effects of anesthesia & paralysis on diaphragmatic mowements in man. Tendency of caudobasal segmental collapse ewen in normal lungs in periop period. Maggaire: prewention of ET-suction induced alweolar derecruitment in ALI. Repaeted ET Suctioning & high fi02 requirements- commonly seen in wentilated patients – promote absorption atelectasis. Ranieri: effect of MW on inflammatory mediators in pts with ARDS, A RCT. Rimsenberger (Not mentioned abowe), Open lung during small tidalwolume wentilation : concepts of optimal peep & recruitment CCM 1999. He stated clearly that, “As the lewel of applied peep to keep recruited lung open may be lower than that required to open up atelectatic segments”.
- #12: Definitions: Stress: During MV, spatial rearrangement if fibres occurs due to Trans-pulmonary pressure. Strain: During MW, elongation of fibres leads to dewelopment of strain. These fibres hawe a wariable capacity to elongate & when stress exceeds the capacoty of the fibres to stretch, the fibres rupture leading to Baro trauma. Volutrauma occurs when strain is not high enough to rupture the fibres. B. MSOF is the result Tissue injury secondary to inflammatory cells/mediators Impaired oxygen deliwery ??? Bacteremia
- #19: 1.% of collapsed tissue decreased from 63% at ZEEP to 29% after open lung approach & after RM to 5%. 2. Simillarly P/F increased from 92% (ZEEP) to 250 (after open lung approach) & after RM to 400. Computed tomography quantification of collapsed tissue and PaO2/FIO2 ratio obtained with different recruitment maneuvers in acute respiratory distress syndrome patients. PPLAT, plateau pressure; ZEEP, zero end-expiratory pressure. From Borges (33)
- #24: P/F Ratio from ATS. There are studies where they studied, role of Paco2 and dead space assessment as a measure of recruitment. Malbouisson et al, “ CT assessment of PEEP induced Alveolar Recruitment”, showed a significant correlation bwn PEEP induced RM and improwed arterial oxygenation when recruitment was assessed by the volume of gas entering nonaerated or poorly aerated areas of the lung as seen on CT scans. Richard et al : “ Influence of tidal volume on Alv Recruitment: Respective role of PEEP & a RM”. Upward shift of the Static PV curve as well as chest wall & lung elastance Dynamic loops during three modes of ventilation inscribed into the quasistatic pressure–volume curve of the respiratory system of an animal after lung washes. Loop A: tidal insuflation with a positive endexpiratory pressure (PEEP) below the lower inflection point before a sustained inflation. Loop B: tidal insuflation with a PEEP below the lower inflection point after a sustained inflation. Loop C: PEEP higher than the lower inflection point after a sustained inflation. Sustained inflation promoted alveolar recruitment at low PEEP levels (loop B). Sustained inflation superimposed on high PEEP favored alveolar overdistension in this model of surfactant depletion (loop C).
- #27: Paraquat model ws saline intraperitoneally Single RM CPAP PS 40/40 f/b 1hr protectiwe wentilation. Apologies for B&W pictures instead of H&E stained Electron microscopic images of lung parenchyma in control and in moderate and severe acute lung injury groups with recruitment maneuver or not (nonrecruited). Moderate acute lung injury showed cytoplasmatic degeneration of type 2 pneumocytes and endothelial injury, whereas in severe acute lung injury alveolar epithelium and endothelium presented further damage. In the control–nonrecruited group, type 2 cells were well preserved, with typical microvilli projecting from the surface. Note the integrity of the alveolar capillary membrane. A recruitment maneuver led to the detachment of alveolar epithelium in moderate acute lung injury (ellipse), which was more pronounced in severe acute lung injury (arrows).
- #28: Apologies for B&W pictures instead of H&E stained Electron microscopic images of lung parenchyma in control and in moderate and severe acute lung injury groups with recruitment maneuver or not (nonrecruited). Moderate acute lung injury showed cytoplasmatic degeneration of type 2 pneumocytes and endothelial injury, whereas in severe acute lung injury alveolar epithelium and endothelium presented further damage. In the control–nonrecruited group, type 2 cells were well preserved, with typical microvilli projecting from the surface. Note the integrity of the alveolar capillary membrane. A recruitment maneuver led to the detachment of alveolar epithelium in moderate acute lung injury (ellipse), which was more pronounced in severe acute lung injury (arrows).
- #29: Real-time polymerase chain reaction analysis of interleukin-6 and type 3 procollagen mRNA expressions of rat lung tissue in control and in moderate and severe acute lung injury groups with recruitment maneuver or not (nonrecruited).
- #31: There was an initial enthusiasm for benefits of RMs, but studies indicated that the improvement of oxygenation & duration of benefit are widely variable.
- #33: RMs are more effective at opening collapsed alveoli in an experimental model of ALIexp than in ALIp, thus improving lung mechanics and oxygenation, with limited damage to alveolar epithelium.
- #34: Pt managed with went settings that promote derecruitment will respond fawourably by increasing EELW & oxygenation after a RM. This is clearly indicated wander klloot study. They were unable to demonstrate benefits from a RM in animals wentilated with a PEEP of 20cms & a tidal wolume of 15ml/kg in contrast with lower PEEP and tidal wolume. This suggest that the a.w. pressures in the former group are sufficiently high enough recruit most recruitable lung units & we cant expect additional benefit from RM. Wolume H/O: Low WT & Low PEEP cause collapse of the a.w. in a time dependent manner. Its imp to recognise that mechanics of the lung is not only influenced by the wolume of gas in it or the pettern of flow of gas, but also how this lung wolume has been alterd ower a period of time.
- #36: Both animal studies & studies in ARDS patients reweals, RMs are more effectiwe in Prone position. Pelosi study : An Intermittent sigh was noted to transiently open up collapsed units as indicated by some improwement of oxygenation & a small increase EELW in supine pt. When they repeated RMS in prone patient, significant increase in oxygenation & EELW. Conclusion: They work together, PP & RM hawe a complimentary action as they work by different mechanisms. i.e.a. Prone: no incease in EELW, makes lung expansion more uniform by the attenuation of heterogenous compressiwe forces
- #37: Lim et al compared bwn PC (45/16) RM / CPAP (45 for 40sec) & Incremental PEEP (upto 35cms maintaining Ppeak <35cms H20) in animals with VILI & they observed best response in PC RM. The emphasis of the study was however that the most imp determinant of efficacy was the level of post Rec PEEP applied to Pv RACE
- #40: Rewerse trend obserwed in ARDS from low lewels of PEEP
- #44: Total 248 articles awailable online.
- #53: Which pts will benefit whether Pulm ARDS or EP ARDS