How ARDS should be treated in 2017

Transcription

1 How ARDS should be treated in , Ostrava Luciano Gattinoni, MD, FRCP Georg-August-Universität Göttingen Germany

2 ARDS 1. Keep the patient alive respiration circulation 2. Cure the disease leading to the syndrome 3. Don t add damage lung body 4. Provide the best environment for lung healing (???)

3 Aim of the respiratory support To buy time with minimal damage Damaging factors Lung Ventilator Baby lung size Homogeneity Recruitability Mechanical power

4 Small, inhomogeneous, recruitable lung VILI comes from

5 Acute Respiratory Distress Syndrome Timing Chest Imaging a Origin of Edema Within 1 week of a known clinical insult or new/worsening respiratory symptoms Bilateral opacities not fully explained by effusions, lobar/lung collapse, or nodules Respiratory failure not fully explained by cardiac failure or fluid overload; Need objective assessment (e.g., echocardiography) to exclude hydrostatic edema if no risk factor present Mild Moderate Severe 200<PaO 2 /FiO 2 < 300 Oxygenation b with PEEP or CPAP 5 cmh 2 O c 100<PaO 2 /FiO 2 <200 with PEEP 5 cmh 2 O PaO 2 /FiO2<100 with PEEP 5 cmh 2 O a Chest X-ray or CT Scan b If altitude higher than 1000m,correction factor should be made as follows: PaO 2 /FiO 2 x (barometric pressure/760) c This may be delivered non-invasively in the Mild ARDS group JAMA. 2012;307(23):doi: /jama

6 MILD MILD ARDS MODERATE P/F 160 P/F PEEP SEVERE PEEP P/F PEEP 5 cmh 2 O Clinical PEEP PEEP Caironi, et al. CCM 2015

7 Caironi, et al. CCM 2015

8 Baby lung

9 Gattinoni L et al. Intensive Care Med (1986) 12:

10 CT numbers frequency (%) Hyperinflated Baby Lung (1987) Normally aerated Poorly aerated Non aerated 50 Normal 40 ARDS CT numbers (Hounsfield Units)

11 Inhomogeneity

12 Voxel Vgas Gas fraction = V gas0 /V voxel Weighted gas ratio = V gas1 /V gas0 * fraction of tissue

13 Average ratio in normal subjects : 1.37±0.15 Healthy subject Moderate ARDS Severe ARDS

14 Ki/lung inhomogeneity interaction and gas/tissue composition MILD MODERATE SEVERE

15 Recruitability

16 Morphological response (1986) 5 cm H 2 O PaO 2 : 97 mm Hg 10 cm H 2 O PaO 2 : 103 mm Hg 15 cm H 2 O PaO 2 : 104 mm Hg d. 59% d. 56% 5 cm H 2 O 10 cm H 2 O PaO 2 : 34 mm Hg PaO 2 : 49 mm Hg d. 53% 15 cm H 2 O PaO 2 : 121 mm Hg d. 70% d. 52% d. 32% Intensive Care Med. 1986;12(3):

17 Opening pressures (2001) 6 dogs, Oleic acid % Potential for recruitment 100% inflation recruitment Airway pressure [cmh 2 O] Pelosi et al. Am J Respir Crit Care Med Jul 1;164(1):

18 Recruitment and inflation % 100 Inflation/Recruitment (2001) 5 patients, ALI / ARDS Potential for recruitment 5% Inflation % Recruitment % Paw [cmh 2 O] Crotti et al. Am J Respir Crit Care Med 2001;

19 Frequency [no. of patients] Figure 1 Potential for lung recruitment ± 4% (59 ± 51 grams) lower 21 ± 10% (374 ± 236 grams) higher ALI patients ARDS patients potential for lung recruitment [% total lung weight] Gattinoni L, Caironi P, Cressoni M, Chiumello D, Ranieri VM, Quintel M, Russo S, Cornejo R, Bugedo G, NEJM 2006, 354(17):

20 Recruited lung tissue (g) Opening Pressures Mild ARDS (N=5) Moderate ARDS (N=19) Severe ARDS (N=19) Plateu pressure limit Courtesy of dr. Cressoni M. Pressure (cmh 2 O)

21 Compartments (HU) -1000/ / / / / / / / /-100 0/-100 >0 A: TISSUE PEEP 5 PEEP 15 ** ** * Tissue (g) ** -1000/-900 ** -900/ / / / / / / /-100 0/-100 >0 ** B: GAS Gas (ml) ** ** Chiumello, et al. AJRCCM 2016

22 Aim of the respiratory support To buy time with minimal damage Damaging factors Lung Ventilator Baby lung size Homogeneity Recruitability Mechanical power

23 VILI comes from Excessive power

24 Time course of ventilator induced lung injury Lung Weight (g) Strain (Vt/FRC) Hours of mechanical ventilation 0.5 Protti A. et al. Am J Respir Crit Care Med Feb 4.

25 %Total Lung Capacity Resting Biotrauma Stress at rupture Strain Specific Lung Elastance 12 (cmh 2 O) Transpulmonary pressure (PL cmh 2 O) Agostoni, Mead, Weibel, Gattinoni

26 Stress-strain curve of healthy pigs Stress (PL, cmh2o) Specific Lung Elastance 5.8 cmh 2 O Strain (dvgas/vgas0) Protti A. et al. Am J Respir Crit Care Med Feb 4.

27 Lung Volume TLC FRC VT 100% V PEEP 0% VT 75% V PEEP 25% VT 50% V PEEP 50% VT 25% V PEEP 75% Protti et al. Crit Care Med Feb 4.

28 Mechanical ventilation and VILI 1.Volume 2.Pressure 3.Respiratory Rate 4.Flow 5.Or???

29 ZEEP 600 Total Inspiratory Volume Volume EXAPLES OF ENERGY COMPUTATIONS AT DIFFERENT PRESSURES 0 ZEEP Peak Pressure Pressure Total Inspiratory Volume LOW PEEP Total Inspiratory Volume HIGH PEEP PEEP Volume Volume 600 PEEP Volume Volume PEEP Peak Pressure 0 PEEP Peak Pressure Pressure Pressure

30 Motion equation Total pressure = (E rs V) + (R aw F) + PEEP Distend the lung Move the gas Keep open

31 Mechanical Power Total pressure V RR = Power rs = 0,098 RR V E rs + RR 1 + I: E 60 I: E R aw + V PEEP Distend the lung Move the gas Keep open TIME ENERGY

32 Percent increase power Contributions to Power generation 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% Baseline values RR 20 TV (L) 0,400 Ers 25 I:E 0,5 Raw 10 PEEP 10 Power rs 14,90 RR TV Peep Driving Press 0% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Percent increase variable

33 Summary TV Power 2 P aw Power 2 RR Power 1.6 PEEP Power 1

34 Interaction

35 Small, inhomogeneous, recruitable lung VILI comes from Excessive power

36 Chest wall elastance Stiff Soft Soft Stiff EL L Ew EL L Ew 25 5 cmh 2 O E tot E tot

37 Transpulmonary plateau pressue (cmh 2 O) Slope P L /P aw = E w /E tot [ ] A Surgical control group Medical control group B ALI patients ARDS patients Airway plateau pressure (cmh 2 O) Airway plateau pressure (cmh 2 O) Chiumello et al, Am J Respir Crit Care Med. 2008

38 Always consider: V T Baby lung size

39 The ARDS lung is small and not stiff Normal V T FRC = 500 ml 2500 ml = 0.2 ARDS V T FRC = 500 ml 500 ml = 1

40 Always consider: The lung inhomogeneity Stress raisers Atelectrauma

41 Lung expansion/gas-free state Mead J J Appl Physiol May;28(5): V 10 V V 1 V STRESS RAISER=(10/1) 2/3 = 4.64

42

43 Lung dishomogeneity and ARDS Mild (N=82) Moderate (N=71) Severe (N=12) P Dishomogeneity 1.49 ± ± ± Dishomogeneity 2/ ± ± ± 0.55 Extent 0.3 ± ± ± Intensity 2.69 ± ± ± Intensity 2/ ± ± ± 0.55 Am J Respir Crit Care Med Jan 15;189(2):149-58

44 Gas / Tissue Ratio The gas/tissue ratio as a function of lung height Normal Supine Normal Prone ARDS Supine ARDS Prone Lung Height (%) Gattinoni L et al. In: Tobin MJ (ed) New York

45 Guerin C. et al. N Engl J Med Jun 6;368(23): Gattinoni L. et al. Minerva Anestesiol Jun;76(6):448-54

46 Atelectrauma

47 Recruitment (g) Opening and closing (1995) Plateau Pressure (cmh 2 O) ± ± ± 1.8 End Expiration End Inspiration 38 ± ± ** ** ** PEEP (cmh 2 O) Gattinoni et al. Am J Respir Crit Care Med 1995;151:

48 Recruited tissue Recruitment-Pressure curve Opening-closing Exp. Exp Pressure

49 Lung protective strategy Less energy + More homogeneous lung