ARDS: The Evidence Todd M Bull MD Professor of Medicine Division of Pulmonary Sciences and Critical Care Division of Cardiology Director Pulmonary Vascular Disease Center Director Center for Lungs and Breathing University of Colorado, Denver A 42 year old female is admitted after a drug overdose complicated by emesis and aspiration. Intubation, mechanical ventilation initiated in the emergency department: AC, Vt 680, RR 10, FiO2 100%, PEEP 5. She weighs 68kg Ht 6 Vent mechanics include: PIP 52, Pplat 48, SpO2 86% ABG ph 7.38, PaCO2 36, PaO2 54, SpO2 86% Pa02/FI02 54/1 = 54 What interventions will improve this patients outcome A. Reduce tidal volume to 360 cc (6cc/kg) B. Early prone ventilation C. Diuresis when hemodynamically stable D. Early Neuromuscular blockade E. All of the above Topics New definition Breaths: Little or Big? Wet or Dry? Moving or Still? Upside down or Right side up?
ARDS Ashbaugh, Petty 1967 AECC 1994 (ARDS and ALI) ARDS and ALI AECC conference 1994 Acute onset CXR: Multiple lobe infiltrates Pa02/FI02 ratio < 300 ALI < 200 ARDS PCWP < 18 (presumed) Acute (7 days, most within 72 hrs) Bilateral opacities (CXR or CT) Do not need to exclude heart failure Not Explained by CHF Objective assessment (echo) if no clear trigger JAMA Vol 307 2012
ALI is out 3 Severity Categories: Hypoxia Pa02/FI02 1) mild: P/F 201-300 2) moderate: P/F 101-200 3) severe: P/F <= 100 ARDS Severity Berlin Definition PA02/FI02 Mild 200-300 27% Mortality Moderate 100-200 32% Severe < 100 45% What Works in ARDS? What are we trying to avoid???
Ventilator-induced lung injury (VILI) Ventilator induced lung injury 5 minutes Ventilator induced lung injury 20 minutes
ARDS: Little Breath or Big? Multicenter RCT 861 patients 6 cc/kg vs. 12 cc/kg (Ideal Body Weight) Pplat of 30 vs. 50 cm H20 New Eng J Med 2000; 342: 1301-1308. ARDSnet Study P =.007 39% 31% Mortality: 31% vs. 39% Days on Vent: 11 vs. 12 NNT = 11 New Eng J Med 2000; 342: 1301-1308.
Lung Protective Ventilation Controversies Implementation outside of tertiary hospitals in USA is poor 30% ARDS: Wet or Dry? FACTT n= 1000 pts ALI Randomized: Conservative vs. Liberal Fluid Balance Day 7-136 ml vs. 6992 ml NEJM 2006
1 - All cause mortality- day 60 25% vs. 28% p=0.3 2 - Vent Free days: 14 vs. 12 p<0.001 ICU Free day: 13 vs. 11 p< 0.001 NEJM 2006: FACTT ARDS: Moving or Still? N= 340 pts Severe ARDS P/F < 150 Randomized within 48 hours Cisatracurium vs. Placebo (Ramsey 6) Paralyzed for 48 hours NEJM 2010: ACURASYS
1 - HR 0.68 (0.4-0.9) 90 day mortality (p=0.04) 28 day mortality 23% vs. 33% p=0.05 No increase ICU paresis ARDS: Right side Up vs. Upside Down Prone Ventilation
Prone Ventilation in ARDS SUPINE Goal: Leverage nondependent, less involved lung parenchyma - ALI is regionally heterogeneous 1 Improves oxygenation short term PRONE But Nondependent lung will succumb to the perils of being dependent Randomized Clinical Trials 2-4 - Improves oxygenation (transient) - Does not appear harmful, easy to do - But.2 trials did not improve survival SUPINE AGAIN 1. AJRCCM 2001;164(1):131-40 2. NEJM 2001; 345(8):568-73 3. JAMA 2009;302(18):1977-84 4. JAMA 2004; 292;2379-87 NEJM 2001 JAMA 2009 n= 446 pts Enrolled by 36 hrs P/F ratio < 150 Proned : 16 hrs De-proned : 4 hours NEJM 2013 Proseva
1 - All cause mortality- day 28 16% vs. 32% p< 0.001 All cause mortality- day 90 23% vs. 41% No difference complications NNT = 6 High Frequency Oscillation
Extracorporeal Membrane Oxygenation (ECMO) A 42 year old female is admitted after a drug overdose complicated by emesis and aspiration. Intubation, mechanical ventilation initiated in the emergency department: AC, Vt 680, RR 10, FiO2 100%, PEEP 5. She weighs 68kg Ht 6 Vent mechanics include: PIP 52, Pplat 48, SpO2 86% ABG ph 7.38, PaCO2 36, PaO2 54, SpO2 86% Pa02/FI02 54/1 = 54 What interventions will improve this patients outcome A. Reduce tidal volume to 360 cc (6cc/kg) B. Early prone ventilation C. Diuresis when hemodynamically stable D. Early Neuromuscular blockade E. All of the above A 42 year old female is admitted after a drug overdose complicated by emesis and aspiration. Intubation, mechanical ventilation initiated in the emergency department: AC, Vt 680, RR 10, FiO2 100%, PEEP 5. She weighs 68kg Ht 6 Vent mechanics include: PIP 52, Pplat 48, SpO2 86% ABG ph 7.38, PaCO2 36, PaO2 54, SpO2 86% Pa02/FI02 54/1 = 54 What interventions will improve this patients outcome A. Reduce tidal volume to 360 cc (6cc/kg) B. Early prone ventilation C. Diuresis when hemodynamically stable D. Early Neuromuscular blockade E. All of the above
Thanks and Questions??