Conflict of Interest Disclosure Robert M Kacmarek Lung Protective Ventilation: New Information RT s Neec to Know 5-6-17 FOCUS Bob Kacmarek PhD, RRT Harvard Medical School Massachusetts General Hospital Boston, Massachusetts I disclose the following financial relationships with commercial entities that produce healthcare-related related products or services relevant to the content I am presenting: Company Relationship Content Area Medtronic Consultant Artificial Airways Medtronic Grant Mech Vent Orange Medical Consultant Mech Vent Teleflex Consultant Humidification Mechanical Ventilation 2016 State of the ART! Lung Protective Mechanical Ventilation Patient-Ventilator Synchrony ARDSnet NEJM 2000;342:1301 A V T of 6 ml/kg PBW results in a lower mortality than a V T of 12 ml/kg PBW Mortality 31% vs. 39.8% p = 0.0054 SCALING OF THE LUNG IN MAMMALS 100 10 SLOPE = 1.02 Dugong Manatee Bear Cow Pig Porpoise Goat MAN Whale Mortality vs Day 1 Plateau Pressure NIH Trial of 6 vs 12 ml/kg Tidal Volume L U M E, liter L U N G V O 1.1.01 Rat Racoon Cat Rabbit Marmot Guinea Pig Dog Monkey Armadillo Lung Volume = 6.3% BW Tidal Volume = 6.3 ml/kg Mouse.001 Shrew Bat.01.1 1 10 100 1000 Y T, B O D W E I G H kg Adapted from SM Tenney & JE Remmers, Nature 1963; 197:54-6; K Schmidt- Nielsen, 1972 Villar, Kacmarek, Hedenstierna. Acta Anaesth Scand 2004; 48:267-271. 271. 1
Gajic CCM 2004;32:1817 Plateau Pressure and V T Main risk factor for ALI large V T (OR 1.3 for ea ml above 6 ml/kg PBW p < 0.001 Transfusion blood products (OR 3.0, p<0.001) Acidemic ph < 7.35 (OR 2.0 p=0.32) End inspiratory over distension primary cause of VILI Transpulmonary pressure best indicator of over distension TPP = Pplat - Ppleural The best clinical indicator of TPP is plateau pressure not tidal volume Gajic CCM 2004;32:1817 Impact of Plat/V T on Mortality in ARDS P PLAT < 28 cmh 2 O, mortality reduced Lower the P PLAT, better the outcome RR limit based on autopeep, up to 40 or greater? P PLAT > 28 cmh 2 O, V T 4-5 ml/kg P PLAT 25 to 28 cmh 2 O, V T 6 ml/kg P PLAT < 25 cmh 2 O V T 6-8; if patient has a strong ventilatory demand, better to allow a little larger V T then to heavily sedate and force a very low V T! Kacmarek (Editorial) RC 2005;50:1624-16161616 In Severe Acute Hypoxemic Respiratory Failure Tidal Volumes MUST be Maintained between 4 to 6 m/kg PBW or lower to insure Plateau Pressures do not exceed 28 cm H 2O Permissive Hypercapnia is generally the rule Acceptable ph > 7.15 ARDSnet NEJM 2000;342:1301 2
Amato NEJM 2015;372:747-755. Multi-regression analysis of 9 RCT on ARDS: Variable V T and Variable PEEP Tidal volume not the primary variable associated with mortality Plateau pressure not the primary variable associated with mortality PEEP not the primary variable associated with mortality Driving Pressure (DP) on day of enrollment into the studied RCT s the primary variable associated with mortality!!! DP = Plateau Pressure PEEP Amato NEJM 2015;372:747-755 Amato NEJM 2015;372:747-755 Management of ARDS (All Patients) Tidal Volume 4 to 8 ml/kg PBW the greater the plateau pressure the lower should be the V T Plateau Pressure < 28 cmh 2 O Stiff chest wall greater force on the thorax MAY BE able to tolerate a high Pplat Driving pressure <15 cmh 2 O, the lower the DP the better PEEP appropriate for the patient presentation Method of Setting PEEP Level PEEP/F I O 2 Table Transpulmonary pressure/f I O 2 Table Brochard/Mercat method Stress Index P V curve Incremental PEEP trial Decremental PEEP trial End Expiratory Transpulmonary Pressure End expiratory esophageal pressure used to determine the setting of PEEP TPP = PEEP -Pes -3 cmh 2 O = 5 cmh 2 O (-8 cmh 2 O) TPP = PEEP -Pes 2 cmh 2 O = 10 cmh 2 O (-8 cmh 2 O) 3
Talmor NEJM 2008;359:2095 PRO Single study good outcome data Based on the pts lung mechanics CON Requires placement of esophageal catheter Difficult to position and maintain position Question reflection of pleural pressure Needs more study Arbitrary in its scaling Pirrone et al CCM 2016(2);44: 300 Suarez-Sipmann Sipmann CCM 2007;35:214 Pirrone et al CCM 2016(2);44:300 TPP = - 4 cmh2o TPP = +1 cmh2o 4
Pirrone et al CCM 2016(2);44:300 Pirrone et al CCM 2016(2);44:300 Pirrone et al CCM 2016(2);44:300 Pirrone et al CCM 2016(2);44:300 Kacmarek et al CCM 2016(1);44:32 Open lung approach (OLA) vs. ARDSnet PIP, Pplat and driving pressure all higher in ARDSnet PEEP approximately 5 cmh 2 O higher in OLA FIO 2 lower, PaO 2 higher, P/F higher, V T lower, RR higher, PCO 2 higher (day 1) in OLA No difference pneumothorax, cardiac arrest, hypotension, desaturation, arrhythmias Kacmarek et al CCM 2016(1);44:32 5
Guerin NEJM 2013;May 20 th, 2013 Types of Asynchrony Flow asynchrony Inadequate flow at onset of inspiration to meet patient demand Trigger asynchrony Poor coordination of patients initiation of inspiration and ventilator response Trigger delay Double trigger Missed trigger Auto trigger; entrainment/reverse triggering Cycling asynchrony Poor coordination of patients desire to exhale and ventilator response Inappropriately short inspiratory time Inappropriately long inspiratory time Mode Asynchrony Inappropriate mode Variables Controlled during Mechanical Ventilation Pressure, Flow, Volume and Time Volume Assist/Control Volume Flow Time Pressure Assist/Control Pressure Time Pressure Support Pressure PAV and NAVA None Younes ARRD 1992;145:114 Thille ICM 2006;32:1515 62 consecutive pts, MV > 24 hrs, 11 VA/C, 51 PS Median episodes/pt VA/C 72 (13-215), PS 16 (4-47)/ 30 minute period, p=0.04 A higher incidence of asynchrony was associated with a longer period of MV 25.5 5 vs. 7.5 days De Wit CCM 2009;37:2740 60 consecutive pts, MV > 24 hrs, 10 min during the 1 st 24 hours were analyzed 16 patients an asynchrony index >10% AI >10% predicted longer LOS (21 vs. 8 days p < 0.03) Mellott 2015;191:A3897 Texas, Virgina Flordia, Georgia 30 pts 79 min (range 53-92) recording of flow/press waveforms and video recording Asynchrony present in 23% of breaths Altered respiratory dynamics, accessory muscle use, altered breathing patterns associated with asynchrony Facial grimace, extremity movement associated with asynchrony 6
J Neurophysiol 2002;88:1500-1511 Neurophysiologic Model of Respiratory Discomfort: Air Hunger Work/Effort Tightness O Donnell DE et al Resp Physiol Neurobiol 2009 Air Hunger Increases MRI Signal in Insula (Limbic System) Insula Insula (Limbic System): -Perception of dyspnea, hunger, thirst -Afferents of resp. chemoreceptors -Stretch receptors project to insula -Seat of emotions -Large role in memory Air hunger causes severe psychological trauma Sottile AJRCCM 2015;191:A3894 Columbia University NY N=11, 6 early ARDS <12 hrs MV, VA/C 72 hr continuous measurement of flow/press Dt Determined ddouble triggering ti i (DT) and dflow limited (FL)(NOT defined) V T set 6.6+0.6 ml/kg PBW 5% of breaths DT and 11.7% FL Beitler, Talmor AJRCCM 2015;191:A3896 20 early ARDS, <24 hrs MV 72 hr continuous measurement of flow/press Determined double triggering (DT) defined as V T > 2ml/kg PBW over set V T Setting VA/C, V T 67+1 6.7+1.0 ml/kg PBW, RR 25+5/min, T I 0.8+0.1 sec DT all, 0.1 to 89.6% of breaths, median 6.0% (1.3 15.9%) In 40% of pts >10% double triggering. DT survivors (15) < non survivors (5) 3.7% (0.6 9.7) vs.19% (11-76) p=0.036 50 patients, 7,027 hrs MV, 8,731,981 breaths Better Care TM Evaluated asynchrony Ineffective efforts during expiration (IEE) Double Triggering (DT) Short cycling < 50% mean inspir time (SC) Prolonged cycling > 100% mean inspir time (PC) Asynchrony index (AI) Air trapping Secretions Plateau pressure Mode of Ventilation 7
Lung Protective Ventilation! All patients ventilated with LPV: V T 4-8 lm/kg, Pplat <28 cmh 2 O, Driving pressure <15 cmh 2 O Set appropriate for the patients condition Recruit the lung Set PEEP; End Expiratory TPP or Decremental PEEP trial Asynchrony occurs in ALL patients actively interacting with the ventilator It can have a profound affect on patient outcome Should be evaluated and assessed during every patient ventilator interaction Thank You 8