flow (L/min) PSV. pressure (cm H 2 O) trigger. volume (ml)

Size: px

Start display at page:

Download "flow (L/min) PSV. pressure (cm H 2 O) trigger. volume (ml)"

Jeremy Newman
6 years ago
Views:

Invasive Mechanical Ventilation 6-9-08 Estonia Robert M Kacmarek PhD, RRT Massachusetts General

Tidal Volume Variable Constant Peak Alv Press Peak Air Press Flow Pattern Peak Flow Inspir Time

1 Invasive Mechanical Ventilation Estonia Robert M Kacmarek PhD, RRT Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts Pressure vs Volume Ventilation Pressure Volume Tidal Volume Variable Constant Peak Alv Press Peak Air Press Flow Pattern Peak Flow Inspir Time Minimum Rate Constant Constant Variable Variable Decelerating Preset Variable Preset Preset Constant Preset Preset 1

Pressure control preferred (In My Opinion) over Volume High ventilatory

2 Assist/Control Basic mode of ventilatory support Provides control of a number of ventilatory variables Primary approach for all critically ill Pressure control preferred (In My Opinion) over Volume High ventilatory demand Varying ventilatory demand Variable tidal volume acceptable Marini ARRD 1986;134:902 2

3 Fernandez ARRCCM 1999;159:710 PS vs. PA/C PS PA/C Pressure level Set Set Inspiratory Time Pt controlled Set Rate Pt controlled Back up Set Gas Delivery Pattern the Same for both Modes 3

4 Pressure Support Provides little control over ventilation Only factor controlled is peak pressure Useful during initial support or following the most acute stage of ventilatory support Commonly used mode of ventilation flow (L/min) pressure (cm H 2 O) trigger PSV volume (ml) 4

5 Fabry Chest 1995:107: PSV: Primary Variables Affecting Synchrony Rise Time Inspiratory Cycling Criteria (Inspiratory Termination Criteria) Pressure Support Level 5

6 Hess RC 2005:50:166 MacIntyre Chest 1991:99:134 6

7 Branson, Campbell RC 1998;43:1045 Parthasarathy AJRCCM 1998;159:1023 7

8 PSV: Termination of Inspiration Primary method: Patients Inspiratory Flow Decreases to a Predetermined Level % of Peak Inspiratory Flow, Usually 25% Some low flow 5 LPM or 5% of Peak Flow Other newer ventilators Variable termination criteria From 5% to 85% PSV: Termination of Inspiration Secondary Termination Criteria: End Inspiratory Pressure exceeds Target Level Tertiary Termination Criteria: Lengthy Inspiratory Time ( 2 to 3 Sec) 8

9 Hess RC 2005:50:166 Inappropriate PSV or PA/C Level To low a pressure level increases patient demand increasing patient work To high a level causes dysynchrony: forced exhalation, air trapping and increased ventilatory demand Frequently, decreasing PSV or PA/C level may be the correct choice 9

10 pressur re A SIMV B assist window time pressure (cm H 2 O) flow (L/min) SIMV spontaneous breath mandatory breath volume (ml) 10

11 Marini ARRD 1988: ; Imsand Anes 1994;80:

12 Kapasi Ped CCM 2001;2:9 PRVC and VS Pressure regulated volume control and Volume support Both target a preset V T and adjust the level of pressure ventilation (1 to 3 cmh 2 O) as needed to ensure the delivery of the V T PRVC - set rate, inspiratory time, V T and pressure limit VS -set V T and pressure limit Test breath calculates pressure needed to deliver V T 12

13 PRVC/VS Two randomized weaning trials Piotrowski ICM 1997;23:975 PRVC vs. IMV neonates PRVC weaned faster and greater IVH with IMV Randolph JAMA 2002; : VS vs. PS with protocol vs. PS without protocol pediatric patients No diff in time to wean or wean rate Jabar ICM 2005;31:

14 Invasive MV -COPD Primary Concerns; Pt-Vent interaction synchrony Inspiratory time short End inspiratory flow high Air trapping and auto PEEP Tidal volume small Ideally long expiratory time, slow rate Pepi ARRD 1982;126:166 14

15 Fabry Chest 1995;107:1387 Auto-PEEP Work of Breathing Alveolar Pressure +10 cmh 2 O Airway Pressure Trigger Pressure 0 cmh 2 O -2 cmh 2 O Patient Pressure change -12 cmh 2 O needed to trigger 15

16 PEEP Aplication Gottfried SB, Ventilatory Failure (Spring-Verlag),1991 Smith JAP 1988;65:

17 PEEP Assisted Ventilation COPD If auto-peep measured, set PEEP at 80% of measured level If auto-peep unmeasured, set PEEP at 5 cmh 2 0 If untriggered breathes still present, increase PEEP in 1 to 2 cmh 2 O steps until patient rate and ventilator response rate are equal Invasive MV ALI/ARDS Prevent further lung injury Low transpulmonary pressure Plateau pressure < 30 cmh 2 O, ideally < 25 Tidal volume 4-8 ml/kg PBW Avoid trying to normalize blood gases PO mmhg PCO 2 - permissive hypercapnia if necessary ph > 7.15 Maintain patient-ventilator synchrony 17

18 ARDSnet NEJM 2000; :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 =

19 Petrucci, Iacovelli Meta-analysis analysis Small V T Cochrane Database 2003:3 All Five previous trials 1202 patients Lower V T associated with decreased mortality 216/ (35.7%) vs. 249/597 (41.7%) p< Relative risk 0.85 (CI 0.74 to 0.98) However if the plateau pressure was < 31 cmh 2 O no significant difference between the use of a low and high V T Relative risk (CI 0.88 to 1.45) Deans CCM 2007;35 35:1509 Reanalysis of the ARDSnet Hi/Low V T and Canadian Blood Transfusion TRICC trials Practice Misalignment a prerandomizaton relationship between a dose and a patient related variable: Severity of illness, age, presence of ischemic heart disease and need for transfusion Compliance, plateau pressure and the application of a small or large V T 19

20 Deans CCM 2007;35 35:1509 Prerandomization compliance > 0.6 ml/cmh 2 O/Kg randomized to hi/low V T Low V T 37% vs. Hi V T 21% mortality Prerandomization compliance < 0.6 ml/cmh 2 O/Kg randomized to hi/low V T Low V T 29% vs. Hi V T 42% mortality P < RCT Non ALI Small vs. Large V T No Significant Difference Between Groups! Wrigge ICM 2005;31 31: Post Cardiopulmonary Bypass, 6 vs. 12 ml/kg Wrigge Anesth Analg 2004;98 98:775 Major thoracic or abdominal surgery, ml/kg, no PEEP vs. 6 ml/kg, 10 PEEP Koner ICM 2004;50 50:620 Ventilation during open heart surgery, 6 ml/kg, 5 PEEP vs. 10 ml/kg, 5 PEEP vs. 10 ml/kg, zero PEEP Wrigge Anes 200;93 93:1413 General surgery, 15 ml/kg, zero PEEP vs. 6 ml/kg, zero PEEP vs. 6 ml/kg 10 PEEP Lee Chest 1990;97 97:425 Surgical ICU, 6 vs. 12 ml/kg 20

RCT Non ALI Small vs. Large V T Significant Difference in Inflammatory Mediator! Michelet Anes 2006;105 105:911 Esophagectomy, 9 ml/kg, zero PEEP vs.

21 RCT Non ALI Small vs. Large V T Significant Difference in Inflammatory Mediator! Michelet Anes 2006; :911 Esophagectomy, 9 ml/kg, zero PEEP vs. 9 ml/kg during 2 lung vent, 5 ml/kg during 1 lung vent with 5 PEEP Choi Anes 2006; :689 Elective Surgery, > 5 hr 12 ml/kg, zero PEEP vs. 6 ml/kg 10 PEEP Zupancich J Thor Cardio Surg 2005; : Cardiac ml/kg, 2 PEEP vs. 8 ml/kg, 10 PEEP Miranda Eur J Cardiothoraic Surg 2005;28 28: Cardiac Surg, CMV vs. OLA in ICU vs. OLA OR Wolthuis Anes 2008; :46 Elective Surgery, 5 hr 12 ml/kg, zero PEEP vs. 6 ml/kg 10 PEEP Main risk factor for ALI large V T (OR 1.3 for ea ml above 6 ml/kg PBW p < Transfusion blood products (OR 3.0, p<0.001) Acidemic ph < 7.35 (OR 2.0 p=0.32) Gajic CCM 2004;32:

22 SCALING OF THE LUNG IN MAMMALS L U N G V O L U M E, liter Whale Dugong 100 SLOPE = 1.02 Manatee Bear Cow Pig Porpoise 10 Goat MAN Rat Mouse Shrew Bat Marmot Racoon Cat Rabbit Guinea Pig Dog Monkey Armadillo Lung Volume = 6.3% BW Tidal Volume = 6.3 ml/kg B O D Y W E I G H T, kg Adapted from SM Tenney & JE Remmers, Nature 1963; 197:54-6; K Schmidt- Nielsen, 1972 Villar, Kacmarek, Hedenstierna. Acta Anaesth Scand 2004; 48: Impact of Ventilator Management on Mortality in ARDS P PLAT < 30 cmh 2 O, mortality reduced Lower the P PLAT,, better the outcome 5-8 ml/kg V T reduces mortality vs. 12 ml/kg P PLAT P PLAT 25 P PLAT < 25 PLAT > 30 cmh 2 O, V T < 6 ml/kg 25 to 30 cmh 2 O, V T 6 to 8 ml/kg 25 cmh 2 O maintain V T <10 ml/kg; 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;

23 Ranieri JAMA 1999;282:54 Impact of a LPVS on pulmonary and systemic inflammatory mediator response in ARDS Cont: V T ml/kg, PEEP cmh 2 0 P flex : V T ml/kg, PEEP cmh 2 0 Outcome: pulmonary and systemic inflammatory mediator response attenuated in the treatment group 28 day Mortality 38% P flex vs. 58% Control, NS flex vs. 23

ALVEOLI - Mortality Before Hospital Discharge Unadjusted p=0.56 Adjusted p= 0.44 25.1 27.2 27.6 24.

T vs. Low PEEP, Moderate V T Control: o V T 9-11 ml/kg PBW, PEEP >5 cmh 2 O Treatment: PEEP P flex + 2 cmh 2 O, V T 5-8 ml/kg PBW

24 ALVEOLI - Mortality Before Hospital Discharge Unadjusted p=0.56 Adjusted p= Low PEEP High PEEP Low PEEP High PEEP Villar, Kacmarek et al CCM 2006;34 34:1311 RCT severe ARDS P/F < 200 mmhg : High PEEP, Low V T vs. Low PEEP, Moderate V T Control: o V T 9-11 ml/kg PBW, PEEP >5 cmh 2 O Treatment: PEEP P flex + 2 cmh 2 O, V T 5-8 ml/kg PBW Targets: PCO mmhg, PO mmhg PCO 2 managed by respiratory rate Treatment: decreased oxygenation - increase PEEP; increased oxygenation - decrease F I O 2 24

25 Villar, Kacmarek et al CCM 2006;34:1311 CONTROL TREATMENT n = 50 n= 53 Mortality 54% Mortality 30% As a result of a randomization problem in one center identified after termination of the study during manuscript revision data from that center had to be eliminated n =45 n = 50 Mortality 53.3% Mortality 32% p = (0.017) EXPRESS Trial Mercat and Brochard RCT High vs. Low PEEP, P/F < 300 mmhg regardless of PEEP or F I O 2 All 6 ml/kg PBW Min Alveolar distension PEEP 5 to 9 cm H 2 O Max PEEP V T set than PEEP to Pplat 28 to 30 Stopped early for futility: 382 vs. 385 pts PEEP 6.9 vs cmh 2 O, Pplat 21 vs. 28 cmh 2 O Mortality 28 days 31.2 vs. 27.8% P = NS Ventilator free days vs , p < Prone or NO and organ failure free days, p <

26 LOVES Trial Meade and Stewart RCT High (n=457) vs. Low PEEP (n=502), P/F < 250 mmhg regardless of PEEP and F I O 2 All 6 ml/kg PBW Control ARDSnet protocol PA/C, RM, PEEP/F I O 2 table PEEP vs cmh 2 O Pplat 28 vs. 25 cmh 2 O Mortality 36.4 vs. 40.4% p =NS Need for rescuer therapy 7.8 vs. 12.0% p < Why the Differences in Outcome in Studies Evaluating PEEP in ARDS? Difference in tidal volume between groups! Method of setting PEEP! Alveoli - use of a PEEP/F I O 2 table LOVES - use of a PEEP/F I O 2 table EXPRESS PEEP to bring Pplat to 28 to 30 CWP Ranieri -P-V curve Amato -P-V curve Villar -P-V curve Patients enrolled into study ALI vs. ARDS 26

27 Villar, Kacmarek AJRCCM 2007;176:795 Impact of Standard ventilator setting on Classification i of level l of lung injury Pt enrolled within 24 hrs of meeting ARDS (P/F < 200 mmhg) criteria Standard ventilator setting evaluated after meeting criteria and 24 hrs later Settings F I O and 1.0 with PEEP 5 and 10 Recommended V T 6-8 ml/kg PBW 170 pts enrolled FIGURE 2. Mortality at T24 Villar, Kacmarek AJRCCM 2007;176:795 50% 45% 40% 35% 30% 25% 20% 15% 10% 5% 0% 50% 45% 40% 35% 30% 25% 20% 15% 10% 5% 0% FiO2=0.5; PEEP= 5 p= % 45% 40% 35% 30% 25% 20% 15% 10% 5% 0% FiO2=0.5; PEEP=10 p=0.001 ARDS ALI ARF ARDS ALI ARF N=140 N=22 N=8 N=99 N=55 N=16 50% FiO2=1; FiO2=1; p= % PEEP=5 PEEP=10 40% 35% 30% 25% 20% 15% 10% 5% 0% ARDS ALI ARF ARDS ALI ARF N=126 N=19 N=25 N=75 N=59 N=36 p=

28 Villar, Kacmarek AJRCCM 2007;176:795 Overall mortality 34.1% (n = 58) 24hrs PEEP > 10 cmh 2 O, F IO 2 > 0.05 ARDS n=99, P/F mmhg ICU mortality 45.5% (45) ALI n=55, P/F mmhg ICU mortality 20% (11) ARF n=16, P/F mmhg ICU mortality 6.3% (1) p= Criteria for Study Entry ALVEOLI and LOVES P/F < 300 mmhg, EXPRESS P/F < 250 mm Hg, no PEEP or F I O 2 criteria Ranieri P/F < 200 mmhg, no PEEP or F I O 2 criteria Amato P/F < 200 mmhg, P/F of enrolled patients , PEEP 9 cmh 2 O, F IO 2 > 0.5 Villar P/F < 200 mmhg, then standard ventilator setting : V T 10 ml/kg, PEEP > 5 cmh 2 O, F I O 2 > 0.5, 24 hr later on standard ventilator settings P/F still < 200 mmhg 28

29 Impact on Mortality in ARDS PEEP > P flex or high PEEP with small V T beneficial ARDS Lb Laboratory Data Amato NEJM 1998;338: Ranieri JAMA 1999;282: Villar, CCM 2006;34: High PEEP with small V T benefit ALI? ALVEOLI NEJM 2004:351: EXPRESS and LOVES? 29

30 Performance of RM - PCV Pressure control ventilation: PEEP cmh 2 O Peak Inspir Press cmh 2 O Inspir Time: 1 to 3 sec Rate: 8 to 20/ min Time 1 to 3 min Set PEEP at 20, ventilate VC, V T 4 to 6 ml/kg PBW, increase rate, avoid auto-peep Measure dynamic compliance Decrease PEEP 2 cm H 2 O Performance of RM -PCV Measure dynamic compliance Repeat until max compliance determined Set PEEP max comp PEEP+2 cm H 2 O Repeat recruitment maneuver and set PEEP at the identified settings, adjust ventilation After PEEP and ventilation set and stabilized, decrease F I O 2 until PO 2 in target range If response is poor, repeat RM, PEEP 25, Peak Pressure 45 If response is poor, repeat RM, PEEP 30, Peak Pressure 50 30

31 Borges, Kacmarek, Amato et al AJRCCM 2006 Borges, Kacmarek, Amato et al AJRCCM

32 Borges, Kacmarek, Amato et al AJRCCM 2006 Borges, Kacmarek, Amato et al AJRCCM

33 Suarez-Sipmann Sipmann CCM 2007;35:214 Tugrul CCM 2003;31 31:738 P/F (mmhg) Baseline 15 min 6 hr ARDS p ARDS exp PEEP (cmh 2 O) Before RM After RM ARDS p ARDS exp F I O 2 Baseline 15 min 6 hr ARDS p ARDS exp

34 *# P/F 150 * * * * BL PRE RM POST RM PEEP 1 HR 4 HR F I O * 0.375* 0.375* PEEP ±3.0 ±3.0 ±4.7 ±4.7 ±4.7 Kamal Respir Care 2006 Relative Contraindications Preexisting pulmonary cysts Preexisting bulbous lung disease Preexisting barotrauma Hemodynamic instability Unilateral/localized lung disease 34

35 Monitoring during RM Set guidelines for aborting the RM, for example: MAP < 60 mmhg or decreases by > 20 mmhg SpO 2 < 88% Heart rate >130 or < 60/ minute New arrhythmias Performance of RM Set F IO 2 at 1.0 Allow time for stabilization Insure appropriate sedation Insure hemodynamic stability 35

36 Improving Oxygenation in the Mechanically Ventilated Patient If F I O 2 can not be decreased below 0.6 by lung recruitment maneuvers and a decremental PEEP trial consider prone positioning! Stoker Chest 1997;111:

37 Gattinoni NEJM 2001; 345: Prone Positioning Cannot be dismissed based on this single study Length of time prone hours/day Ventilatory strategy V T ml/kg PEEP cmh 2O Rate /min Gattinoni NEJM 2001:345;

38 Guerin JAMA 2004;292: Guerin JAMA 2004; : MV days prone vs supine, p=0.93 P/F higher in prone than suprine over the 1 st week of MV p<0.01 Pressure sores, selective intubation, and ETT obstruction all greater in prone, p<0.01 However, Pt only prone for 8 hrs /day! V T 8 to 9 ml/kg actual BW (>10 ml/kg PBW)! No indication of the actual airway pressures! 38

39 Mancebo et al AJRCCM 2006 Prone positioning (76) vs Standard Care (60) Stopped early unable to enroll patients, powered to enroll 200 patients 20 hr/day until PaO 2 > 100 mmhg, F I O 2 0.5, PEEP < 8 cmh 2 O Most patients primary ARDS, 70% pneumonia, 64% sepsis Age years 1 st 24 hours for both groups: PEEP 12 cm H2O, Pplat 32 cmh2o, Vt 8.6 ml/kg, Rate 20/min Mancebo et al AJRCCM 2006 Mortality Prone (33/76) 43% Supine (35/60) 58% p <

40 ACCP-SCCM-AARC Evidenced Based Guidelines For Weaning/Discontinuation of Ventilatory Support Chest 2001 Dec Supplemental Issue ACCP-SCCM-AARC Guidelines Recommendation: Assessment for discontinuation Adequate oxygenation P/F > 150 mmhg PEEP < 8 cmh 2 O F I O 2 < 0.5 ph > Hemodynamic stability; only low dose vasopressors required Spontaneous inspiratory effort 40

41 ACCP-SCCM-AARC Guidelines Recommendation: Discontinuation assessed by spontaneous breathing trial. Tolerance of a spontaneous breathing trial for min sufficient to consider discontinuation! Weaning Trials Brochard et al AJRCCM 1994; 150:896 Esteban et al NEJM 1995; 332: Ely et al NEJM 1996; 335:1864 Kollef et al CCM 1997; 25: Esteban et al AJRCCM 1997; 156:459 Horst et al Arch Surg 1998; 133:483 Esteban AJRCCM 1999;159: Marelich Chest 2000; :459 Kristnan AJRCCM 2004;169:

42 Weaning Time - Days Brochard Esteban SIMV PSV T-piece(S) T-piece(M) Patients Screened Brochard Esteban Screened T-Piece Passed T-Piece Failed % Extubated 76% 77% 42

43 Spontaneous Breathing Trials Both PSV with 7 cm H 2 O and T-piece are acceptable for spontaneous breathing trials Esteban et al AJRCCM 1997;156:459 CPAP of 0 cm H 2 O standard for vast majority, but some may benefit from the use of 5 cm H 2 O CPAP Regardless of level of PSV or CPAP used a SBT is best method to assess for discontinuation! Clinician Driven Protocols Ely NEJM 1996; 335:1864 Kollef CCM 1997; 251: Horst Arch Surg 1998; 133:483 Marelich Chest 2000; :459 Kristnan AJRCCM 2004;169:

44 Control Group Physicians ordered weaning as they believed most appropriate for the patient. Ely Protocol Group Patients evaluated each AM, if: PaO 2 /F I O 2 > 200 PEEP < 5 cmh 2 O Intact airway reflexes RR/V T < 105 No need for continuous infusion of vasopressors or sedation. Patients proceeded to a T-piece/CPAP trial 44

45 CPAP/T-Piece Piece Trial Discontinued if: RR > 35/min SaO 2 < 90% Pulse > 140 min or sustained 20% increase Systolic BP > 180 diastolic > 90 Increased anxiety Increased diaphoresis Ely NEJM 1996 Protocol Control (N=151) (N=149) Weaning Time 1 (0-2) 3 (2-7) < Mech Vent 4.5 (2-9) 6 (3-11) Intern Care 8 ( ) 9 ( ) 0.17 Hosp Care 14 (9-26) 15.5 (6-30) 0.93 All Values Days P 45

46 Ely NEJM 1996 Protocol Control P (N= ) (N=149) Complications 30(20) 62(41) Reintubate < 48 hrs 5(3) 12(8) Any Reintubate 6(4) 15(10) Self Extubate 2(1) 5(3) 0.25 Tracheotomy 13(9) 22(15 15) 0.10 MV > 21 Days 9(6) 20(13) No. of Patients (%) Failure of Weaning Trial (Ely NEJM 1996) RR > 35/min SpO 2 < 90% Pulse > 140/min or 20% increase BP > 20% change, systolic >180, diastolic > 90 Diaphoresis Increased anxiety DO NOT BASE DECISION ON PaCO 2 46

47 Laghi, et al. JAP; 1995 Girard Lancet 2008;371: ABC trial Spontaneous Awaking Trial (SAT) proceeding a SBT vs. Standard of care - SBT 47

48 Girard Lancet 2008;371:126 Patients recruited at 4 different institutions Inclusion Criteria Adult medical ICUs patients MV > 12 hours Exclusion criteria Post CPR CMV > 2 weeks Moribund or withdrawal of life support Profound neurologic deficit Enrollment in another trial SBT Perform Prompt Safety Screen SBT ICU Team Randomization SBT Safety Screen SAT Safety Screen Perform SAT Restart sedation ½ dose 48

49 SAT Safety Screen Patients passed the screen unless: Receiving sedatives for active seizures or alcohol withdrawal Receiving escalating doses for agitation Receiving neuromuscular blockers Evidence of active myocardial ischemia last 24 hours Increased ICP Girard Lancet 2008;371:126 SAT Results Opened eyes 81.6% Tolerated > 4 hours 11. 8% Failed 6.5% SBT Safety Screen Failed 35% (563/1599) Control 34% (336/981) SAT SBT Failed 48% (456/953) Control 47% (284/606) SAT 49

50 Girard Lancet 2008; : Control SAT p VFD Time to discharge ICU 12.6( ) 9.1( ) Hosp 19.2(10.3->28) 14.8( ) Mortality(1yr) yr) 57% 44% Coma 3.0( ) 2.0(0-4.0) Delirium 2.0(0-6.0) 2.0(0-5.0) 0.50 Thank You 50

Invasive Ventilation: State of the Art

ARDSnet NEJM 2000;342:1301 9-30-17 Cox Invasive Ventilation: State of the Art Bob Kacmarek PhD, RRT Harvard Medical School Massachusetts General Hospital Boston, Massachusetts A V T of 6 ml/kg PBW results