Epidemiology of Mechanical Ventilation Antonio Anzueto MD Professor of Medicine University of Texas Health Science Center, San Antonio, Texas

Epidemiology of Mechanical Ventilation

Antonio Anzueto MDProfessor of Medicine

University of Texas Health Science Center, San Antonio, Texas

1952: Copenhagen polio epidemic

First month31 patients with respiratory paralysis

27 patients died (87%)

Bjørn Ibsen• The tank respirator

(negative-pressure) did not provide adequate ventilation

• An elevated CO2-content was indicative of CO2 retention, and not, as the epidemiologists considered, of metabolic alkalosis.

• Early application of positive-pressure ventilation

Hand ventilator used in the Copenhagen polio epidemic of 1952 by hundreds of “ventilators”

0

10

20

30

40

50

60

70

80

90

100

1 2 3 4 5 6 7 8

Mortality July 1952 March 1953

Months

“Anesthesiologic period”

Before 1970

1970 – mid ’90s

•New modes ofVentilation•PEEP

•Respiratory mechanics

late’90s - NowadaysProtectiveventilatory

strategy

How many patients admitted to an ICU receive mechanical ventilation?

What are the characterisitics of these patients?

How is mechanical ventilation applied?

What are the factors associated with outcome ?





USA/CAN SPA ARG BRA CHI POR URUUSA/CAN SPA ARG BRA CHI POR URU

COPDCOPD 16 16 1111 1010 9 9 1010 2323 55

ComaComa 77 2020 3232 2121 1515 1010 4343

Neuromus.Neuromus. 33 44 88 44 1313 1919 22

ARFARF 7474 6464 5050 6666 6262 4747 5050

ARDSARDS 77 99 99 77 2020 33 77

PneumoniaPneumonia 9’69’6 1111 8’58’5 1919 1212 99 1111

TOTALTOTAL

1313

1515

55

6666

88

1010

REASON FOR MV (%)REASON FOR MV (%)

A. Esteban, A. Anzueto, I. Alía et alAm J Respir Crit Care Med 2000;161:1450

LATIN LATIN AMERICAAMERICA

ACACSIMVSIMVSIMV-PSVSIMV-PSVPSVPSVPCVPCV

85 %85 %3 %3 %6 %6 %2 %2 %2 %2 %


74 %74 %5 %5 %9 %9 %2 %2 %7 %7 %

ACAC----------SIMV-PSVSIMV-PSV----------PCVPCV

71 %71 %

14 %14 %

7%7%

DAY 1DAY 1 DAY 4DAY 4 DAY 7DAY 7

USAUSA

CANADACANADA


46 %46 %6 %6 %

15 %15 %2 %2 %

20 %20 %


52%52%4 %4 %

10 %10 %4 %4 %

22 %22 %


39 %39 %3 %3 %

21 %21 %6 %6 %

24 %24 %

EUROPEEUROPE ACACSIMVSIMVSIMV-PSVSIMV-PSVPSVPSVPCVPCV

62 %62 %3 %3 %9 %9 %1 %1 %

15 %15 %


57 %57 %2 %2 %6 %6 %2 %2 %

23 %23 %

ACAC--------SIMV-PSVSIMV-PSVPSVPSVPCVPCV

57 %57 %

5 %5 %4 %4 %

23 %23 %

MODES OF VENTILATIONMODES OF VENTILATION

J.F. Num, et al. BMJ 1972 1 ICU 426 100

23.5%Mech. Vent.

D.L. Gillespie, et al.

Chest 1986

1 ICU --- 327 Resp. failure

A. Esteban, et alChest 1994

42 ICU 630290 46%

Mech. Vent.

A.F. Connors, et al. AJRCCM 1996 5 ICU --- 1.016 COPD

A. Esteban, et al. AJRCCM 2000 412 ICU 4.1531.638

39%Mech. Vent.

M.L. Nevins, et al.Chest 2001

--- --- 166 COPD

A. Esteban, et al. JAMA 2002 361 ICU 15.7575.18333%

Mech. Vent.

S. Karason, et alActa Anaes. Scand. 2002

27 ICU --- 108Mech. Vent.

Place Patients admitted

Patients with MV

Type of patients





Are we changing the way we use mechanical

ventilation ?

1998 vrs 2004

17575 PATIENTS WERE ADMITTED 17575 PATIENTS WERE ADMITTED

FROM 1 TO 31 MARCH 1998FROM 1 TO 31 MARCH 1998

5183 RECEIVED M.V. > 12 h. (33 %)5183 RECEIVED M.V. > 12 h. (33 %)

361 ICUs361 ICUs

20 COUNTRIES20 COUNTRIES

MONITORING WAS PERFORMED MONITORING WAS PERFORMED DAILY DURING THE COURSE DAILY DURING THE COURSE OF MV UNTIL DAY 28OF MV UNTIL DAY 28

FOLLOW-UP WAS PERFORMED FOLLOW-UP WAS PERFORMED UNTIL HOSPITAL DISCHARGEUNTIL HOSPITAL DISCHARGE

A.Esteban, A. Anzueto, F. Frutos, I. Alía et al.JAMA 2002;287:345-355

1998 2004

Age 61 (46, 72) 61 (46, 72)

% Women 37% 40%

SAPS II 44 (34,54) 41 (30, 55)

Demographic Characteristics

A.Esteban, A. Anzueto, et al. JAMA 2002;287:345-355A. Esteban et al AJRCCM 2008; 177:170-177

1

6

21

72

2

10

17

69

Neuro.Msc.Dis

COPD

Coma

ARF

20041998

Reason for Mechanical Ventilation


2.5

4.5

10

8

9

14

21

3

4

7

5

10

11

16

Aspiration

ARDS

CHF

Trauma

Sepsis

Pneumonia

Post-OP

20041998

Etiology of Acute Respiratory Failure






0

10

20

30

40

50

60

70 CMV

SIMV-PSV

PCV

PSVSIMV

1998

1 3 5 7 9 11 13 15 17 19 21 23 25 27

0

10

20

30

40

50

60

70 CMV

SIMV-PSV

PCV

PSVSIMV

1998

1 3 5 7 9 11 13 15 17 19 21 23 25 270

60

10

20

30

40

50

CMVPSV

SIMV-PSVSIMV

PCVCVRP

2004

Ventilator Parameters

1998 2004

Tidal Volume (ml/kg)

9 (8, 10) 7 (6, 8)

RR 16 (14, 19) 17 (14, 20)

PEEP 4 (2,5) 5 (5, 7)

Plateau Pressure

23 (21, 26) 20 (16, 25)

>35 3% 2%


Ventilator Settings Ventilator Settings & &

ARDSARDS

• What are the usual What are the usual ventilator settings?ventilator settings?

• What are the outcomes What are the outcomes associated with small vs. associated with small vs. moderate or large tidal moderate or large tidal volumes?volumes?

MNVTKG1W

20191817161514131211109876543

MNVTKG1W

Freq

uenc

y

60

50

40

30

20

10

0

10 ml/kg Measured Body 10 ml/kg Measured Body Weight (= 12 ml/kg Predicted) is Weight (= 12 ml/kg Predicted) is the 75the 75thth percentile and is within percentile and is within one standard deviation of the one standard deviation of the mean of the average tidal mean of the average tidal volume used in the 1st week of volume used in the 1st week of ARDSARDS

Tidal Volume DistributionTidal Volume Distribution

Mean = 8.81Mean = 8.81

Std Deviation = 2.05Std Deviation = 2.05

Median = 8.66Median = 8.66

PP2525-P-P7575 = 7.50-10.00 = 7.50-10.00

Mean Tidal Volume (ml/kg)Mean Tidal Volume (ml/kg)

(1st week of ARDS)(1st week of ARDS)

PP7575

Fergusson et al CCM 2005; 33:21-30

36

54

82

111

84

64

33 32

0

10

20

30

40

50

60

70

80

90

100

<6 6 7 8 9 10 11 >12

Tidal Volume Category (ml/kg ABW)

% M

orta

lity

0

50

100

150

200

250

Num

ber o

f Pat

ient

s

Number of Patients Observed Mortality Corrected Mortality

Observed and Corrected ICU Mortality by Tidal Volume Category Observed and Corrected ICU Mortality by Tidal Volume Category

496 ARDS Patients496 ARDS Patients


– These data suggest that the using tidal volumes of 6-7 ml/kg may These data suggest that the using tidal volumes of 6-7 ml/kg may be beneficial compared with 8-10 ml/kgbe beneficial compared with 8-10 ml/kg

PLPCORMT

PLP

4239363330272421181512

80

70

60

50

40

Corrected Mortality – PCorrected Mortality – PPLATPLAT

% M

orta

lity

% M

orta

lity

Plateau Pressure Category (cm HPlateau Pressure Category (cm H22O)O)

*

*p=0.37 for slope=0

VTOVCOR6

VTNOTLT6

1312111098765

80

70

60

50

40

Tidal Volume Category (ml/kg ABW)Tidal Volume Category (ml/kg ABW)

Corrected Mortality - VCorrected Mortality - VTT

% M

orta

lity

% M

orta

lity

*p=0.03 for slope=0

*

< 6 ml/kg group excluded


ARDS: Ventilator Parameters

1998 2004

Tidal Volume (ml/kg) 8 (7, 10) 7 (6 , 9)

RR 18 (16, 21) 18 (16, 24)

PEEP 7 (5, 9) 9 (7, 11)

Plateau Pressure 27 (24, 30) 26 (22, 29)

>35 6% 3%

15

8

21

8

45

28

2

11

48

0

10

20

30

40

50

60

PSV SIMV SIMV+PSV MultipleSBT

Daily SBT

1998 2004

Weaning Modes


Outcome: Duration1998 2004

Mechanical Ventilation (days) 3 (2, 7) 4 (2, 9)

Weaning (days) 2 (1, 4) 2 (1,3)


Reintubation/Tracheostomy

1998 2004

Reintubation 14% 14%

Tracheostomy 11% 13%

Time 12 (7, 17) 11 (8, 16)






0

0.2

0.4

0.6

0.8

1

1 6 11 16 21 26 31 36 41 46 51 56

Days after initiation of mechanical ventilation

Su

rviv

al

(%

)COPD ARDS ARF no-ARDS

SURVIVAL CURVES ACCORDING TO REASON FOR M.V.SURVIVAL CURVES ACCORDING TO REASON FOR M.V.

PaOPaO2 2 / FiO/ FiO22

n=77n=7736.8%36.8%DEADDEAD

n=209n=209 50

SAPS IISAPS II

n=449n=449100%100%TOTALTOTAL

n=259n=25957.6%57.6%DEADDEAD

ICU MORTALITYICU MORTALITY

n=135n=13544.7%44.7%DEADDEAD

n=302n=302 NO

ACUTE RENALACUTE RENALFAILUREFAILURE

n=51n=5147.2%47.2%DEADDEAD

n=108n=108 < 100

OR = 2.58OR = 2.58

n=26n=2625.7%25.7%DEADDEAD

n=101n=101100 - 200

OR = 1OR = 1

AGEAGE


n=259n=25957.6%57.6%DEADDEAD


n=135n=13544.7%44.7%DEADDEAD

n=302n=302 NO


n=58n=5862.3%62.3%DEADDEAD

n=93n=93> 50

SAPS IISAPS II

n=11n=1136.6%36.6%DEADDEAD

n=30n=30 48

OR = 1.67OR = 1.67 OR = 8.47OR = 8.47

n=47n=4774.6%74.6%DEADDEAD

n=63n=63> 48


n=259n=25957.6%57.6%DEADDEAD


n=124n=12484.3%84.3%DEADDEAD

n=147n=147YES


PaOPaO2 2 / FiO/ FiO22

n=97n=9790.6%90.6%DEADDEAD

n=107n=107 < 100

OR = 25.98OR = 25.98

n=27n=2767.5%67.5%DEADDEAD

n=40n=40100 - 200

OR = 5.99OR = 5.99

1010No shock, SAPS II between 51 and 35, No shock, SAPS II between 51 and 35, PPaaOO22/F/FiiOO2 2 >150, coma, age 45>150, coma, age 45 103103 16 %16 % 1.73 (1.00 - 3.01)1.73 (1.00 - 3.01)

1111No shock, SAPS II between 51 and 35, No shock, SAPS II between 51 and 35, PPaaOO22/F/FiiOO2 2 >150, no coma, no sepsis>150, no coma, no sepsis 10841084 16 %16 % 1.64 (1.28 - 2.08)1.64 (1.28 - 2.08)

1212 No shock, PNo shock, PaaOO22/F/FiiOO2 2 >150, SAPS II <35>150, SAPS II <35 13321332 10%10% 11

NºNº Failure (%)Failure (%) ODDS RATIO (CI 95%)ODDS RATIO (CI 95%)

11Shock, non acute renal failure, PShock, non acute renal failure, PaaOO22/F/FiiOO2 2

<150<150 104104 81 %81 % 36.93 (21.98 - 62.05)36.93 (21.98 - 62.05)

22 Shock, acute renal failureShock, acute renal failure 533533 77 %77 % 30.26 (23.11 - 39.64)30.26 (23.11 - 39.64)

33Shock, non acute renal failure, Shock, non acute renal failure, PPaaOO22/F/FiiOO2 2 >150, SAPS II >52>150, SAPS II >52 176176 58 %58 % 12.04 (8.76 - 17.5712.04 (8.76 - 17.57

44 No shock, SAPS II >51, comaNo shock, SAPS II >51, coma 247247 52 %52 % 9.61 (7.08 - 13.06)9.61 (7.08 - 13.06)

55 No shock,SAPS II 51, PNo shock,SAPS II 51, PaaOO22/F/FiiOO22 <150 <150 273273 39 %39 % 5.67 (4.19 - 7.66)5.67 (4.19 - 7.66)

66No shock, SAPS II between 51 and 35, No shock, SAPS II between 51 and 35, PPaaOO22/F/FiiOO2 2 >150, coma, age >45>150, coma, age >45 160160 36 %36 % 4.87 (3.36 - 7.04)4.87 (3.36 - 7.04)

77No shock, SAPS II between 51 and 35, No shock, SAPS II between 51 and 35, PPaaOO22/F/FiiOO2 2 >150, no coma, sepsis>150, no coma, sepsis 7676 34 %34 % 4.57 (2.76 - 7.58)4.57 (2.76 - 7.58)

88 No shock, SAPS II >51, no comaNo shock, SAPS II >51, no coma 763763 33 %33 % 4.28 (3.39 - 5.41)4.28 (3.39 - 5.41)

99Shock, non acute renal failure, Shock, non acute renal failure, PPaaOO22/F/FiiOO2 2 >150, SAPS II 52>150, SAPS II 52 332332 29 %29 % 3.68 (2.74 - 4.95)3.68 (2.74 - 4.95)

Outcome: Length of Stay - Mortality1998 2004

ICU – LOS (days) 7 (4, 14) 7 (4, 14)

ICU – Mortality (%) 31% 35%

Hospital – LOS (days) 16 (9, 29) 16 (8, 30)

Hospital – Mortality (%) 40% 40%


Mechanical Ventilation:Conclusions

• Mechanical ventilation is use in a significant number of patients in the ICU.

• Outcome is related to both factors at baseline and complications of critical illness during the course of mechanical ventilation.

• There have being significant changes in the implementation of mechanical ventilation over the last 5 years.

Obrigado

Documents

Epidemiology of Mechanical Ventilation Antonio Anzueto MD Professor of Medicine University of Texas Health Science Center, San Antonio, Texas