Evolución de la VM con presión positivaintensivo.sochipe.cl/subidos/catalogo3/historia VM.pdf · Evolución de la VM con presión positiva Guillermo Bugedo Departamento de Medicina

Evolución de la VM con presión positiva

Guillermo BugedoDepartamento de Medicina Intensiva

Pontificia Universidad Católica de [email protected]

Sunday, April 25, 2010

evolución de la VM con presión positiva

• historia• principios físicos básicos• SDRA y fisiopatología• daño inducido por la VM y ventilación protectora• generaciones de ventiladores


“…you must attempt an opening in the trunk of the trachea and pass into it a tube…, …and you must blow into this so that the lung may expand…, …and the heart take strength afresh and exhibit a great variety of motions”.

From “De humani coporis fabrica”, by Andreas Vesalius (1543).


Robert Hooke(1635-1703)


1667: Keeping a dog alive by blowing through its lungs with bellows



Hooke's law: the stress imposed on a solid is directly proportional to the strain produced, within the elastic limit



(+)


(-) (-)

(+)


“Spirophore”

Eugéne Woillez, 1876


the “iron lung”


1952: la epidemia de poliomielitis y los ventiladores de presión positiva


epidemic of poliomyelitis in Copenhagen

• “It is doubtful indeed if any city of the size of Copenhagen has ever experienced an outbreak of similar magnitude ... for many weeks we received thirty to fifty patients daily, of whom six to twelve were desperately ill ... drowning in their own secretions.

• As we felt that the application of modern principles of anaesthesia to the problem of obstructed airways and respiratory insufficiency in poliomyelitis might improve our results anaesthetists were invited to join our staff, the first being Dr. Bjørn Ibsen.”

Lassen HCA (1954) The Epidemic of Poliomyelitis in Copenhagen, 1952. Proc Roy. Soc. Med 47:67





• Dr Bjørn Ibsen was called into consultation on August 25th.

• In the preceding three weeks there had been 31 patients with life threatening poliomyelitis; 28 of these had died.

Bjørn Ibsen




• On August 27th the first patient was treated with the method that was to become the treatment of choice:– tracheotomy just below the

larynx– inflatable rubber cuff tube in

trachea– frequent suction– repeated bronchoscopy– postural drainage– manual positive pressure

ventilation using oxygen and nitrogen.



manual positive pressure ventilation



• At times there were as many as 70 patients requiring artificial respiration.

• Students from the University provided the manpower (handpower!). Overall 1400 students were involved during the course of the epidemic. None of them contracted the disease.

• By the end of the year the mortality in these severe cases had fallen from 87% to 26%.

Lassen HC. A preliminary report on the 1952 epidemic of poliomyelitis in Copenhagen with special reference to the treatment of acute respiratory insufficiency. Lancet. 1953 Jan 3;1(6749):37-41.


los ventiladores de presión


first use of the Clevedon ventilator

Macrae et al, September 1953


P

t

t

V

gentileza Dr J. Urzúa

P límite


P

t

t

V


P límite


ventilador de presión


IN: t LIM: P CIC: P

Presión(cmH2O)

Flujo(lpm)




IN: t LIM: P CIC: P

Presión(cmH2O)

Flujo(lpm)




IN: t LIM: P CIC: P

Presión(cmH2O)

Flujo(lpm)




IN: t LIM: P CIC: P

Presión(cmH2O)

Flujo(lpm)

riesgo de hipoventilación-pat restrictiva-pat obstructiva-tos-desadaptación


Bird Mark 7

circa 1955


Puritan-Bennett PR-2

circa 1963


la medicina intensiva había nacido…


Ashbaugh DG, Bigelow DB, Petty TL, Levine BEAcute respiratory distress in adults

Lancet, 1967 Aug 12


• The article outlined clinical, radiological, biochemical and pathological features of a pattern of acute respiratory distress in 12 patients:

• “The clinical pattern... includes severe dyspnoea, tachypnoea, cyanosis that is refractory to oxygen therapy, loss of lung compliance, and a diffuse alveolar infiltrate seen on chest X-ray”.

• It was noted that none of the patients had chronic lung disease and the precipitant of the disorder was varied with severe trauma preceding onset in seven patients, viral infection in four patients and pancreatitis in one patient.


Lancet, 1967 Aug 12


• Chest X-ray appearances consisted of “patchy, bilateral alveolar infiltrates”, the severity of which paralleled the clinical condition.

• “At necropsy in seven patients, gross inspection showed heavy and deep reddish-purple lungs... the appearance resembled liver tissue”.

• Microscopic appearances were consistent with current descriptions, including the hyaline membrane which prompted comparison with neonatal respiratory distress syndrome.


Lancet, 1967 Aug 12


discussion (1967…)

• “In view of the similar response of the lung to a variety of stimuli, a common mechanism of injury is postulated. The loss of lung compliance, refractory cyanosis, and microscopic atelectasis point to alveolar instability as a likely source of trouble”.

• They postulated that surfactant dysfunction was a significant contributor to alveolar collapse and acknowledged that PEEP may be beneficial in preventing atelectasis.

• but, “The use of PEEP merely buys time: unless the underlying process can be successfully treated or reversed the prognosis is grave”.


Lancet, 1967 Aug 12


y aquí empezó a usarse el PEEP…


válvulas de umbral (threshold resistor)

presión

flujo

presión = F / s


válvulas de umbral (threshold resistor)

presión

flujo

presión = F / s


presión

flujo

válvulas de flujo

presión = R x flujo


presión

flujo

válvulas de flujo

presión = R x flujo


Falke KJ, et al.J Clin Invest. 1972 Sep;51(9):2315-23.


Falke KJ, et al.J Clin Invest. 1972 Sep;51(9):2315-23.

• 10 patients• Pa:FiO2<300 on ZEEP• Vt 8.9 to 24.1 ml/kg• ZEEP and PEEP 5, 10, and

15 cmH20


estudio internacional VM...

• 15.757 pac’s admitidos a 361 UCI’s en marzo 1998…• 5.183 (33%) →VM x 6 días ( 31%)• 231 (4,5%) pac’s SDRA ( 52%)

día 1 día 2 día 3• pac’s 231 174 82• PEEP, media±DS 8±4 9±3 9±3

mediana (rango) 8 (5-10) 10 (6-12) 9 (5-12)• pac’s sin PEEP 34 (16%) 14 (8%) 8 (10%)

Esteban A, et al. JAMA 2002; 287: 345-355.


estudio internacional VM...

• 15.757 pac’s admitidos a 361 UCI’s en marzo 1998…• 5.183 (33%) →VM x 6 días ( 31%)• 522 (10,1%) pac’s COPD ( 22%)

día 1 día 2 día 3• pac’s 522 283 85• PEEP, media±DS 5±2 5±2 6±3

mediana (rango) 5 (4-5) 5 (5-6) 5 (4-7)• pac’s sin PEEP 218 (47%) 128 (45%) 33 (39%)

Esteban A, et al. JAMA 2002; 287: 345-355.


los ventiladores de volumen


ventilador de presión vs volumen


IN: t LIM: P CIC: P

ventilador devolumen

Presión(cmH2O)

Flujo(lpm)




IN: t LIM: P CIC: P


IN: t LIM: V CIC: t

Presión(cmH2O)

Flujo(lpm)




IN: t LIM: P CIC: P


IN: t LIM: V CIC: t

Presión(cmH2O)

Flujo(lpm)


Diseño mecánico (Harvard pump)

La duración del ciclo depende de la velocidad del motor. La inspiración y la espiración duran lo mismo. El límite inspiratorio es el volumen de desplazamiento del pistón. Se puede agregar válvula de escape para evitar sobrepresión. La espiración es activa (aspiración a presión negativa).



Puritan Bennett MA-1

circa 1967


Bear-1 (“flipper”)

circa 1975



ventilación convencional hacia 1980…

• 1960: VM en pacientes quirúrgicos sometidos a anestesia y relajación muscular– Vt 10-15 ml/Kg para prevención de atelectasias

• 1970: principios de manejo en SDRA– Vt 10-15 ml/Kg– PEEP 5-10-15... cmH2O– PVA ↑↑↑ (controladas, pero no restringidas)– atención en efectos HMD, FiO2 y barotrauma...

• incidencia barotrauma (macro)– PVA 50 cmH2O → 50%– PVA70 cmH2O → 80%

Haake R, et al. Chest 1987; 91: 608.


15/01 30/01

barotrauma


14/0 45/0

Webb and Tierney. Am Rev Respir Dis 1974; 110:556-565.

edema pulmonar producido por la ventilación con presión (+) con altas presiones de inflación


ventiladores de 3ª generación


asistencia por presión


ventiladormicroprocesado

Presión(cmH2O)

Flujo(lpm)





Presión(cmH2O)

Flujo(lpm)





Presión(cmH2O)

Flujo(lpm)





Presión(cmH2O)

Flujo(lpm)

IN: t LIM: P CIC: P IN: t-P LIM: P CIC: t-F


Siemens 900

circa 1982


Puritan-Bennett 7200

circa 1984


tiempos modernos


Wilhelm Conrad Röntgen (1845-1923)premio Nobel Física 1901

Allan M. Cormack (1924-1998)Godfrey N. Hounsfield (1919-2004)

premio Nobel Medicina 1979


mid 80’s: baby lung


baby lung: lung surface in ARDS is small→ main pathophysiologic principle for protective ventilation

Gattinoni L et al. Intensive Care Med 1986; 12: 137-142.Gattinoni L & Pesenti A. Intensive Care Med 2005; 31: 776–784.

mid 80’s: baby lung


0

1000

2000

3000

4000

normal ARDS

weightgas vol

baby lung

• CT-scan study in ARDS:– densities 70-80% at ZEEP– total volume N– gas volume ↓↓↓

• small lung: less surface available for gas exchange…

Gattinoni L et al, Anesthesiology 1987.Gattinoni L et al. Intensive Care Med 1986; 12: 137-142.

Gattinoni L & Pesenti A. Intensive Care Med 2005; 31: 776–784.


0

1000

2000

3000

4000

normal ARDS

weightgas vol

baby lung

• CT-scan study in ARDS:– densities 70-80% at ZEEP– total volume N– gas volume ↓↓↓

• small lung: less surface available for gas exchange…

Gattinoni L et al, Anesthesiology 1987.

→ main pathophysiologic principle for protective ventilation

Gattinoni L et al. Intensive Care Med 1986; 12: 137-142.Gattinoni L & Pesenti A. Intensive Care Med 2005; 31: 776–784.


• retrospective case series• 50 patients with severe ARDS (PaO2/FiO2 94)

– limited PIP by reducing Vt, allowing spontaneous breathing with SIMV and disregarding hypercapnia.

– mean maximum PaCO2 was 62 mmHg (highest 129 mmHg– hospital mortality was lower than that predicted by Apache II

(16% vs. 39.6%, chi 2 = 11.64, p<0.001).

Hickling KG, et al. Intensive Care Med. 1990;16(6):372-7.


el gran salto

• normalizar gases arteriales• VT elevados para prevenir atelectasias…

ventilación convencional


el gran salto



• mecanoprotección• limitar Vt y presiones• CO2 secundario

ventilación protectora


el gran salto



• mecanoprotección• limitar Vt y presiones• CO2 secundario

ventilación protectora

la hipercapnia permisiva no es una modalidad ventilatoria per se, sino una consecuencia de la ventilación con bajo Vt en un pulmón con poca superficie de intercambio (baby lung)


the fact…!!!

Psycho (1960)


mechanicalventilation

ALI/ARDS

the fact…!!!

Psycho (1960)


opening-closing

• 44 pat‘s ARDS:– Pa/fiO2 ~150– LIS (Murray) 2.5

• control group (n=19)– TV 11.1 ml/Kg ®Ppl 31

cmH2O– PEEP 6.5 cmH2O– PaCO2 37.4 mmHg

• protective strategy (n=18)– TV 7.6 ml/Kg → Ppl 25

cmH2O– PEEP 14.8 cmH2O– PaCO2 46.9 mmHg

LBA

Ranieri VM et al. JAMA 1999; 282: 54-61.

control protective

TNF-α

IL-8

IL-6



• Brochard L, et al. AJRCCM 1998; 158: 1831-8.– 108 pac, 25 centros, SDRA<72 horas, OSF=1– low Vt: Pplat ≤25 cmH2O 48%– control: Vt ≥10 ml/Kg, Ppeak <60, PaCO2 38-42 41%



• Stewart TE, et al. N Engl J Med. 1998;338: 355-61.– 120 pac SDRA<24 horas.– low Vt: Vt ≤8 ml/Kg, Ppeak ≤30 cmH2O 48%– control: Vt 10-15, Ppeak <50 cmH2O 46%




• Brower R, et al. Crit Care Med. 1999; 27: 1492-8.– 52 pac SDRA, algoritmo similar FiO2-PEEP.– low Vt: Vt ≤8 ml/Kg, Pplat ≤30 cmH2O 50%– control: Vt 10-12, Pplat ≤50 cmH2O 46%




• Brower R, et al. Crit Care Med. 1999; 27: 1492-8.– 52 pac SDRA, algoritmo similar FiO2-PEEP.– low Vt: Vt ≤8 ml/Kg, Pplat ≤30 cmH2O 50%– control: Vt 10-12, Pplat ≤50 cmH2O 46%

• Amato M, et al. NEJM 1998; 338: 347-354.– 53 pac SDRA, algoritmo similar FiO2-PEEP.– low Vt: curva P-V, Vt ≤4-6, PEEP 16, hipercapnia 38%– control: Vt 11-12, least PEEP (8-9), normocarbia 71%




Vt 6 ml/kg: mort 31%Vt 12 ml/kg: mort 39%


Tobin MJ. Culmination of an era in research on the ARDS.N Engl J Med 2000; 342: 1360–1361.

ARDS network: ¿fin de la historia?


Tobin MJ. Culmination of an era in research on the ARDS.N Engl J Med 2000; 342: 1360–1361.

→Vt 6 ml / kg… estándar en SDRA...

ARDS network: ¿fin de la historia?


clinical trials

Protective ControlAuthor n Ppl PEEP Mort Ppl PEEP Mort p

Brochard'98 108 25.7 10.7 48.0% 31.7 10.7 41.0% ns Stewart'98 120 22.3 8.6 48.0% 26.8 7.2 46.0% ns Ranieri'99 44 24.6 14.8 38.0% 31.0 6.5 58.0% 0.19Brower'99 52 27.0 9.3 50.0% 30.0 8.2 46.0% nsAmato’98 53 31.8 16.3 38.0% 34.4 6.9 71.0% <0.001ARDSnet'00 861 25.0 9.4 31.0% 33.0 8.6 39.8% 0.007Kallet'05 292 27.5 10.0 32.0% 33.8 7.4 51.0% 0.004Villar’06 95 30.6 14.1 34.0% 32.6 9.0 55.5% 0.041 low PEEP high PEEPARDSnet'04 549 24.0 9.1 24.9% 27.0 14.7 27.5% nsMercat’08 767 21.1 8.4 39.0% 27.5 15.8 35.4% nsMeade’08 983 24.9 10.1 40.4% 30.2 15.6 36.4% ns


clinical trials

Protective ControlAuthor n Ppl PEEP Mort Ppl PEEP Mort p

Brochard'98 108 25.7 10.7 48.0% 31.7 10.7 41.0% ns Stewart'98 120 22.3 8.6 48.0% 26.8 7.2 46.0% ns Ranieri'99 44 24.6 14.8 38.0% 31.0 6.5 58.0% 0.19Brower'99 52 27.0 9.3 50.0% 30.0 8.2 46.0% nsAmato’98 53 31.8 16.3 38.0% 34.4 6.9 71.0% <0.001ARDSnet'00 861 25.0 9.4 31.0% 33.0 8.6 39.8% 0.007Kallet'05 292 27.5 10.0 32.0% 33.8 7.4 51.0% 0.004Villar’06 95 30.6 14.1 34.0% 32.6 9.0 55.5% 0.041 low PEEP high PEEPARDSnet'04 549 24.0 9.1 24.9% 27.0 14.7 27.5% nsMercat’08 767 21.1 8.4 39.0% 27.5 15.8 35.4% nsMeade’08 983 24.9 10.1 40.4% 30.2 15.6 36.4% ns

P distensión = P meseta - PEEP


driving pressure (Pplateau - PEEP)














at risk…safe zone



clinical data: low vs high PEEP

low PEEP high PEEP ( max recruitment)

Author n Ppl PEEP Mort Ppl PEEP Mort p

ARDSnet'04 549 24.0 9.1 25% 27.0 14.7 27% ns

Mercat’08 767 21.1 8.4 31% 27.4 15.8 27% ns

Meade’08 983 24.0 9.4 40% 27.0 13.5 36% ns


at risk…safe zone



Meade MO, et al. JAMA 2008

Mercat A, et al. JAMA 2008

Express study

LOV study

high (15-16) vs low (9-10) PEEP (1750 patients)


Meade and Mercat study: 1750 patientslow PEEP

890high PEEP

860

severehypoxemia

184706

severehypoxemia

94 766

Gattinoni L, Caironi P. JAMA 2008; 299: 691-3.

20.7% 10.9%



890high PEEP

860

severehypoxemia

184706

severehypoxemia

94 766


20.7% 10.9%

S: 77NS: 107

S: 459NS: 247

S: 37NS: 57

S: 514NS: 252

58.2% 60.6%35.0% 32.9%



890high PEEP

860

severehypoxemia

184706

severehypoxemia

94 766


20.7% 10.9%

pulmonarydeath12.0%

non-pulmdeath27.8%

globalmortality39.8%

pulmonarydeath6.6%

non-pulmdeath29.3%

globalmortality35.9%

S: 77NS: 107

S: 459NS: 247

S: 37NS: 57

S: 514NS: 252

58.2% 60.6%35.0% 32.9%


concept: VILI is at first mechanical

overdistentionopening-closing

release of mediators

↑ ventilatory requirements

increase in permeability

Pinhu L, et al. LANCET • Vol 361 • January 25, 2003Fan E, Needham DM, Stewart TE. JAMA 2005; 294: 2889-96.

• fem, 44 yo, pancreatitis• 6 days on MV before transferred• died









biotrauma

barotrauma / volutrauma

atelectrauma









biotrauma

barotrauma / volutrauma

atelectrauma

strain ⇒ Vt / EELV



Hooke's law: the stress imposed on a solid is directly proportional to the strain produced, within the elastic limit


qué tienen en común?


su volumen corriente es 6 ml/kg…!!!

qué tienen en común?


Tenney SM and Remmers JE. Nature 1963; 197: 54-56,


falla respiratoria severa

en cualquiera estrategia, el punto más importante es limitar el volumen corriente a no

más de 6 ml/kg (peso ideal)

• frecuencias respiratorias rápidas 30-35 /min• modalidad ventilatoria no afecta• protocolos sedación y analgesia• protocolos reanimación y depleción• control infecciones


ventiladores de 4ª generación


classic modes of ventilation

output inputpatient physicianpatient

assistanceVt - RR - I:EFiO2 - PEEP


classic modes of ventilation

output inputpatient physician

patient adapts to ventilator

patientassistance

Vt - RR - I:EFiO2 - PEEP


close loop technology

output input

patientdemand

patientassistance

patient physicianinspiratory

supportFiO2 - PEEP


hipoxemia permisiva

Grocott MP, et al. N Engl J Med 2009; 360: 140-9.



21% mortality rate!!!


historia VM

SDRA

iron lung

ventpresión

ventvolumen

ventiladoresmicroprocesados

VPP

PEEP IMV PS

1950 1960 1970 1980 1990 2000 2010

ustedestá aquí

ventiladores4a generación


historia VM

SDRA

iron lung

ventpresión

ventvolumen


VPP

PEEP IMV PS

CT-scan

1950 1960 1970 1980 1990 2000 2010

ustedestá aquí



historia VM

SDRA

iron lung

ventpresión

ventvolumen


VPP

pulmón rígido

PEEP IMV PS

CT-scan

1950 1960 1970 1980 1990 2000 2010

ustedestá aquí



historia VM

SDRA

iron lung

ventpresión

ventvolumen


VPP

pulmón rígido

babylung

PEEP IMV PS

CT-scan

1950 1960 1970 1980 1990 2000 2010

ustedestá aquí



historia VM

SDRA

iron lung

ventpresión

ventvolumen


VPP

pulmón rígido

babylung

PEEP IMV PS

CT-scan

daño inducido por la VM

1950 1960 1970 1980 1990 2000 2010

ustedestá aquí



historia VM

SDRA

iron lung

ventpresión

ventvolumen


VPP

pulmón rígido

babylung

PEEP IMV PS

CT-scan ARDSnetstudy


1950 1960 1970 1980 1990 2000 2010

ustedestá aquí



historia VM

SDRA

iron lung

ventpresión

ventvolumen


VPP

pulmón rígido

babylung

PEEP IMV PS

CT-scan ARDSnetstudy


1950 1960 1970 1980 1990 2000 2010

ustedestá aquí


estrategia protectora


objetivos de la VM... siglo XXI

• sostener la ventilación• reclutar alvéolos colapsados

– mejorar intercambio– ↓ trabajo ventilatorio

• evitar el daño inducido por la ventilación mecánica– limitar presión transpulmonar


principles of protective ventilation



• limit Vt– ↓ transpulmonary pressure– no magic number…




• optimize PEEP– optimize recruitment → mecánica, ↓Vd/Vt– no magic number…





• analgesia based sedation– ↓ ventilatory drive





• analgesia based sedation– ↓ ventilatory drive

try the lung gently


Bundles: prevención NAV

• No realizar cambios en circuito ventilatorio a menos que esté específicamente indicado

• Higiene de manos estricto usando alcohol• Staff apropiadamente educado y entrenado• Incorporación de vacaciones de sedación y

protocolos de destete• Aseo oral con clorhexidina

A European care bundle for prevention of ventilator-associated pneumonia.Rello J. et al. Intensive Care Med 2009.




Documents

Evolución de la VM con presión positivaintensivo.sochipe.cl/subidos/catalogo3/historia VM.pdf · Evolución de la VM con presión positiva Guillermo Bugedo Departamento de Medicina