PAPER DE LA VNI EN LA RETIRADA DE LA VENTILACIÓ INVASIVA I FRACÀS D EXTUBACIÓ Dr. Miquel Ferrer UVIIR, Servei de Pneumologia, Hospital Clínic, IDIBAPS, CibeRes, Barcelona. E- mail: miferrer@clinic.ub.es Barcelona, 3 de novembre de 21 www.idibapsrespiratoryresearch.org
Withdrawal of mechanical ventilation
Weaning period 4-5% of total duration of ventilation Longer ventilation related to higher mortality Survival and prolonged mechanical ventilation 5,2 ventilated patients 361 ICUs Europe, North and South America Esteban A. JAMA 22; 287:345
Non-invasive ventilation 11.1% Patients ventilated >12 h (n=4,968) Planned extubation (n=1,649) Prior MV: 4 days Weaning: 4% of total MV Spontaneous breathing trial 62% T-piece: 71% Low levels PSV: 14% Extubated after 1 st weaning attempt 77% Needed >1 weaning attempt 23% Re-intubation rate: 12% Tracheostomy: 12.5% Median timing: 11 days Mode of ventilation: PSV: 55% ACV: 28% SIMV-PSV: 15% SIMV <2%
New classification of weaning Estimated 69% Estimated 31%
Comportamiento de la función cardio-pulmonar en el éxito de la retirada de la VM Ventilación mecánica (con presión positiva) Respiración espontánea (con presión negativa) actividad de músculos respiratorios retorno venoso Patrón respiratorio rápido y superficial demandas metabólicas (consumo O 2, producción CO 2 ) Respuesta cardiovascular adecuada ( Aporte periférico de O 2 ) Remodelado de factores intra y extrapulmonares determinantes de los gases arteriales
35 Respiratory rate 8 Tidal volume (ml) 3 7 25 2 15 * 6 5 4 * 1 3 ACV PSV SB ACV PSV SB Rapid and shallow breathing pattern during spontaneous breathing No changes in minute ventilation
23 PaO 2 /FiO 2 6 PaCO 2 22 21 55 5 * 2 ACV PSV SB 45 ACV PSV SB 8 Q P T (L/min) V O 2 (mmhg) 7 6 5 4 ACV PSV SB 42 4 38 * p<.1 * p<.5 36 34 ACV PSV SB Q T and P V O 2 increased during spontaneous breathing, preventing a fall in PaO 2
.8.7.6.5.4.3 Mean Q * 1.7 1.6 1.5 1.4 1.3 1.2 Dispersion of blood flow 6 55 5 45 4 Dead space (% V A ) * ACV PSV SB ACV PSV SB ACV PSV SB Increase of dead space and overall lung perfusion during spontaneous breathing without changes in V A /Q mismatching
Retirada de la ventilación mecánica con éxito Patrón ventilatorio rápido y superficial Mínimos cambios en los factores intrapulmonares del intercambio de gases Respuesta cardiovascular adecuada: Aumento Q T, DO 2 y P V O 2 No cambios en oxigenación arterial
Pathophysiologic bases of weaning failure Load Capacity Increased: Breathing drive Workload Ventilatory demands Left ventricular afterload Inappropriate cardiovascular response Hyperinflation Reduced inspiratory muscle strength Rapid and shallow breathing Respiratory distress Hypercapnia-acidosis
Unsuccessful weaning in COPD patients Rapid and shallow breathing pattern Increased workload of respiratory muscles R INSP E DYN PEEP I Tobin MJ. Am Rev Respir Dis 1986;134:1111-8 Jubran A. Am J Respir Crit Care Med 1997;155:96-15
Inappropriate cardiovascular response in unsuccessful weaning Increased venous return to right ventricle Large negative deflections in intrathoracic pressure Increased left ventricular afterload Fall of P V O 2 and S V O 2 Jubran A. AJRCCM 1998;158:1763 Lemaire F. Anesthesiology 1988;69:171
Approaches proposed to optimize weaning Protocol-driven weaning: Daily screening of respiratory function Respiratory therapists vs physicians Pressure-support vs assist-control ventilation Daily spontaneous breathing trials Automated systems 2-3% patients can not be extubated after the first weaning attempt
NIV as part of a protocol-driven weaning Improvement of underlying indication for MV DAILY SCREENING of respiratory function NO Mechanical ventilation and daily screening Acceptable parameters No signs of poor tolerance EXTUBATION YES SPONTANEOUS BREATHING TRIAL Contraindications for NPPV GRADUAL WITHDRAWAL OF VENTILATORY SUPPORT Signs of poor tolerance Prolonged ventilation Consider Tracheotomy No contraindications for NPPV Chronic respiratory disease? Hypercapnia? EXTUBATION + NPPV Adapted from Esteban A. Intensive Care Med 1998;24:999
Difficult weaning and non-invasive ventilation
The addition of PEEP to non-invasive PSV resulted in additional decrease of the work of breathing
The improvement of respiratory blood gases is due to higher alveolar ventilation NIV attained a more efficient breathing pattern V A /Q relationships did not change
Non-invasive PSV in ventilator-dependent chronic respiratory patients T-piece trial Invasive-PSV Extubation Spontaneous breathing Noninvasive-PSV cmh 2 O x s/l 6 4 2 Vitacca M. Am J Respir Crit Care Med 21;164:638 PTPdi/V TE * ** i-psv n-psv T-piece S.B. mmhg 9 8 7 6 5 4 PaCO 2 i-psv n-psv T-piece
Prolonged weaning associated with worse outcome: No different outcomes between simple and difficult weaning Factors implicated in prolonged weaning no assessed Patients ventilated >48 h undergoing planned extubation (n=181) Simple weaning (n=81) Difficult weaning (n=67) Prolonged weaning (n=33) Characteristics and outcomes from the 3 groups Predictive factors for prolonged weaning and survival Sellares J, Ferrer M et al. Submitted
4 35 3 25 2 5 4 3 2 1 Is prolonged weaning clinically relevant? Hospital stay ICU mortality n=1 p=.18 p<.1 n=8 n=14 Simple weaning Difficult weaning Prolonged weaning 5 4 % 3 2 1 5 4 % 3 2 1 Ventilator-associated pneumonia n=12 Hospital mortality n=15 p=.5 n=13 p=.4 n=16 n=14 n=16 1 9 8 % 7 6 5 p=.19 9-day survival 1 2 3 4 5 6 7 8 9 Days Simple Difficult Prolonged Sellares J, Ferrer M et al. Intensive Care Med (1 st revision)
mmhg The problem of hypercapnia during weaning 6 Simple weaning PaCO Difficult weaning 2 Prolonged weaning 55 5 45 4 Simple p=.1 Difficult Prolonged % 1 9 8 7 6 5 p=.1 9-day survival Normocapnia Hypercapnia 1 2 3 4 5 6 7 8 9 Days Independent predictors of prolonged weaning and survival Prolonged weaning Cutoff Adj. OR 95%-CI p value Heart rate SBT 15 min -1 1.6 1.29-1.91 <.1 PaCO 2 SBT 54 mmhg 1.71 1.27-1.118.1 Decreased 9-d survival Adj. OR 95%-CI p value Re-intubation criteria 5.33 3.14-9.9 <.1 PaCO 2 during SBT 1.33 1.11-1.55.3 Sellares J, Ferrer M et al. Intensive Care Med (1 st revision)
CO 2 retention and outcome of weaning Increased CO 2 retention during spontaneous breathing strongly predicts prolonged weaning and mortality Higher PaCO 2 also related with respiratory failure after extubation (OR: 1.46, p=.4) Increased PaCO 2 is amenable of medical intervention Detection of high levels of PaCO 2 implement measures to shorten weaning and avoid re-intubation (NIV!!!)
Clinical advantages of the early removal of the ETT Communication Patient comfort Effective cough Mucociliary clearance Sinus drainage Sedation Nosocomial infection/vap Work of breathing Adapted from Noninvasive Positive Pressure Ventilation, NS Hill ed., Futura Pub 21
When to use NIV during withdrawal of mechanical ventilation? Weaning failure (difficult and prolonged) Early extubation Respiratory failure after extubation: Management Prevention
NPPV in COPD and early extubation One failed weaning attempt (within 48 h of MV) Mean PaCO 2 : 62-64 mmhg, mean pha: 7.3-7.31 Patients who could not be weaned from MV Days 2 15 1 5 % 6-d weaning success p<.1 1 n=22 8 n=17 6 4 2 NIV Standard MV duration 3 ICU stay p<.5 p<.1 2 1 NIV Standard NIV Standard % 2 1 n= NIV Pneumonia ICU survival n=7 1 p<.1 p<.1 8 n=18 3 n=23 Standard % Standard weaning NIV 6 4 2 NIV Standard Nava S. Ann Intern Med 1998;128:721
NPPV in ACRF and single weaning failure Single failed weaning attempt Mean PaCO 2 : 6-64 mmhg, mean pha: 7.33-7.35 Duration of endotracheal mechanical ventilation 3-day reduction of ETMV No changes in major clinical outcomes Small sample size Girault C. Am J Respir Crit Care Med 1999;16:86
NIV during persistent weaning failure Failed weaning attempts for 3 consecutive days 77% chronic respiratory (6% COPD) Mean PaCO 2 : 52-54 mmhg 25 Mean pha: 7.37-7.38 % 8 6 4 2 Nosocomial pneumonia p=.42 n=5 NIV n=13 Control 8 6 4 2 Ferrer M et al. Am J Respir Crit Care Med 23;168:7 Tracheostomy p<.1 n=13 n=1 NIV Control 2 15 1 5 Duration of intubation 1 p=.3 8 6 4 2 NIV Standard ICU Survival n=19 NIV p=.45 n=13 Control 1 Successfully weaned patients 8 6 4 2 % p=.2 NIV Control 1 2 3 4 5 Duration of ventilation (days) 1 8 6 4 9-day survival NIV Control p=.44 1 2 3 4 5 6 7 8 9
BMJ. 29 May 21;338:b1574. doi: 1.1136/bmj.b1574 Meta-analysis of 12 RCTs Extubation with immediate NPPV vs weaning using IPPV
NIV during difficult weaning Primary end-point: Shortening weaning Secondary end-points: Decreasing complications associated to prolonged MV and mortality Currently available RCTs: Nearly all with chronic respiratory disorders and hypercapnia Frequent cardiac co-morbidity Limited number of patients: Overall 53 in 12 trials, but Only 3 trials in high quartile peer-review journals (126 patients) Future multicentre RCTs? France, 2 inclusions
Clinical relevance of extubation failure
Incidence and outcome of re-intubation Incidence: 6-23% planned extubations Crude mortality rate: 12-68% Independent risk factor for: Nosocomial pneumonia Increased mortality Increased length of stay Torres A. Am J Respir Crit Care Med 1995;152:137 Epstein SK. Chest 1997;112:186
Patients ventilated >12 h (n=4,968) Non-invasive ventilation 11.1% Planned extubation (n=1,649) Prior MV: 4 days Weaning: 4% of total MV Spontaneous breathing trial 62% Extubated after 1 st weaning attempt 77% Needed >1 weaning attempt 23% Re-intubation rate: 12%
Effect of failed extubation on the outcome of mechanical ventilation Hospital mortality 5 p<.1 25 ICU stay p<.1 4 Hospital stay p<.1 4 2 3 % 3 2 Days 15 1 2 Extubation success Extubation failure 1 5 1 Independent predictors of death Epstein SK. Chest 1997;112:186
Time from extubation to re-eti -12 h Incidence Mortality 13-24 h 25-48 h 49-72 h 2 4 6 8 % Time to re-eti was an independent predictor of mortality
Predicting extubation outcome Better prediction Shorter duration of MV Delay of extubation Advance of extubation Risks derived from prolonged ventilation Risks derived from reintubation Is there an optimal rate of post-extubation failure? Test accuracy may be less important if NIV is effective for extubation failure
Respiratory failure Heart failure Aspiration-excess secretions Upper airway obstruction Encephalopathy Causes potentially responding to NIV accounted for half of reintubations and had high mortality Mortality Incidence Other 2 4 6 %
When can NIV be used after extubation? Respiratory failure after extubation: Management (late use) Prevention (early use
NPPV for post-extubation respiratory distress 81 patients Mixed population: Cardiac: 35% Respiratory: 32% (COPD 11%!!!!) % Methods.... After the first year, patients with an acute exacerbation of COPD were excluded because the randomized trial evidence strongly supported the use of NPPV for these patients and because NPPV was therefore applied when these patients developed respiratory distress. 8 6 4 2 n=28 NPPV Re-IT n=29 Standard 8 6 4 2 Hospital survival n=27 n=29 NPPV Standard Keenan SP. JAMA 22;287:3238
NPPV in the management of post-extubation failure 221 patients Mixed population: COPD 1%!!!! % 6 4 2 Re-ETI n=55 n=51 3 2 1 Time to re-eti (hours, median) p=.41 6 4 % 2 ICU mortality p=.38 n=3 n=15 NIV Control NIV Control NIV Control Esteban A. N Engl J Med 24;35:2452
NPPV in the management of post-extubation failure Standard medical therapy These patients could be reintubated or crossed over to NIV if they met the predefined criteria for reintubation.. % 6 4 Re-IT ICU mortality p=.12 n=44 3 n=62 n=31 p=.31 2 n=12 2 NPPV Standard 1 NPPV Standard Esteban A. N Engl J Med 24;35:2452
When can NIV be used after extubation? Respiratory failure after extubation: Management (late use) Prevention (early use
(Crit Care Med 25; 33:2465 247) Randomised clinical trial Successful weaning trial (33% COPD) At high-risk for RF after extubation % 3 2 1 p=.27 n=4 Re-IT n=12 ICU mortality NIV Standard NIV Standard NIV independently associated to reduced risk for RF after extubation 3 2 1 p=.64 n=3 n=9 % 8 6 4 2 ICU mortality n=1 p<.1 n=2 Re-ETI No re-eti Re-IT strongly predicted mortality
Successful weaning trial (36% COPD or chronic bronchitis) Risk factors for RF after extubation % 3 2 1 Extubation failure 4 p=.22 n=13 NIV n=27 Control % p=.429 % 1 9 8 7 6 5 (n=113) 9-day survival Overall population p=.397 (n=162) 1 2 3 4 5 6 7 8 9 Days p=.6 NIV group Control group No hypercapnia Hypercapnia 1 1 9 8 7 6 5 1 2 3 4 5 6 7 8 9 Days % 9 8 7 6 5 (n=49) 1 2 3 4 5 6 7 8 9 Days
7% COPD or chronic bronchitis Successful weaning trial, hypercapnia while on spontaneous breathing % Respiratory failure after extubation 5 p<.1 4 3 2 1 n=8 NIV n=25 Control % 1 9 8 7 6 5 9-day survival p=.15 1 2 3 4 5 6 7 8 9 Days NIV group Control group
Why? Control group NIV group AJRCCM 26 24 48 72 Control group Lancet 29 NIV group 24 48 72 Time from extubation (hours)
Severely obese patients NIV 48 h after extubation, compared with historically matched controls (n=62+62) % 3 2 1 Respiratory failure p=.3 n=6 n=16 2 1 ICU length of stay p<.1 NIV Control 3 2 1 Hosp. mortality p=.17 n=8 n=15 Hypercapnic patients during SBT 6 4 2 Hospital mortality p=.3 n=4 n=11
Why such different outcomes in RF after extubation? Studies on prevention 1. Prophylactic NIV immediately after extubation 2. Higher proportions of chronic respiratory disorders (39% and 51%) 3. Ventilator specifically designed for NIV with high performance 4. Long-term experience (>1 yr) in clinical use and research with NIV 5. Scheduled periods of NIV delivery after extubation Studies on treatment 1. Therapeutic NIV after RF after extubation developed 2. Lower proportions of chronic respiratory disorders (COPD: 1-11%) 3. Ventilators with less performance or no specific ventilator 4. Minimal required experience with NIV of 1 year in both studies 5. After 4-12 h, no subsequent continuous delivery of NIV Nava S. Crit Care Med 25;32:2465 Ferrer M. Am J Respir Crit Care Med 26;173:164 Ferrer M. Lancet 29;374:182 Keenan SP. JAMA 22;287:3238 Esteban A. N Engl J Med 24;35:2452
Limitations of NIV in withdrawal of MV Main reasons for NIV failure Lack of co-operation, agitation Excessive secretions Hemodynamic instability Decreased consciousness (not hypercapnic) Protection of airways Tracheostomy?
NIV and respiratory failure after extubation Hypercapnia during spontaneous breathing trial is consistently associated with poor outcome In non-selected patients, NIV does not improve outcome of post-extubation failure and may be harmful In selected patients at high risk of re-intubation, it helps in preventing post-extubation failure Benefits of NIV in survival restricted to patients with hypercapnic respiratory failure