![What are the final lessons?
“Weanable” patients should undergo a
30 minute T-piece trial
[PS (7 cm H20) is acceptable]
Once a day T-piece trial is enough
Bon Jour…
Que?](https://image.slidesharecdn.com/weaningfinal3-220930013141-b848c8f0/85/Weaning-final-3-ppt-24-320.jpg)
![Take Home
Parameters predict failure better than
success
“Weanable” patients should undergo a
30-minute T-piece trial. [PS (7 cm H20) is
acceptable]
Weaning by Protocol is useful
Consider NiPPV / CPAP as an effective
weaning tool
Early tracheostomy enhances wean
(Chest 2001; 120: 425S-437S)](https://image.slidesharecdn.com/weaningfinal3-220930013141-b848c8f0/85/Weaning-final-3-ppt-39-320.jpg)
Weaning final (3).ppt
- 1. Weaning from Mechanical Ventilation
- 2. What is weaning? It starts when the clinician “decides” that the patient may tolerate a reduction of mechanical support It includes methods used for a stepwise reduction in the level of support & “readiness testing” of the ability of the patient to sustain spontaneous breath
- 3. Determine readiness for weaning Weaning parameters Physiological parameters Indices How to wean Sedation management Mode Protocolised Difficulty in weaning Tracheostomy How to wean???
- 4. From the desk of: George W. Bush Jr. President, World USA October 2002 Check list for Iraqi Invasion Guns Missiles Nuclear Devices Mercenaries Poison gas Map of Iraq Tony Blair’s OK Tanks Soldiers A reason Readiness to wean…
- 5. Deciding to initiate wean Objective criteria: Adequate oxygenation (P/F > 200, PEEP<5) Stable CVS (BP, pressors, HR) Adequate cough reflex Adequate mentation (GCS>12) ? Rapid-shallow breathing index <105 Subjective criteria: Resolution of disease Physician feels that discontinuation is possible Chest 2001; 120:375S–395S
- 6. All attempts are NOT likely to succeed…. but can we predict which will?
- 7. Weaning Parameters CAPACITY Tidal volume Max VV Vital Capacity Negative Insp. Press. Lung Mechanics NEED Minute volume Work of Breathing Pressure-time index NEED vs. CAPACITY Respiratory Rate Rapid-shallow Br. Index MULTIVARIATE RBSI / Occ. Pres.
- 8. Rapid Shallow Breathing Index The breathing pattern in respiratory failure is characterised by: Low Tidal volumes (shallowness) & High respiratory rate (rapidity) e.g.: RR = 25, Vt = 300 ml RSBI = 25/.3 = 83; Passed test RR = 40, Vt = 200 ml RSBI = 40/.2 = 200; Failed test
- 9. The value of ‘Weaning’ Parameters Most Weaning Indices predict weaning failure well but…. do not predict successful weaning
- 10. Steps for weaning Sedation Management Estimate likelihood of success Physical exam “Parameter” measurement Secretion load Cough Spontaneous breathing trial (SBT) Extubation Post-extubation care and monitoring
- 11. Sedation Management Big hurdle in the weaning process Daily conscious titration of sedation necessary Drug choice Duration of action Duration of sedation Sedation titration Management of anxiety and pain
- 12. Sedation: Daily Discontinuation Routine Sedation Daily d/c RCT; 128 adults on ventilation N Engl J Med 2000;342:1471-7.
- 13. Sedation Management Decreased incidence of complications of critical illness in the daily interruption group Schweikert WD et al Crit Care Med. 2004 Jun;32(6):1272-6 No increased incidence of Myocardial ischemia Post-traumatic stress disorder after ICU stay
- 14. Weaning Modes Spontaneous breathing trial (SBT) T-piece or CPAP 5/5 trial Assess readiness for weaning Weaning SIMV Decreasing mandatory breath rate PSV Gradual decrease in PS
- 15. What mode to use? Limited information from clinical trials Inadequate power Patient heterogeneity Patient readiness Definition of successful weaning In summary T-piece and PSV superior to SIMV T-piece equivalent to PS 5/5 trials T-piece vs. PS wean
- 16. Methods: Spontaneous Breathing trials Abrupt cessation of support and placement on a “T-piece” or Allowing breathing on the ventilator -providing only low C-PAP (5 cm H20) & / or Pressure Support (5-7 cm H20) Oxygen Source
- 17. T-piece vs. Pressure Support Breathing spontaneously through a T- piece & ET tube J respiratory load Added pressure support may overcome work imposed by tube resistance & demand valve. However…., in some critically ill patients post-extubation loads may be greater than while intubated So which mode is better? VS. Chest 1993; 103: 1215-1219 Chest 1995; 107: 204-209
- 18. Pressure Support vs. T-piece Pressure Support (7 cm H20) 86% 14% Extubated Failed T-piece for 2 hours 78% 22% p = 0.02 Pressure support increases extubation rates without increasing the frequency of re-intubation No difference in LOS, mortality. 63% of T-pieced and 70% of PS patients remained extubated (NS) Esteban et al. AJRCCM 1997;156:459-465
- 19. Long vs. short T-piece trials Esteban et al. AJRCCM 1999;159:512-518 10 12 22 27 0 5 10 15 20 25 30 ICU LOS Hospital LOS 30 minute 120 minute p 0.02 p <0.01 Rationale: 2-hour trials may be too long; Median time for trial failures is < 30 minutes No difference in mortality, extubation or re-intubation rates
- 20. Brochard et al 1994 109 patients of 456 patients failed initial T-piece trials Further weaning compared 3 strategies Pressure support wean Spontaneous breathing trials (T-piece) • Up to 3 two-hour trials per day AJRCCM 1994; 150: 896-903 Oooh… mon dieu!!
- 21. Brochard et al 1994 17.5 26.8 28.9 0 5 10 15 20 25 30 Days ICU LOS PS IMV T-piece p <0.01 p 0.02 136.8 237.6 204 0 50 100 150 200 250 Hours Weaning time p 0.08 p 0.01 No difference in mortality, extubation, re-intubation, CV, pneumonia rates.
- 22. Spanish Collaborative Trial Similar design; on 130 of 546 patients who failed initial T-piece Compared T-piece breathing once a day • 2 hour trials T-piece multiple times Pressure support • Reduced by 2-4 cms at least twice a day • Extubated if tolerating 5cms for 2 hours NEnglJMed 1995;332; 345-50. Ai…ai…ai!!
- 23. Spanish Collaborative Trial Intermittent T Once a day T Press. Support IMV 2 4 6 8 10 12 14 Duration of Wean (days) Probability Of Successful Wean 1 0.5 0 Adjusted RR of wean by T-piece 2.83 x IMV (95% CI = 1.36-5.89) 2.05 x PS (95% CI = 1.04-4.04) NEnglJMed 1995;332; 345-50.
- 24. What are the final lessons? “Weanable” patients should undergo a 30 minute T-piece trial [PS (7 cm H20) is acceptable] Once a day T-piece trial is enough Bon Jour… Que?
- 25. Observation During Weaning DISTRESS PARAMETERS High Respiratory Rate Respiratory pattern (paradox, nasal flaring) Low Tidal Volume Drop in oxygen saturation <90% Increased heart rate (> 20% from baseline) High blood pressure Anxiety, agitation, diaphoresis Somnolence
- 26. Summing up the Approach “Ready to wean” 2/3 weaned Initial T-piece 1/3 not weanable Daily T Pres. Sup 85-90% weaned in 14 days “Difficult-to-wean” (~3-5% of all cases) (High resource use; up to 75% mortality) AJRCCM 2001; 164: 186-7
- 27. Protocolized weaning: (C)lean, Mean Guarantees of Success? Does the application of nurse/ respiratory care professional directed weaning trial improve outcome? Removes uncertainty and delays involved with physician-centered decisions. ears neck feet
- 28. Approach to failed initial trials About ¼ of “ready-to-wean” patients will fail the initial spontaneous breathing trial Should such patients Be evaluated by repeated spontaneous breathing trials or By gradual “reduction” of ventilatory assistance using IMV / Pressure support Oooh… my God!!
- 29. Reasons for Failure Reduced respiratory drive; CNS, encephalopathy, sedation. Persistent respiratory abnormality Persistent muscular weakness Persistent load on respiratory system; tubing size, length, humidifiers Poor cardiac reserve Iatrogenic; underfeeding, electrolyte imbalance, etc. ? Psychological; anxiety, fear
- 30. Defining “Difficult-to-wean” “Ready to wean” 2/3 weaned Initial T-piece 1/3 not weanable Daily T Pres. Sup 85-90% weaned in 14 days “Difficult-to-wean” (~3-5% of all cases) (High resource use; high mortality) AJRCCM 2001; 164: 186-7 * Chest 2005; 128: 3937-54 Consensus Definition* “Prolonged Mechanical Ventilation” (PMV) is the need of MV >21 days for >6 hours /day In acute cases on MV ~25% need MV > 7days 3-7% need MV >21 days
- 31. Reasons for Failure Presume correction of primary disease especially of lung disease Neurological control Respiratory load Cardiovascular tolerance Motor function
- 32. Extubation Failure: Extubation failure occurs at rates of between 2-20% (of extubated patients). Affected by: Age: Elderly Gender: Male? Disease process (Neuro. vs. COPD vs. Cardiac) Medical (vs. Surgical) patients Duration of ventilation before weaning trial Sedation Severity of illness does not seem to correlate Epstein SK, Resp Care Clin NA 2000; 6:321-60.
- 33. Extubation failure: Outcomes “Let’s pull the tube to see how it goes!” presumes no negative outcome with failed extubation But….. Multivariate analysis of outcomes in trials of extubation show that patients who needed re-intubation were 10 x as likely to die as successfully extubated patients Epstein SK, Resp Care Clin NA 2000; 6:321-60. & Esteban A et al, AJRCCM 1997;156:459-465
- 34. Come on! It can’t go wrong every time… So, what should we be looking for in jumpi… weaning?
- 35. Non-invasive Support in Weaning p <0.01 15 24 0 5 10 15 20 25 Days ICU LOS NiPPV PS+/- CPAP p 0.02 245 398 0 100 200 300 400 Hours Duration of Ventilation Ann Int Med 1998; 128: 721-8 In COPD patients; 60-day mortality & nosocomial pneumonia showed improving trends
- 36. Routine NiPPV Weaning? p 0.003 9.5 20.1 0 5 10 15 20 25 % Ventilator Days NiPPV Routine Ferrer; AJRCCM 2003;168:70–76 A heterogeneous group of patients who failed multiple daily t- piece trials Unfortunately ¾ had COPD even in this study
- 37. Tracheostomy? Chest 2001; 120:477S–481S Improved comfort of caregiver (Doctor / nurse vs. patient) Airway mechanics Less Resistance Increased turbulence benefit on wean duration
- 38. BMJ 2005; 330: 1243 8.5 fewer days on ventilator Is there evidence?
- 39. Take Home Parameters predict failure better than success “Weanable” patients should undergo a 30-minute T-piece trial. [PS (7 cm H20) is acceptable] Weaning by Protocol is useful Consider NiPPV / CPAP as an effective weaning tool Early tracheostomy enhances wean (Chest 2001; 120: 425S-437S)