Presentation of Dr. Lluis Blanch at 10th Pulmonary Medicine Update Course, Cairo, Egypt. Pulmonary Medicine Update Course is organized by Scribe : www.scribeofegypt.com

1. Lluís Blanch M.D., Ph.D. Consultant Critical Care Scientific Director Corporació Parc Taulí Universitat Autónoma de Barcelona Sabadell, Spain. Cairo 3 - 4 February 2010 Weaning: Tips & Tricks 10th Pulmonary Medicine Update Course

2. Evaluating Patients to Be Wean from the Mechanical Ventilator A daily routine follow up should be done in every patient receiving mechanical ventilation and exploring the following condition: - stop sedation - resolution/improvement of the underlying disease - adequate gas exchange - core temperature below 38 ºC - stable hemodynamics with no need of vasoactive drugs - adequate performance of the respiratory muscles - no major metabolic and/or electrolitic disturbances - adequate mentation with no anxiety, fair or panic

3. Esteban A et al. Chest 1994; 106:1188 Modes of Mechanical Ventilation and Weaning A Cross-Sectional Multicenter Study in Spain Weaning: 41% of total ventilator time (59% in COPD)

4. Weaning Techniques: T-Piece SIMV PSV Weaning Approach: Team Based Physician Based

5. Esteban A et al. N Engl J Med 1995; 332:345. Comparison of 4 Methods of Weaning Patients from Mechanical Ventilation From 546 pts. who met weaning criteria, 100 pts. could not sustain 2 h SB were divided in 4 groups: Intermittent (24 h) Tpiece T piece or CPAP (2h) SIMV (5 b/min) PSV (5 cmH 2 O) Multiple or once-daily trial of SB led a quickly extubation compared with SIMV or PSV

6. Brochard L et al. Am J Respir Crit Care Med 1994; 150; 896. Comparison of 3 Methods of Gradual Withdrawal from Ventilatory Support during Weaning From 456 pts. who met weaning criteria, 109 pts. could not sustain 2 h SB were divided in 3 groups: T piece (2h) SIMV (4 b/min) PSV (8 cmH 2 O) Weaning duration and length of ICU were shorter with PSV

7. Effect of Spontaneous Breathing Trial Duration on Outcome A 30 minutes trial of spontaneous ventilation is as effective in identifying patients who could be safely extubated as a trial with a duration of 2 hours. Esteban A et al. Am J Respir Crit Care Med 1999; 159:512. n = 526 patients Successful extubation Reintubation Mortality Lenght of stay (ICU) d. Lenght of stay (HOSP) d. 205 (76%) 32 (13.5%) 34 (13%) 10 (6,18) 22 (15,33) 187 (73%)* 29 (13.4%) 22 (9%) 12 (7,21)* 27 (17,43) * 30 min . 2 hours

8. Ely EW et al. N Engl J Med 1996; 335:1864. Effect on the Duration of MV of Identifying Patients Capable of Breathing Spontaneously Intervention Group: daily screening + 2 h. T piece + notification. Control Group: daily screening A multidisciplinary management strategy promote earlier discontinuation of mechanical ventilation

10. Clinical Consequences of the Implementation of a Weaning Protocol Implementation of a weaning protocol reduces the duration of MV by increasing the number of direct extubations without using a weaning technique. Saura P, Blanch L et al. Intensive Care Med 1996; 22:1052. Direct extubation Extubations with weaning technique Weaning time (days) Duration of MV(days) ICU stay (days) 41 (80%) 5 (10%) 3.5+3.9 10.4+12 17+16 5 (10%) * 41 (80%) * 3.6+2.2 14.4+10.3 * 20+13 * Treatment Control

11. Weaning Techniques: T-Piece SIMV PSV Weaning Approach: Team Based Physician Based

12. Uchiyama A et al. Am J Respir Crit Care Med 1994; 150:1564. Diaphragmatic Activity in PSV and IMV A low IMV rate does not reduce diaphragmatic activity

13. Comparison of Closed-Loop Systems

14. Clinical Evaluation of a Computer-Controlled Pressure Support Mode Standard PSV Automatic PSV Unacceptable Ventilation: low, intermediate and high RR; low >VT; high PetCO 2 Dojat M et al. Am J Respir Crit Care Med 2000; 161:1161.

15. Am J Respir Crit Care Med Vol 174. pp 894–900, 2006 RCT 144 ICU pts. Mean MV duration 3.5 to 4 days 74 computer-driven weaning; 70 physician-controlled weaning CDW Evita 4 Usual Weaning CDW Evita 4 Usual Weaning Complications during MV Outcome

16. RCT 102 ICU pts. Mean MV duration 119 to129 hours 51 SmartCare/PS; 51 control (clinician PS & PEEP reduction) Reductions in weaning time were not confirmed when SmartCare/PS was compared to weaning managed by critical care nurses, using a 1:1 nurse/patient ratio. SmartCare/PS Control p Outcomes

17. 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

22. tachycardia intercostal recession supresternal & supraclavicular recession sternomastoid activity diaphoresis & nasal flaring cyanosis tachypnea abdominal paradox Tobin MJ. Principles and Practice of MV. 1994. Signs in a Patient who Fail the Weaning Trial

23. Tobin MJ et al. Am Rev Respir Dis 1986; 134:1111. Pathophysiologic Factors for Respiratory Distress during a Weaning Trial The pattern of breathing: rapid & shallow

24. Yang KL & Tobin MJ. N Engl J Med 1991; 324:1445. Ratio of Frequency to Tidal Volume 80% WS 95% WF

25. Extubation failure occurred in 121 of the 900 (13.4 %) … and pneumonia at initiation of MV were the best predictors of extubation failure

26. Jubran A & Tobin MJ. Am J Respir Crit Care Med 1997; 155: 906. Pathophysiologic Factors for Respiratory Distress during a Weaning Trial Respiratory mechanics: increase in autoPEEP and in resistance: inefficient CO 2 clearance

27. Lemaire F, Teboul JL, et al. Anesthesiology 1988; 69:171. Pathophysiologic Factors for Respiratory Distress during a Weaning Trial Heart & lung interaction: acute LV dysfunction

28. Jubran A et al. Am J Respir Crit Care Med 1998; 158:1763. Pathophysiologic Factors for Respiratory Distress during a Weaning Trial Tissue oxygenation: TO 2 EO 2 Elevations in right & left ventricular afterload n=11 n=8 ↑ SAP ↑ PCWP ↓ CI

29. Phychological Aspects of Weaning: 1- MV patients know that their ability to breath depends on help from a machine 2- ET tube makes hard to communicate 3- Inability to talk: anxiety, helpness, anger, despair, hopeless,… 4- Other stressors: dyspnea and sleep difficulties

30. Resistive Load Plotted Against Borg Scale of Breathing Difficulty & Mouth Pressure panic no panic Am J Respir Crit Care Med Vol 178. pp 7–12, 2008

31. Air Hunger Induced by Lowering Tidal Volume at PCO 2 41 J Neurophysiol 2002;88:1500-1511 Air Hunger Moderate Slight Zero 0 1 Tidal Volume 1.47 L 0.75 L 6 healthy subjects

33. Parthasarathy S, Tobin MJ. AJRCCM 2002;166:1423-9 H: PSV causes hypocapnia; lack of a back up rate and wakefulness drive leads to central apnea and sleep fragmentation. 11 Patients, PB 7200. ACV 8 VT ml/kg and rr 4 breaths below assisted rate. PSV for 8 ml/kg. PSV with 100 mL of added deadspace. E 30 cmH2O/L, R 14 cmH2O/L/s. PSV 17-20 cmH2O Same doses of sedatives between patients w and w/o apneas Effect of Ventilator Mode on Sleep Quality in Critically Ill Patients

34. Parthasarathy S, Tobin MJ. AJRCCM 2002;166:1423-9 Arousals and awakenings Sleep fragmentation, measured as number of arousals and awakenings, was greater during PSV than during ACV 79  7 vs 54  7 events/h, p=0.02

35. In Conclusion: 1- Successful weaning depends on skilled judgement, decision making, medical and nursing observation and intervention. 2- Most patients do not require prolonged period of withdrawal of MV. 3- Inadequate discontinuation of ventilatory support can precipitate, muscle fatigue, abnormal gas exchange and loss of airway protection. 4- Have in mind: sleep quality, mental status, ICU-adquired weakness and cardiac function. Weaning: Tips and Tricks