The document discusses guidelines and recommendations for weaning patients from mechanical ventilation and discontinuing ventilator support. Some key points covered include: - Weaning involves gradually reducing ventilatory support as a patient's condition improves to avoid complications of prolonged ventilation. - Readiness for weaning depends on recovery from the underlying medical issues, overall clinical condition, and psychological state. - Spontaneous breathing trials are recommended to assess a patient's ability to breathe independently without ventilator support. - Factors like ventilator mode, oxygen needs, airway protection, and non-respiratory medical conditions must be considered during the weaning process. - Protocols and guidelines aim to standard

1. WEANING AND
DISCONTINUATION
FROM
MECHANICALVENTILATION
Dr.K.Sivaraj
Respiratory Medicine PG
ASRAM

2. DEF:
 Gradual reduction of ventilatory support from a patient whose condition
is improving.
 Other terms
 Discontinuation
 Gradual withdrawl
 Liberation

3. Disadvantages of prolonged ventilation
 Nosocomial Pneumonia (VAP)
 Stretch injury and barotrauma
 Airway trauma
 Prolonged Sedation
 Obvious increase in associated cost
 Ventilator dependency

5. Decision to wean
 recovery from the medical problems thatimposed the need for mechanical
ventilation.
 Overall clinical condition.
 Psychological state

6. Premature withdrawl
 Ventilatory muscle fatigue
 Compromised gas exchange
 Loss of airway protection

7. Weaning techniques
 About 80% of patients requiring temporary mechanical ventilation do not
require a gradual withdrawal process, and can be disconnected within a few
hours or days of initial support.
 First : patients may require ventilatory support during weaning.
 Second : Second, supplemental oxygen and positive end-expiratory pressure
(PEEP) may be required to support oxygenation.
 Third : some individuals may require maintenance of the artificial airway even
after ventilatory support has been discontinued.
 Fourth : many patients require more than one of these therapeutic
interventions.

8. METHODS OF TITRATING VENTILATOR
SUPPORT DURING WEANING
 intermittent mandatory ventilation (IMV)
 Pressure support ventilation (PSV)
 T-piece weaning
 weaning process was inordinately prolonged with IMV compared with other
weaning techniques.

9. Closed loop ventilation
 volume-targeted PSV (e.g., volume support),
 Automode
 mandatory minute ventilation (MMV),
 automatic tube compensation
 artificial intelligence systems

10. Components of Ventilatory
Management and Discontinuation
 • Positive pressure ventilation (PPV) to support breathing
 • Supplemental oxygen and positive end-expiratory pressure (PEEP) to
improve oxygenation
 • Artificial airway to protect the airway and to provide
invasive ventilation
 • Airway management to maintain clear airways (i.e.,
suctioning; humidification and warming of inspired air;
bronchial hygiene; and aerosolized medications)
 • Therapy directed at the primary disease process

11. Intermittent mandatory
ventilation (IMV/SIMV)
 PSV can be added to unload
the spontaneous breaths and
reduce the patient’s WOB
through the ventilator system,
circuit, and artificial airway ,
which in turn can help prevent
excessive fatigue. (5
to 10 cm H2O)
 PEEP (5 to 10 cm H2O)

14. Pressure support ventilation
 PSV- patient triggered, pressure limited and flow cycled.
 5 to 15 cm of H2O
 When pressure support is reduced to about 5 cm H2O, the pressure level is
not high enough to contribute significantly to ventilatory support

15. T- Piece Weaning

16. CLOSED-LOOP CONTROL
MODES FOR
VENTILATOR
DISCONTINUATION

17. Automatic Tube Compensation
 Therefore a fixed level of pressure support can result in too little support when
inspiratory flow is high, or too much support when inspiratory flow is low.
 variable PSV with variable inspiratory flow compensation.

18. Volume-Targeted Pressure Support
Ventilation
 Volume support ventilation.
 It is a spontaneous mode.
 the operator sets the VT and the upper pressure limit

19. Automode and Variable Pressure Support/
Variable Pressure Control
 Usefull in a postoperative patient is still recovering from the effects of anesthesia
 ventilator operator has selected volume-controlled continuous mandatory
ventilation (VC-CMV) with automode as the operating mode, all breaths are
mandatory (time triggered, volume limited, and time cycled).
 If the patient begins to trigger breaths, the ventilator switches to VS (patient
triggered, pressure limited, and flow cycled with a volume target) and remains in
this mode as long as the patient is breathing spontaneously.

20. Mandatory Minute
Ventilation
 the ventilator adjusts the pressure,
frequency, or the VT to maintain the
desired VE.
With traditional weaning methods (e.g.,
IMV and PSV), a
constant level of ventilation is not
guaranteed.
As a precaution,
the high respiratory rate (f) and low VT
alarms must be set appropriately.

21. Artificial Intelligence Systems
 to maintain the patient in a respiratory “zone of comfort.
 The patient’s readiness for extubation is based on achieving the
predefined lowest level of inspiratory pressure.

22. Evidence-Based Weaning

23.  clinicians. In 1999 the federal Agency for Healthcare Policy and Research
(AHCPR) asked the McMaster University Outcomes Research Unit
to do a comprehensive review of the literature on ventilator withdrawal
issues to establish the evidence on which ventilator weaning is based.
 a task force of the ACCP, the SCCM, and the AARC created evidence-based
guidelines for ventilator weaning for patients requiring more than
24 hours of ventilation.

24. EVALUATION OF CLINICAL CRITERIA
FOR WEANING
Three key points have evolved as criteria for weaning:
 1. The problem that caused the patient to require ventilation must
have been resolved.
 2. Certain measurable criteria should be assessed to help establish
a patient’s readiness for discontinuation of ventilation.
 3. A spontaneous breathing trial should be performed to firmly
establish readiness for weaning.

26. RECOMMENDATION 1: PATHOLOGY
OF VENTILATOR DEPENDENCE

29. Patient-Ventilatory Performance and
Muscle Strength
 These include vital capacity (VC), VE, f, spontaneous VT, and the rapid shallow
breathing index (RSBI).

31. Measurement of Drive to Breathe
 To obtain the P0.1, the airway is occluded during the first 100
milliseconds of inspiration and the pressure at the upper airway is
measured (Fig. 20-6). The P0.1 is believed to reflect both the drive
to breathe and ventilatory muscle strength.2 The normal range is
0 to −2 cm H2O.

32.  A properly monitored SBT is safe and effective; therefore the other assessments
listed under Recommendation 2 (see Box 20-4) and in Table 20-1 may generally be
unnecessary.

33. RECOMMENDATION 3: ASSESSMENT DURING
A SPONTANEOUS BREATHING TRIAL
 “The best indicator of ventilator discontinuation potential is the clinical assessment
of patients during the 30- to 120-minute spontaneous breathing trial (e.g.,
respiratory rate, BP, HR, comfort/anxiety, oxygenation, SpO2).
 Studies have demonstrated that 77% to 85% of patients who pass an SBT can be
successfully weaned and extubated without requiring reintubation.
 The SBT can be accomplished using a low level of CPAP (e.g., 5 cm H2O), a low
level of PSV (e.g., 5 to 8 cm H2O), ATC, or simply a T-piece.

35. RECOMMENDATION 4: REMOVAL
OF THE ARTIFICIAL AIRWAY
 Some practitioners equate ventilator liberation with extubation .
 The cuff leak test is a means of testing for post extubation airway patency.
 Treatment with steroids or racemic epinephrine (or both) before extubation may
be indicated.
 an extubation failure rate of 10% to 19% may be clinically acceptable.
 Reintubation is marked by an eightfold higher risk for the development of
nosocomial pneumonia and a sixfold to twelvefold increase in the mortality rate.
 Interestingly, up to 80% of patients who intentionally self-extubate do not require
reintubation.

36. Postextubation Difficulties
 Hoarseness, sore throat, and cough are common after extubation. Other
postextubation problems include subglottic edema, increased WOB from
secretions, airway obstruction, and postextubation laryngospasm.
 Subglottic edema - nebulized racemic epinephrine (0.5 mL, 2.25% epinephrine in
3 mL normal saline).
 WOB – heliox therapy.
 Laryngospasm – positive pressure delivered with oxygen
 Non invasive Positive Pressure Ventilation After Extubation.

37. RECOMMENDATION 5: SPONTANEOUS
BREATHING TRIAL FAILURE
 Clinicians should wait 24 hours before attempting subsequent spontaneous
breathing trials (SBTs) in patients for whom SBT fails.
 Even twice-daily SBTs offer no advantage over testing once a day.
 NONRESPIRATORY FACTORS THAT MAY COMPLICATE WEANING

38.  Cardiac factors

39.  acid- base factors

40.  Metabolic factors
 hypophosphatemia, hypomagnesemia, and hypothyroidism – decrease muscle
strength.
 Effect of Pharmacologic Agents
 use of sedatives, opioids, tranquilizers, and hypnotic agents can all depress the
central ventilatory drive.
 The two primary reasons for prolonged paralysis after withdrawal of NMBAs are:
 (1) a reduced ability to metabolize and excrete these drugs and
 (2) the development of an acute myopathy.
 An acute myopathy can develop when high maintenance doses of corticosteroids
and continuous nondepolarizing agents (e.g., vecuronium or pancuronium) are
used.

41. Nutritional Status and Exercise
Increased minute ventilation
Increased carbondioxide production
Increase in oxygen consumption
Overfeeding carbohydrates

42. Psychological Factors
 Unmotivated patients therefore probably will take longer to wean than those
patients who are optimistic about their recovery.
 Psychological problems can manifest as fear, anxiety, delirium, ICU psychosis,
depression, anger, denial, fear of shortness of breath, and fear of being left alone,
among other symptoms.
 Health care workers often go into patient areas and perform a clinical procedure or
check the equipment and never take the time to communicate with the patient.
Establishing effective communication skills is critical for achieving successful
clinical outcomes.

43. RECOMMENDATION 6: MAINTAINING
VENTILATION IN PATIENTS WITH
SPONTANEOUS BREATHING TRIAL FAILURE
 Patients for whom an SBT fails should receive a stable, non fatiguing,
comfortable form of ventilatory support.
 To date there is no evidence that a gradual support reduction strategy is better
than providing full, stable support between once daily SBTs.

44. RECOMMENDATION 7: ANESTHESIA AND
SEDATION STRATEGIES AND PROTOCOLS
 A lower anesthetic/sedation regimen may permit earlier extubation.

45. RECOMMENDATION 8: WEANING
PROTOCOLS
 Protocols for ventilator discontinuation, which are designed for nonphysician
clinicians often are called therapist-driven protocols (TDPs) or nurse-driven
protocols.
 Weaning protocols have been shown to be efficient and effective approaches to
discontinuation of ventilatory support.

47. RECOMMENDATION 9: ROLE OF
TRACHEOSTOMY IN WEANING
 The procedure usually is performed within 7 days of the onset of respiratory
failure, or sooner in neurologically impaired patients.
 A tracheostomy site typically requires 7 to 10 days to mature. If the tracheostomy
tube is inadvertently displaced in the first 24 to 72 hours, successful blind tube
replacement is highly unlikely.

48. RECOMMENDATION 10: LONG-TERM CARE
FACILITIES FOR PATIENTS REQUIRING
PROLONGED VENTILATION
 exists, a patient who requires prolonged ventilatory support should not be
considered permanently ventilator dependent until 3 months have passed and all
weaning attempts during that time have failed.

49. RECOMMENDATION 11: CLINICIAN
FAMILIARITY WITH LONG-TERM
CARE FACILITIES
 These facilities should have demonstrated competence, safety, and success in
accomplishing ventilator discontinuation.

50. RECOMMENDATION 12: WEANING
IN LONG-TERM VENTILATION UNITS
The following are the goals for weaning in long-term care facilities.
1. To reduce the amount of ventilatory support
2. To reduce the invasiveness of support
3. To increase independence from mechanical devices
4. To preserve and/or improve current function
5. To maintain medical stability

51. ETHICAL DILEMMA: WITHHOLDING
AND
WITHDRAWING VENTILATORY
SUPPORT

52. “I believe that a skilled clinician at the bedside
does more to facilitate ventilator weaning than
any ventilator mode.”

53. THANK U