1. APPROACH TO ASSESSMENT AND WEANING AT THE BED SIDE
DR. ANKIT JAIN

2. When to wean?? I

3. When to wean?? Why was he ventilated??
Resolution/Reversal of Primary Pathology for which patient was ventilated.
Clinical Evidence.
Lab/Radiological Evidence.

4. Loss of airway protection
When To wean?
Early
Late
Impaired gas exchange
Fatigue
Loss of airway protection
Morbidity/Mortality
Sedation
Infection
Lung Injury

5. When to Wean?
Search and treat other causes that may contribute to ventilator dependence.
Know the causes of Ventilator Dependence/Failure to wean.
Especially true in pts on venti >24 hrs and failed SBT.

6. Factors in weaning failure

7. Causes of Ventilator Dependence and Failure to Wean
Causes of Respiratory Failure
Neurological Factors
Central
Stroke
Drugs
Electrolytes
Peripheral
Neuropathies/Myopathies
Respiratory Factors
Chest Wall
Parenchymal Disease
Airway Disease

8. Causes of Ventilator Dependence and Failure to Wean
Non Respiratory Factors.
Cardiac Factors
Acute LVF
Acid-Base Factors
Respiratory Alkalosis
Metabolic Acidosis
Metabolic Factors
Hypo PO4
Hypo Mg
Hypothyroid
Pharmacological Agents
Sedation
NMBA
Aminoglycosides
Nutrition
Malnutrition.
Overfeeding
Psychology

9. When to Wean?
Search and treat other causes that may contribute to ventilator dependence.
Know the causes of Ventilator Dependence/Failure to wean.
Structured bed side approach to identify these causes. (In Exam and in Clinical Practice.)
Especially true in pts on venti >24 hrs and failed SBT.

10. Bedside approach to identify these causes

12. Identify these Causes at the Bedside
Keep the Causes in Mind.
Structured Patient Examination
The Environment
Cubicle
Patient Monitor
Ventilator
Infusions
Equipment
Drains
Trends (Ask for in the Exam)
Investigations (Ask for in the Exam)

14. When to Wean?
Search and treat other causes that may contribute to ventilator dependence.
Know the causes of Ventilator Dependence/Failure to wean.
Structured bed side approach to identify these causes. (In Exam and in Clinical Practice.)
Treat these causes!
Especially true in pts on venti >24 hrs and failed SBT.

15. Certain measurable criteria to be fulfilled

16. Certain measurable criteria
Adequate Oxygenation
ABG
PaO2>60 with FiO2<0.4
PaO2/FiO2 >150
PEEP < 8 cm H20
pH >7.25
Hemodynamic Stability
Clinically no Hypotension
No or Low dose Vasopressors
(EXCEPTIONS TO THE CRITERIA)

17. “Supervised” Spontaneous Breathing Trial
III

18. “Supervised” Spontaneous Breathing Trial
When??
Everything okay uptill now. (Step I and II cleared)
Screening for few minutes
Extended SBT
Duration
30mins to 120 minutes
Mode
CPAP/PS
T-Piece
SIMV
Complex Modes
ATC, ASV, MMV

19. “Supervised” Spontaneous Breathing Trial
Factors Assessed
Respiratory Pattern
Tidal Volume
Respiratory Rate
Rapid Shallow Breathing Index (RSBI)
Reliable
RR (breaths per minute) /T V (Liters)
1 minute after Disconnecting
RSBI should be < 105
Normal 60 to 105
Complex Parameters (WOB, Dynamic Compliance, CROP index)
Adequacy of Gas Exchange
Monitor/SpO2
ABG
HD Stability
Subjective Comfort.

20. SBT FAILED
WHAT NOW??

21. Failed SBT Back to the Drawing board
Remember the Causes of Failure to Wean and How to identify them clinically??

22. Causes of Ventilator Dependence and Failure to Wean
Causes of Respiratory Failure
Neurological Factors
Central
Stroke
Drugs
Electrolytes
Peripheral
Neuropathies/Myopathies
Respiratory Factors
Chest Wall
Parenchymal Disease
Airway Disease

23. Causes of Ventilator Dependence and Failure to Wean
Non Respiratory Factors.
Cardiac Factors
Acute LVF
Acid-Base Factors
Respiratory Acidosis
Metabolic Acidosis
Metabolic Factors
Hypo PO4
Hypo Mg
Hypothyroid
Pharmacological Agents
Sedation
NMBA
Aminoglycosides
Nutrition
Malnutrition.
Overfeeding
Psychology

24. Failed SBT Back to the Drawing board
Remember the Causes of Failure to Wean and How to identify them clinically??
Identify and Treat these Cause.

25. Failed SBT No trial of SBT for another 24 hours
Even twice daily SBTs offer no advantage.
Do not reduce ventilator Support aggressively during these 24 hours.
No evidence that a gradual support reduction strategy is better than providing full stable support between once daily SBTs.

26. SBT Successful
WHAT NEXT??

27. SBT SUCCESFUL
Patient can be Weaned but…..
Can he be Extubated???