1. Weaning
RC 270

2. When is the time to consider weaning from the ventilator?
When the decision is made to ventilate the patient!

3. Weaning will be successful only if a potentially reversible disease process exits.
Barry Shapiro M.D.

4. Weaning: Physical Assessment
Stable ABGs on 50% or <
PNP (NIF) = -20 cmH2O or more –
Is not effort dependent
VC = 15 ml/kg
FEV1 = 10 ml/kg
Spontaneous Ve = 5 – 10 lpm
MVV = twice the spontaneous Ve
P0.1 = 4-6 cmH2O
RSBI [f/Vt (in liters)] < 105

5. Weaning: Gas Exchange Assessments
Vd/Vt no greater than 55-60%
A-aO2 on 100% no more than mmhg
%Shunt under 20%
P/F = 286 or >
PaO2/FIO2
FIO2 expressed as a decimal
200 or less = severe shunting

6. Weaning: Other Factors to Optimize
Acid-Base abnormalities
Anemia
Arrhythmias
Electrolyte imbalance
Energy/Nutritional status
Fever/Infection
Fluid Balance
Pain
Sleep deprivation

7. Classical Weaning Spontaneous Breathing Trial
If the patient appears ready to
wean, he is removed from the
Ventilator and placed on a
T-tube and monitored

8. Monitor and place back on CMV if:
BP increases/decreases 20 mmhg systolic or 10 mmhg diastolic
Heart rate increases/decreases 20 or more (or rate exceeds 110)
Respiratory rate increases by 10 or exceeds 30
Vt drops to less than ml
Arrhythmias develop
ABGs deteriorate (may also use pulse oximeter and capnograph)

9. The time is lengthened each time he is removed from the ventilator

10. Besides Classical Technique:
IMV
Pressure Support
MMV

11. The End