WEANING The Discontinuation of Ventilatory Support

By Adriana Adams and Cesar Mancillas

What is Weaning?

• Weaning is the gradual decrease in the transitional process from total ventilatory support to spontaneous breathing.

Reasons for Mechanical Ventilation

• RESPIRATORY FAILURE SECONDARY TO:• Hemodynamically Unstable• Airway Protection• Neuromuscular Disorders• Inadequate Ventilatory Capacity

Methods of Weaning

• SIMV/CPAP Mode• PSV

• T-tube/ATC

DAILY SCREENING• Resolved/Improved

underlying problem• Awake, oriented,

Responsive• Able to Cough• Adequate gas

exchange• Off Sedations,

vasopressor

• Adequate hemoglobin levels

• Hemodynamically Stable

• Airway Patency• Ventilation

Pump/Capacity adequacy

Airway Patency Parameters

• Maximal expiratory pressure• Peak Expiratory Flow • Cough Strength• Secretion volume• Suctioning frequency• Cuff leak test • Neurological Function(GCS):

Physiological Parameters

• Rate: <35bpm• Maximal Inspiratory Pressure: < -

20cmH2O• RSBI: r/Vt= <100b/min• Vital Capacity: <10-15mL/kg(<15L/min)

Adequate Oxygenation Parameters

• PaO2: >60mmHg(at FiO2 of 50%)

• PEEP: <5-8cmH2O• PaO2/FiO2:

>200mmHg• PaO2/PAo2: >0.50• P(A-a)O2:

<350mmHg (FiO2max1)

• %Qs/Qt: <20%• pH: >7.25• PaCO2: Normal

Level• SaO2: >90%• Hgb: 8-10g/dl

Ventilatory Pump Parameters

• Vt: >350ml(>4ml/kg)• Cd: >25ml/cmH2O• Cs: >35ml/cmH2O• Ve: <10L/min• Vd/Vt: <60%

SIMV PROTOCOL• INITIAL SETTINGS

• RR: 8/min( <2-4bpm/hr at least BID) until pt is stable at 0-5bpm for 2hrs.

• PS: 25cmH2O(<2-4/hr) until pt is stable at 0-5cmH2O/min for 2hrs, followed by extubation.

• *If no resp. disorders, use half hour intervals.

• *Changes are made as tolerated by patient.

T-PIECE Weaning• Pt may be removed from ventilator or use CPAP• T-Piece Trials: Progressive increase in length of time

without ventilator support.(increments of 5-10min, then place back on ventilator for remainder of the hour.

• Until pt is off the vent for 30 min. on and off for 30 min, and so on.

• Use heated humidifier at desired FiO2(If 50%, consider extubation)

• If stable for 2hrs, consider extubation.• Advantage CPAP use: available alarms, apnea back up

settings, and able to monitor patients ventilatory capacity.

Recognizing Weaning Failure

• Tachypnea(>35bpm for >5min)• Hypoxemia(<90% saturation)• Tachycardia(>140bpm)• Bradycardia(If <heart rate by 20%)• Hypertension(>180mmHg)• Hypotension(<90mmHg)• Agitation, diaphoresis, anxiety, signs of >WOB

Ventilator Management Algorhythm

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EXTUBATION VIDEODo not try this at home kids!!!

The End!