1. Trouble Shooting (Mechanical Ventilation)
Arthur Sadhanandham
Medical ICU, CMC.

2. ‘WHEN NOAH BUILT THE ARK
IT WAS NOT RAINING’

3. Precautions that would reduce troubles
I. Power:
Plug into a grounded AC power with correct voltage receptacle.
Secure the power cord properly.
Battery Back up:
Check the battery level before connecting.
Charging should be carried out regularly.
Remember it is for short term use.

4. II. Gas Source Preferable to have centralised supply.
If cylinders used, should be full
Spare cylinders should be available.
Gas hoses should be in good condition.
Hoses – not contaminated with grease or oil (combustible)
Availability of compressors should be ensured.
Gases should remain dry and clean.

5. III. Personnel Properly trained personnel should only use.
Familiarising staff with operator’s manuel before using on a patient.
(One manufacturer’s manual may not exactly match with other brands).
Appropriate monitoring the functioning state of the ventilator while in use.

6. Contd… Familiarizing staff with alarm system.
Do not place ventilators in a combustible or explosive environment.
Do not use with flammable anaesthetic agents such as nitrous oxide and ether.

7. IV Servicing and Testing
Qualified personnel should undertake servicing.
Ventilator housing should not be opened while it is still connected with power.
Follow the specifications mentioned in the service manual.
Use replacement parts supplied by the manufacturer only.

8. Contd…. General servicing at regular intervals should be done.
Run the prescribed tests and calibrations before using the ventilator on a patient.
Ensure that the ventilators pass all the tests before putting them in to clinical use.

9. ALARMS
All ventilators are equipped with visual and audible alarms which notify the user problems.

10. Points to remember Never ignore an alarm.
Never mute the alarm on regular basis.
Find out for yourself what alarm is on.
Check the patient.
Silence the alarm.

11. Act Swiftly
Depending upon the patient’s status and nature of the alarm, act appropriately.
This includes disconnecting the ventilator and connecting another means of ventilation to patient – Bain’s/ Ambu.

12. Do not forget
The use of an alarm monitoring system does not give absolute assurance of warning for every form of trouble that may occur with the ventilator.

13. Do not be like this !
But hear the alarm and respond See the problem and Ask if you do not know what to do

14. Common Troubles and Shooting
Ensure Alarm knobs / switches are turned on and functional.
Alarm
Cause
Shooting
Apnoea
No breath was delivered for the operator set apnoea time in spont, SIMV, AC, CMV & NIV modes
Because spontaneous Ventilation is too high or patient effort is too minimal
Trigger level set improperly.
Check the patient- Arouse if needed
Activate back up facility if it was not done already.
Consider switching over to any mandatory mode
Or go up on rate
Set trigger level appropriately

15. Low SpO2
Air / O2 Blender continuous
alarm
Delivery of O2 : FiO2, PEEP
High resistance
due to various
clinical reasons
Supply pressures
are inadequate.
Disconnect patient
from ventilator
Manually bag with
Bain’s and Ambu.
Insert the gas hose
fittings (air & O2)
correctly into the wall
outlets.
Ensure wall outlets
has adequate
pressure

16. The measured PIP is lesser than the set minimum level because of
Low pressure or
Low min.Vent Or
Low exhaled volume or
Disconnection
The measured PIP is lesser than the set minimum level because of
cuff leak.
Leak in the
circuit
Connections
may be loose
ET tube
displacement
Inadequate
flow
Evaluate cuff pressure
at regular intervals.
Reinflate if leak /
ruptured is noticed –
change ET tube.
Check circuits, junctions-
tighten or replace.
Check water traps
Check ET tube
placement. Position it
properly.
Reconnect ventilator.
Patient may require
higher flow.

17. High Pressure Alarm
The measured peak inspiratory pressure is great than set level because of
Secretions in airway
Partial block – (ETt)
Kinking of tube
Biting the tube
Water in the tube
Cuff herniation
Deep Rt. sided
intubation
Fighting the
ventilator
Suctioning, Irrigation
Release tubings
Bite block insertion
Empty the tubings and
water traps
Deflate & reinflate cuff
3-4 times
Reposition the ET tube
Reposition the patient
Re assurance
Sedation &
medication (pain)

18. High pressure alarm
Cough
Increased airway
resistance or
decreased
compliance
because of
Bronchospasm
Atelectasis
Fluid overload
Pneumothorax
Medication
Bronchodilators
Adjust the settings
VT &  Rate
VT  Rate,  PEEP
(Peak pressure to be monitored)
Immediate intervention

19. Auto Cycling
High Tidal Volume
Leak & Improper trigger setting
Patient trying to take more volume of air
Secure all
tubings tight
Set proper
trigger level
Increase flow
rate or
Increase tidal
volume

20. Trouble shooting!
THANK YOU FOR YOUR PATIENT HEARING