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How does an Ambu Bag work? May 9,2019.

A bag valve mask, abbreviated to BVM and sometimes known by the proprietary name Ambu bag or generically as a manual resuscitator or "self-inflating bag", is a hand-held device commonly used to provide positive pressure ventilation to patients who are not breathing or not breathing adequately. Today we are going to take a closer look at how does this important medical device work by reviewing FirstCare’s Silicone Reusable BVM Mask.

How does an ambu bag work?

Intended Use

The FirstCare Solid Silicone reusable resuscitator is a self-inflating manual resuscitator that is intended for patients requiring total or intermittent ventilatory support. It provides positive pressure ventilation and allows spontaneous breathing with a face mask. Ventilation is possible with or without supplemental oxygen.

The FirstCare Reusable Resuscitator is available in three sizes:

The Adult model is intended for patients over 40 kg.

The Pediatric model is intended for patients from 10 kg to 40 kg.

The Infant model is intended for patients below 10 kg.

Product Overview:

Bag Valve Mask

Part Name



Anesthesia Mask


Neonate, Infant, Pediatric, Adult-S, Adult-M, Adult-L, Adult-XL

Mask Hook



Patient Connector


Patient Valve


Pressure Limiting Valve


Infant & Pediatric: 40cmH2O

Adult: 60cmH2O

Bag Connector


Resuscitation Bag


Intake Valve


Reservoir Bag


Oxygen Tube



The patient connector, patient valve and, pressure limiting valve, bag connector, and intake valve have already been well-assembled into PP box, please follow steps below to finish the assembly:

1. Stretch the foldable and space-saving resuscitation bag (adult & pediatric type) to the full extend and visually check the proper valve action while squeezing the bag;

2. Connect the anesthesia mask into patient connector via the mask outlet;

If external oxygen source like oxygen tank or cylinder is available, then:

3. Extend and connect the reservoir bag to the intake valve;

4. Extend the oxygen tube to the intake valve in one side and to the outer source in the other side. Set oxygen flow not to exceed 15 LPM or under the instruction of professionals.


1. Remove the anesthesia mask from the patient connector;

2. Unscrew the reservoir bag and oxygen tube from the intake valve;

3. Unscrew the patient valve and intake valve from the resuscitation bag;

4. Disintegrate the pressure limiting valve and patient valve connected to the patient valve;

5. Separate the lid from the patient valve;

6. The patient valve disk should not be separated from the patient connector.

7. The resuscitator (silicone mask, resuscitation bag and valves) can be autoclaved for up to 20 times only. Replace the reservoir bag and oxygen tube each time before reusing the resuscitator.

Pre-use Test

1. Resuscitation Bag

Connect a 1.5-liter test lung the to patient connector. Squeeze and release the resuscitator several times and make sure the test lung expands and deflate visibly and accordingly. If not, check the inlet shutter and the patient valve shutter.

2. Pressure Limiting Valve

Close the pressure limiting valve and patient connector with a thumb while compressing the resuscitator bag firmly to check the tightness and proper valve fitting;

Open the pressure limiting valve and close the patient connector with a thumb. The pressure limiting valve should be activated and it should be possible to hear the hissing expiratory flow from the valve.

3. Reservoir Bag

Supply a gas flow of 3.0 L/min to oxygen tube and check if the reservoir bag fills. If not, check if it is the problems of valve shutters, torn bag or blocked oxygen tube.

Neonate Ambu Bag

Operation Instruction

1. Open the patient’s mouth and clear all the airway excretions (apply emergency aspirator if available). Tilt the head fully backwards and push the jaw upwards with neck stretched to open the airway.

2. To assist ventilation, it may be beneficial to insert an artificial airway. Be careful that it does not push the tongue back and thus obstruct the throat.

3. Put the mask tightly to the patient’s mouth and nose with the thumb and index finger of the left hand pressed on it and the other three fingers keep the jaw upwards. Squeeze the ventilation bag properly and watch the chest expand.

4. Release the bag promptly and allow the chest to deflate. Repeat 12-20 times per minute or 30 times in case of infants.


1. The resuscitators should only be used by persons who have received adequate training in the use of resuscitators. You can find out more information about becoming a first aid responder in our blog.

2. If it fails to insufflate, check the airway obstruction or the head position.

3. If inadequate ventilation is achieved with the resuscitator, immediately turn to mouth-to-mouth or mouth-to-nose ventilation.

4. The correct ventilation frequency may vary. Please follow the current ventilation frequency recommended by national or international guideline.

5. If the patients vomit during the ventilation, immediately clear the patient’s airway and then squeeze the bag a few times before resuming ventilation.

6. The pressure limiting valve would open to certain extend and a hissing sound would be heard. If higher pressure is required, press and spin the button while squeezing the bag. The valve will then shut down.

7. The resuscitator (silicone mask, resuscitation bag and valves) can be autoclaved for up to 20 times only. Replace the reservoir bag and oxygen tube each time before reusing the resuscitator.

Cleaning and Disinfection

To reduce the risk of cross-contamination, follow these instructions after each use.

1.Inspection: Carefully inspect all parts for signs of wear or damage. Worn or damaged components must be discarded and replaced with new components.

2.Washing and Rinsing: The resuscitators must be cleaned before high-level disinfection or sterilization. They can be manually cleaned, or cleaned in an automatic washer/disinfector.

Manual Cleaning

Rinse parts under cold running water.

Submerge parts in water at 30 - 40 ºC (86 - 104 ºF). Ensure that all surfaces are submerged for at least 2 minutes.

Submerge all parts in water at 60 - 70 ºC (140 - 158 ºF) which contains dish

washing detergent.

Thoroughly clean all surfaces using a brush as necessary.

Rinse all components in detergent-free water at 30 - 40 ºC (86 - 104 ºF).

Dry the components thoroughly. Inspect all components to confirm that they

are clean and dry. If parts are worn or damaged, discard them.

Automatic Cleaning Washer/Disinfector (applies to all parts except Reservoir Bags)

Place parts in wire baskets.

Cycle 1: 90 - 95 ºC (194 - 203 ºF) for more than 12 seconds.

Total process time: approx. 52 min.

Cycle 2: Use a Non-enzymatic alkaline detergent containing 2 - 5% NaOH.

3. Sterilization: To obtain sterilization of the resuscitator, follow method below


Process Parameters



Exposure time

Steam Autoclaving


Autoclave at

132 - 137 ºC

(270 - 279 ºF)

15 min

(+ 30s)

Allow parts to

cool and dry

Steam Autoclaving


Autoclave at

134 - 137 ºC

(273 - 279 ºF)

3 min


If you are interested in acquiring the full details of FirstCare’s user guide on manual resuscitators including technical data sheet, you can go to our Downloads page on this website or contact us by

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