What is a bag valve mask?
Bag-valve-mask (BVM) or the Ambu bag is a self-inflating bag used to provide ventilation to the person not breathing normally.
Bag valve mask (BVM) ventilation is usually done in an emergency until intubation can be done.
A BVM consists of a non-rebreathing valve and a face mask. The opposite end of the bag is attached to an oxygen source. The mask is manually held against the face. The bag is squeezed to provide ventilation to the patient through the nose and mouth until the intubation can be done.
What is bag valve mask ventilation?
BVM ventilation is a critical skill for emergency providers. BVM ventilation is a technique that restores breathing in patients who are not spontaneously breathing. In most settings, a BVM is an emergency procedure carried to tide over until intubation is done.
Factors that can cause difficulty in BVM ventilation include:
What are the criteria for BVM ventilation?
Successful BVM ventilation depends on four things:
- An open airway: Any obstruction or blockage in the airway can affect the BVM ventilation
- Mask should be sealed adequately on face
- Proper ventilation technique
- Valve for proper oxygenation
When is the bag valve mask indicated?
BVM ventilation is indicated in the following conditions:
- Respiratory (lung) failure
- Failed intubation (insertion of an artificial ventilation tube into the trachea)
- Patients undergoing anesthesia for elective surgery
- Apnea (slowed or stopped breathing)
However, BVM should be avoided in the following situations:
How is bag valve mask ventilation carried out?
The patient is made to lie flat on the stretcher. The doctor tilts the head backward and lifts the chin. In patients with spinal injuries, head-tilting is avoided.
BVM ventilation is usually performed with two-rescuers.
The first rescuer places a mask on the patient’s face before attaching the bag and seals the nose and mouth with the mask.
The bag is squeezed manually by a second rescuer to transport oxygen via a mask or tube spontaneously to the patient.
A target rate of 10 ventilations per minute should be achieved during ventilation.
What are the complications of bag valve mask ventilation?
Complications of BVM ventilation include:
- Over-ventilating or hyperventilation: Giving too much volume of air or giving it too fast can result in pushing of air into the stomach, leading to a condition known as gastric insufflation.
- Aspiration (entry of foreign objects into the airway)
- Worsen the airway obstruction
- Accelerate hypoxia (low oxygen level in the blood)