Bag mask ventilation, often referred to as BVM, is a fundamental method of emergency breathing support. It manually assists or delivers breaths to individuals with inadequate or absent breathing. It is a primary first aid intervention, maintaining oxygen flow until advanced medical care arrives.
Understanding Bag Mask Ventilation
The bag mask ventilation device consists of a self-inflating bag and a face mask that fits over the mouth and nose. A rescuer manually squeezes the bag, forcing air into the patient’s lungs. This ensures oxygen reaches the bloodstream when respiratory efforts are insufficient or absent.
It is necessary in urgent scenarios like respiratory arrest (ceased breathing) or severe breathing difficulties (e.g., choking, overdose). It is also used during cardiopulmonary resuscitation (CPR) to provide ventilations alongside chest compressions. Its straightforward design allows for quick application in emergencies.
Ventilation Rates for Different Situations
The frequency of breaths varies by patient age and whether chest compressions are performed. For adults receiving rescue breaths without chest compressions, the rate is one breath every 5 to 6 seconds (10-12 breaths per minute), allowing time for exhalation.
During adult CPR, the ventilation rate follows a 30 compressions to 2 breaths ratio. After 30 compressions, two slow, steady breaths are given, and compressions resume immediately. This ensures both blood circulation and oxygen delivery.
For children and infants, the breathing rate for rescue breaths alone is slightly faster, generally one breath every 3 to 5 seconds, equaling about 12 to 20 breaths per minute. During CPR for these younger age groups, the compression-to-ventilation ratio can be 30 compressions to 2 breaths for a single rescuer. If two rescuers are present, the ratio shifts to 15 compressions to 2 breaths, which can be more effective for maintaining consistent ventilation. Deliver each breath slowly over one second, observing for visible chest rise to avoid forcing air into the stomach.
Recognizing Effective Ventilation
Observing specific indicators helps determine if bag mask ventilation is successful in delivering air to the lungs. The most direct visual cue of effective ventilation is a noticeable rise and fall of the chest with each delivered breath. This indicates that air is entering the lungs and causing them to expand appropriately.
Another sign of effective ventilation is the absence of gastric inflation, which is the distension or swelling of the stomach. Air entering the stomach instead of the lungs suggests that the airway may not be properly open or the seal around the mask is inadequate. A good seal between the mask and the patient’s face is essential, preventing air leakage and directing the delivered breath into the respiratory system. Poor technique, such as overly forceful or rapid breaths, can also contribute to gastric inflation, reducing the effectiveness of lung ventilation.
When Professional Help is Needed
Bag mask ventilation serves as an immediate, temporary measure to support breathing in an emergency. It is not a substitute for comprehensive medical care. Therefore, activating emergency medical services, such as calling 911 or the local emergency number, must be the very first step whenever bag mask ventilation becomes necessary.
Continuing BVM until trained medical professionals arrive is important, as they possess the equipment and expertise to provide advanced life support. Engaging in proper training from certified organizations in CPR and BVM techniques is strongly advised. Such training equips individuals with the necessary practical skills and confidence to perform this life-sustaining intervention effectively in a crisis.