What is BVM: Bag valve mask (BVM) is a hand-held device that can provide manual ventilation to a patient who is not breathing or breathing inadequately. It is also known as an Ambu bag or mechanical ventilator. The BVM has a bag the rescuer squeezes to deliver oxygen to the patient. A one-way valve between the bag and the patient allows oxygen to flow into the patient's lungs but prevents exhaled air from entering the bag. The BVM also has a mask that covers the patient's mouth and nose to deliver the oxygen.
When to use a BVM: A BVM should be used when a patient is not breathing or is not breathing adequately. The BVM can provide positive pressure ventilation (PPV) to a patient who is not breathing or breathing inadequately. PPV is a type of mechanical ventilation in which the patient's lungs are inflated with oxygen-enriched air using a hand-held device, such as a BVM.
How to use a BVM: To use manual ventilation like BVM, ,the rescuer squeezes the bag to deliver oxygen-enriched air to the patient. The one-way valve between the bag and the patient allows oxygen to flow into the patient's lungs but prevents exhaled air from entering the bag. The mask covers the patient's mouth and nose to deliver the oxygen.
When a patient has a respiratory failure or difficulty breathing, the Bag Valve Mask or Pulmonary Manual Resuscitator enables rescuers operating within almost any environment or situation to deliver lifesaving oxygen to the patient's lungs.
Bag mask ventilation is a manual resuscitator or ventilation technique that allows patients oxygenation until a more definitive airway can be established. It is also used in cases where an oropharyngeal airway, endotracheal tube, or other definitive airway control is impossible.
You can use bag-mask ventilation in the field, ambulance, helicopter, the emergency department, the intensive care unit, and the operating room. This may be the only type of ventilator that can work during disasters because they do not require electricity. However, if you use it incorrectly, manual ventilation using BVM can result in serious death or injury. Excessive ventilation may also lead to gastric insufflation and pulmonary aspiration.
The BVM resuscitator is available in a full range of sizes:
BVM is a manual resuscitator that consists of a self-inflating bag, oneway valve, mask, and an oxygen reservoir. There are no parts made from metal, no screws, no washers, springs, or anything else of a complicated nature. The main components are:
BVM is mainly used in prehospital settings to ventilate patients in respiratory failure/respiratory distress and cardiac arrest. Manual ventilation has to be performed by healthcare workers with professional experience who are regularly trained in various medical emergencies like respiratory arrest. It's easier and more effective if two responders are doing the ventilation. The techniques described in this article should be practiced to guarantee successful resuscitation.
For the emergency medical services team, a manual resuscitator using bag-mask ventilation is the only option for airway management. In addition, it is the best option for prehospital airway support in the pediatric population. BVM ventilation is also appropriate for elective ventilation in the operating room when intubation is not required, but it is now often replaced in this setting by the laryngeal mask airway.
BVM ventilation is indicated in the following conditions:
The BVM can be checked by:
You can determine the effectiveness of BVM ventilation by watching if the patient's chest will rise and fall and feeling the resistance of the patient's lungs as they expand. If the ventilation is effective, you will also hear and feel the air escape as the patient exhales.
If the patient is a cardiac arrest victim, your breaths do not need to be synchronized to chest compressions. But ensure that you provide the right number of breaths per minute for the patient's age.
For rescue breathing in adults:
For rescue breathing in pediatrics:
For cardiac arrest, follow established ratios of:
Place the patient in a proper sniffing posture to ensure an excellent nasal breathing pattern. This position aligns the external auditory canal with the sternum. You may need folded towels to achieve the sniffing position. For obese, you may need a commercial ramp device to elevate their shoulders and neck sufficiently. If there is a concern for cervical spine injury:
Sizing of face mask: Face mask sizing is performed by first checking that the mask covers the bridge of the nose and then correctly seats on the chin, ensuring that the lower lip is inside the mask.
To maintain a tight seal, you must perform a C & E hold: With the mask on the patient's face, place your middle, ring and little fingers on the jawbone (forming E) and pull upwards. Concurrently, position your thumb on the bridge of the nose and your index finger below the mask connection and on the chin to make a seal.
Manual ventilation using a bag mask can be done with one person or two, but two-person BVM ventilation is easier and more effective. Your goal is to achieve a tight seal, which usually requires two hands on the mask.
If there are two responders, the experienced emergency medical personnel will handle the mask because maintaining a proper mask seal is the most challenging task. Then, the second responder will squeeze the bag. Remember that excessive ventilation may lead to gastric insufflation and pulmonary aspiration.
Rapid provision of successful spontaneous ventilation and oxygenation is the goal when using a bag valve mask. Successful Bag Valve Mask ventilation requires technical competence and depends on these four things:
Establishing a patent airway for manual ventilation requires keeping the oropharynx clear of physical obstructions, proper positioning and manual maneuvers to relieve tongue and soft tissue obstruction of the upper airway, and airway adjuncts such as a nasopharyngeal or oropharyngeal airway to facilitate effective air exchange.
It's essential to continue bag-valve-mask ventilation until either a definitive artificial airway is achieved or spontaneous ventilation is adequate. If a gag reflex returns while you're doing BVM ventilation with an oropharyngeal airway, remove the oropharyngeal airway and provide continued treatment. A nasopharyngeal airway may be reasonably accepted.
If endotracheal intubation is required, ventilate using maximum FiO2 through a non-rebreather mask for 3 to 5 minutes before inserting the tube. If this is not possible because endotracheal intubation must proceed immediately, pre-oxygenate the patient by giving 5 to 8 vital capacity breaths using a PEEP valve.
Bag mask ventilation should be contraindicated in case of paralysis and induction (because of the increased risk of aspiration). It's also contraindicated if the upper airway or passage by which air reaches the lungs is completely blocked.
The complications of BVM Ventilation include barotrauma from too much lung inflation and gastric insufflation, leading to vomiting and aspiration. In addition, if bag-valve-mask ventilation is used for a prolonged period or improperly performed, air may be introduced into the stomach.
Untrained individuals cannot use bag valve masks in response to an overdose event. Spontaneous ventilation is crucial to responding to an opioid overdose to restore breathing, get oxygen into the blood, and keep the brain alive. If you are not trained in using BVM, give breaths, call 911 and give naloxone instead of initiating BVM.
Although Bag Valve Masks are appropriate for trained first responders, effective and adequate ventilation of BVM is an advanced skill that requires training and hands-on practice. You will not be able to use them correctly if you have not been trained. The following are the potential harms if BVM ventilation was performed incorrectly:
Is a bag valve mask considered mechanical ventilation?
No. Mechanical ventilation refers to using a specialized machine called a ventilator, while a bag valve mask falls under manual ventilation.
Can anyone perform a bag valve mask ventilation?
Bag Valve Mask requires training and practice to use it effectively. Even emergency medical responders with much practice find it difficult to maintain adequate mask seals and ventilate sufficient volumes when only one responder can use it.
Are bag valve masks reusable?
Bag Valve Mask can either be reusable or disposable.
Do oxygen masks expire?
Most disposable respirators have an expiry date; once this date has passed, you should not use the bag-mask ventilation.
What is the correct volume of air during BVM?
A normal adult BVM holds about 1.5 L of air, almost three times the American Heart Association's recommended 600 mL tidal volume for an adult patient.
What is the preferred technique for BVM ventilation?
Two-person bag-mask ventilation technique is preferred because two trained and experienced rescuers will perform it. Rescuer 1 opens the airway and seals the mask to the face while rescuer 2 squeezes the bag. Both rescuers watch for visible chest rise.
Do you connect the bag valve mask to oxygen?
You can use a bag valve mask even though it's not connected to an oxygen tank. You can use it to provide room air or 21% oxygen to the patient.