Bag-Valve-Mask Ventilation - Indications, Contraindications, Procedure, and Complications

Introduction:

Bag-valve-mask (BVM) ventilation is used to treat patients with inadequate breathing. These patients usually require emergency management and are admitted to the intensive care unit. It is useful for patients who can breathe on their own but requires additional oxygen flow. It is composed of four parts, namely a facemask, a reservoir bag, two to three valves, and a flexible tube attached to the oxygen tank. One-way valves are commonly preferred for BVM ventilation. The one-way valve prevents the entry of expired air into the reservoir bag. It also removes the air outside the mask. It prevents the inhalation of air from the atmosphere.

What Are the Indications of BVM Ventilation?

BVM ventilation is used to manage the following medical conditions:

• Apnea - BVM ventilators can be used in patients with mild to moderate apnea.

• Mental Disturbances - Patients with altered mental status are unable to prevent airway obstruction. Such patients are managed by BVM ventilation.

• Surgery - BVM ventilation is used in patients who are undergoing major surgery with anesthesia.

• Respiratory Failure - BVM ventilation is used to support breathing mechanisms in patients with respiratory failure, decreased oxygen flow, and increased carbon dioxide.

• Traumatic Injuries - Road traffic traumas may cause injury to the chest and lungs and interfere with breathing. BVM ventilators are used to manage this condition.

• Fume Inhalation - Inhalation of poisonous gasses like carbon monoxide and nitrous oxide causes potential damage to the lungs. This is overcome by using BVM ventilation.

• Severe Headaches - Patients with cluster headaches require a high oxygen flow, so it is supplied using BVM ventilation.

What Are the Contraindications of BVM Ventilation?

BVM ventilation has limited use in certain conditions. They are as follows:

• Increased Facial Hair - BVM ventilators are difficult to use in patients with excess beard growth.

• Absence of Teeth - It is hard to ventilate the edentulous patients (toothless) with BVM ventilators.

• Elders - The elderly patients are unable to tolerate the BVM ventilators placed over them.

• Snoring - BVM ventilators cannot be used in patients with severe central sleep apnea. It is also contraindicated in snoring individuals.

• Obesity - The obese individual has an increased narrowing of the airway, so BVM ventilation is contraindicated.

• Restricted Jaw Growth - Patients with limited mouth opening due to stiff facial muscles and underdeveloped jaw are difficult to manage using BVM ventilators.

• Denture Patients - There is a high risk of obstruction in patients using dentures. However, a skillful healthcare provider can manage BVM ventilation without interruption.

• Paralysis - It cannot be used in patients who recently had paralysis because there is an increased risk of aspiration.

• Airway Obstruction - BVM ventilation cannot be used in patients with total airway obstruction due to cellulitis or a large tongue.

What Are the Complications of BVM Ventilation?

There are a few complications associated with BVM ventilation. They are as follows;

• Barotrauma - Artificial ventilation can rupture the air sacs and causes lung expansion. This condition is called barotrauma.

• Bloating - The excess pressure elicited due to prolonged BVM ventilation results in bloating.

• Vomiting - The accumulation of air due to continuous BVM ventilation induces nausea and vomiting. Some patients also have blood streaks in their vomit.

• Aspiration - The foreign object aspiration may enter the respiratory tract and obstruct the windpipe during BVM ventilation.

How to Prepare for BVM Ventilation?

• The patient should lie in a supine position before the procedure.

• The head must be extended from the neck. It is heightened by placing extra towels or pillows under the patient's head.

• Do not move the neck or head to avoid dislodgement.

• Inform the medical provider if the patient has experienced any gag reflex in previous surgeries.

• The oropharyngeal airway is used in patients with a gag reflex.

• The patient should choose the right-sized mask before the BVM ventilation procedure. It should cover the nose and mouth.

• The vital signs like end-tidal carbon dioxide level, oxygen saturation, and breath sounds are continuously monitored to prevent suffocation.

What Is the Procedure for BVM Ventilation?

• Two operators are required for effective BVM ventilation. One operator maintains the seal with the mask. The other operator handles the bag.

• The nasal bridge is covered with the nasal portion of the mask. The operator should cover the nasal folds and lower lip for a tight seal.

• The operator should not apply pressure over the eyes, chin, and neck. Avoid pressure in the soft tissue areas as it leads to obstruction of the airway. So apply pressure on the hard tissues like the lower jaw.

• Then the bag is attached to the mask and squeezed for ventilation.

• The tidal volume of 500 milliliters (six to seven milliliters per kilogram) over one second is achieved by inflating the bag. For a 1000 milliliters (mL) bag, the halfway squeeze is enough. This is the normal range for average-sized adults. It varies depending on the medical condition.

• The operator should squeeze the bag gently with constant pressure. This process should occur simultaneously with each breath. This process is known as bag ventilation.

• Patients who had a cardiac arrest in recent days should be delivered within eight to ten breaths per minute.

• The operator should observe the changes in the chest level. The increase in tidal volume may raise the chest level.

• The forced air pressure enters the lungs and helps in the respiratory mechanism.

What Are the Risk Factors Associated With the Use of BVM Ventilators?

The two major risks of manual BVM ventilators include the following;

• There is an increased prevalence among the public leading to a high risk of exposure.

• Manual use by the patient without the help of a healthcare professional can result in uncontrolled hyperinflation of the lungs.

Conclusion:

BVM ventilators are considered the first-line device for the management of critical patients in the emergency room. It is also utilized as an artificial ventilator for rescue by firefighters and paramedics during fire accidents and road traffic accidents, respectively. Handling techniques and guidelines for using BVM ventilators must be carefully studied before using them to avoid hyperventilation. Caretakers should monitor the pediatric self-inflating bag periodically. The port attached to the device should be monitored continuously for positive-pressure ventilation.