Ambu bag (bag valve mask) – How to use & is it an alternative to a ventilator?

What are Ambu Bags?

An AMBU bag, also known as a manual resuscitator or bag valve mask (BVM), is essential for providing respiratory support in both emergency and non-emergency scenarios. It comprises a self-inflating bag, a mask or mouthpiece, and a valve for air control. Originally named as an abbreviation for "artificial manual breathing unit," the device was first created by Testa Laboratory and later became synonymous with the term "Ambu bag" after the company rebranded as Ambu in the 1980s. This device is crucial for delivering controlled airflow to patients requiring assistance with breathing.

How does an Ambu Bag Work?

The AMBU bag operates with manual squeezing to administer breaths to patients via a mask or mouthpiece. Its valve enables precise control over airflow and pressure levels. This device is versatile, suitable for patients across all age groups, from newborns to adults, ensuring effective respiratory support in various medical settings.

8 Key Uses of Ambu Bags:

Resuscitation - Ambu bags provide immediate respiratory support during cardiac arrest or respiratory failure by delivering manual ventilation to ensure oxygenation and carbon dioxide removal. They are often used in emergency settings by first responders and medical professionals.

Ventilation During Intubation - Ambu bags assist in maintaining patient oxygenation while securing an airway, helping to prevent hypoxia during the intubation process. They are used as a temporary measure until mechanical ventilation can be established.

Temporary Ventilation - Ambu bags offer short-term respiratory support during patient transport or procedures where mechanical ventilation is not immediately available. They ensure continuous oxygen delivery and ventilation in various clinical scenarios.

Weaning from Mechanical Ventilation - Ambu bags aid in gradually reducing ventilatory support, providing manual ventilation to assess a patient's ability to breathe independently. They are used in step-down care to facilitate the transition from mechanical ventilation to spontaneous breathing.

Respiratory Distress - Ambu bags deliver immediate respiratory assistance to patients experiencing acute respiratory distress, helping to stabilize breathing and oxygenation levels. They are crucial in emergency situations, including severe asthma attacks or COPD exacerbations.

Pre-hospital Care - Ambu bags are essential tools for first responders and paramedics, providing life-saving ventilation before hospital arrival. They are portable and easy to use in various pre-hospital environments.

Neonatal Resuscitation - In neonatal resuscitation, Ambu bags are critical for providing ventilation to newborns experiencing respiratory distress or failure at birth. They ensure effective oxygenation and ventilation in neonatal intensive care units (NICUs) and during resuscitation procedures following birth complications.

Training and Simulation - Ambu bags are utilized in medical training to practice manual ventilation techniques, enhancing preparedness for emergency scenarios among healthcare professionals. They support realistic simulation exercises in medical education programs.

How to use an Ambu Bag?

To use an Ambu bag on a patient, follow these steps:

• Assemble the Ambu bag and ensure it is properly disinfected.
• Attach the bag to the patient’s mouth using the appropriate mask.
• Adjust the valve to the desired flow rate and pressure.
• Squeeze the bag to deliver breaths to the patient.
• Monitor the patient’s vital signs and adjust the flow rate and pressure as needed.

Adhere to proper infection control protocols to prevent disease spread. Correct use of an Ambu bag is crucial to maintaining airway patency and providing essential respiratory support to a patient.

Advantages of Using an Ambu Bag:

• Ambu bags can be rapidly deployed to provide emergency respiratory assistance to patients who are not breathing or have stopped breathing.
• Lightweight and portable, Ambu bags require no electricity, making them ideal for emergency use in remote or rural areas.
• These devices provide respiratory support without the need for invasive procedures such as intubation.
• Compared to other forms of respiratory support, Ambu bags are relatively inexpensive, making them an accessible and economical option for emergency medical care.
• Ambu bags can be used to provide respiratory support to patients of all ages, from infants to adults, and are suitable for various settings, including hospitals, clinics, and ambulance services.

Types of Ambu Bags:

Ambu bag types can be described as below:

Reusable - Reusable Ambu bags are designed for multiple uses. They are typically made of durable materials that can withstand repeated sterilization, making them suitable for long-term use in medical facilities.

Disposable - Disposable Ambu bags are intended for single use. They are designed to be used once and then discarded, reducing the risk of cross-contamination and infection, making them ideal for emergency situations and settings with high patient turnover.

For infants and children up to 10 kg - he Infant Ambu bag is specifically designed for neonatal and infant patients. It is smaller in size with a capacity of 240 ml, ensuring it delivers the appropriate volume for young patients. Equipped with an adjustable pressure-limiting valve, it regulates the pressure during ventilation to prevent over-inflation. Additionally, the Infant Ambu bag features an oxygen reservoir bag to provide high concentrations of oxygen. It comes with various mask sizes specially designed to fit an infant's face.

For pediatric patients weighing 10 to 40 kg - The Pediatric Ambu bag is designed for pediatric patients, with a capacity of around 500 ml to accommodate their smaller size. It features an adjustable pressure-limiting valve to regulate ventilation pressure and prevent over-inflation. Additionally, the bag includes an oxygen reservoir to deliver high concentrations of oxygen. It comes with various mask sizes specifically designed to fit a child's face.

Adult, for people weighing more than 40 kg - The Adult Ambu bag is designed for providing positive pressure ventilation to adult patients experiencing breathing difficulties or respiratory distress. It typically has a capacity of around 1600 ml and features an adjustable pressure-limiting valve to regulate the delivered pressure during ventilation. Additionally, it includes an oxygen reservoir bag for delivering high concentrations of oxygen.

How do you clean an Ambu bag after use?

When reusing a reusable Ambu bag, thorough cleaning is essential to maintain hygiene and prevent infections. This involves disassembling the bag, removing visible contaminants with hand-rinsing, and washing it with a suitable cleaning solution. After rinsing to ensure all debris is removed, some reusable Ambu bags can be sterilized in an autoclave at high temperatures. Alternatively, disinfection with a 2% glutaraldehyde solution for at least 20 minutes is effective for sterilization. If proper cleaning and sterilization equipment aren't available, using disposable Ambu bags is recommended to ensure hygiene standards are met.

Using an Ambu bag requires proper training and skill, as incorrect use can cause harm to the patient. Here are some general guidelines:

• Ensure the patient's airway is clear and open.
• Select the appropriate size Ambu bag for the patient.
• Connect the Ambu bag to an oxygen source, if available.
• Inflate the bag by squeezing it.
• Place the mask over the patient's face, ensuring a tight seal.
• Squeeze the bag to deliver air to the patient.
• Monitor the patient's breathing and adjust the air flow as needed.

Is Ambu Bag a True Alternative to a Ventilator?

An Ambu bag, or bag valve mask (BVM), can provide temporary respiratory support in emergencies but is not a true alternative to a ventilator. While an Ambu bag requires manual operation to deliver breaths and is useful for short-term, immediate interventions, a ventilator offers automated, precise, and continuous respiratory support for patients requiring long-term assistance. Ventilators are more suitable for critically ill patients who need consistent and controlled ventilation, whereas Ambu bags are ideal for short-term use in emergency situations until more advanced care is available.

Recognizing When BVM Ventilation Should Be Avoided: Contraindications and Precautions

Avoiding BVM ventilation, also known as bag valve mask ventilation, is crucial in certain situations due to specific contraindications and precautions:

Facial Trauma: Patients with significant facial injuries, especially those affecting the airway or mask seal, may not benefit from BVM ventilation and could experience worsened trauma or airway compromise.

Inadequate Mask Seal: If a proper seal cannot be achieved over the patient's face due to anatomical reasons or positioning, BVM ventilation may not effectively deliver oxygen or air to the lungs.

Gastric Distension: In patients at risk of or with known gastric distension, such as those with bowel obstructions or recent abdominal surgery, BVM ventilation can exacerbate this condition, potentially leading to vomiting and aspiration.

Uncontrolled Airway Bleeding: Patients with uncontrolled airway bleeding or suspected airway obstruction from foreign bodies may not benefit from BVM ventilation and require specialized interventions to maintain airway patency and prevent further complications.

Inexperienced Users: Inexperienced or inadequately trained users may inadvertently cause harm or fail to effectively ventilate the patient using a BVM, highlighting the importance of proper training and proficiency in its use.