Biphasic cuirass ventilation

Biphasic cuirass ventilation (BCV), also known as chest cuirass ventilation or shell ventilation, is a form of mechanical ventilation that provides ventilatory support to patients with respiratory failure. This method of ventilation is unique in that it utilizes a cuirass, a shell-like device that covers the chest and/or abdomen, to create a negative pressure environment that facilitates breathing.

History

The concept of BCV has its roots in the iron lung, a negative pressure ventilator used extensively in the mid-20th century during the polio epidemic. The iron lung encased the entire body, excluding the head, and alternated between negative and positive pressure to simulate breathing. BCV evolved from this concept, focusing the negative pressure on the chest and/or abdomen to stimulate the diaphragm and intercostal muscles.

Mechanism

BCV works by alternately applying negative and positive pressure to the chest and/or abdomen. The cuirass, a rigid shell-like device, is sealed around the patient's chest or abdomen. A ventilator then alternates between creating a negative pressure within the cuirass, causing the patient's chest to expand and air to be drawn into the lungs, and a positive pressure, causing the chest to contract and air to be expelled from the lungs.

Applications

BCV is used in both acute and chronic settings. In the acute setting, it can be used for patients with respiratory failure due to conditions such as pneumonia, acute respiratory distress syndrome (ARDS), and COPD. In the chronic setting, BCV can be used for patients with neuromuscular diseases, such as amyotrophic lateral sclerosis (ALS) and Duchenne muscular dystrophy, who have difficulty breathing on their own.

Advantages and Disadvantages

BCV has several advantages over other forms of mechanical ventilation. It is non-invasive, reducing the risk of infection and other complications associated with invasive ventilation. It also allows for the patient to talk, eat, and drink while receiving ventilatory support. However, BCV also has its disadvantages. It requires a good seal between the cuirass and the patient's body, which can be difficult to achieve in certain patients. It also may not provide adequate ventilation in patients with severe respiratory failure.

See Also

• Mechanical ventilation
• Respiratory failure
• Iron lung