What types of pumps are used in heart-lung machines?

Heart-lung machines, also known as cardiopulmonary bypass (CPB) machines, employ specific types of pumps to fulfil their function during cardiothoracic surgeries. These pumps provide the necessary circulation and oxygenation of the patient's blood while their heart and lungs are temporarily bypassed. Two main types of pumps are commonly used in heart-lung machines:

1. Centrifugal Pumps:

- Centrifugal pumps are widely used in heart-lung machines due to their high flow rates and ability to handle varying pressures.

- They consist of a spinning impeller that rotates within a housing, creating a centrifugal force that propels the blood outward.

- These pumps provide continuous blood flow and are suitable for longer procedures.

2. Roller Pumps:

- Roller pumps, also known as occlusive pumps, employ a set of rotating rollers that compress a flexible tubing or a series of rollers against a rigid track.

- As the rollers move, they compress the tubing, propelling the blood forward.

- Roller pumps provide precise control over blood flow and are preferred when pulsatile flow is desired, mimicking the natural contractions of the heart.

Both centrifugal and roller pumps play crucial roles in heart-lung machines. They are carefully designed to minimize damage to blood cells and ensure adequate circulation during complex surgical procedures. The choice of pump type depends on various factors, including patient characteristics, surgical requirements, and the surgeon's preferences.