Figure 1. An Example of How a Heart-Lung Machine Works (Source)
We all often hear about the common term of "open-heart surgery" used by most people as a joke related to the medical profession, but what most of us do not really know is that it actually is an extremely difficult procedure. The key device in that facilitates this is the heart-lung machine. Its function is to take deoxygenated blood from the body to bypass the lungs and heart The key components that control a heart-lung machine are the tubing, one of 2 types of pumps ( Roller and Centrifugal), the oxygenator, and cannulae. The oxygenator is responsible for substituting the role of the lungs to resupply the blood with fresh oxygen for the body. Cannulae are usually sewn into multiple locations on the patient depending on the surgery. They remove oxygen depleted venous blood from the body and feed it to the system.
In 1885, Austrian-German physiologist Maximilian von Frey constructed an early prototype of a heart-lung machine at the University of Leipzig. However, the concept was not feasible because blood would start to clot outside the body until 1916 when heparin was discovered. In 1931 John Gibbon was moved by the death of a patient during cardiac surgery and was convinced that patient could have survived if blood circulation was artificially maintained. Like many medical advances, the heart-lung machine depended heavily on animal research. Initially, the machine accomplished its job in a cat in 1935, but it damaged the blood cells too much so the cat eventually died. The primary problems that needed to be addressed were the prevention of air from entering the system and clot prevention. It wasn't until 1945 following tests on dogs that the machine was deemed ready for human patients. A breakthrough occured in 1953 when Gibbon eventually performed his first successful operation on Cecelia Bavolek. Even though the results were a success, there was still one major flaw, the heart would continue beating during the operation. This problem was eventually solved later with a combination of chemicals and temperature regulation
Sources: History, Concept, General
In 1885, Austrian-German physiologist Maximilian von Frey constructed an early prototype of a heart-lung machine at the University of Leipzig. However, the concept was not feasible because blood would start to clot outside the body until 1916 when heparin was discovered. In 1931 John Gibbon was moved by the death of a patient during cardiac surgery and was convinced that patient could have survived if blood circulation was artificially maintained. Like many medical advances, the heart-lung machine depended heavily on animal research. Initially, the machine accomplished its job in a cat in 1935, but it damaged the blood cells too much so the cat eventually died. The primary problems that needed to be addressed were the prevention of air from entering the system and clot prevention. It wasn't until 1945 following tests on dogs that the machine was deemed ready for human patients. A breakthrough occured in 1953 when Gibbon eventually performed his first successful operation on Cecelia Bavolek. Even though the results were a success, there was still one major flaw, the heart would continue beating during the operation. This problem was eventually solved later with a combination of chemicals and temperature regulation
Sources: History, Concept, General
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