Medical technology: Guinness world record for the smallest heart-lung machine

The small miracle machine enables heart operations in infants without preserved blood

Cardiotechnician Wolfgang Böttcher from the German Heart Center Berlin (DHZB) has received the official world record certificate from the "Guinness World of Records" company for the heart-lung machine with the world's smallest filling volume. Even if some people can not do anything with this record, decades of development work are behind the project. The little helper enables complicated heart operations on newborns without the need for foreign blood, which has considerable advantages for the babies.

The German Heart Center Berlin reports that complex congenital heart defects often have to be operated on very soon after birth. The heart is connected to a heart-lung machine for this operation. This must be filled with a suitable liquid beforehand so that no air is pumped into the body. In the past, donor blood was often used as a liquid, which, despite the most careful examination, held a certain risk potential for infections and intolerance reactions. Today, the heart-lung machine is mostly filled with a sterile electrolyte solution.

What is the big advantage of the small filling volume?

The electrolytic solution causes the blood to thin temporarily. In adult patients, this does not pose any danger. In newborns or small children, however, such dilution can have far more drastic consequences, since only around 85 milliliters of blood per kilogram of body weight circulate in the newborn. For this reason, foreign blood preserves had to be used in such operations. The filling volume of the new heart-lung machine of the German Heart Center Berlin is so small, however, that even babies can be operated on with an electrolyte solution without the blood being excessively diluted. This enables interventions without foreign blood.

The development of the little miracle machine

A problem with the development was that the most important components of the machine, the pump and the oxygenator, could not be reduced further. "However, the largest part of the filling volume of a heart-lung machine does not claim its individual components at all, but the tubes that connect the components and that lead from the heart-lung machine to the patient," explains DHZB cardiotechnician Wolfgang Böttcher. Thus, the developers concentrated on keeping the hose connections as short as possible. The solution was to place the individual components of the machine as close together as possible and to place the machine as close as possible to the operating table without the operator having to restrict his work. "At first this may seem relatively simple, but the details are a challenge," reports Böttcher in a report by the DHZB. The life of a child ultimately depends on the reliable functioning of the heart-lung machine. Every change to this system had to be carefully planned and implemented.

The years of work pay off

With a filling volume of 73 milliliters, the heart-lung machine received the world record. The DHZB is now the only heart center in the world where interventions can be carried out on newborns and premature babies without preserved blood, even on premature infants weighing less than 2000 grams. "Not only can we minimize the risk of infection and intolerance, we can also often enable our patients to recover more quickly after the operation," says Prof. Joachim Photiadis, head of the Clinic for Pediatric Cardiac Surgery at the DHZB. According to Photiadis, it has been proven that the ventilation time required after the operation, and therefore usually the patient's stay in the intensive care unit if no foreign blood is used, is shorter on average. In addition, a heart-lung machine that does not need to be filled with donor blood can be used again more quickly and is available to the next patient faster. (fp)

Author and source information

Video: How heart-lung machines can harm the kidneys during cardiac surgery (January 2022).