New system uses xenon to protect brain in critically ill infants

Washington, July 26 (ANI): A newly developed system, called "closed circuit system", has the potential to make xenon gas feasible, safe, and cost efficient for use in protecting the brains of critically ill infants, according to a study.

Researchers led by Dr. John Dingley of the University of Wales, Swansea, have introduced a new method of giving xenon to newborn infants with birth defects and other life-threatening conditions requiring surgery and anaesthesia.

The usual reason for newborns to undergo surgery is a critical problem with the infants' breathing or circulation that prevents their tissues from getting enough oxygen, which damages the brain, with long-term consequences for the child.

It is known that xenon provides protection against some forms of low-oxygen injury to the brain, but because of it is extremely expensive, its use is currently limited to a few experimental centres.

Thus, the researchers have designed a closed-circuit xenon delivery system that takes advantage of the fact that uptake of xenon by the lung is very low-when a given amount of xenon is breathed in, almost all of it is breathed out.

The new system, fitted to a conventional newborn ventilator, essentially recaptures the exhaled xenon so that the infant can re-breathe it.

The system adds precise amounts of oxygen and other gases as needed.

The researchers tested their closed-circuit xenon delivery system on newborn pigs, and found that they could precisely control the depth of anaesthesia, while delivering exactly the right amount of oxygen.

The piglets had stable vital signs, and recovered without any complications.

The xenon system could be used with our without cooling of body temperature (hypothermia).

The researchers have estimated that by using the closed circuit system, xenon could be used for surgery in critically ill newborns for as little as 2 dollars per hour.

This would allow "responsible use of a restricted global xenon supply in the maximum number of clinical cases per year," said the researchers.

They believe that the simple design and operational cost of the system should make the delivery of xenon-once considered prohibitively expensive for routine medical use-safe and inexpensive for newborns requiring surgery and anaesthesia for life-threatening birth defects.

The study appears in the August issue of Anesthesia and Analgesia, official journal of the International Anesthesia Research Society (IARS). (ANI)