Boston Children’s Hospital Researchers Able To Bypass The Lungs By Using Injectable Oxygen
Researchers from the Boston Children’s Hospital managed to sustain life in rabbits with blocked tracheae through the use of oxygen-filled microparticles. They injected the particles into the blood stream of the rabbits and managed to keep them alive for almost 15 minutes without a real breath of air. Researchers say that if the novel method would be used in the emergency room, it would save countless more lives. The research team provides a new way to deliver oxygen to the bloodstream and tissues, by bypassing the lungs through the use of injectable oxygen.
Patients who are unable to breathe through their lungs, due to either lung failure or a type of obstruction, need an alternative way of getting oxygen into their bloodstream. Lack of oxygen can lead to brain injury and cardiac arrest. The research team says their new technique can delay the onset of brain injury, cardiac arrest or other tissue injuries that could be induced due to lack of oxygen.
Most of the previous techniques that were attempted in order to treat hypoxemia (an abnormally low concentration of oxygen in the blood) and cyanosis (a bluish discoloration of the skin caused by lack of oxygen in tissues) have had different success rates. Many of the previous techniques used free oxygen gas injections directly into the bloodstream. This is dangerous because the oxygen bubbles can aggregate and form gas bubbles that lead to pulmonary embolism, a lethal blockage.
The current study was published in the journal Science Translational Medicine, reporting a new method that removes the danger of injecting free oxygen gas into the bloodstream.
The lead author of the study, Dr. John Kheir, from the Cardiology department of the Boston Children’s Hospital, and his team of researchers have designed a new microparticle that consists of a small pocket of oxygen gas surrounded by a single layer of lipids. The team explains that pulmonary embolisms are averted because after the injection in the bloodstream, each gaseous oxygen particle is prevented from aggregating with the other particles, thus no large oxygen bubbles are formed.
According to the journal Nature, Dr. Kheir reports that once in the bloodstream, the oxygen particles mix with circulating red blood cells and the oxygen diffuses into these cells almost immediately after contact. The research team notes that their new microparticle technique is unlike any other type of artificial blood because it does not require oxygen to brought from the lungs. Dr. Kheir also added that after the oxygen dissociates from the fatty molecule, the molecule break off and can be easily reabsorbed by the organism.
The research team injected this new solution in rabbits and discovered that the test animals survived almost 15 minutes without any breaths of air. The blood pressure and heart rate of the animals was also tested and found to be normal. Furthermore, test conducted showed no heart, lung or liver damage, which are signs currently associated with oxygen deprivation. These symptoms can also be caused by the injection of free oxygen into the bloodstream.
“Essentially as soon as we started injecting it, clinically we started to see an effect” said Dr. Kheir. However, Dr. Kheir notes that the oxygen levels drop as quickly as they rise, after the injection is stopped, thus meaning that the microparticles must be continuously injected in order to obtain a prolonged effect.
The research team notes that this new microparticle solution is portable, and more importantly, cheap to make, therefore it can be used in emergency situations to stabilize the patient, thus allowing doctors to perform other urgent therapies.
“This is a short-term oxygen substitute—a way to safely inject oxygen gas to support patients during a critical few minutes. Eventually, this could be stored in syringes on every code cart in a hospital, ambulance or transport helicopter to help stabilize patients who are having difficulty breathing”, said the lead author of the study.
A drawback of the technique is that these microparticles can only be administered for a maximum of 30 minutes. This is due to the fact that the microparticles are injected along with a liquid solution. Administering fluids for longer periods of time would overload the bloodstream.
According to the journal Science, Dr. Kheir said that if the team manages to increase the ration of microparticles to fluid, it would allow doctors to inject the solution for a longer period of time.
Dr. Peter Laussen from the Boston Children’s Hospital says that this potential breakthrough can have many uses across the field of medicine, from emergency rooms and intensive care units, to operating rooms and battlefields.