By: Kaylie Dalton
The field of medicine has been rapidly advancing for the last few centuries and even more so the last few decades. We have come a long way from the four humors and “bloodletting”. Today robots are being used in surgeries and new machines for various medicinal uses are appearing yearly. Despite all of our acquired knowledge and new technologies there are still situations that arise that result in either death or severe damage to a patient regardless of our best efforts to save them. One such situation occurs when a patient has decreased lung functionality due to one reason or the other, be it disease or drowning. These cases quickly become emergencies that traditional methods of oxygen administration are not effective in correcting. It is from situations like these that the idea of intravenous oxygen delivery was created.
One of the very first things health care providers are trained to assess are patient airways. Is the patient breathing? Is that breathing adequate and stable? What are their oxygen saturation levels, or in other words, is the oxygen they are breathing actually making it through the lungs and into the blood stream? A “No” to any one of these questions results in some sort of medical intervention and the administration of oxygen through various methods and techniques. This is because the level of oxygen within a patient’s blood stream plays a critical role in the overall health and survival of the patient. As everyone knows, a patient must be breathing and therefore have oxygen in their bloodstream in order to survive. Going for even a few minutes without adequate oxygen saturation levels results in widespread organ damage, starting with the brain, and death (Medline Plus).
Currently oxygen can only be delivered though inhalation and mechanical ventilation using a variety of equipment with varying effectiveness. Oxygen is most commonly inhaled through either a non-rebreather mask or NRB, or a Nasal Cannula. Each of these devices require different flow rates, for example a NRB typically is connected to oxygen gas that is flowing at a rate of about 15 liters per minute and a Nasal Cannula has oxygen gas flowing through it at around 4 liters per minute. Each device fits on the patient’s face either over their mouth or in their nose and provides concentrated levels of oxygen gas for a patient in need to inhale. The idea is that the oxygen gas will be breathed in by the patient, enter the lungs, and from there transfuse to the patient’s blood stream where it can travel throughout the body to where it is needed. These methods have been effective and even lifesaving in certain situations however, they are only as effective as the patients lungs are functional.
Conditions that render oxygen inhalation less effective are conditions in which the patient’s lung function is diminished. For instance patients with COPD and other forms of lung disease will have a decreased ability to absorb oxygen into their blood. Patient’s also suffering from conditions such a pulmonary edema where fluid is actually disrupting oxygen transfusion also do not benefit fully from inhaled oxygen. Another flaw in the current method of oxygen delivery is that the patient’s blood must be circulating in order for it to be effective. If the patient’s blood is not circulating, the oxygen will make it from the mask into the patient’s lungs and then into the blood, however, it will not have the means to move throughout the body. In order to provide a higher standard of care and to ensure the health of patients in a variety of conditions a more effective and direct way of oxygen delivery is necessary. It is from such obstacles that the idea of intravenous oxygen delivery was born.
In 2006 Dr. Kheir of Children’s Medical Hospital was attending to a young girl suffering from a severe case of pneumonia. As the night progressed, the girl’s condition became more and more critical until her lungs were so full of fluid she was unable to breathe and therefore suffered respiratory arrest. Dr. Kheir and his team put forth every action and treatment possible to save the girl, but in the end she perished as a result of the severe damage her low oxygen levels inflicted on her brain. The team had done everything right and everything within their power to save the girl using current technology and techniques but in the end could still not save her for two reasons. The first is that her oxygen levels in her blood were too low and as a result caused widespread organ damage and the second is that they simply ran out of time before she could be hooked up to a heart-lung machine (Boston Children’s Hospital). The tragic situation motivated Dr. Kheir and his team to begin researching a method that would provide a solution to both of these problems.
Realizing that maintaining the young girl’s oxygen saturation levels would have undoubtedly saved her life, Dr. Kheir set out researching another form of oxygen delivery. A form that would be effective even when a patient’s lungs were rendered ineffective. His possible solution was published Science Translational Medicine in June of 2012 and came in the form of oxygen gas filled microparticles within a foam suspension that could then be injected intravenously into a patient’s blood stream.
The initial experiments were relatively simple with hit and miss results. First the researchers would draw blood and then mix it with a solution of oxygen gas filled microparticles. If it was successful, the blue unoxygenated blood would turn bright red with oxygenation. To simulate real life situations, the team used rabbit's whose tracheas where completely occluded and injected the microparticle solution directly into the rabbit's blood streams. For up to 15 minutes the rabbits survived without taking a single breathe (Kheir). They also had lower rates of severe organ damage compared to the control rabbits that were injected with a saline solution (Kheir). In a critical care patient, 15 minutes of extra time means the difference between life and death. If a patient’s oxygen saturations levels are being maintained by the injected oxygen solution, health care providers could have more time to begin longer lasting methods to stabilize the patient such as connecting the patient to a heart-lung machine, placing a chest tube, and performing emergency surgeries.
The idea itself seems relatively simple. If one can inject a multitude of other medications through an IV why should oxygen be any different? The major obstacle in creating oxygen that can simply be injected into a patient’s blood involves the form or state of the oxygen that is being injected. If one were to basically inject air into the blood stream the result would be far from a more oxygenated patient. In fact, the patient would most likely be dead within seconds and if not dead, then in a condition close to it. How is it then that intravenous oxygen delivery is even possible? In order to overcome the potential damage of injecting a gas into the bloodstream, Dr. Kheir and his team had to create the solution so that the oxygen gas would not form an embolus in the patient’s blood stream which could then potentially occlude veins and wreak havoc throughout the body. The solution created to avoid this issue consists of microscopic particles that are made up of lipids which are found naturally in the body and filled with oxygen gas. This enables the particles to dissolve in the blood in such a way that the oxygen will attach to hemoglobin molecules and will not create pockets of air within the blood stream. Another factor that partially contributes to the solution’s effectiveness is that there is a high amount of oxygen contained within a small volume making the solution immensely dense (Boston Children’s Hospital). This means only small amounts will have to be injected in order to restore the needed saturation levels of oxygen within a patient’s blood stream.
The idea of injecting lifesaving oxygen intravenously is on its way to becoming a feasible treatment that could be used in all fields, especially emergency medicine. However, as with every great idea, there are some hurdles that must first be overcome before it can serve as a safe reliable treatment. Currently the problems that need additional studies include the removal of carbon dioxide in the blood stream that forms almost simultaneously with oxygenation and the long term possible effects the foam solution may have within the body (J. N. Kheir). The possible result of further studies on the subject will be that one day ambulances and hospitals will be stocked with this potentially lifesaving treatment.
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