Israeli medical device aims to boost CPR survival rates
The device can squeeze approximately one liter of blood out of the limbs into the heart in less than 30 seconds and completely blocks blood flow back into the legs.
By EYTAN HALONThe HemaShock device made by Oneg HaKarmel is applied during a demonstration (photo credit: Courtesy)
According to a recent study examining 8,000 cases of out-of-hospital cardiac arrest in the United Kingdom, less than 16% arrived at the emergency room with a functioning heart. Just 2.8% of patients were still alive 30 days after the incident, with only two-thirds of those neurologically intact.The reason for widespread resuscitation failure, even when performed by professional health care providers with electric defibrillation and adrenaline at their disposal, is the low blood flow to the coronary arteries and cerebral circulation during standard cardiopulmonary resuscitation (CPR).Seeking to improve patients’ chances of survival following a cardiac arrest or severe blood loss is veteran emergency physician and cardio-pulmonary physiologist Prof. Noam Gavriely, the founder of medical devices company Oneg HaKarmel (OHK).“When a bystander or a medic is doing CPR to try to activate the heart as a pump, their efficacy is only about 25% of the normal,” Gavriely told The Jerusalem Post.“This is not because we’re not compressing hard enough. Rather the problem is that the blood is in the periphery and the heart is empty. With an empty heart, it doesn’t matter how hard you press it, blood will just not come out.”Inspired both by an old anti-g flight suit worn by jet pilots which pushes blood from the legs into the core to ensure the brain continues to receive blood flow and oxygen, and the use of similar technology in the Korean War in the 1950s, Gavriely invented the HemaShock – an elastic silicone torus wrapped by a stockinette quickly applied to the lower limbs promptly after resuscitation commences.The device can squeeze approximately one liter of blood out of the limbs into the heart in less than 30 seconds and completely blocks blood flow back into the legs. By comparison, an intravenous blood transfusion for half that quantity would require 15-30 minutes.“We are channeling blood to the essential organs – to the heart itself, the coronary arteries, the brain, the kidneys, the liver. Those organs are very sensitive to lack of oxygen,” said Gavriely.“The legs can sustain two hours without any blood flow, as we know from orthopedic surgery where tourniquets are routinely used.”In the case of severe shock, the HemaShock is applied to one leg and vital signs are then measured. If needed, it is then applied to the second leg, while ensuring that blood pressure does not rise too much.
For patients suffering a cardiac arrest, research has shown the HemaShock can help jump-start the heart. While the HemaoShock won’t provide a permanent solution, it will increase the time available for the patient to reach the emergency room.While physicians often speak of the critical “golden hour” for patients to reach the operating room for live-saving treatment, Gavriely said this can now be increased to 120 minutes.“The primary target is for medics, paramedics and ambulance personnel to have and apply it in the pre-hospital setting,” said Gavriely.“Every hospital department has a resuscitation cart where they keep all the equipment needed for treating cardiac arrests inside the hospital, so that’s another place where it will be.”The invention is currently undergoing clinical testing, primarily at Eisenhower Hospital in Palm Springs, California. The US Marine Corps, Gavriely said, have also stockpiled the device and have used it at least once in an emergency situation.The core technology is currently shared with a line of single-use products, including OHK’s HemaClear device, which is used for quick and effective displacement of blood from the limbs, to create a bloodless surgical field during orthopedic limb surgery.HemaClear, which has received FDA and CE certification, has already been used in over 1.2 million procedures in 42 countries.
