More hospital patients are surviving traumatic brain injuries - which is good news, except for those waiting on donated organs for transplants. Improved survival rates have resulted in fewer transplant organs being available, Canadian researchers found.

A study published last week in the Canadian Medical Association Journal (CAMJ), examined the recovery outcomes of 2,788 adult patients admitted to regional intensive care units in Alberta, Canada, over a 10.5 year period.

“Prior to the study, we had noticed a decline in the number of deceased organ donors in Southern Alberta,” said Dr. Andreas Kramer, lead author of the study. “Since we were seeing fewer patients with brain injuries, we thought we would find fewer patients progressing to neurological death.”

Researchers looked at ICU patients with various types of brain injuries. They found the greatest increase in survival rates were among traumatic brain injury patients.

“The reason why research like ours is important is because it helps us put our finger on the pulse of what's going on, plan ahead, moving forward with appropriate strategies," Kramer said.

Measures to improve safety, like helmets and seat belts, were found to have prevented new injuries from occurring and prevented existing injuries from progressing to brain death. Improved pre-hospital and in-hospital care are also likely contributing factors to increased survival rates, said Kramer, assistant professor of Critical Care Medicine and Clinical Neuroscience at University of Calgary, Canada.

“You can’t look at this in any other way but to celebrate better medical care,” said Dr. Thomas Pearson, executive director of the Emory Transplant Center and director of the Kidney Transplant Program at Emory University Hospital in Atlanta. While these outcomes should be celebrated, Pearson also acknowledged the potentially negative implications for transplant organ availability.

“A downstream consequence is that there are potentially fewer organs for transplant. We need to work with education and management to maximize opportunity for organ donation for those people that do succumb to brain death.”

The United Network for Organ Sharing (UNOS) defines brain death as irreversible cessation of all neurological function. When the brain is deprived of blood and oxygen flow, the brain tissue dies. However, if a patient is connected to a ventilator, allowing the heart to continue to beat and the lungs tp continue to pump air throughout the body, the organs remain healthy and viable for transplantation. An official physician-declared diagnosis of neurological death, or brain death, is required prior to organ donation in the United States.

One region in Canada is not the only area seeing a decrease in donors after brain death (DBD). Just across the border, Michigan saw a 4% decrease in brain death donors in 2012, according to Richard Pietroski, CEO of Gift of Life Michigan and Chair of the UNOS Organ Procurement Organization Committee.

There are more than 80,000 total deaths in Michigan annually, half of which occur inside hospitals, and only 350 of those in-hospital deaths are brain deaths, he said.

According to Pietroski, 86% of all deceased organ donations last year in the United States came from DBD patients. The remaining 14% were donors after cardiac death (DCD).

As more people prevent and survive brain injuries, the demographic of organ donors is shifting. After brain death, the next most common form is donation after cardiac death (DCD). The number of organs per DCD donor is typically less than the number of organs coming from a brain death donor. DCD donors are often older than and not as healthy as younger donors, so they cannot offer as many viable and eligible organs for transplant, Pearson said.

Experts agree, in the future, there will be greater emphasis placed upon living donors for single kidneys or partial organs such as the pancreas or liver. For deceased donors, researchers and doctors will need to maximize efficiency and care.

“We need to increase the number of organs we can recover from a donor, particularly a brain-dead donor.” said Kramer, adding that on average, lungs can be recovered only about one-third of the time from donors after brain death. One reason this happens is because "current methods of preservation of excised lungs do not allow extended periods of time between procurement and implantation," according to the National Institutes of Health.

New transplant technology keeps organs 'alive' outside body

Despite promising organ-donation technologies, deceased organ donors are still in short supply in the United States.

“Brain injury patients deserve to receive our best care,” Kramer said. “These individuals should never be viewed as just potential donors. Organ and tissue donation is a wonderful way for something positive to come out of a tragedy.”

“Traumatic brain injury is the leading cause of death in young people in developed countries.” he said. “If we as a society are doing a better job of preventing it in the first place, and take better care of the patients who do experience an injury, I don't see how this is anything but good news.”