The Free Press, Mankato, MN

February 24, 2014

Mankato doctor part of stroke study

Research focused on 'very large' strokes

By Robb Murray

---- — MANKATO — A Mayo Clinic Health System doctor is part of a medical team that has authored some groundbreaking research on strokes.

Douglas Chyatte, a Mayo Clinic Health System neurosurgeon, helped conduct research for and was one of the authors of a study showing that by using a consistent set of protocols while treating victims of large strokes, mortality rates can be cut dramatically.

"I think our findings are significant because they really change how we think about this group of very sick patients and how we're going to treat this group of very sick patients," Chyatte said.

For patients who have experienced a large stroke that cuts off blood supply to a large part of the brain, the use of standardized medical management protocol and surgery to decompress swelling can improve life expectancy, the researchers found in their study.

The medical protocol provided each patient with consistent procedures for airway management, ventilator settings, blood pressure control, fluid and electrolyte management, gastrointestinal and nutritional management, hematologic monitoring and management, intracranial pressure monitoring, sedation, use of medication, anticonvulsants, prevention against deep-vein thrombosis and rehabilitation.

Surgery involved removing a large portion of the skull over the area of the stroke to provide extra room for the brain swelling. This reduced pressure in the head and, consequently, risk of death. For surviving patients, the piece of skull was replaced via a second surgery after swelling subsided.

Only about 1 percent of strokes qualify as "very large" strokes.

"Our study focused on those really large strokes because, prior to doing this, the outlook for those patients was very grim," Chyatte said. "Most literature suggests 80 percent of those people die."

The protocols the research used were developed by a team of experts. They decided that, for this study, a specific set of treatments would be used for stroke patients, a flow-chart so to speak that dictates what is to be done when patients exhibit certain behaviors.

They found that not all patients were really at high risk of mortality. Using clinical criteria and imaging, they were able to determine which ones were. Then, using set of standardized protocols, they were able to improve the outcomes of those who were at high risk.

Finally, on the issue of surgery, Chyatte's research group found that, "When we examined surgery, there was a positive trend in reducing mortality in this group of patients.”

Currently there are guidelines set up, but not a clearly stated set of protocols. Chyatte said he hopes their research prompts hospitals to look at their findings and consider adopting them.

The study included 20 hospitals and screened about 5,000 patients. Of those, they found 66 had these large strokes. Of those, 40 agreed to participate in the study. Chyatte began his work with group in 2005.