Complex patients less likely to die at high-volume stroke centers

Brain hemorrhage survival was highest among patients taken to high-volume stroke care units, according to findings published in the November issue of Neurosurgery. Comprehensive stroke centers and other high-volume stroke care units had the fewest subarachnoid hemorrhage in-hospital deaths, researchers found

Patient length of stay was longer on average for these high-volume hospitals compared to those with lower annual volume as well.

The research team led by Shyam Prabhakaran, MD, MS, of the neurology department at Northwestern University in Chicago, utilized Get with the Guidelines: Stroke data with an eye toward outcomes for in-hospital mortality, length of stay, discharge destination and ambulatory status. The nationwide database included patient data from 685 hospitals. Prabhakaran et al obtained data for 31,973 patients from 2003 through 2012.

They determined that as subarachnoid hemorrhage case volume increased, in-hospital mortality decreased. Hospitals where four to 6.6 patients were seen a year had a mean in-hospital mortality rate of 29.5 percent. On the opposite of the scale, care centers with a case volume of 12.6 to 93.2 patients per year had in-hospital mortality rates of 22.1 percent. Adjusting for patient and hospital characteristics, analyses showed a one-fifth lower mortality risk between the highest and lowest volume of subarachnoid hemorrhage patients.

Prabhakaran et al noted that this translated into a 7.3 percent absolute reduction in mortality in hospitals with the highest volume, with a 21 percent relative odds reduction free of hospital or patient factors.

Patients at higher volume hospitals had stay lengths that ranged between three to nine days longer than those with lower volumes, but appeared to have slightly better outcomes. The likelihood of patient discharge to home or ability to ambulate independently increased marginally between the lowest and the highest volume centers, but were largely similar.

The research team suggested that the longer stays associated with higher-volume centers may relate to more aggressive care, but they were unable to point to specific interventions or services that would differ, as these were not recorded in the database.

Prabhakaran et al wrote that their data did not support thresholds, but instead suggested a graded relationship between volume and in-hospital mortality, where in a 3 percent relative reduction occurred for every five cases.

These findings, they wrote, supported regionalized care through Comprehensive Stroke Centers. With these centers' increased volume, physician expertise and key resources, patients would receive better care for complex stroke cases, such as subarachnoid hemorrhage. Prabhakaran et al suggested these findings be considered when developing regional policies and procedures.