Referring patients to hospitals that have the largest volume of surgical procedures does not necessarily lead to improved outcomes for the overall population, according to a study in the February issue of the Journal of the American College of Surgeons.
The findings of studies that suggest the higher the volume of specialty surgical procedures performed at any given hospital, the better that hospital's outcomes will be, has resulted in calls for volume-based referrals. Most notably leading that call has been the Leapfrog Group's Evidence-Based Hospital Referral (EBHR) program, which launched a decade ago.
Nader N. Massarweh, MD, MPH, a surgical resident at the University of Washington School of Medicine in Seattle, and colleagues hypothesized that volume-based referrals would "regionalize" patients to hospitals meeting an EBHR volume metric and that, as a result, overall patient outcomes for these procedures would improve on a statewide basis.
Researchers conducted a before and after cohort study of 13,157 adults (1994 to 2007) who underwent pancreatic or esophageal resection or abdominal aortic aneurysm (AAA) repair in Washington state. They assessed rates of adjusted mortality, readmissions and complications before and after the introduction of EBHR.
Researchers found that between two and six hospitals met the EBHR volume metric in any year. They also found that the proportion of patients treated at hospitals meeting the EBHR volume metric for a given procedure significantly increased for pancreatic (59.4 vs. 75.7 percent) and esophageal (41.5 vs. 59.2 percent) resection, but not for AAA repair did not (16.3 vs, 17.6 percent).
"In general, rates of adverse events were lower at hospitals meeting an EBHR volume metric. However, across Washington state and at non-EBHR centers, rates of mortality, readmissions and complications generally did not improve in the seven years after introduction of the EBHR initiative," Massarweh and colleagues found.
According to the study, the implications of Leapfrog's EBHR program for the healthcare system include: limiting patient flow and critically important revenue at smaller hospitals; decreasing surgeon competence and availability for emergency care at lower volume hospitals; providing fewer opportunities for surgical residency training at lower volume centers; and biasing patients toward higher volume centers for procedures not related to the EBHR initiative.
"It remains to be determined why regionalization for AAA repair has not occurred and why regionalization trends in pancreatic and esophageal surgery have not had the intended impact of improving overall safety outcomes," the authors concluded.