MONTREAL (FRONTLINE MEDICAL NEWS) – A “hospital ecosystem score” derived from examining high-volume, high-quality hospitals has good specificity in predicting which hospitals will have high-quality outcomes, though these hospitals have low surgical volume for a given procedure.

“What we’re talking about is a care delivery macro-environment,” said Dr. Anai Kothari, presenting results of a retrospective study of surgical outcomes at the Central Surgical Association’s annual meeting.

The study built on previous work that had identified “hospital system factors that actually equipped hospitals to provide high quality care,” said Dr. Kothari, a surgical research resident at Loyola University Medical Center in Maywood, Ill. “These high-volume ecosystems do exist at low-volume hospitals,” he said.

The study was designed as a retrospective review of 24,784 patient encounters over a 5-year period from 302 hospitals; data were taken from the Hospital Consumer Assessment of Healthcare Providers and Services (HCAHPS) databases in California and Florida, with hospital resources data taken from the American Hospital Association (AHA) Annual Survey Database.

Adult patients were included if they had a malignancy of the esophagus, pancreas, or rectum, and had a surgical resection of the malignancy.

Dr. Kothari and his coinvestigators used patient mortality as a marker of quality, and analyzed the relationship between quality and case volume for each of the three procedures. “We used very strict definitions for high and low-volume” of surgical procedures, based on criteria set by the “Take the Volume Pledge” campaign that discourages surgeons from performing certain complex procedures unless they do them frequently, he said.

When procedural volume was mapped against risk-adjusted patient mortality in the data, the results could be divided into quadrants: high-volume/high-quality, high-volume/low-quality, low-volume/high-quality, and low-volume/low-quality.

Dr. Kothari said that an interesting pattern emerged, where a significant number of hospitals had low case volume but high quality outcomes. “In some cases … there are actually more low-volume/high-quality centers than high-volume/high-quality centers,” he said.

The researchers then looked at centers that performed at least two of the three surgical procedures at a high volume, to tease out some of the hospital system factors at play. They settled on examining 13 hospitals of over 300 initially studied, looking at more than 30 hospital characteristics that fell into five broad categories. These included infrastructure, size, staffing, perioperative services, and support intensity.

Within these categories, infrastructure characteristics associated with better outcomes included the facility’s being a level 1 trauma center and having transplant services. Size characteristics associated with better outcomes included total number of hospital admissions and total inpatient surgical volume. In terms of staffing, higher resident-to-bed and nurse-to-bed ratio (but not a higher physician-to-bed ratio) were both linked to better outcomes.

The perioperative services that mattered for outcomes were patient rehabilitation, geriatric services, speech and language pathology, and inpatient palliative care. Patients in facilities with a high level of oncology support also fared better.

Using different analytic models, Dr. Kothari and his colleagues attempted to determine whether these factors were predictive of a high-volume ecosystem that would result in better outcomes, even if volume for a particular procedure was low.

They found that their model, which assigned one point for each hospital ecosystem characteristic present at a given hospital, was very specific for identifying low-volume, high-quality care centers. “So a score of 7 and above has a specificity for low volume/high quality of care of over 70%” in esophageal resection, said Dr. Kothari.

Dr. Kothari noted how few high-volume centers were identified for this study, a finding that points to the practical importance for hospital administrators of knowing what factors may contribute to better surgical outcomes in smaller facilities.

Dr. Luke Funk , director of minimally invasive surgery research at the University of Wisconsin-Madison and a sometime collaborator of Dr. Kothari’s, had some suggestions for next steps. “Perhaps you could drill down qualitatively, going into some of these centers and talking to folks. Then you could take aspects from these programs and apply them to lower volume centers.” Dr. Kothari agreed, saying this would be a “very natural next step.”

Dr. Kothari reported no relevant disclosures; he is supported by an NIH training grant.

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