Evidence review helps to understand enhanced recovery after vascular surgery

A recent evidence review on enhanced recovery after surgery (ERAS) is helping those in the field understand the clinical effectiveness of current best practices, and where there are gaps in knowledge and evidence.

The Southern California Evidence Review Center, directed by Susanne Hempel, PhD, professor of clinical population and public health sciences, gathers and synthesizes information from various published sources and provides reports to commissioning organizations like federal funding agencies and nonprofits. The research team must not have any conflict of interest – such as industry sponsored research – to take the case. “The way I always explain what I do, is I answer other peoples’ questions,” explains Hempel of her contract-based work. “The questions come to us.”

In the case of enhanced recovery after vascular surgery, Hempel’s center was contracted by the Patient-Centered Outcomes Research Institute to look at evidence base around current interventions, a topic suggested by the Society for Vascular Surgery.

Vascular surgical procedures can run the gamut, with some done under local anesthetic and more invasive procedures requiring a hospital stay. Hempel surmises that perhaps due to this wide range, there are gaps in knowledge when it comes to effective interventions for recovery.

Hempel and her team looked at randomized controlled trials focused on outpatient and inpatient vascular surgeries. Her review is unique in mapping interventions by surgical stage. They found that most interventions were administered at the preoperative (30%) or intraoperative (46%) stage. The team found that additional research around preadmission interventions is needed and noted the need for more consistent reporting of key outcomes such as hospital and intensive care unit stays. “A lot of studies did report on mortality,” comments Hempel, “that’s one of the things we know a lot about now.”

Sources included PubMed and the Cumulative Index to Nursing and Allied Health Literature (CINAHL). Publications included in the review were restricted to randomized clinical trials to produce a report citing evidence-based practices, and were processed in duplicate to ensure against human error and bias. “We have procedures in place to be able to process such large numbers,” says Hempel. “There is not room for error.“

The synthesizing Hempel and her team do is crucial to the production of evidence-based guidelines for clinical practice. Hempel points out that effective guidelines in areas like enhanced recovery after surgery are a win-win-win – benefitting the patient, providers and health systems involved in a procedure, with the additional factor of cost savings for all parties.

To reap these benefits – which foremost include providing the best possible outcomes for patients – providers and health organizations must continually evaluate and evolve recommendations. This requires determining if customary best practices stand up to the rigor of clinical trials, or if they have simply been in practice historically.

Hempel says it is not unusual to initially find thousands of publications on a broad topic such as vascular surgery – in this case 4,483 – however after applying review criteria the team identified 76 randomized control trials as relevant. She notes this is typical. “If I want to know how much time people stay in the hospital, for example, despite all the literature, as soon as you narrow it down to something specific you are left with just a few studies,” Hempel explains. “There are still so many topics where we have little empirical evidence.”

In her work with enhanced recovery after vascular surgery and other health topics, Hempel and her team often pinpoint knowledge gaps that need to be filled.

When it comes to recommendations given to patients before, during and after vascular surgery, a question that Hempel poses – “How do they know that this is really better?” – is one her work can provide answers to.

About the review

Additional authors of the review include Eric A. Apaydin and Aneesa Motala of the Keck School of Medicine of USC, Karen Woo of University of California, Los Angeles, and Julia Rollison and Sangita Baxi of the RAND Corporation.

The review was commissioned by the Patient-Centered Outcomes Research Institute (PCORI).