Prehabilitation and enhanced recovery after surgery

Background and history

Enhancing recovery after surgery has, of course, been the goal of surgeons since the beginning of surgery. It was not until the 1990s, however, that what we now refer to as “enhanced recovery after surgery” (ERAS) began to take its more formalized, programmatic shape, initially under the name “Fast Track” surgery in a publication on coronary bypass patients showing shorter intensive care unit and overall postoperative lengths of stay in the “fast track” group managed with a bundle of pre-, intra-, and postoperative principles. Shortly later, similar reports followed, describing bundle-enhanced recovery after colonic resections. ^, Then, in 2001, the ERAS Study Group formed, gathered in London to optimize a protocol based on published evidence, met again in 2003 in Stockholm as the 1st ERAS Symposium, and in 2005 produced a consensus paper describing approximately 20 pre-, intra-, and postoperative interventions that now form the backbone of 17 specialty-specific ERAS guidelines, most with a high level of evidence, that are currently (and freely) available via The ERAS Society ( erassociety.org ), which was founded and registered as a nonprofit in 2010. Even from the earliest designs, the perioperative interventions have covered the gamut of perioperative care, from the earliest stages of patient education and prehabilitation, to beyond the end of the postoperative care of any one patient, to include—and this is essential—an audit of the ERAS process for future patients, as shown in the ERAS protocol in Table 8.1 .

Why ERAS works

If one had to identify a single source of value in ERAS, it would likely be multimodality. However, this refers not merely to the multiplicity of the modal elements in the bundle (no single modality would be expected to yield drastic results, but instead it is the combination of interventions that produces a larger benefit). Rather, a broader multimodality helps explain why the larger benefit that comes with the bundle of interventions is not merely additive, but rather is likely synergistic (meaning that, for example, 10 interventions each with a benefit of 1 hypothetical unit “add up” to >10 units of benefit). When one considers the surgical truism that “complications beget complications,” it becomes intuitive that an inverse process explains the synergy of ERAS bundles: each intervention in the bundle serves to set up all others for success. However, when one further considers the even less tangible effects of all the coordination, communication, and teamwork—among different types of care providers, different departments, the patients themselves and their families, etc.—that are required to build and run a robust ERAS program, it becomes increasingly clear that there is a further synergy that occurs as a result of “the coordinated team effort,” of the breaking down of silos to achieve a unified collaboration, of the resultant culture change that invariably accompanies the extensive process of developing an ERAS program. Of course, the degree to which this additional synergy occurs is directly proportional to the degree to which the ERAS process is developed in a substantive, deeply rooted manner, as opposed to nominally going through the motions.

The essential inclusion in the process of a way to audit the process using various metrics invokes the adage that “you can't manage what you can't measure.” While there is much useful truth here, it is important not to confuse measurability with value; indeed, many things with little to no value are highly measurable—and manageable—and countless things are intangible and largely unmeasurable but yet have tremendous value, such as culture. The ethos that develops in a multidisciplinary ERAS team coming together to break down interdepartmental silos and to build and run ERAS program is infectious throughout the institution. And the self-critical preoccupation with failure that accompanies a good audit process is a mark of a high-reliability organization.

Enhanced recovery before surgery

One of the most important aspects of ERAS is that it starts before surgery, with preoperative interventions such as prehabilitation. Rehabilitation will always be required postoperatively, of course, in the sense that any major surgical intervention will require a rehabilitation during recovery and convalescence of the patient back toward their preoperative baseline. But the shift in emphasis in the ERAS era, from re habilitation alone to pre habilitation, is essential.

It is not that prehabilitation, per se, is so important. Indeed, the evidence supporting the effectiveness of physical prehabilitation, as discussed below, is conflicting. Prehabilitation is, in fact, just another, single element in an ERAS bundle, and not an overwhelmingly effective one in isolation. What is essential about it, however, is that it is one of the first elements, and as such it sets the tone and the cadence of the entire perioperative experience. Having an operation is a significantly stressful trauma to the body, not unlike running a marathon, and just like attempting a marathon without training would be foolish, so too would having an elective major operation be, without first “training.” Indeed, all the components of an ERAS protocol share the common focus of stress: minimizing it, and maximizing the patient's ability to respond to it.