L A R G E B OW E L 347

nn CONCLUSION Suggested Readings

Ghassemi K, Jensen D. Lower GI bleeding: epidemiology and management.
LGIB is a complex problem arising from a variety of etiologies with a
Curr Gastroenterol Rep. 2013;15.
range of severity. Consequently, it is important for the clinician to be Gralnek IM, Neeman Z, Strate LL. (March 2017). Acute lower gastrointestinal
thorough in his or her assessment, and to be mindful of concurrent bleeding. N Engl J (Review). 2017;376(11):1054–1063.
resuscitation of the patient. Because approximately 85% of patients Green BT, Rockey DC, Portwood G, et al. (November 2005). Urgent colonoscopy
presenting with LGIB will spontaneously resolve, most patients may for evaluation and management of acute lower gastrointestinal hemorrhage:
only require some degree of resuscitation and not require procedural a randomized controlled trial. Am J Gastroenterol. 2005;100(11):2395–2402.
intervention to achieve hemostasis. Endoscopic and intravascular Jacovides CL, Nadolski G, Allen SR, et al. (July 2015). Arteriography for lower
procedures should be first line for most episodes of GI bleeding that gastrointestinal hemorrhage: role of preceding abdominal computed to-
require intervention, with surgery usually reserved only for refrac- mographic angiogram in diagnosis and localization. JAMA Surg. 2015;
150(7):650–665-6.
tory cases of brisk bleeding. Furthermore, in a hemodynamically
Kim, Charles Y, et al. Provocative mesenteric angiography for lower gastroin-
stable patient, endoscopic assessment is usually a reasonable method testinal hemorrhage: results from a single-­institution study. J Vasc Interv
of obtaining a diagnosis. Surgical intervention can also be warranted Radiol. 21(4)4”477­–483.
in the setting of neoplasia, refractory inflammatory bowel disease, Strate L, Naumann C. The role of colonoscopy and radiological procedures
Meckel’s diverticulum, necrotic intestine secondary to ischemia, or in the management of acute lower intestinal bleeding. Clin Gastroenterol
hemorrhoids. Hepatol. 2010;8:333–334.

Enhanced Recovery education as well as active engagement of all of the stakeholders that
will participate in the patient’s care along the care continuum.

After Surgery An ERAS program may be a departure from what patients have
experienced if they have had prior surgeries or even from their gen-
eral expectations if they have not. Just as the adoption of ERAS by
Alodia Gabre-­Kidan, MD, and Jonathan Efron, MD healthcare professionals requires a shift in the belief that patients who
undergo major surgery need to be hospitalized longer, the common
perception on the part of patients that surgery involves several days in

T he key tenet of an Enhanced Recovery After Surgery, or ERAS,

program is minimizing stress along the entire surgical care con-
tinuum from preoperative evaluation through postoperative follow-
the hospital for convalescence must also be adjusted. This begins with
understanding patients’ goals for surgery and educating them on the
goals of an enhanced recovery pathway. It is important to explain the
­up. This requires several shifts in the standard approach to any given benefits of the ERAS pathway beyond simply reducing length of stay
surgical patient. First, it must be accepted that outcomes depend on and avoiding terms such as fast track or expedited recovery because
more than traditional preoperative cardiopulmonary optimization these do not convey the true goals of ERAS programs. Emphasis
and surgical technique. Although we have made great advances in should be placed on decreasing complications, minimizing stress and
surgical technique, patients still suffer complications. This suggests anxiety, and guiding patients through their recovery as smoothly as
that even as we continue to innovate and push the limits of our techni- possible. To this end, educational materials on preoperative instruc-
cal capabilities, we must also look beyond what happens in the oper- tions, what to expect during their hospitalization, and criteria for
ating room to make an impact on patient outcomes. Second, as we discharge are important to provide. Some programs use printed mate-
learned from multidisciplinary tumor boards in cancer care, a mul- rials and give each patient an ERAS pamphlet to study before surgery,
tidisciplinary approach with engagement of all stakeholders involved whereas others rely on Web-­based materials. The most effective edu-
in the care of surgical patients is key. This starts, most importantly, cational tools are written at an appropriate health literacy level and
with the patients themselves and includes outpatient surgical team outline both daily milestones and overall goals for recovery (Fig. 1).
members (i.e., nurses, support staff), surgeons, anesthesiologists, and These tools not only allow patients to take an active role in their care,
inpatient care team members such as nurses, nutritionists, and physi- but also experience lower stress/anxiety and shorter hospital stays.
cal therapy. Last, but perhaps most important, the adoption of an The creation and maintenance of a successful ERAS program cen-
ERAS program requires a willingness to adopt evidence-­based care ters around a multidisciplinary, multimodal approach to care. This
that may be a departure from typical patterns of care. This is per- involves several team members, from anesthesiologists, surgeons, to
haps the most difficult and slowest step. However, as the emphasis on nurses, and spans several settings from outpatient clinics to the oper-
delivering high-­quality, lower cost care continues to grow, we must ating room and inpatient wards. For many of these team members,
constantly evaluate and evolve beyond what dogma or preference dic- the strategies used in caring for ERAS patients will signal a departure
tates to ensure that we are delivering the best patient care possible. from their usual patterns of care. Similar to patient education, each
This chapter reviews the standard elements of an ERAS program team member must be educated on the overarching goals of the ERAS
designed to minimize stress and as a result, optimize patient out- program and how his or her individual roles contribute to these goals.
comes. Past reviews have detailed each individual component of an We will not review detailed steps on how to implement ERAS pro-
ERAS program. Instead, we will outline the cornerstones of patient grams, because each implementation must be adapted to the culture
care in ERAS programs: minimizing fasting, judicious fluid admin- and protocols of each institution. The first step, however, is education
istration, and optimizing analgesia. We will also demonstrate where on the evidence that drives the various components of the pathway.
each of these factors come in to play along the care continuum. Each Later in the chapter, we will discuss audit and compliance processes
element of ERAS affects one of these key tenets to ultimately mini- to ensure that ongoing education is taking place and any barriers are
mize stress and decrease adverse outcomes. being addressed.

nn EDUCATION nn MINIMIZING FASTING

We propose that there is one additional key feature without which Perhaps the largest shift in caring for ERAS patients is the manage-
an ERAS program cannot succeed: education. This includes patient ment of their nutritional status preoperatively and postoperatively. In

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348 Enhanced Recovery After Surgery

keeping with the principle of decreasing the stress response to sur- uncomfortable, with many patients complaining of thirst and hunger.
gery, several components of the pathway are aimed at maintaining This creates additional unnecessary stress and anxiety preoperatively.
a metabolically fed state to decrease stress, which in turn decreases Patients that are malnourished need additional nutritional optimiza-
insulin resistance and catabolism. tion before surgery and would benefit from a structured plan to boost
The first intervention in an ERAS pathway aimed at decreasing their nutrition in the days and weeks leading up to surgery.
the stress response to surgery is to avoid keeping patients without The goal of minimizing stress and catabolism by encouraging oral
food or drink from midnight the night before surgery. Although the intake continues through to the postoperative period. Patients are
traditional rationale has been to decrease the risk of aspiration dur- encouraged to take liquids the evening of surgery. In several studies
ing induction of anesthesia, newer evidence from the anesthesiol- even beyond the ERAS populations, early enteral feeds have shown to
ogy community has shown that it is safe for patients to have solids have beneficial effects and decrease overall postoperative complica-
up to 6 hours before surgery and clear liquids up to 2 hours before tions. Again, in addition to decreasing patient discomfort and anxi-
surgery. This allows the opportunity for patients to enter surgery ety associated with remaining without food or water, this serves to
in a metabolically fed state. Current ERAS guidelines recommend decrease catabolism. Although some programs will advance patients
consumption of complex carbohydrate drinks up to 2 hours before to a solid or semisolid diet on the first postoperative day, others focus
the time of surgery. The advantage to this was first shown in animal on nutritional supplements. The exact diet progression is likely not
studies that demonstrated that animals sustaining surgical trauma as important as having a structured plan for patients within a given
had better responses to stress than those that entered in the metaboli- program that minimizes fasting. To this end, routine use of nasogas-
cally starved state. These findings were then confirmed when it was tric tubes is discouraged. Not only do nasogastric tubes cause patient
shown that patients taking preoperative oral carbohydrate solutions discomfort and impede mobilization, but they have been shown to
had 50% less insulin resistance and decreased loss of muscle mass, delay return of bowel function and are associated with increased pul-
suggesting that the effects were not only limited to glucose metabo- monary complications such as atelectasis and pneumonia. Last, for
lism but protein and fat metabolism as well. Subsequent studies and patients to continue oral intake, postoperative nausea and vomiting
meta-­analyses have suggested that preoperative carbohydrate loading (PONV) must be well controlled. This starts preoperatively with risk
is an independent predictor of length of stay. From a psychological stratification using scoring systems such as the Apfel score (Fig. 2)
standpoint, remaining without food or water for several hours is also and appropriate preoperative prophylaxis. All patients should receive

100%

80%
Risk factors Points
Female gender
PONV risk
1 60%
Nonsmoker 1
History of PONV 1 40%
Postoperative opioids 1
Risk score = 0...4 20%

0%
FIG. 1 Apfel’s score. PONV, postoperative nausea 0 1 2 3 4
and vomiting. No. of risk factors

• Hyperchloremic acidosis
• Pulmonary edema and
• Reduced circulating
decreased gas exchange
blood volume
• Splanchnic edema
• Increased
cardiopulmonary • Raised intra-abdominal pressure
complications • Decreased mesenteric and renal
blood flow
Postoperative morbidity

• Decreased renal
perfusion • Decreased tissue oxygenation
• Altered coagulation • Intramucosal acidosis
• Microcirculatory • Ileus
compromise Normovolemia • Impaired wound healing
• Hypoxemia • Anastomotic dehiscence
• Release of reactive • Decreased mobility
oxygen species
• Altered coagulation
• Mitochondrial
• Microcirculatory compromise
dysfunction
• Reactive oxygen species
• Endothelial
dysfunction • Mitochondrial dysfunction
• Multiple organ failure • Endothelial dysfunction
• Multiple organ failure

FIG. 2 Fluid balance. Hypovolemia Hypervolemia

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 L A R G E B OW E L 349

dexamethasone before induction, ondansetron at the completion of use of intravenous fluids with a goal of between 1.75 and 2.5 L/day.
surgery, and further interventions such as scopolamine patches based Counter to traditional postoperative care, if oral intake is tolerated,
on their risk stratification. Several other intraoperative anesthetic intravenous fluids should be decreased or entirely discontinued on
factors affect rates of PONV and will be discussed in subsequent postoperative day 1.
sections. The importance of attentive management of fluids cannot be
Despite measures to encourage early enteral feeding and decrease understated because it crosses all phases of care and involves all mem-
PONV, ileus remains a significant problem, and the most common bers of the team from patient to nurse. Improper use of fluids can
reason for increased length of stay in postoperative patients of all lead to decreased end-­organ perfusion or pulmonary/bowel edema,
types. Prompt recognition of ileus and appropriate management is both of which translate to slower recovery, increased morbidity, and
important to avoid delays in discharge and patient discomfort. increased length of stay.

nn FLUID MANAGEMENT nn ANALGESIA

Another large shift in the perioperative care of patients is the recog- Improving analgesia is an intuitive way to decrease the stress response
nition that fluid balance plays a large role in postoperative recovery. to surgery and is a cornerstone of successful ERAS programs. As
There are ample data to support the detrimental effects of both fluid opposed to a more traditional approach to pain control, ERAS pro-
overload and inadequate fluid resuscitation. The goal is to maintain grams emphasize preemptive analgesia along with a multimodal
patients in a euvolemic state by thoughtful and judicious use of intra- approach to optimize response and minimize opioid use.
venous fluids across the entire care continuum. The method of preemptive analgesia most consistently demon-
As discussed previously, patients are encouraged to take complex strated to decrease opioid use and alter the stress response to surgery
carbohydrate drinks up to 2 hours before surgery. This serves not only is thoracic epidural analgesia. An epidural catheter is placed in the
to attenuate the stress response, but also to allow the patient to main- thoracic region preoperatively and maintained through the postop-
tain fluid balance preoperatively. Another important consideration erative period usually for up to 48 to 72 hours. Early ERAS data in
in preoperative fluid management is bowel preparation for colorec- open colonic surgery showed a strong benefit to epidural analgesia,
tal surgery. The use of mechanical bowel preparation is meant to but more recent studies with a higher percentage of ERAS patients
cleanse the colon to reduce fecal spillage and subsequently decrease undergoing laparoscopy have failed to show a benefit. Epidural anal-
infectious complications such as wound infections and anastomotic gesia is also not without its complications and contraindications
leakage. The literature regarding bowel preparation is mixed and con- and requires a pain management team to follow patients postopera-
troversial, with some studies demonstrating no benefit and others tively, potentially posing a barrier to implementation. This has led to
suggesting a benefit to mechanical bowel prep combined with oral increased interest in other strategies for regional blocks such as trans-
antibiotic preparation. Strictly from a fluid management standpoint, versus abdominis plane blocks administered by either the surgical or
mechanical bowel preparation leads to large preoperative fluid losses anesthesia team before surgery. Transversus abdominis plane blocks
and patients potentially enter surgery in a hypovolemic state. This are generally performed with long-­acting anesthetic agents. There has
can lead to reflexive administration of additional intravenous fluids been increased interest in liposomal bupivacaine because it has been
to compensate for preoperative losses. Several strategies have been reported to provide analgesia for up to 72 hours after infiltration. It
advocated to minimize the routine use of mechanical bowel prepara- is unclear whether this provides additional narcotic-­sparing benefits
tion for all patients undergoing colon and rectal resections, including beyond what is traditionally used in an ERAS program. However, this
the use of enemas for rectal resection and omitting preparation for warrants further investigation because it may potentially be an avenue
right-­sided resections entirely. However, multiple other studies have to limit opioid use which is highest in the early postoperative period.
shown significant reduction in surgical site infections when mechani- In the absence of epidural analgesia, infusion of intravenous lido-
cal preparations are used in conjunction with oral antibiotics. This caine intraoperatively has been shown to improve postoperative pain
requires further investigation and is an area where variability still control, reduce opioid consumption, and is associated with quicker
remains, even within ERAS programs. return of bowel function. Evidence for preemptive analgesia with acet-
Intraoperative fluid balance is critical both within and outside aminophen and nonsteroidal antiinflammatory drugs remains unclear
of ERAS programs. Patients that leave the operating room on either but there is more evidence to support the use of gabapentinoids pre-
extreme of fluid balance are at risk for postoperative complications. operatively to decrease postoperative opioid use. Many centers also
Recent emphasis has been on avoiding fluid overload because it has use alvimopan, a peripheral mu opioid antagonist, to decrease rates of
been shown to increase adverse outcomes such as pulmonary edema ileus. There have been several studies across many surgical specialties
and ileus. Although the benefit of goal directed therapy has been dem- showing that use of alvimopan can decrease rates of ileus and length of
onstrated outside of ERAS programs, studies to date have been unable stay. Although the studies specifically investigating the benefit of alvi-
to show a benefit in ERAS programs. It is unclear if this is due to mopan in an ERAS pathway are limited, they are promising and sug-
the increased use of laparoscopy or because ERAS programs already gest that it can provide additional benefit in limiting ileus.
emphasize judicious use of intravenous fluids. Regardless, strate- Multimodal analgesia is stressed postoperatively. Use of nonste-
gies to avoid fluid overload include tight titration with intravenous roidal antiinflammatory drugs and acetaminophen postoperatively
pumps, administration of a combination of balanced crystalloids and has an opioid-­sparing effect. These medications should be used on
colloids, and use of pressors rather than fluids in hypotensive patients a scheduled basis and do not have the same effects when used as
that appear euvolemic by other clinical indicators. Several factors needed. Use of these opioid-­sparing medications also secondarily
affect intraoperative fluid balance including the use of laparoscopy, decrease rates of PONV and ileus. Decreasing PONV and ileus in
thoracic epidural anesthesia, blood loss, and insensible losses. It is turn leads to earlier oral feeding and earlier mobilization.
important that intravenous fluid is administered thoughtfully in the There are two other ERAS recommendations that affect postop-
intraoperative period because patients that enter the postanesthesia erative pain/discomfort and should be mentioned: urinary catheters
care unit and surgical wards in a state of fluid imbalance are at risk of and use of drains. Early removal of catheters, in some instances at the
deviating from the ERAS pathway. end of surgery, is encouraged. Not only does prolonged use of urinary
Meta-­analyses have shown that fluid management is an indepen- catheters increase the risk of urinary tract infection, it also causes
dent predictor of outcome in ERAS programs, and the postoperative patient discomfort and impairs mobility. In the absence of significant
period is as important to overall fluid management as the intraopera- pelvic dissection, it is recommended to remove catheters on the first
tive fluid balance. Fluid balance postoperatively should be oriented postoperative day even in the presence of epidural catheters. Routine
toward encouragement of oral intake of fluids and decreasing the intraabdominal drainage is similarly discouraged and has never been

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350 Pneumatosis Intestinalis and the Importance for the Surgeon

supported in the colorectal literature as a method of preventing or

detecting potential complications. As ERAS guidelines continue to TABLE 1 Current ERAS Guidelines
be developed for other surgical subspecialties, the literature specific Procedure and Topic Year of Publication
to that field pertaining to the use of drains will need to be reviewed. If
drains are used, early removal is advocated. Colonic resection 2012
Rectal resection 2012
nn OUTCOMES/AUDIT Pancreaticoduodenectomy 2012
The success of any individual ERAS program relies not just on the Cystectomy 2013
initial implementation of the program, but also constant assess-
ment of patient outcomes and program adherence. There is a clear Gastric resection 2014
stepwise association between adherence to the ERAS protocol and Anesthesia protocols 2015
postoperative outcomes. When more than 70% of the ERAS elements
are followed, symptoms delaying discharge, 30-­day morbidity, and Anesthesia pathophysiology 2015
readmissions are significantly decreased. It is important to have an Major gynecology (parts 1–2) 2015
ongoing audit process to ensure that goals for the program are being
met. Similarly, regular meetings with members of the ERAS team are Bariatric surgery 2016
important to discuss areas that may need improvement. Liver resection 2016
Head and neck cancer surgery 2016
nn FUTURE DIRECTIONS
Breast reconstruction 2017
Although the most robust literature regarding ERAS pertains to
colonic surgery, there has been an adoption of ERAS across several Hip and knee replacement Under production
subspecialties (Table 1). There are 12 surgical subspecialties with Thoracic noncardiac surgery Under production
separate ERAS guidelines from the ERAS Society and several more
underway. Future study should be directed at the potential benefit Esophageal resection Under production
of ERAS when applied to traditionally high-­risk surgical candidates
ERAS, Enhanced Recovery After Surgery.
such as the frail elderly population. For example, there is emerging
interest in prehabilitation programs designed to optimize preop-
erative functional capacity to better prepare vulnerable patients to
withstand the stress of surgery. The early data on these programs are
Suggested Readings
mixed, and it is unclear whether they will offer additional benefits Feldman LS, Delaney CP, Ljungqvist O, Carli F. The SAGES/ERAS Society
beyond ERAS or could be incorporated into ERAS programs. Last, Manual of Enhanced Recovery Programs for Gastrointestinal Surgery. New
the long-­term benefits of participation in an ERAS program remain York: Springer; 2015.
to be seen. Studies focusing on cancer-­specific outcomes suggest that Gustafsson UO, Hausel J, Thorell A, et al. Adherence to the Enhanced Recov-
ery After Surgery protocol and outcomes after colorectal cancer surgery.
adherence to ERAS protocols may be associated with increased 5-­year
Arch Surg. 2011;146(5):571–577.
cancer-­specific survival, but more studies of this nature are needed. Gustafsson UO, Scott MJ, Schwenk W, et al. Guidelines for perioperative care
There is no doubt that implementation and maintenance of an ERAS in elective colonic surgery: Enhanced Recovery After Surgery (ERAS) So-
program requires a large investment in resources, personnel, and time. ciety recommendations. World J Surg. 2013;37:259–284.
However, with continued adherence, the benefits are clear and provide Ljungqvist O, Scott M, Fearon K. Enhanced Recovery After Surgery: a review.
an opportunity to further improve the care of our surgical patients. JAMA Surg. 2017;152(3):292–298.

Pneumatosis Intestinalis not be related to transmural necrosis. For this reason, it is important
to note that PI should be evaluated in a clinical context that includes

and the Importance for associated examination and laboratory data so that negative explora-
tion on nontherapeutic laparotomy be avoided when possible.

the Surgeon This chapter presents an algorithm on how to identify patients

who require an operation in the context of PI.

Paula Ferrada, MD, FACS, and Joseph Dubose, MD, FACS

nn BENIGN PI
Benign PI presents as an incidental imaging finding without associ-

P neumatosis intestinalis (PI) is defined as gas-­or air-­filled cysts on

or in the bowel wall. This is a radiologic sign, not a disease, and it
can be associated with multiple factors ranging from bowel ischemia
ated clinical sequelae indicative of ischemia. For example, some con-
nective tissue disorders such as scleroderma have been associated
with formation of cysts within the bowel wall not associated with
to a mere incidental finding. For the past decade, much research has ischemia. In the case of rupture of one of these cysts, the patient can
been done to determine the significance of this sign, how to distin- even complain of abdominal pain that is self-­limited, localized, and
guish clinically when PI is pathologic or benign, and when it is the without any other clinical findings.
optimal time to perform surgery when patients have PI secondary
to ischemia. nn CLINICAL
There is a likely a difference between PI identified on plain
PRESENTATION OF
radiographs and the occurrence of this finding via more advanced
PATHOLOGIC PI
radiologic methods such as computed tomography (CT). The latter Pathologic PI is present when there is associated ischemia. This
imaging modality is more detailed and therefore can more sensitively can be associated with transmural necrosis. In pathologic PI, the
identify pathologic PI in the early stages of ischemia, when it may still patient usually presents with abdominal pain. If the abdominal pain

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