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98
D. S. Keller and L. Lee
Programs such as the American College of Surgeons National Surgical Quality
Improvement Program (NSQIP) are a useful tool to help with quality improvement
after ERP implementation. NSQIP produces risk-adjusted reports tracking institutional outcomes and can compare outcomes to both your historical and national
rates. The Enhanced Recovery in NSQIP (ERIN) program has ERP-specic variables that can be collected within the NSQIP and can be a useful tool for audit [41].
The ERAS Society has also developed an interactive audit tool specically to measure and track care processes and outcomes for ERPs [42]. For institutions without
access to NSQIP or the ability to use the ERAS Society tool, the most simple option
is to create your own report using a spreadsheet, such as Microsoft Excel, where
customized audit reports can be easily created showing overall compliance with the
individual elements of a protocol, trends over time, and even provider-specic
reports for continuous quality improvement (Fig.7.3).
After the initial implementation, effective integration with existing clinical sys-
tems, such as creating standardized electronic order sets, and using audit and feedback to report to hospital stakeholders have been identied as technical enablers to
success [17]. It is important to set a regular schedule to audit the outcomes, such as
every month initially and then every quarter, and transition the results back to the unit
champions and stakeholders. Audit of outcomes regularly allows for renement, celebrating accomplishments, and continued administrative and departmental support.
With the audit results, the team can revise the protocol, education documents, and
any other aspect of the program to meet changing needs and goals. Auditing can also
help identify outliers and patients who fail to meet expectations on an ERP to maximize identication of defects in and improve on further pathway implementation and
success [1, 43, 44]. To date, there are no standardized frameworks to guide data
Fig. 7.3 Example of creating personalized audit reports
7 Debunking Enhanced Recovery Protocols inColorectal Surgery: Minimal…
99
collection or audit or to assess the effectiveness of implementation, but an international expert consensus is underway to maximize outcomes [14].
The impact of ERP compliance on postoperative outcomes has been studied;
showing increasing compliance independently improves outcomes, with fewer
complications and shorter primary hospital length of stay [45]. The association of
compliance with improved clinical outcomes was shown specically in major
colorectal cancer surgery, indicating a dose-response relationship [46]. Thus, continued quality improvement should target increasing compliance with all elements
of the ERP. While compliance improves outcomes, ERPs are not an all-or-none
phenomenon. Non-compliance occurs mostly in the postoperative period and may
be due to lack of education, logistical issues, or medical necessity [47]. Patients will
still experience benets in clinical and functional improvement following parts of
the pathways as the team strives for complete implementation to maximize the benets [48].
Conclusions
Enhanced recovery protocols are proven to improve the clinical and nancial outcomes in colorectal surgery. Development of ERPs is commonly thought of as a
complicated, expensive, and labor-intensive practice, and while there is a large volume of literature on outcomes, there is little written on the actual implementation
science of ERPs at the institutional level. In this chapter, we moved through the
stepwise development, methods to successfully translate the ERP into clinical practice and auditing results using the minimal requirements for maximal benet. This
framework can assist all surgeons practicing colorectal surgery in the process of
dening their goals; obtaining institutional support; creating their multidisciplinary
team, business case, and specic protocols; overcoming the cultural change when
rolling out the protocols; and auditing results for ongoing quality improvement. It is
important to remember that ERPs are a process and to have patience with the results
and acceptance of the process. With time and perseverance, barriers and enablers
will be identied, and ERP will prove to be incorporated as everyday practice with
ongoing benets.
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Recovery After Surgery program implementation in Alberta colon cancer patients. Curr Oncol.
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D. S. Keller and L. Lee
Bowel Preparation inColorectal Surgery:
Impact onSSIs andEnhanced
Recovery Protocols
TraciL.Hedrick andStefanD.Holubar
Introduction andRationale
There are few topics more widely debated in the gastrointestinal surgical literature
than the use of mechanical bowel preparation (MBP) for colorectal surgery. Some
of the controversy arises from differences in practice patterns between the United
States and Europe. However, much of the discrepancy arises from methodological
differences between studies with regard to bowel preparation recipes including the
osmolarity of the cathartic and the presence or absence of oral antibiotics (OAs).
The variations in study methodology (specically with regard to the omission of
OAs) have led to misinterpretation of the data and changes in practice. As a result,
practice patterns vary widely (Fig.8.1) [1–3]. In this chapter, we will review the
evolution of the MBP including the most up-to-date literature specically with
regard to the role of MBP in the prevention of surgical site infection (SSI) and use
within an enhanced recovery protocol (ERP).
8
Efficacy ofMechanical Bowel Preparation (MBP)
inColorectal Surgery
The efcacy of the MBP combined with OAs for elective intestinal surgery was rst
demonstrated in the 1970s when the Nichols-Condon bowel preparation (typically
a clear liquid diet for 24hours followed by neomycin and erythromycin in addition
to vigorous mechanical cleansing) was described [4–6]. This demonstrated a
T. L. Hedrick (*)
University of Virginia Health System, Department of Surgery, Charlottesville, VA, USA
e-mail: Th8q@virginia.edu
S. D. Holubar
Department of Colon and Rectal Surgery, Cleveland Clinic Foundation, Cleveland, OH, USA
e-mail: holubas@ccf.org
© Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) 2020
P. Sylla et al. (eds.), The SAGES Manual of Colorectal Surgery,
https://doi.org/10.1007/978-3-030-24812-3_8
103
104
Fig. 8.1 Graphic representation of
practice patterns throughout the
United States with regard to
mechanical bowel preparation
demonstrating that 24% of surgeons
omit a mechanical bowel prep, 29%
use MBP with oral antibiotics, and
45% use MBP in the absence of oral
antibiotics. (Data from Refs. [1–3])
T. L. Hedrick and S. D. Holubar
reduction in SSI following colorectal surgery from 43% to 9%. Following this sentinel publication, the Nichols-Condon bowel preparation became the gold standard
for the following two decades with widespread, global use and adoption of this
“aggressive” cathartic prep, which was often poorly tolerated by patients [7, 8].
However, the modern use of the MBP has been called into question due to a number
of secular trends in surgery including patient satisfaction/tolerance, concern of
overall renal failure with hyperosmotic preparations, the development of broader
spectrum parenteral (IV) antibiotics, and nally the advent of enhanced recovery
programs (ERPs). As a result, there has been a proliferation of research into the
efcacy of the MBP (with or without OAs), which continues to this day (Fig.8.2).
With the development of parenteral third-generation cephalosporins and other
parenteral antibiotics, many of the MBP trials conducted in the early 2000s omitted
OAs based on the assumption that IV antibiotics would mitigate the need for OAs
[9, 10]. This was in stark contrast to the initial trials conducted during the 1970s. It
subsequently became evident that a MBP in the absence of OAs results in liquid,
bacteria-laden stool that is more likely to contaminate the operative eld than
formed stool in the unprepped colon [11, 12]. Due to the omission of OAs in a
majority of these studies, clinical trials and meta-analyses from the early 2000s
failed to demonstrate efcacy in SSI or anastomotic leak prevention with MBP [9,
10, 13–15]. In fact, the 2005 Cochrane meta-analysis suggested that, compared to
no prep at all, MBP alone may result in a higher rate of anastomotic leakage and
surgical site infection [14]. Thus, the omission of the MBP became standard practice and one of the primary tenets of the early ERP movement [16]. Many ERP
protocols to this day still recommend omission of mechanical bowel preparations
altogether. Please refer to the chapters on ERPs in colorectal surgery for more
details regarding specic protocols (Chaps. 7 and 8).
In a Cochrane Collaboration meta-analysis published in 2009, Nelson and coauthors demonstrated the importance of OAs in the presence of prophylactic IV
45
40
35
30
25
20
15
10
5
0
19731975 1977 1979 19811983 1985 1987 19891991 1993 1995 19971999 2001 2003 20052007 2009 2011 20132015 2017
8 Bowel Preparation inColorectal Surgery: Impact onSSIs andEnhanced Recovery…
Fig. 8.2 Graphic representation of the number of published manuscripts within PubMed per year
on the use of mechanical preparation prior to surgery
105
antibiotics and a MBP.Their review of 182 RCTs found that OAs administered in
the presence of a MBP in addition to IV antibiotics for prophylaxis were associated
with a 75% reduction in the rate of SSI [17]. This subsequently led to the publication of several studies evaluating the efcacy of OA combined with the MBP.Multiple
large risk-adjusted national database studies including the National Surgical Quality
Improvement Program (NSQIP) and the Michigan Surgical Quality CollaborativeColectomy Best Practices Project demonstrated signicant reduction in infectious
morbidity (SSI and anastomotic leak) associated with the use of a MBP when com-
bined with oral antibiotics [1, 18–25]. Furthermore, the addition of OAs does not
seem to increase the risk of Clostridium difcile infection and may, in fact, reduce
the risk through the prevention of SSI and subsequent need for broad-spectrum
antibiotics [26]. The recommendation for the use of a MBP in the presence of OAs
is now supported by multiple meta-analyses [27].
Taken together, these data demonstrate that a MBP alone in the absence of OAs
cannot be recommended. However, based on several prospective randomized controlled trials (RCTs) and databases studies totaling over 100,000 patients, a combination of a MBP and nonabsorbable OAs is associated with the lowest rate of
infectious morbidity following elective colorectal surgery. This distinction in the
use of MBP with and without OAs is critical when interpreting available literature
to optimize surgical outcomes [1, 2, 20, 28].
There are emerging data suggesting that OAs may be benecial at reducing SSI
in elective colorectal surgery in the absence of MBP, at least relative to regimens
without OAs [29, 30]. Several recent large NSQIP studies have examined the role of
OA prep without MBP.Atkinson and coauthors [31] conducted a study of just over
106
T. L. Hedrick and S. D. Holubar
6000 patients, demonstrating that OA alone, without MBP, was associated with a
reduction in SSI rates from 13.7% to 9.7% (p=0.01). Klinger and coauthors [23]
examined roughly 30,000 colectomy patients within NSQIP and found that while a
combined MBP with OAs was superior, OA alone was favorable to omission of
MBP in terms of SSIs. A signicant limitation of this study was that only 6% (1374)
of the cohort received OA alone, suggesting signicant selection bias.
Finally, Garnkle and coauthors [30] in a similar study with over 40,000 colectomies found that OA alone and combined OA+MBP resulted in an equivalently
low rate of SSI, leak, and ileus, suggesting that the combined prep offered no advantage over OAs alone. These studies have been included in a recent networked metaanalysis whose ndings were that overall combined MBP + OAs produced the
lowest rate of infectious complications with OAs alone as the next best option for
obtaining the lowest rate of SSIs [21]. There are no RCTs examining OAs alone
compared to other strategies. Therefore, whether or not isolated OAs in the absence
of a mechanical preparation is truly effective in reducing infectious morbidity
remains to be seen.
To assess current practice regarding current bowel prep use, the authors conducted a Twitter® poll, of mostly academic surgeons, from around the globe. This
included 141 votes from a variety of different countries and showed that a combined
MBP and OA prep is now the most commonly used preparation (59%), while 21%
of surgeons omit use of any MBP.A similar contemporaneous poll regarding sigmoid colectomies showed similar results with the addition that some surgeons prescribe enemas for left-sided procedures (Fig.8.3).
Fig. 8.3 Results of recent
Twitter (Twitter Inc., San
Francisco, CA, USA) poll
on the use of bowel
preparations by academic
surgeons
8 Bowel Preparation inColorectal Surgery: Impact onSSIs andEnhanced Recovery…
107
Bowel Preparations andLaparoscopic Colorectal Surgery
Aside from the salutary effect of MBPs on SSIs, the MBP offers a practical and
technical benet specic to intestinal surgery through decompression of the bowel.
This allows for easier manipulation of the colon, particularly with laparoscopy. In
addition, a mechanical preparation is obviously preferable should an intraoperative
colonoscopy become necessary (e.g., unable to locate the lesion intraoperatively)
which could force the decision to abandon surgery or perform an extended resection
with hopes of resecting the lesion. Thus, many colorectal surgeons who perform
mostly laparoscopic surgery, including the authors of this chapter and their respective partners, prefer a combined preparation for these reasons.
Types ofMechanical Bowel Preparations
One common misconception held by many perioperative care providers is that all
MBPs cause dehydration, electrolyte imbalance, and detrimental physiologic
effects. Although many of the early hyperosmotic phosphate-based solutions did
lead to dehydration, the isosmotic solutions in most current MBP regimens are better tolerated. Table 8.1 describes the clinical characteristics of various MBP
regimens.
In contrast to isosmotic preparations, hyperosmotic preparations such as magnesium citrate and sodium phosphate draw water into the intestine through an osmotic
Table 8.1 Various mechanical bowel preparations and their properties
Name Properties
Polyethylene glycol (PEG, GoLYTELY®
[Braintree Laboratories, Braintree, MA,
USA], Colyte® [Pendopharm, Montreal,
Canada])
Sulfate-free PEG (NuLytely® [Braintree
Laboratories, Braintree, MA, USA],
TriLyte® [Schwarz Pharma, Milwaukee,
WI, USA])
Low-volume PEG and bisacodyl
(HalfLytely® [Braintree Laboratories,
Braintree, MA, USA])
Low-volume sulfate solution (SUPREP®
[Braintree Laboratories, Braintree, MA,
USA])
Ascorbic acid lavage (MoviPrep® [Salix
Pharmaceuticals, Bridgewater, NJ, USA])
Sodium phosphate
Liquid form
Visicol® tablets (Salix Pharmaceuticals,
Bridgewater, NJ, USA)
OsmoPrep® tablets (Salix
Pharmaceuticals, Bridgewater, NJ, USA)
Magnesium citrate as adjunct to PEG Lower volume, caution in renal dysfunction
Safe, large volume, poor taste
Safe, large volume, better taste
Safe, lower volume (2L)
Low volume, risk of electrolyte abnormalities and
renal dysfunction
Safe, better taste, caution in patients with G6PD
deciency
Low volume, electrolyte and uid shifts, caution in
cardiac/liver/renal dysfunction; elderly/dehydrated,
those taking angiotensin-converting enzyme
inhibitors or angiotensin receptor blockers