A Prospective Randomized Clinical Trial Comparing the Transversus Abdominis Plane Block (TAP) Versus Epidural Anesthesia For Enhanced Recovery Pathway Perioperative Management of Pain in Elective Colorectal Surgery
Phase: NA
Conditions: Colon Cancer, Rectal Cancer, Colonic Diverticulosis
Sponsor: Trinity Health Michigan

 
 
 
TAP Protocol - HSR 15-1618 
Cleary 
December 9, 2015 
 
 
 
 
A Prospective Randomized Clinical Trial Comparing the Transversus 
 Abdominis Plane Block versus Epidural Anesthesia for Enhanced 
 Recovery Pathway Perioperative Management of Pain in Elective 
 Colorectal Surgery 
 
 
 
 
 
NCT # 02591407 
 
 
December 9, 2015 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
TAP Protocol - HSR 15-1618 
Cleary 
December 9, 2015 
 
 
 
 
 
 
TABLE OF CONTENTS 
 
1. 
BACKGROUND INFORMATION ................................................................................................... 5 
2. 
STUDY OBJECTIVE ......................................................................................................................... 8 
3. 
STUDY DESIGN ................................................................................................................................. 8 
4. 
STUDY POPULATION ..................................................................................................................... 8 
5. 
PATIENT RECRUITMENT & CONSENT ..................................................................................... 9 
6. 
STUDY SCHEDULE ........................................................................................................................ 10 
7. 
RANDOMIZATION ......................................................................................................................... 10 
8.     DATA COLLECTION AND MANAGEMENT .............................................................................. 11 
9.     RISKS AND BENEFITS…………………………….………………….………………………….11 
10.    SURGICAL PROCEDURE DESCRIPTIONS ............................................................................. 14 
11.   STATISTICAL CONSIDERATIONS ............................................................................................ 18 
12.   QUALITY CONTROL AND QUALITY ASSURANCE .............................................................. 18 
13.  REGULATORY REQUIREMENTS………………………………………………………………22 
14   SCIENTIFIC REFERENCES……..……………………………………………………………….22 
APPENDIX………………………………………………………>……………………………………..23 
 

 
 
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Protocol Summary 
 
Full Title 
A Prospective Randomized Clinical Trial Comparing the Transversus 
Abdominis Plane Block versus Epidural Anesthesia For Enhanced 
Recovery Pathway Perioperative Management of Pain in Elective 
Colorectal Surgery  
Short Title 
TAP 
IND Sponsor (if 
applicable) 
St. Joseph Mercy Hospital Research Committee 
Principal Investigator 
Robert K Cleary, MD  
Sample Size 
176 
Study Population 
The study population will be composed of patient’s ≥ 18 years of age 
undergoing elective colon and rectal surgery for colorectal neoplasia, 
diverticulitis, and other diseases of the colon and rectum. 
Accrual Period 
Nov. 2015 – Feb. 2017 
Study Design 
Randomized trial comparing transversus abdominis plane block to 
epidural anesthesia  for  the management of perioperative pain in elective 
colorectal surgery 
 
Study Duration 
Nov. 2015 – Feb. 2018 
Primary Objective 
 
The primary outcome for this study is the Numeric Pain Score (NPS) 
for elective patients undergoing elective colorectal surgery in the 
Enhanced Recovery Pathway (ERP) program. 
Risks/Benefits 
The risks of this study are the same as those for patients receiving TAP 
blocks and epidural catheters outside of the study as well as the 
standard risks of colorectal surgery. TAP blocks and epidural analgesia 
are currently standard of care and widely employed at SJMH. 

 
 
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KEY ROLES 
 
Institution:  
 
 
St Joseph Mercy Hospital 
Address: 5301 East Huron River Drive 
Ann Arbor, MI 48104  
Contact Person: Robert K Cleary MD 
Phone Number: 734-358-9730 
Fax Number: 734-712-8151 
E-mail: Robert.Cleary@stjoeshealth.org 
 
Sponsor:   
 
 
SJMH Research Committee 
 
Individuals: 
Principal Investigator:   
Robert .K Cleary MD, Director Colon and Rectal Surgery ERI 
Institution: St Joseph Mercy Hospital 
Address: 5325 Elliott Dr. Suite 104 
Ypsilanti, MI 48197 
Phone Number: 734-358-9730 
Fax Number: 734-712-8151 
E-mail: Robert.Cleary@stjoeshealth.org 
 
 
 
Sub-investigators:  
 
 
 
 
 
 
Daniel Felling, MD 
 
 
 
Surgical Resident 
St. Joseph Mercy Hospital 
 
 
 
 
 
 
 
 
 
 
 
Cheryl Genord, R.Ph 
Pharmacist 
St Joseph Mercy Hospital 
 
 
 
 
 
 

 
 
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1. 
BACKGROUND INFORMATION  
 
Adequate peri-operative analgesia is a vital component of post-operative management for 
patients undergoing colon and rectal surgery, affecting hospital length of stay, quality of life, and 
patient outcomes. There are many options for the peri-operative management of pain after 
elective colorectal surgery.1 Randomized controlled trials have demonstrated improved 
perioperative pain management with epidural analgesia in postoperative colorectal patients when 
compared to intravenous and oral narcotic pain medications and are currently an integral 
component of Enhanced Recovery Pathway (ERP) programs. The benefit is believed to result 
from a decrease in the sympathetic overdrive that is associated with severe pain and surgical 
injury leading to decreased rates of ileus and fewer respiratory complications.2 Epidural 
anesthesia is characterized by placing an epidural catheter into the epidural space at or below the 
level of the iliac crest (distal to the end of the spinal cord) prior to surgery.  This catheter is 
secured to the patient’s back and continuous analgesia (often bupivacaine) is administered from a 
pump. Risks of epidural analgesia are uncommon and include infection, bleeding, hypotension 
and bradycardia, urinary retention, and rarely temporary or permanent neurologic deficits.4  
Other options for perioperative pain management include abdominal wall catheters placed either 
in the preperitoneal space at the time of surgery (OnQ®) or in the plane between the abdominal 
wall internal oblique and transversus abdominis muscles (TAP Block). A randomized controlled 
trial at this institution comparing epidural analgesia with the preperitoneal wound catheter pump 
(OnQ®) demonstrated that continuous epidural analgesia with bupivicaine provided better pain 
control on the day of surgery and on postoperative day one when compared to bupivicaine 
administered by the continuous preperitoneal pump.5  

 
 
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More recently, TAP Blocks that deliver bupivicaine in the plane between the internal oblique and 
transversus abdominis muscles have become popular in perioperative pain management for 
patients undergoing major abdominal open and minimally invasive surgery.6-7 The ease of 
insertion and advantage of a single injection without the need for an indwelling catheter make 
this option ideally suited for elective colorectal surgery patients. The disadvantage to this 
modality is the short duration of action. Peak levels for epidural and abdominal wall peripheral 
nerve block occur at 30-45 minutes with subsequent decrease to insignificant levels in 3 to 6 
hours. 
Bupivacaine is a local anesthetic drug belonging to the amino amide group. Bupivacaine is 
indicated for local anesthesia including infiltration, nerve block, epidural, and intrathecal 
anesthesia. Exparel® is a long acting bupivicaine local anesthetic FDA-approved for single dose 
infiltration for post-surgical analgesia.  It is bupivicaine in a liposomal suspension that 
significantly increases the duration of action. The bupivicaine in this product is attached to a 
proven product delivery platform, DepoFoam®. A single intraoperative abdominal wall injection 
treats pain at the source with reduced opioid requirements for up to 72 hours, considerably longer 
than standard bupivicaine. When used as part of a multimodal treatment ERP regimen, Exparel® 
can provide non-opioid pain control that lasts as long as the most intense postsurgical pain, 
without the need for catheters, pumps, or other delivery devices.3 Exparel® has been shown to 
provide effective postsurgical analgesia when used in TAP Blocks.8 
Because the duration of bupivicaine without liposomal suspension is short, there may be an 
advantage to using a long acting derivative such as Exparel® for TAP Blocks, especially with 
respect to decreasing narcotic pain medication needs after the first postoperative day.  

 
 
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This study compares two well-established treatment options within the context of a colon and 
rectal surgery ERP. Though both of these pain management options are utilized on a daily basis 
and considered standard of care in colorectal surgery, these two important pain treatment options 
have not yet been compared in a randomized controlled prospective trial. Epidural catheters are 
widely used for elective colon and rectal surgery and have the rare risk of central nervous system 
infections. If TAP Blocks are shown to be as effective as epidural analgesia in a randomized 
controlled study, this may result in a significant change in pain management for this patient 
population with the decreased associated risk. A significantly larger group of patients will likely 
receive Exparel® TAP Blocks rather than epidural catheters with the associated decrease in risk. 
Exparel® TAP Block would also be a reasonable option for those who are not candidates for 
epidural catheters (spinal stenosis, spinal fusion, patient refusal). 
The outcome of this study will be considered meritorious scholarly activity and will be published 
in a peer-review journal. It will serve as a template for other surgical pain management programs 
at other institutions. 
Pain Management in the field of colon and rectal surgery is rapidly changing and is undergoing 
constant re-evaluation. New information from this study will add considerably to the 
advancement of pain management programs in this field. 

 
 
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2. STUDY OBJECTIVE 
The primary outcome is this study is the well-established Numeric Pain Score (NPS). A 
secondary outcome is the Overall Benefit of Analgesic Score (OBAS).  This score was 
developed and validated by Lehman, et. al in 2010.9  OBAS is a comprehensive pain score that 
includes the variables of vomiting, dizziness, and sweating (Appendix 1).  
Other secondary outcomes include perioperative narcotic requirements measured in morphine 
equivalents, hospital length of stay, time to first flatus, time to first bowel movement, and 
institutional costs of TAP and epidural interventions. 
 
 
3. 
STUDY DESIGN 
This is a physician-generated single-center randomized trial comparing TAP block to epidural 
analgesia for the perioperative management of pain in elective open and minimally invasive 
(laparoscopic and robotic) colorectal surgery. 
 
4. 
STUDY POPULATION 
 
Inclusion Criteria 
 
• Patients undergoing elective open and minimally invasive (laparoscopic and robotic) 
colon and rectal surgery for colorectal neoplasia, diverticulitis, and other diseases of the 
colon and rectum; 

 
 
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• Surgical procedure either through standard open or minimal invasive approach 
(laparoscopic or robotic); 
• Patients > 18 years of age;  
• Able to provide informed written consent 
• Patients capable of completing questionnaires at the time of consent 
Exclusion Criteria 
 
• Documented allergic reaction to morphine, hydromorphone, lidocaine, bupivicaine and/or 
fentanyl; 
• Contra-indication to placement of epidural catheter (spinal stenosis, spinal fusion, elevated 
INR, anticoagulation, patient refusal, etc) or TAP block (patient refusal); 
• Urgent or emergent surgery precluding epidural catheter placement or TAP block; 
• Systemic Infection contraindicating epidural catheter placement or TAP block; 
• Unwillingness to participate in follow up assessments; 
• Prisoners 
• Pregnant women 
 
5. 
PATIENT RECRUITMENT & CONSENT 
 
Due to the nature of this study; participants, nursing staff and the research team will not be 
blinded to randomization method.  Standard analgesic options will be discussed with patients by 
the surgeons along with operative options, risks, and benefits, prior to scheduling operative 
intervention and per routine. The well-established Enhanced Recovery Pathway Program (ERP) 

 
 
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consists of patients with diseases of the colon and rectum seen in the surgeons clinic and 
inpatients on the Patient Care Unit.  The ERP Nurse Navigator will review patient's records to 
determine which patients meet inclusion/exclusion criteria and are eligible to participate in the 
study. During the current pre-operative education classes, within ERAS, the Nurse Navigator 
will approach eligible patients and discuss the study. If the patient is interested, they will be 
given the opportunity to read the informed consent and ask questions regarding the study.  
Should they be willing to participate, the Nurse Navigator will obtain informed consent.  Patients 
may also be consented in the surgeon's clinic by a research coordinator or investigator. 
Informed consent and patient logs will be stored in the academic research department.   
 
6. 
STUDY SCHEDULE 
Patients will be asked their NPS and OBAS following consent during pre-operative education 
(baseline).  NPS will then be obtained on operative day (0) and post-operative days 1, 2, and 3 
from the electronic medical records that are documented by the patient care technicians every 8 
hours. The OBAS will be collected by trained residents and nursing staff once a day on operative 
day (0) within 6 hours of recovery and between 0600 and 1200 on post-operative days 1, 2 and 3. 
 If the patient is consented in the investigators office, pre-operative NPS and OBAS will occur 
there.   
 
7. 
RANDOMIZATION  
 
Two hundred patients will be randomized in blocks of ten with a 1:1 ratio.  Standard open and 
minimally invasive (laparoscopic and robotic) approaches will have separate blocks.  Patients 

 
 
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will be randomized using a web-based system called CREDIT.  CREDIT maintains a patient log 
that includes randomization placement.     
Randomization schedules were created using R (version 3.2.1), using 10 blocks were each 
selected has a 50% chance of being selected.  The randomization process was conducted using 
box-muller to assign random numbers which was used to identify the selected treatment for each 
patient.   
8.   DATA COLLECTION AND MANAGEMENT  
Demographic, health, and hospital stay data will be obtained from the Quality Institute. Data that 
is unavailable through electronic queries will be collected from the electronic medical record by 
a study team member.  A pharmacist will collect PCA pain medication data that cannot be 
obtained from an electronic query of Pharmacy databases.   All data will be entered into 
REDCap by a research study team member.  Data will be stored in a locked office and password 
protected computer.  Only members of the study team will have access to patient identifiers.   
Identifiers will be removed prior to analysis.  All identifiers will be stored by the research 
coordinator in a secure location.   Identifiers will be destroyed seven years following the 
conclusion of this study. (Data collection sheets, including adverse events Appendix 2).  
9. RISKS AND BENEFITS 
Patients will have no direct benefit from participating in this study.  Both perioperative pain 
management treatment options are standard of care at SJHM. Exparel® is approved by the FDA 
for abdominal wall infiltration for perioperative pain management, but is not on pharmacy 
formulary at this institution because of cost. If this study demonstrates benefit to Exparel® 
utilization in TAP Blocks, it will very likely become formulary. 

 
 
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Listed below are the descriptions and risks of TAP block with Exparel® and epidural.  
 
 
TAP Block 
 
Exparel®: General 
Bupivicaine is a local anesthetic commonly used and standard of care for pain management with 
epidural catheters and transversus abdominis plane regional blocks. Exparel® is a long acting 
form of bupivicaine. The Exparel® dose used is 266 mg.  The adverse event profile is as follows: 
The most commonly encountered acute adverse experiences to bupivacaine and all amide-type 
local anesthetics that demand immediate counter-measures are related to the central nervous 
and cardiovascular systems.  High plasma concentrations of bupivacaine can occur from 
overdosage, unintended intravascular injection, or accumulation of bupivacaine in plasma 
secondary to decreased hepatic metabolic degradation of the drug or diminished plasma protein 
binding capacity due to acidosis, pathologically lowered plasma protein production, or 
competition with other drugs for protein binding sites. Although rare, some individuals have a 
lower tolerance to and are supersensitive to bupivacaine and other amide-type local anesthetics 
and may rapidly develop signs of toxicity at low doses. 
Please see attached Exparel® prescribing information/package insert.  
Epidural 
The progression of pain fibers blocked by local anesthetics in the epidural space proceeds in the 
following order from first to last; sympathetic tone, pain, temperature, proprioception, touch and 
finally motor.  As a result there is a dose-dependent relationship between epidural-based local 
anesthetics and hemodynamic effects, as well as pain control. Sympatholytic dermatomal spread 
exceeds that of both pain control and that of motor blockade. Significant hemodynamic changes 

 
 
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can result, as venous capacitance increases in the dermatomes blocked. This may result in 
potential hypotension if intravascular volume is not increased to match this hemodynamic effect. 
When the dermatomal levels include the cardiac accelerator fibers above T6, bradycardia can 
also result. 
In addition to hemodynamic changes, there are several other potential complications associated 
with epidural catheters. Inadvertent dural puncture occurs with an incidence ranging from 1-
10%. The consequence is a positional headache, requiring the patient to lay supine until 
symptoms reside. Treatment is usually conservative, however epidural blood patch may be 
offered if symptoms are refractory to bed rest. Rare but more consequential complications 
include epidural hematoma and abscess. The American Society for Regional Anesthesia (ASRA) 
has published restrictions for epidural catheters based on INR, platelet count, and the presence of 
certain anticoagulants. Epidural abscess can result from epidural placement in a systemically 
infected patient. Lastly, neuropraxia may result from epidural catheters. However the incidence 
of this complication is both rare and self-limited (less than 30 days). 
Opioids are also used with local anesthetic (LA) in the epidural space for analgesia.  Opioids cross the 
dura rapidly and enter the spinal cord, where it binds with strong affinity to the opioid receptors in the 
substantia gelatinosa.  The lipid solubility is a very important factor that effect the passage of opioids 
across the dura.  Lipid-soluble drugs penetrate the spinal cord rapidly.   Fentanyl is the commonly used 
opioid in epidurals  due to it is a potent lipid soluble opioid with a strong affinity for the opioid receptor.  
Because of the reduced cephalic spread there are less opioid side effects with fentanyl.  Pruritus is the 
most common side effect, while nausea and vomiting are less common.  Respiratory depression is very 
rare and are usually associated with the use of other systemic opioids or its accumulation from an 
infusion.  

 
 
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10. SURGICAL PROCEDURE DESCRIPTIONS  
TAP Block 
The technique has evolved from a blind, change-of-resistance method based on surface anatomy 
to an ultrasound-guided technique, allowing for real-time identification of anatomic landmarks 
and visualization of local anesthetic spread between the internal oblique and transversus 
abdominis aponeuroses following injection. For midline incisions and laparoscopic surgery, a 
bilateral injection technique is advocated.  
 
TAPB relies on the injection of local anesthetic (LA) in the fascial plane between the internal 
oblique and transversus abdominis. This plane contains the anterior rami of spinal nerves T7-L1, 
anatomically bounded cranially by the inferior costal margin, and caudally by the iliac crest. 
These anterior rami terminate in the anterior cutaneous tissue of the abdomen, rectus abdominis 
muscle, and peritoneum. In the lateral-anterior direction, the mid-axillary line is the starting point 
for needle insertion. Cadaveric studies have shown that when LA is injected below the 
umbilicus, it spreads from L1 to T10 superiorly. Supra-umbilical analgesia to T7 can be obtained 
with an infracostal injection point.  
 
 
Using the ultrasound-guided method, the patient is positioned supine. The abdomen is prepped 
and draped in a sterile fashion, with focus on the region between the iliac crest and inferior costal 
margin. The ultrasound probe is utilized to scan starting at the mid-axillary line, until the 
peritoneum and abdominal muscles are identified.  A four-inch needle is inserted in this plane, 
until placement between the tranversus abdominis (TA) and internal oblique (IO) is confirmed 

 
 
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by ultrasound. Care must be taken to avoid peritoneal, hepatic, and pleural puncture. 
Confirmation of needle placement often requires hydrodissection to establish separation of TA 
and IO muscle layers. Because the nerves follow the plane of needle insertion, analgesia from 
TAPB relies on volume spread of LA.  It is therefore important for the practitioner to select an 
LA concentration that would allow for the safe injection of 20-25cc per side. 
 
 
Although TAPB may be accompanied by catheter placement, the block is usually performed in 
the single-shot fashion. For the purpose of this study, we will use Exparel up to 266mg; as a 
1.3% solution that will be diluted to a final volume of 40cc with preservative free normal saline 
for safe injection (total 20cc or 133mg each side). TAPB with Exparel will be expected to 
provide up to 72 hours of somatic pain. There is no hemodynamic perturbation associated with 
the block, and therefore, there is no change in intravascular loading conditions. Neurovascular 
injury associated with TAPB is exceedingly rare, and when it does occur, the consequences are 
minimal – sensory and minimal motor block may occur.  This is in contrast to epidural 
anesthesia, which can result in severe sensorimotor deficit. Because there is no sacral 
involvement with TAPB, bladder catheterization is not required.   
 
Potential rare complications of TAPB include peritoneal puncture, hepatic puncture, splenic 
puncture and inadvertent femoral nerve blockade. Ultrasound guidance should minimize the 
incidence of inadvertent solid organ puncture. However, femoral nerve blockade may result even 
from a technically sound TAPB because fascia iliaca communicates with the transversalis fascia. 
Other complications include LA toxicity, bleeding, bruising and localized infection. 
 

 
 
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Surgical pain refractory to a technically successful TAPB is typically visceral or neuropathic in 
nature, largely due to inflammation that exceeds the dermatomal coverage of the block.  Pain 
may also originate in the upper abdomen, as T7-10 may be insufficiently covered. Typically, 
non-narcotic adjuncts such as acetaminophen and gabapentin may be required to provide full-
spectrum coverage of the pain associated with laparoscopy or peritoneal surgery.  
 
Single shot TAPB for colorectal surgery is standard and customary at this time in the well-
established SJMH Enhanced Recovery Initiative. This modality provides analgesia within the 
context of early mobilization, absence of invasive catheterization, and absence of hemodynamic 
perturbation.  
Epidural 
Epidural analgesia is commonly employed for abdominal surgery. Like the TABP, a low thoracic 
epidural catheter is routine and customary in our practice, and has been effectively used to 
manage perioperative pain associated with colorectal surgery. In the perioperative period, it 
provides the patient with surgical site-specific pain control without the systemic side effects of 
opiate medications. Furthermore, its sympatholytic effects are thought to counteract the ileus 
induced by surgical manipulation of the bowel. Lastly, the dose can be titrated to achieve the 
precise sensorimotor blockade required in the postoperative period via a catheter-based infusion. 
 
Epidural Catheterization (EC) relies on the fact that nerve bundles arising from the spinal cord 
reside in the epidural space. This is a potential space separated from the intrathecal space by the 
dura. Presynaptic nerve fibers reside in the epidural space, where they provide sensorimotor 

 
 
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innervation from C2 to S4. Opioids placed in this space migrate vertically and laterally, 
dependent on volume, concentration, and placement of the needle or catheter.  
 
The patient is placed in the sitting position for the epidural technique. After the back is prepped 
and draped in a sterile fashion, an 18 gauge Touhy needle is advanced following LA infiltration 
of the skin. The Touhy needle is advanced under loss of resistance technique after it is placed in 
the longitudinal ligament. Following puncture of the ligamentum flavum, the loss-of resistance 
should be obtained. The catheter is threaded into the space, and intrathecal (IT) or intravenous 
(IV) catheter placement is ruled out by test dose (3 cc of 1.5% lidocaine + 5mcg/cc epinephrine). 
Patient cooperation is required to achieve proper positioning, as well as to rule out potential 
symptoms of LA toxicity.  
 
At this center, we use fentanyl, 5 mcg/ml, and bupivicaine, 0.0625%. As a result we have 
achieved sufficient pain control without severe hemodynamic and motor effects. We can then 
adjust the rate of infusion to match the incisional coverage necessary for functional analgesia.  
 
EC is an effective modality for pain control for both open and laparoscopic bowel resection. It 
allows titration of somatic, visceral, and neuropathic pain, as well as sympatholysis. Relative to 
TAPB, it requires closer hemodynamic, fluid, and neurologic surveillance. Close attention to 
anticoagulant administration must be maintained, as well as ambulatory precautions. In deciding 
the optimal regional anesthetic for abdominal surgery, the considerations of optimal pain control, 
risk profile, and surveillance burden must all be weighed. The risk-benefit profile is such that 

 
 
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epidural analgesia is considered safe and effective and is standard and customary at most 
institutions across the world, including SJMH. 
 
11. STATISTICAL CONSIDERATIONS  
 
The power analysis using NPS scores, we have an effect size of 0.430, which is an index of the 
size of the mean differences between each day relative to the standard deviation, which is the 
magnitude of differences among the means for each day over the random variation that is 
compared to using the F test.  The relative difference among the means is 0.430, which is 
difference in means of 0.43 between each day divided by an f-test standard deviation of 1 (0.22/1 
≈ 0.418).  The mean NPS scores vary from day to day, therefore an intervention would need to 
result in a level of improvement beyond this expected level of variability.  This baseline level of 
variability is represented by an NPS score of 3.6 and so an effective intervention should result in 
a difference of at least 0.43 compared to the control group.  This results in a change greater than 
3.63 or less than 2.77 on the point NPS scale.  To detect a variation among the mean NPS scale 
of 0.43 with a power of 0.98, we will need a sample size of 176, of which 53 are lap (30%) and 
123 (70%) are open, and 10% (16) was calculated in for anticipated dropouts. All sample size 
analysis is performed in PASS 13 (Power Analysis and Sample Size System, 2011, Kaysville, 
Utah). 
 
12.  QUALITY CONTROL AND QUALITY ASSURANCE 
 
The research coordinator will meet with the principal investigator monthly during patient 
enrollment to review the progress of the study and adherence to the study protocol.   
13.    REGULATORY REQUIREMENTS 

 
 
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Approval for the Institutional Review Board at Saint Joseph Mercy Health System will be 
completed prior to the initiation of this research.  All study team members have completed the 
CITI research-training program.   
14.  SCIENTIFIC REFERENCES 
1. Block BM, Liu SS, Rowlingson AJ, et al. Efficacy of postoperative epidural analgesia: a  
meta-analysis. JAMA 2003;290:2455-2463. 
2. Gendall KA, Kennedy RR, Watson AJ, Frizelle FA (2007). “The effect of epidural analgesia 
on postoperative outcome after colorectal surgery”. Colorectal Dis. 200 Sep:9(7):584-98; 
discussion 598-600 
3. Mouawad NJ, Leichtle SW, McCord M, Hoskins K, Welch KB, Lampman RM, Cleary RK. Is 
continuous preperitoneal analgesia effectively equivalent to continuous epidural analgesia for 
pain control after colorectal surgery? Manuscript in preparation. 
4. Keller DS, Ermlich BO, Schlitz N, Champagne BJ, Reynolds HL, Stein SL, Delaney CP. The 
effect of Transversus Abdominis Plane blocks on postoperative pain in laparoscopic colorectal 
surgery: a prospective, randomzied, double-blind trial. Dis Colon Rectum 2014;57:1290-97 
5. McDonnell JG, O’Donnell B, Curley G, Heffernan A, Power C, Laffey JG. The analgesic 
effect of Transversus Abdominis Plane block after abdominal surgery: a prospective controlled 
trial. Anesth Analg 2007;104:193-7 
6. Ventham NT, O’Neill S, Johns N, Brady RR, Fearon KCH. Evaluation of novel local 
anesthetic wound infiltration techniques for postoperative pain following colorectal resection 
surgery: a meta-analysis. Dis Colon Rectum 2014;57:237-5 

 
 
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7. Candiotti KA, Sands LR, Lee E, Bergese SD, Harzman AE, Marcet J, Kumar AS, Haas E. 
Liposome bupivicaine for postsurgical analgesia in adult patients undergoing laparoscopic 
colectomy: results from prospective phase IV sequential cohort studies assessing health 
economic outcomes. Current Therapeutic Research 2014;76:1-6 
8. Lehmann N, Joshi GP, Dirkmann D, Weiss, M, Gulur P, Peters J, Eikermann M.  
Development and Longitudinal Validation of the Overall Benefit of Analgesia Score: A Simple 
Multi-Dimensional Quality Assessment Instrument. BJA 2010. 
 
 
 
 
 
APPENDIX 1.  Overall Benefit of Analgesia Score (OBAS)  
 
Patient Name________________________________ Time____________ 
 
FIN________________________DOB______________Date of Surgery__________________ 
 
Please circle correct day. 
 
0. Pre-op  
1. POD 0 
2. POD 1 
3. POD 2          4. POD 3 
 
1. Please rate your current pain at rest: 
Minimal Pain 
 
 
 
Maximum 
imaginable Pain 
0 
1 
2 
3 
4 
2. Please grade any distress and bother from vomiting in the past 24 hours: 
Not at All 
 
 
 
Very Much 
0 
1 
2 
3 
4 
3. Please grade any distress and bother from itching in the past 24 hours: 
Not at All 
 
 
 
Very Much 
0 
1 
2 
3 
4 
4. Please grade any distress and bother from sweating in the past 24 hours: 

 
 
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Not at All 
 
 
 
Very Much 
0 
1 
2 
3 
4 
5. Please grade any distress and bother from freezing in the past 24 hours: 
Not at All 
 
 
 
Very Much 
0 
1 
2 
3 
4 
6. Please grade any distress and bother from dizziness in the past 24 hours: 
Not at All 
 
 
 
Very Much 
0 
1 
2 
3 
4 
7. How satisfied are you with your pain treatment during the past 24 hours? 
Not at All 
 
 
 
Very Much 
0 
1 
2 
3 
4