Transversus Abdominis Plane Blocks With and Without Dexamethasone: A Randomized Clinical Trial in Minimally Invasive Colorectal Surgery
Phase: PHASE1
Conditions: Colorectal Disorders, Regional Anesthesia Morbidity, Analgesia, Local Anesthetic Complication, Pain, Postoperative, Colorectal Cancer, Crohn Disease, Diverticular Diseases
Sponsor: University of Saskatchewan

TAP-DEX: Transversus Abdominis Plane Blocks with and without Dexamethasone: A Randomized 
Clinical Trial in Minimally Invasive Colorectal Surgery 
 
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STUDY PROTOCOL 
 
 
 
 
Transversus Abdominis Plane Blocks with and without 
Dexamethasone: A Randomized Clinical Trial in 
Minimally Invasive Colorectal Surgery 
 
 
 
 
 
BIO-2549; Sept 22 2021 
 
Dr. D. Nathan Ginther 
Department of Surgery  
University of Saskatchewan 
Room 151 Ellis Hall 
103 Hospital Drive, Saskatoon, SK 
S7N 0W8 Canada 
 
 

TAP-DEX: Transversus Abdominis Plane Blocks with and without Dexamethasone: A Randomized 
Clinical Trial in Minimally Invasive Colorectal Surgery 
 
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PROTOCOL 
 
Table of Contents 
 
BACKGROUND INFORMATION 
3 
TRIAL OBJECTIVES AND PURPOSE 
5 
TRIAL DESIGN 
5 
SELECTION AND WITHDRAWAL OF SUBJECTS 
6 
TREATMENT OF SUBJECTS 
6 
ASSESSMENT OF EFFICACY 
10  
ASSESSMENT OF SAFETY 
10 
STATISTICS 
10 
DIRECT ACCESS TO SOURCE DATA / DOCUMENTS 
11 
QUALITY CONTROL AND QUALITY ASSURANCE PROCEDURES        11 
ETHICS 
11 
DATA HANDLING AND RECORD KEEPING 
11 
FINANCING AND INSURANCE 
12 
REFERENCES 
12 
 
 
 

TAP-DEX: Transversus Abdominis Plane Blocks with and without Dexamethasone: A Randomized 
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Title: Transversus Abdominis Plane Blocks with and wthout Dexamethasone: A Randomized 
Clinical Trial in Minimally Invasive Colorectal Surgery 
Investigators:   
 
Dr. D. Nathan Ginther (Principal Investigator, physician in charge of trial-site medical decisions) 
Department of Surgery  
University of Saskatchewan 
Rm 151 Ellis Hall 
103 Hospital Drive, Saskatoon, SK 
S7N 0W8 Canada 
 
Dr. Dilip Gill (Co-investigator) 
Staff Physician, Department of Surgery, University of Saskatchewan 
 
Dr. Henry Bi (Co-investigator) 
Staff Physician, Department of Anesthesiology, University of Saskatchewan 
 
Dr. Zarrukh Baig 
Resident, Department of Surgery, University of Saskatchewan 
 
Dr. Nawaf Abu-Omar, MD 
 
 
 
 
Resident, Department of Surgery, University of Saskatchewan  
 
 
Sponsor: 
 
Dr. D. Nathan Ginther 
 
Trial site: 
 
Royal University Hospital 
103 Hospital Drive, Saskatoon, SK 
S7N 0W8 Canada 
Ph 306-655-1183 
 
St. Paul’s Hospital 
1702 20th St. West, Saskatoon, SK 
S7M 0Z9 Canada 
Ph 306-655-5000 
 
Additional Canadian trial sites may be added in future.  

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Background Information 
 
Minimally invasive colorectal surgery has dramatically improved postoperative outcomes, resulting in 
significantly shorter length of stay, pain, and overall cost. 1 Despite the advances in multimodal 
analgesia and enhanced-recovery pathways, the optimal strategy for perioperative analgesia has not yet 
been defined, and there may be a role for expanded use of regional anesthesia in minimally invasive 
surgery. 
 
Regional anesthesia, specifically the transversus abdominis plane (TAP) block, has been shown to 
reduce postoperative pain and opioid requirements even in the context of minimally invasive surgery. 
2,3,4,5,6 Surgeon-performed, laparoscopically placed TAP blocks are equivalent, or perhaps superior, to 
ultrasound-guided TAP blocks7,8. Long-acting local anesthetics, specifically liposomal bupivacaine, 
have been shown to prolong the effect of TAP blocks over non-liposomal bupivacaine910, and has also 
suggested a reduced length of stay and less overall cost, despite the high cost of the formulation.11 These 
findings suggest improved outcomes can be expected if a longer block can be achieved.  
 
Liposomal bupivacaine is not currently available in Canada and is very costly. In addition, recent 
evidence has called into question the efficacy of liposomal bupivacaine, specifically regarding rebound 
pain. Rebound pain can occur with any type of regional anesthesia, but intravenous corticosteroids seem 
to mitigate this problem.12  
 
We hypothesize that addition of dexamethasone to bupivacaine can prolong the duration of sensory 
block to be similar to that achieved with liposomal bupivacaine, but at a much lower cost. 
Dexamethasone was chosen due to its current widespread use in regional anesthesia, long biological 
half-life (36-54 hours), low cost, availability, and absence of any evidence of harm with single-dose use.  
 
Regional anesthetic supplemented with perineural dexamethasone, a potent corticosteroid, has shown 
improved efficacy and prolonged duration of anesthetic in a variety of regional anesthetic techniques as 
well as in spinal anesthesia.13,14 ,15  The duration of sensory block can be nearly doubled when 
dexamethasone is combined with long-acting local anesthetics for perineural anesthesia in brachial 
plexus and interscalene blocks. 1617  
 
Dexamethasone in combination with local anesthetic has been the subject of several meta-analyses and 
systemic reviews, which universally suggest a synergistic effect on duration of sensory block. 181920. It 
remains unclear whether the effect is greater with systemic or perineural administration, with moderate 
quality evidence suggesting a stronger effect from perineural administration.21 
 
The adjunctive analgesic effect of dexamethasone is thought to be mediated by attenuating the release of 
inflammatory mediators, reducing ectopic neuronal discharge, and inhibiting potassium channel-
mediated discharge of nociceptive C-fibres. Corticosteroids possess potent anti-inflammatory effects. 
Dexamethasone as an adjunct to local anesthetic is thought to work through reduction in inflammatory 
mediators, less ectopic neuronal discharge, and reduced potassium channel-mediated transmission in 
nociceptive C-fibres222324. Local vasoconstriction may also play a role.25 However, the exact mechanism 
by which dexamethasone reduces pain remains unknown. It also remains unclear whether the proven 
analgesic benefits are due to local (perineural) or systemic effects. While controversial, the burden of 
evidence points to increased effect from perineural administration. 26  

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Local (incisional) subcutaneous injection of dexamethasone may also provide analgesic benefit. In a 
placebo-controlled randomized trial assessing subcutaneous injection of 16mg dexamethasone into 
cesearean-section incisions against intravenous administration of the same dose and a placebo group, 
local injection was found to have significantly less postoperative pain than the other two groups. In 
addition, the local injection group had less postoperative nausea than the placebo group, suggesting a 
protective effect against postoperative nausea and vomiting.27 
 
There are no known safety concerns about single-dose perioperative dexamethasone, and no reports of 
harm could be identified with its use as an adjunct to regional anesthesia. Three studies have reported on 
potential harms with administration for brachial plexus block; no prolonged nerve palsies were 
identified in 407 patients.282930 One study reported a minor, but clinically insignificant, rise in blood 
glucose concentration. A 2018 Cochrane review examined adverse side effects of dexamethasone in 
surgical patients and concluded that there was no effect on surgical site infection, unclear effects on 
wound healing, and a transient (<12 hour) mild rise in blood glucose concentration of uncertain 
significance.  The effect was similar for low (4-5mg), moderate (8-10mg) or high (12-20mg) doses31. 
Notably, this review assessed effects of intravenous dexamethasone, which would be expected to have 
more pronounced systemic effect than perineural injection.  
 
Although widely used in clinical practice, adjunctive application for regional anesthesia is an off-label 
use. Dexamethasone has not been approved for perineural administration by Health Canada, the United 
States Food and Drug Administration, nor any other regulatory body.  
Trial Objectives and Purpose 
 
The objective of this trial is to investigate the effect of adjuvant dexamethasone in combination with 
bupivacaine to increase the depth and duration of sensory block in laparoscopically placed transversus-
abdominis plane (TAP) blocks. The primary outcome will be total opioid consumption, in hydromorphone 
equivalents, in the first 48 hours after surgery. Secondary outcomes will be length of stay in the post-
anesthetic care unit (PACU) and length of stay in hospital. The results of this study will serve as a proof-
of-concept and will guide future research exploring adjuvant dexamethasone use in TAP blocks, 
specifically optimal dosing and ultimately a head-to-head comparison with systemic dexamethasone.  
 
The results of this study will be of benefit to patients presenting for colorectal surgery, and more likely 
any type of abdominal surgery. Further research and refinement of regional anesthesia protocols adds to 
the armamentarium of anesthetic modalities available to anesthesiologists and surgeons and may offer a 
strategy for improved patient care.  
Trial Design  
 
This study will be carried out as a prospective, randomized, single-blinded clinical trial. 
 
The intervention group will receive intraoperative laparoscopically assisted, surgeon-placed TAP blocks 
using 1mL/kg of 0.25% bupivacaine with epinephrine 1:200,000 combined with 16mg dexamethasone 
divided into 4 aliquots to be placed at two locations per side along the anterior axillary line between the 

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costal margin and the iliac crest. The control group will have TAP blocks with the same dose of 
bupivacaine without dexamethasone. The blocks will be performed at the conclusion of surgery. 
Postoperatively, all patients will be provided with patient-controlled analgesia (PCA) with institutional 
standardized orders.  
 
Intravenous dexamethasone will not be given for prevention of postoperative nausea and vomiting 
(PONV); prophylaxis of postoperative nausea and vomiting will be at the discretion of the 
anesthesiologist, but can include any of ondansetron, haloperidol, or dimenhydrinate. If PONV occurs 
and is refractory to non-corticosteroid treatment, dexamethasone may be given for treatment but would 
result in exclusion from the trial. General anesthetic technique will be at the discretion of the 
anesthesiologist, but the following adjunct anesthetic drugs will not be permitted, due to independent 
effects on postoperative pain: dexmedetomidine, lidocaine, and ketamine.323334 These adjuncts are 
occasionally used in anesthetic protocols, but their exclusion will not affect the quality of the anesthetic 
provided, and their use is not considered standard of care. All patients will be provided with a 
standardized hydromorphone-based patient-controlled analgesia (PCA) for a minimum of 48 hours 
postoperatively.  
 
The primary outcome will be total opioid consumption, in hydromorphone equivalents, in the first 48 
hours after surgery. Secondary outcomes will be length of stay in the post-anesthetic care unit (PACU), 
length of stay in hospital, and total opioids administered in the PACU.  
 
A computer-generated random number table will be used to randomize patients to receive either 
bupivacaine alone (n=60) or bupivacaine plus dexamethasone (n=60). Allocation will be performed in a 
1:1 ratio. Group allocation will be concealed via a centralized third-party research assistant. Group 
allocation will be blinded to study participants, study investigators, post-anesthetic care unit (PACU) 
nursing staff, and surgical ward nursing staff. The attending surgeon and attending anesthesiologist on the 
day of surgery will not be blinded to the intervention, however, they will be asked to conceal the anesthetic 
modality from the PACU staff and ward nurses. The intervention will be charted in the Operating Room 
record, but not on the anesthetic record. PACU nurses commonly review the anesthetic record, whereby 
they would discover the intervention.  
 
A blinded, centralized, third-party research assistant or study investigators will carry out data collection. 
Postoperative opioid consumption will be quantified through chart review as well as assessment of patient-
controlled analgesia (PCA) usage at 24 and 48 hours following the operation. Recording the doses of 
opioids administered in the medication administration record (MAR) is standard practice by PACU 
nursing staff at the study institution. PCA pumps automatically document cumulative opioids administered 
and can easily be checked at the bedside, as well as being recorded in the MAR. Length of stay in hospital 
is readily available from the chart.  
 
Followup for primary and secondary outcomes will be limited to 48 hours postoperatively, and assessment 
of infiltration sites for complications will be performed at 6 weeks postoperatively.  
 
 
Stopping Criteria 
 

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Interim analysis will be performed after 50% enrolment. If either arm is found to be superior, the trial will 
be discontinued. If any adverse events are identified in either arm, a safety review will be performed. 
Should a significant safety concern be identified, the trial will be discontinued.  
 
Pharmacokinetics and Pharmacodynamics– Bupivicaine35 
 
Pharmacodynamics and Pharmacokinetics  
Onset of action: Anesthesia (route and dose dependent): 
Epidural: Up to 17 minutes to spread to T6 dermatome (Scott 1980). 
Infiltration: Fast (Barash 2009); Dental injection: 2 to 10 minutes. 
Spinal: Within 1 minute; maximum dermatome level achieved within 15 minutes in most cases. 
Duration (route and dose dependent): 
Infiltration: 2 to 8 hours (Barash 2009); Dental injection: Up to 7 hours. 
Distribution: Vd: Infants: 3.9 ± 2 L/kg; Children: 2.7 ± 0.2 L/kg. 
Protein binding: 84% to 95%. 
Metabolism: Hepatic; forms metabolite (pipecoloxylidine [PPX]). 
Half-life elimination (age dependent): Implant: 19 hours; Injection: Neonates: 8.1 hours; Adults: 2.7 
hours; Subacromial injection: 16.4 to 26.1 hours. 
Time to peak, plasma: Caudal, epidural, or peripheral nerve block: 30 to 45 minutes; Implant: Median: 3 
hours (range: 1.5 to 24 hours); Subacromial injection: Median: ~6 to 8 hours (range: 1 to ~27 
hours). 
Excretion: Urine (~6% unchanged). 
Clearance: Infants: 7.1 ± 3.2 mL/kg/minute; Children: 10 ± 0.7 mL/kg/minute. 
 
Pharmacokinetics and Pharmacodynamics– Dexamethasone36 
 
Onset of action: IV: Rapid. 
Immune thrombocytopenia: Oral: Initial response: 2 to 14 days; Peak response: 4 to 28 days 
(Neunert 2011). 
Duration: IV: Short. 
Absorption: Oral: 61% to 86% (Czock 2005). 
Metabolism: Hepatic. 
Half-life elimination: 
Adults: Oral: 4 ± 0.9 hours (Czock 2005); IV: ~1 to 5 hours (Hochhaus 2001; Miyabo 1981; 
Rohdewald 1987; Tóth 1999). 
Time to peak, serum: Oral: 1 to 2 hours (Czock 2005); IM: ~30 to 120 minutes (Egerman 1997; 
Hochhaus 2001); IV: 5 to 10 minutes (free dexamethasone) (Miyabo 1981; Rohdewald 1987). 
Excretion: Urine (~10%) (Duggan 1975; Miyabo 1981). 
 
Selection and withdrawal of subjects 
 
We intend to enroll a sample size of 120 patients based on an alpha set at 0.05, power set at 0.08, and the 
effect size set at 0.8. 
 
Inclusion criteria are: age > 18, ASA class I-III patients scheduled for elective or urgent inpatient 
laparoscopic/laparoscopic assisted colorectal surgery.  

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Exclusion criteria are: emergency surgery, open surgery, contraindications to laparoscopic surgery (ie. 
adhesions, inability to tolerate pneumoperitoneum), ASA class  4, age < 18, pregnant or breastfeeding 
women, significant cardiorespiratory/hepatic/renal disease, allergy to any study drugs, inability to consent, 
inability to respond to pain assessments, inability to use the patient-controlled analgesia device (PCA), 
preoperative chronic opioid use.  
 
Potential participants will be identified by their attending surgeon during their initial clinic surgical 
consultation. This typically occurs several weeks in advance of their scheduled surgical procedure. 
Information detailing the study, as well as contact information of the research team will be made 
available to patients at this time should they have any questions. After having had a chance to review the 
study information provided to them by their surgeon, prospective patients will be assessed by study staff 
(attending surgeon or designate such as a general surgery resident) and asked to sign a consent if they 
agree to participate and meet the inclusion criteria. The consent will be taken on the day of surgery. 
 
Participants who are unable to personally provide informed consent will be excluded from the study. No 
third party will be allowed to consent on the participants behalf. Capacity will be assessed by the study 
staff or designate obtaining consent. All patients participating must be assessed to determine that they 
fully understand the protocol, risks, and benefits of participating in the study. 
 
Subjects will be free to withdraw voluntarily from the study at any point. The process for withdrawal 
can be initiated by the participant at any time by informing any of the study staff of the decision to 
withdraw. No explanation for withdrawal will be sought. If this occurs prior to randomization, no patient 
information will be collected for study purposes, and the patient will still be eligible to undergo surgery 
as planned without compromise to care. If withdrawal occurs during data collection, data collected on 
the subject will be destroyed, and they will continue receiving post-operative care as per standards. 
Either of the attending anesthesiologist or attending surgeon caring for the patient on the day of surgery 
has the ultimate discretion as to whether a patient is included or excluded from the study. If the 
attending surgeon or anesthesiologist deems the patient unfit to participate in the study, this will be 
communicated to the study coordinator, and the patient will be withdrawn. All adverse events and 
protocol deviations will be reported to the study coordinator, study investigators, and appropriate 
Research Ethics Board. Subjects who are withdrawn from the study due to the occurrence of an adverse 
event will be followed up by one of the study’s physician investigators while in hospital. If the adverse 
event is believed to have been related to the study drug, a detailed note will be made in the patient’s 
medical record and passed on to future care providers. Subjects withdrawn from the study due to an 
adverse event will not be replaced. Any adverse events will result in unblinding by notification of the 
principle investigator. 
 
Treatment of subjects 
All study subjects will be assessed by an anesthesiologist in the Preoperative Assessment Clinic (PAC) 
prior to their scheduled procedure date. At this time, subjects will undergo a comprehensive medical 
assessment, including a review of their current prescription medications. At the discretion of the reviewing 

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anesthesiologist, subjects will be counselled regarding which medications may be safely continued or held 
prior to their procedure.  
All subjects will receive standard anesthetic, analgesic, amnestic, and anxiolytic medications under the 
care of a qualified anesthesiologist. Vasopressors will be used when appropriate as part of standard 
practice in the operating room. The choice of anesthetic technique will be at the discretion of the treating 
anesthesiologist, however the anesthetic adjuncts of dexmedetomidine, lidocaine, and ketamine will not 
be permitted due to significant potential for confounding due to independent effect on postoperative pain. 
All patients will be premedicated with acetaminophen 975 mg on the day of their scheduled procedure in 
the Same Day Surgery (SDS) unit prior to arriving in the operating room. Once in the operating room, 
standard monitors including noninvasive blood pressure, electrocardiography, pulse oximetry, and 
capnography will be applied as per Canadian Anesthesiologists’ Society (CAS) guidelines. Neither group 
will receive systemic dexamethasone for PONV prophylaxis; alternative PONV prophylaxis may include 
ondansetron or haloperidol, to be given at the discretion of the treating anesthesiologist.  
Both groups will receive surgeon-placed, laparoscopically visualized transversus abdominus plane (TAP) 
block at the end of the surgical procedure prior to emergence from anesthesia as an analgesic adjunct using 
1mL/kg of 0.25% bupivacaine with epinephrine 1:200,000 divided in four aliquots to be placed at two 
locations per side along the anterior axillary line between the costal margin and the iliac crest. The 
intervention group will have dexamethasone 16mg combined with the bupivacaine / epinephrine, with 
4mg to be injected at each TAP site, for a total of 8mg dexamethasone per side. The study drug will be 
provided from wardstock available in the operating room, and will be prepared by nursing staff as per 
standard perioperative nursing practice.  The control group will have TAP blocks with the same dose of 
bupivacaine without dexamethasone. The bupivacaine / lidocaine solution will be sourced from the 
hospital pharmacy, and is purchased from Sandoz Canada 
Currently, the colorectal surgeons based at Royal University Hospital are experienced with performance 
of TAP blocks and have been performing them for several years. If there is interest from other general 
surgeons in participating in the trial, in-person training will be provided to that surgeon by one of the 
experience surgeons to ensure standardization of the technique. 
Following surgery, patients will be extubated fully awake in the operating room and transferred to the 
PACU. In PACU, both groups will have access to nurse-administered multimodal analgesia including 
rescue hydromorphone for postoperative pain relief. Standard antiemetics will be available as well. Upon 
discharge from PACU, hydromorphone-based patient-controlled analgesia (PCA) will be initiated and 
continued for a minimum of 48 hours postoperatively. Morphine-based PCA can be substituted if there is 
a contraindication to hydromorphone. Both groups will receive acetaminophen 975mg PO Q6H scheduled 
for 48 hours then PRN. 
Surgical ward nurses will be not informed that the patient is involved in the study, as participation is not 
relevant to postoperative care, which will be administered as per usual. The study institution maintains a 
standardized colorectal-surgery postoperative pathway directing advancement of diet, intravenous 
maintenance fluids, deep-vein thrombosis prophylaxis, and urinary catheter management. 

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Assessment of efficacy 
The primary efficacy outcome of this study will be total opioid consumption, in hydromorphone 
equivalents, at 24 and 48 hours postoperatively. Secondary outcomes will be length of stay in the post-
anesthetic care unit (PACU), length of stay in hospital, and total opioids administered in the PACU. 
Assessment of safety 
 
Following surgery, adequacy of analgesia will be closely monitored, and inadequate analgesia will be 
treated as per standard protocol in the postanesthetic care unit (PACU). Physical examination of the 
TAP block injection sites will be performed daily and at the 6 week postoperative follow up visit. 
Diabetic patients will have blood glucose monitoring as per standard protocol, and all patients will have 
serial vital signs four times daily. Clinical assessment for severe postoperative nausea and vomiting 
(PONV) will be performed as per nursing protocol, and by the attending anesthesiologist on daily round. 
Any serious adverse events will be followed closely until resolution, with frequency of follow up to be 
determined by clinical judgement. Education to ward nurses will be provided on identification and 
reporting of adverse events. Adverse events will be recorded in the data collection tool. All serious 
adverse events will be reported to the Research Ethics Board and Health Canada as per the University of 
Saskatchewan Serious Adverse Events Reporting Policy and the Health Canada Guidance for Clinical 
Trial Sponsors document. Any serious unexpected adverse drug events will be reported to Health 
Canada. During the course of the trial, the sponsor will inform Health Canada of any serious unexpected 
adverse drug reaction (SUARD) as follows: 
o (a) if it is neither fatal nor life threatening, within 15 days after becoming aware of 
the information; and 
o (b) if it is fatal or life threatening, within seven days after becoming aware of the 
information. 
 
Definitions of reactions are as follows: 
 
Serious Adverse Drug Reaction: An adverse drug reaction that requires in-patient hospitalization or 
prolongation of existing hospitalization, that causes congenital malformation, that results in persistent or 
significant disability or incapacity, that is life threatening or that results in death. 
 
Serious Unexpected Adverse Drug Reaction (SUADR): A serious adverse drug reaction that is not 
identified in nature, severity or frequency in the risk information set out in the investigator's brochure or 
on the label of the drug. 
 
Statistics 
 
Primary Outcome:  
 
Total opioid consumption at 24 and 48 hours will be gathered from the PCA record and Medication 
Administration Record (MAR).  Intention to treat analysis will be performed. Parametric data will be 
analyzed with the students t-test for statistical significance.  
 

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Secondary Outcome: Opioid consumption in the PACU will be reported in hydromorphone equivalents 
and compared with chi square test. Length of stay in PACU and length of stay in hospital will be reported 
as a mean +/- standard deviation (SD), along with confidence intervals and compared with chi square test. 
 
Interim Analysis 
 
Interim analysis for primary and secondary outcomes, as well as safety parameters, will be performed 
upon completion of 50% of the total recruitment. If statistically significant superiority of either arm is 
identified, the trial will be terminated.  
Direct access to source data / documents 
 
The Investigator acknowledges that some authorities have a duty to monitor the study records to make 
sure all the information is correct. The study records may be inspected in the presence of the investigator 
or his qualified designate by representatives of Health Canada or the University of Saskatchewan 
Biomedical Research Ethics Board for quality assurance and/or regulatory purposes.  
Quality Control and Quality Assurance Procedures 
 
Patients will be monitored intraoperatively by a qualified staff anesthesiologist. Following surgery, 
patients will be extubated fully awake in the operating room and transferred to the PACU with 
supplemental oxygen. In PACU patients will be monitored by dedicated nursing staff and will have 
access to nurse-administered analgesia. Standard antiemetics will be available as well, and 
dexamethasone can be given systemically as a rescue antiemetic. If this occurs, the patient will be 
excluded from the study.  Following discharge from PACU, patients will be monitored on the ward by 
nursing staff and postoperative care will be administered as per usual protocol.  
Ethics 
 
The Investigator will ensure that this study is conducted in full compliance with the principles of the 
Declaration of Helsinki and with the laws and regulations in Canada. This clinical study will be 
implemented and reported in accordance with the ICH Harmonized Tripartite Guidelines for Good 
Clinical Practice.  
This study (including protocol and proposed consent form) has been submitted to the University of 
Saskatchewan Biomedical Research Ethics Board. Eligible subjects will only be included in the study 
after providing written BREB-approved consent.  
Data handling and record keeping 
 
All information collected on the data collection form will be de-identified and no direct personal identifiers 
will be recorded.  All measures will be taken to maintain confidentiality on collected data; however, there 
is a chance of unintentional release of information connecting the subject with the study.  A list connecting 

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the subject's name to the subject study number listed on the data collection form will be stored in a 
password-protected computed kept in the locked office of the principal investigator, located at Royal 
University Hospital, Saskatoon.  Access to this list will be limited to study staff, and it will be destroyed 
upon study completion through the confidential paper shredding services of the Royal University Hospital. 
 
Data will be stored for 25 years, as per the Health Canada requirements.  The Investigator is responsible 
to archive the documents/data for the required period of time. 
Financing  
 
This study has received funding of $10,000 from the Department of Surgery, University of 
Saskatchewan.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
References 
 
 
1 Noel, J. Kay, et al. "Minimally invasive colorectal resection outcomes: short-term comparison with open procedures." Journal of the 
American College of Surgeons 204.2 (2007): 291-307 
 
2 Park JS, Choi GS, Kwak KH, et al. Effect of local wound infiltration and transversus abdominis plane block on morphine use after 
laparoscopic colectomy: a nonrandomized, single-blind prospective study. J Surg Res. 2015;195:61–66. 
 
3 Keller DS, Ermlich BO, Schiltz N, et al. The effect of transversus abdominis plane blocks on postoperative pain in laparoscopic colorectal 
surgery: a prospective, randomized, double-blind trial. Dis Colon Rectum. 2014;57:1290–1297. 
 

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4 Ris F, Findlay JM, Hompes R, et al. Addition of transversus abdominis plane block to patient controlled analgesia for laparoscopic high 
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2014;96:579–585. 
 
5 Tikuisis R, Miliauskas P, Lukoseviciene V, et al. Transversus abdominis plane block for postoperative pain relief after hand-assisted 
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6 Rajanbabu, Anupama, et al. "Efficacy of laparoscopic-guided transversus abdominis plane block for patients undergoing robotic-assisted 
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in minimally invasive colorectal surgery." Diseases of the Colon & Rectum 62.2 (2019): 203-210. 
 
8 Wong, Daniel J., et al. "Surgeon-delivered laparoscopic transversus abdominis plane blocks are non-inferior to anesthesia-delivered 
ultrasound-guided transversus abdominis plane blocks: a blinded, randomized non-inferiority trial." Surgical endoscopy 34.7 (2020): 3011-
3019. 
 
9 Hutchins, J. L., et al. "Ultrasound‐guided subcostal transversus abdominis plane blocks with liposomal bupivacaine vs. non‐liposomal 
bupivacaine for postoperative pain control after laparoscopic hand‐assisted donor nephrectomy: a prospective randomised observer‐blinded 
study." Anaesthesia 71.8 (2016): 930-937. 
 
10 Hutchins J, Delaney D, Vogel RI, et al. Ultrasound guided subcostal transversus abdominis plane (TAP) infiltra-tion with liposomal 
bupivacaine for patients undergoing robotic assisted hysterectomy: a prospective randomized controlled study. Gynecol Oncol. 
2015;138:609–613.16. 7 
 
11 Stokes, Audrey L., et al. "Liposomal bupivacaine use in transversus abdominis plane blocks reduces pain and postoperative intravenous 
opioid requirement after colorectal surgery." Diseases of the Colon & Rectum 60.2 (2017): 170-177. 
 
12 Barry, Garrett S., et al. "Factors associated with rebound pain after peripheral nerve block for ambulatory surgery." British Journal of 
Anaesthesia 126.4 (2021): 862-871. 
 
13 Heesen M, Klimek M, Imberger G, Hoeks SE, Rossaint R, Straube S. Co-administration of dexamethasone with peripheral nerve block: 
intravenous vs perineural application: systematic review, meta-analysis, meta-regression and trial-sequential analysis. Br J Anaesth. 
2018;120:212–227. 
 
14 Pehora, Carolyne, et al. "Dexamethasone as an adjuvant to peripheral nerve block." Cochrane Database of Systematic Reviews 11 
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TAP-DEX: Transversus Abdominis Plane Blocks with and without Dexamethasone: A Randomized 
Clinical Trial in Minimally Invasive Colorectal Surgery 
 
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35 PRODUCT MONOGRAPH Bupivacaine Hydrochloride Injection, USP, Baxter CorporationMississauga, Ontario, May 2019 
36Dexamethasone (systemic): Drug information. Lexicomp, Inc., 2021