Effect of Unilateral Ultrasound-Guided Subcostal Transversus Abdominis Plane Block in Patients Undergoing Laparoscopic Sleeve Gastrectomy
Phase: PHASE4
Conditions: Laparoscopic Sleeve Gastrectomy, Subcostal Transversus Abdominis Plane Block
Sponsor: Icahn School of Medicine at Mount Sinai

Effect of Unilateral Ultrasound-Guided Subcostal Transversus Abdominis Plane Block 
in Patients Undergoing Laparoscopic Sleeve Gastrectomy
PI: Christina Jeng, MD
NCT03856788
Document Date: Sept 9, 2019

Title: Effect of Unilateral Ultrasound-Guided Subcostal Transversus Abdominis Plane Block in
Patients Undergoing Laparoscopic Sleeve Gastrectomy
Researchers: Ying (Amy) Ye, Jordan Wicker, Garrett Burnett, Chang Park, Mike Anderson,
Christina Jeng
Hypothesis: Laparoscopic sleeve gastrectomy patients who receive unilateral
ultrasound-guided subcostal transversus abdominis plane (TAP) block will have decreased
opioid consumption
Objectives
Primary Objective:
Compare amount of intravenous (IV) opioid consumption within 24-hour period amongst
laparoscopic sleeve gastrectomy patients who receive the unilateral ultrasound-guided
subcostal TAP block with bupivacaine to those who receive the block with only sterile saline.
Secondary Objectives:
a.
Amount of intraoperative IV opioid consumption
b.
Amount of post-operative IV opioid consumption
c.
Severity of pain at rest using an 11-point numeric pain score Likert scale at 1, 6, 12 and
24-hour marks postoperatively
d.
Time to breakthrough pain after surgery
e.
Area of pain after surgery
f.
Presence of postoperative nausea (yes/no) at 1, 6, 12 and 24-hour marks
postoperatively
g.
Time to ambulation after surgery
h.
Analgesia satisfaction score at end of hospital stay
i.
Hospital length of stay
Background
Over the last decade, there has been an increasing number of people undergoing bariatric
surgeries, including laparoscopic sleeve gastrectomy. While these surgeries are performed
laparoscopically, many patients still have considerable amounts of pain. The Enhanced
Recovery After Surgery (ERAS) Society recommends a multimodal analgesic strategy for
managing pain for laparoscopic sleeve gastrectomy patients so as to improve patient comfort,
and minimize opioid consumption, thereby also reducing the complications associated with
narcotic use, such as nausea, respiratory depression, and reduced bowel motility. However,
there is currently no consensus as to the best pain management strategy for these patients. 1
Several different approaches to effective analgesic management for bariatric patients have been
proposed. Studies comparing patient-controlled epidural to standard IV patient-controlled (PCA)
opioid analgesia have been promising 2,3. However, epidural placement in morbidly obese

individuals may be technically challenging. Furthermore, complications from epidural analgesia
including hypotension, dural puncture, and spinal infection or injury can be catastrophic, limiting
routine placement in patients undergoing bariatric surgery.  Rectus sheath blocks have shown
potential to reduce postoperative pain in patients undergoing upper abdominal surgeries, but no
studies have evaluated its specific effects in laparoscopic bariatric surgery 4. Local anesthetic
infiltration into trocar sites have also been suggested, but so far has not been shown to reduce
postoperative pain 5.
Recently, transversus abdominis plane (TAP) blocks has garnered attention due to the relative
ease of placement and low risk for complications. 6 The goal of the TAP block is to deposit local
anesthesia in the plane between the internal oblique and transversus abdominis muscles so as
to anesthetize the anterior rami of the T7-L1 7,8. Studies have found that the classic TAP block,
in which the needle enters at the lumbar triangle of Petit, provided analgesia only up to T10,
making this block more suitable for lower abdominal surgeries 9,10, and less ideal for
laparoscopic sleeve gastrectomy. Recent studies are now focusing on modified TAP blocks as a
means to provide adequate perioperative analgesia for these patients 11,12. Ibrahim et al.
compared the effects of bilateral oblique subcostal TAP blocks, local anesthetic infiltration alone
at port sites, and no block or infiltration; compared to the other two groups, patients receiving
bilateral oblique subcostal TAP blocks had significantly lower pain scores postoperatively for
patients undergoing laparoscopic sleeve gastrectomy surgeries 12. Despite these positive
results, oblique subcostal TAP blocks are harder to perform than the standard subcostal TAP
block, requiring a longer ultrasound needle and larger volumes of local anesthetic 13. Ari et al.
also did not find any difference in pain scores between patients receiving bilateral subcostal TAP
blocks to those receiving both bilateral subcostal and posterior TAP blocks 11.
Adequate perioperative analgesia is immensely important for bariatric patients, yet there is still
no current consensus on optimal pain control. Regional anesthesia techniques are showing
promising results. We propose that a unilateral subcostal TAP block, which is easy to perform
with minimal risks to patients, may help in minimizing pain and nausea for patients undergoing
laparoscopic sleeve gastrectomy.
Eligibility Criteria
Inclusion Criteria:
●
Adults 18-80 years old
●
Candidate for general anesthesia
●
Undergoing laparoscopic sleeve gastrectomy
●
Patients of participating surgeons
Exclusion Criteria:
●
Prior bariatric surgery of any kind

●
Previous abdominoplasty
●
Allergy or intolerance to one of the study medications
●
ASA > 4
●
Chronic opioid use (taking opioids for longer than 3 months or daily oral morphine
equivalent of >5mg/day for one month)
●
History of alcohol/drug abuse
●
History of hepatic or renal insufficiency
●
Patient refusal
●
Patients who do not speak English
Other Aspects that Could Increase Subjects’ Vulnerability
Patients undergoing surgical procedures often have anxiety with surgery. Anesthesiologists will
treat this perioperatively with medications and reassurance.
Safeguards to Protect Subjects’ Rights and Welfare
Perioperative anxiety will be treated by reassurance and medications as per standard of care.
Regardless of participation in the study, patients will undergo their scheduled surgery. Patients
will be provided contact information on the consent form in case of any rising concerns or
suggestions. Researches will ensure that protected health information be kept safe and
confidential.
Duration of Participation
Individual participation in this study will conclude following discharge from the hospital after
laparoscopic gastrectomy surgery. Duration of participation will depend on the length of
hospitalization. Typical duration of stay for this type of surgery is usually 1--3 days.
Procedures for Subjects to Request Withdrawal
Patients may withdraw from the study at any point in the investigation. Patients will be provided
with contact information and must withdraw in writing. Should this decision be made prior to the
procedure, the patient will undergo the surgery as per current standard of care; they will not be
included in the experimental protocol. If they choose to withdraw following surgery,
post-operative data collection will stop. Regardless of decision to withdraw from the study,
subjects will receive current standard of care. Collected PHI will be destroyed at the time of
withdrawal.
Procedures for Investigators to Withdraw Subjects
The patient will be informed if they need to be withdrawn from the study. Should this decision be
made prior to the procedure, the patient will undergo the surgery as per current standard of
care; they will not be included in the experimental protocol. If this is decided following surgery,
post-operative data collection will stop. Regardless, subjects will receive current standard of
care. Collected PHI will be destroyed at the time of withdrawal.
How Participants will be Identified

Patients scheduled for laparoscopic gastrectomy procedure with Dr. Scott Nguyen and Dr.
Edwards Chin will be identified at at their preoperative surgical visit. The surgery team will
discuss the study and provide written information/consent for the patient to review.
Approximately 1 week prior to the surgery, a member of the research team will call the patient to
discuss the study further and address any additional questions or concerns. They will also
discuss the study in detail, confirm understanding, and review the consent form with the patient.
If the patient agrees to the procedure, they will sign the consent on the day of surgery in the
GP2 preoperative waiting area or in the GP3 holding area.
How Research will be Introduced to Participants
At the pre-operative surgical visit, eligible patients will be introduced to the research by the
surgical team. Approximately 1 week prior to the surgery, a member of the research team will
call the patient to discuss the study further and address any additional questions or concerns.
They will also discuss the study in detail, confirm understanding, and review the consent form
with the patient.
How Participants will be Screened
At the pre-operative surgical clinic visit, patients will be screened for eligibility based on stated
inclusion and exclusion criteria. The patient will be screened again during the follow-up phone
call made by a member of the research team approximately one week before the scheduled
surgery.
Risk to Subjects
Complications for TAP blocks and its variants, including the subcostal TAP block, are rare.
Incorrect needle advancement through the peritoneum may result in injuries to organs such as
to the stomach or bowel perforation. Other complications include hematoma, infection and local
anesthetic toxicity.
Description of Procedures Taken to Lessen the Probability or Magnitude of Risks
To minimize risk, ultrasound guidance will be used for all subcostal TAP blocks. Slow injection of
local anesthetic with intermittent aspiration will help reduce the risk of inadvertent vascular
injection of local anesthetic. Patients will be monitored in accordance to the standards of the
American Society of Anesthesiologists during the entirety of the surgery. Following the surgery,
they will be monitored in the post-anesthesia care unit.
Provisions for Research Related Harm/Injury
Patients will be provided with a phone number to call for any concerns related to surgery,
anesthesia or the study. Should any complication requiring medical attention arise, patients will
be instructed to return to the hospital. Subjects injured as a result of the this study will be
treated, with the costs billed to them and/or their insurance company. Patients will not be
compensated for research related injury.
Expected Direct Benefit to Subjects

Patients who receive a subcostal TAP block may experience less postoperative pain. This may
possibly lead to lower opioid consumption, and thereby, result in fewer side effects related to
opioid consumption.
Benefit to Society
Subcostal TAP blocks may be incorporated into an Enhanced Recovery after Surgery protocol
for laparoscopic gastrectomies should this study show decreased opioid consumption and
improved outcomes with this truncal nerve block.
Provisions to Protect the Privacy Interests of Subjects
De-identified data will be stored on secure, password-protected servers maintained by the
Mount Sinai Information Technology department. Access to the data will only be available to
Mount Sinai IT administrators and the study investigators. A one-way hash ID will be generated
for each record once the de-identified data set is released for analysis. Only the study
investigators with access to the full data set will be able to match the hash ID to the original
record. All investigators must have completed the HIPAA training pertaining to PHI
confidentiality.
Economic Impact on Subjects
There is no additional cost to subjects for participating in this study. There is no compensation
for participants.
Description of Study Design
Patients who are eligible for this subject will be invited to participate. Written informed consent
will be obtained from eligible volunteers for this study.
This study will be a double-blinded randomized control trial. Patients will be randomized into one
of two groups. Patients in Group 1 will undergo general anesthesia with a post-induction,
post-intubation, pre-procedural subcostal TAP block with 40 mL 0.25% bupivacaine on the
ipsilateral side as the extraction site. Patients in Group 2 will undergo general anesthesia with a
post-induction, post-intubation, pre-procedural subcostal TAP block with 40 mL sterile normal
saline on the ipsilateral side as the extraction site. Investigators will be blinded to the
randomization of these patients. Following performance of these blocks, patients will receive
standard care for the surgery as well as during the postoperative recovery period. Data will be
obtained from the EPIC electronic medical record, and from the anesthesia computer record.
Patients will be asked postoperatively to assess items such as their nausea and pain scores.
Patients will also be contacted by phone within 1-2 days of discharge to obtain analgesic
satisfaction scores. This data will be collected on the Redcap server.
Description of Procedures being Performed
Group allocation and instructions on preparing the injectate solution for the subcostal TAP block
will be included in a sealed envelope. On the day of the surgery, the group allocation will be

revealed to an anesthesiologist not involved with the research study. The anesthesiologist will
prepare the solution to be used for the subcostal TAP block.
Standard ASA monitors will be applied to all patients. A preoperative intravenous line will be
placed. Patients will undergo standard induction with IV propofol, fentanyl and rocuronium. All
study patients will receive 1.5mcg/kg of IV fentanyl on induction. Following induction, a
subcostal TAP block will be performed on the ipsilateral site as the extraction site. Patients will
be positioned in the supine position. A linear ultrasound probe will be parallel to the lower
margin of the rib cage. The rectus abdominis muscle, posterior rectus sheath, and transversus
abdominis muscle are identified on the ultrasound. A block needle will be advanced using an
in-plane approach from medial to lateral, targeting the fascial plane between the posterior rectus
sheath and the transversus abdominis muscle. For group 1 patients, 40mL of 0.25%
bupivacaine will be deposited in this fascial plane. For group 2 patients, 40mL of normal sterile
saline will be used instead.
General anesthesia will be maintained with inhalational anesthetic gas. Boluses of fentanyl will
be given to all patients for pain control as needed, regardless of which group they are assigned
to. Patients will also receive muscle relaxants for surgical relaxation as needed. Standard
intravenous antiemetics, 8mg ondansetron and 10mg dexamethasone, will be given at the end
of the surgery prior to extubation, unless otherwise contraindicated. Surgeons will use local
anesthetic to subcutaneously infiltrate the other port sites. Following extubation, patients will
recover in the post-anesthesia care unit (PACU) and then to the general hospital floor. Patients
will be given scheduled intravenous acetaminophen 1000 mg and ketorolac (30 mg), as well as
PRN intravenous opioids, i.e. fentanyl, hydromorphone.
Description of the Source Records that Will be Used to Collect Data about Subjects
Data will be collected from computerized medical record charts including EPIC and
Compurecords. Investigators will also ask subjects questions about items such as their pain,
nausea, and satisfaction with analgesia care.
Description of Data that Will be Collected Including Long-Term Follow-Up
Data collected includes age, gender, BMI, ASA status, duration of surgery, total opioid use in
PACU, total opioid consumption in 24 hours, severity of pain at rest on a Likert scale (0-10) and
presence of postoperative nausea (yes/no) at 1 hour, 6 hours, 12 hours and 24 hours
postoperatively, time to breakthrough pain after surgery, area of pain after surgery, time to
ambulation after surgery, analgesia satisfaction score at time of discharge, and hospital length
of stay.
Where and When Consent will be Obtained
Verbal consent will be obtained via telephone approximately 1-2 weeks prior to the surgery.
Written consent will be obtained on the day of the surgery.
Waiting Period for Obtaining Consent

Patients will receive a written consent form to review at the time that their surgery is scheduled.
Approximately 1-2 weeks prior to surgery, the patient will be contacted by an investigator to
discuss the study in detail, answer all questions and confirm understanding. Subjects will
provide verbal consent for the study via this telephone call. On the day of surgery, they will sign
a written consent form.
Description of Health Information that will be Viewed, Recorded or Generated
The following data will be collected:
1.
Amount of intraoperative IV opioid consumption
2.
Amount of post-operative IV opioid consumption
3.
Severity of pain at rest using an 11-point numeric pain score Likert scale at 1, 6, 12 and
24-hour marks postoperatively
4.
Time to breakthrough pain after surgery
5.
Area of pain after surgery
6.
Presence of postoperative nausea (yes/no) at 1, 6, 12 and 24-hour marks
postoperatively
7.
Time to ambulation after surgery
8.
Analgesia satisfaction score at time of discharge
9.
Hospital length of stay
How PHI will be Protected from Improper Use or Disclosure
Only study investigators will have access to patient data. All research team members must have
completed the institutional HIPAA certification. Extracted data will be stored on the Mount Sinai
Redcap data server, which is stored in accordance to Mount Sinai research policies. A one-way
hash ID will be generated for each record in order to de-identify the subjects. Only study
investigators with access to the full data set will be able to match the hash ID to the original
source. De-identified data will be given to a statistician employed by the Mount Sinai
Department of Anesthesiology for analysis.
When and How PHI will be Destroyed
Following publication of this study, PHI will be destroyed. Digital encrypted files on the Mount
Sinai network will be deleted permanently.
Description of PHI that will be Shared
Age, sex, BMI, ASA status will be shared. All other subject demographics such as name, MRN
or date of birth will not be shared.
Justification for Sharing PHI
De-identified data will be given to a statistician employed by Mount Sinai Department of
Anesthesiology for data analysis.
With Whom Directly PHI will be Shared

De-identified data will be given to a statistician employed by Mount Sinai Department of
Anesthesiology for data analysis.
Location where Data will be Stored
Extracted data will be stored on the Mount Sinai Redcap data server, which is stored in
accordance to Mount Sinai research policies.
Duration Data will be Stored
Data will be stored for the duration of the study until publication. Following publication, the data
will be deleted permanently from the Mount Sinai network.
Steps that will be Taken to Secure the Data during Storage Use and Transmission
Encrypted and secured flash drives and Mount Sinai emails will be used for data transmission.
All study data will be stored electronically in accordance to Mount Sinai Hospital policies.
Data analysis plan including any statistical procedures
Data analysis will be completed by a biostatistician employed by the Department of
Anesthesiology.

Summary of Study Design
●
Inclusion Criteria:
○
Adults 18-80 years old
○
Body mass index >27 and <45 kg/m^2
○
Candidate for general anesthesia
○
Undergoing laparoscopic sleeve gastrectomy
○
Patients of participating surgeons
●
Exclusion Criteria:
○
Prior bariatric surgery of any kind
○
Previous abdominoplasty
○
Allergy or intolerance to one of the study medications
○
ASA > 4
○
Chronic opioid use (taking opioids for longer than 3 months or daily oral morphine
equivalent of >5mg/day for one month)
○
History of alcohol/drug abuse
○
History of hepatic or renal insufficiency
○
Patient refusal
○
Patients who do not speak English
●
Eligible patients identified during surgery clinic → Phone call 1-2 weeks prior to surgery
to discuss study, assess participation, and obtain verbal consent → Written consent
obtained on day of surgery
●
Group allocation information revealed to separate anesthesiologist on the day of surgery
●
Intraoperative Management
○
Induction: propofol, rocuronium, lidocaine, 1.5mcg/kg fentanyl
○
Ipsilateral subcostal TAP block performed
○
Maintenance: sevoflurane, rocuronium as needed, fentanyl as needed
○
Prior to extubation: 8mg ondansetron and 10mg dexamethasone unless
otherwise contraindicated
○
Surgeon will infiltrate other port sites with local anesthetic subcutaneously
●
Following extubation, patients will receive opioids along with scheduled IV
acetaminophen and ketorolac unless otherwise contraindicated
●
Investigator or nurse will assess:
○
Pain at rest using 11-point numeric pain score Likert scale at 1, 6, 12 and 24-hour
marks postoperatively
○
Presence of postoperative nausea (yes/no) at 1, 6, 12 and 24-hour marks
postoperatively
○
Area of most pain after surgery (assessed on postoperative day 1)

○
Analgesia satisfaction score at time of discharge (assessed via telephone call
within 1-2 days of discharge)
●
Data from EPIC
○
Amount of post-operative IV opioid consumption
○
Time to breakthrough pain (time from surgery end to first requirement of IV
opioid)
○
Time to ambulation after surgery
○
Hospital length of stay
●
Data from Compurecord
○
Amount of intraoperative IV opioid consumption

References
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After Surgery (ERAS) Society Recommendations. World J. Surg. 40, 2065–2083 (2016).
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three analgesic schemes (isolated intravenous analgesia, epidural analgesia associated with
intravenous analgesia and port-sites infiltration with bupivacaine associated with intravenous
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