Conditions: Postoperative Pain
Keywords: regional anesthesia cardiac surgery erector spinae
Allocation: NA | Intervention model: SINGLE_GROUP
Enrollment: 45
Healthy volunteers: yes

Brief summary:
To evaluate the efficacy of bilateral continuous erector spinae blocks (BESB) for postoperative analgesia in children and adolescents undergoing cardiac surgical procedures via sternotomy in the Early Recovery After Surgery (ERAS) program in a single arm, open label, interventional study.

Detailed description:
Regional anesthesia-and pediatric regional anesthesia in particular-is a rapidly evolving subfield of anesthesia practice driven with considerable urgency by the growing recognition that even appropriate perioperative opioid administration can have significant deleterious long-term effects.

Regional anesthetics can provide targeted, continuous analgesia to select dermatomes with minimal additional patient risk and as such, have become routine components of opioid-sparing intraoperative and postoperative pain management plans for non-cardiac surgical patients at a single institution. In addition to the postulated benefit of reducing overall opioid exposure (and potentially reducing the risk for long term physiologic and behavioral dependence upon opioids), regional anesthetics may allow for earlier extubation after selected surgeries, shorter intensive care unit (ICU) stays, shorter inpatient admissions, earlier mobilization, fewer gastrointestinal complications, and improved patient and care team satisfaction scores.

Historically, regional anesthetics have been avoided in cardiac surgery as most patients are pharmacologically anticoagulated during their procedures and are thus at increased risk for bleeding. This is particularly worrisome in the pediatric cardiac surgical population as many of these children remain intubated for an extended period of time postoperatively and therefore may not have reliable neurological exams in the setting of neuraxial regional anesthetics-potentially resulting in unrecognized hemorrhage-related acquired neurological deficits.

Recently, the erector spinae block (ESB) has become popular for providing analgesia after a number of anterior chest and abdominal procedures. This simple interfascial plane block can reliably provide unilateral chest and/or abdominal wall analgesia. It has been described in numerous case reports and case series as an effective block for management of unilateral thoracotomies, unilateral rib fractures, unilateral abdominal incisions and most notably, for management of post-sternotomy pain when applied bilaterally. New case reports and series involving the ESB are being published almost weekly with a growing number of manuscripts specific to cardiac surgical applications. Indeed, numerous randomized controlled trials have investigated the analgesic efficacy of bilateral erector spinae plane blocks (BESB) compared with conventional treatment for pain after cardiac surgery in adult patients and have been published recently (2018-2019) with promising results.

As an interfascial plane block in a compressible anatomical space, the ESB is considered safe in anticoagulated (or recently anticoagulated) patients. It is fast becoming a preferred anesthetic option at BCH for anticoagulated patients - as opposed to neuraxial (e.g. epidural) and paraneuraxial blocks (i.e. paravertebral) nerve blocks, which are largely contraindicated in this setting. Further, given its relative ease of placement, apparent efficacy and safety profile, it is increasingly becoming a standard option for patients undergoing a wide range of thoracic, abdominal and thoraco-abdominal procedures.

The investigators recently investigated the feasibility of performing these blocks bilaterally in a pediatric cardiac surgical population undergoing sternotomy-based procedures (IRB-P00031524). At the conclusion of this 10-patient pilot, the investigators found that performing these blocks was technically feasible, requiring 30 minutes or less of OR time, resulting in no known complications. Furthermore, the data suggested an approximate 25% reduction in rescue opioid requirements in the first 48 hours amongst the erector spinae group (p=0.048).

In order to best evaluate the efficacy of this block in the pediatric cardiac population, a blinded, randomized and controlled trial would be ideal. However, given that randomization could be challenging and the fact that blinding would not be feasible, the investigators believe an observational prospective cohort study is most appropriate at this time.

As such, the investigators propose to evaluate the comparative efficacy of BESB versus matched historical controls who received standard of care pain management (systemic opioid therapy) for patients undergoing cardiac surgery via sternotomy by means of a single arm, open label, interventional study that will compare as the primary outcome rescue analgesic requirements, rendered as opiate equivalents, at 12, 24 and 48 hours, and the 24 hour period preceding both 72 and 96 hours postoperatively. 'Efficacy' will be considered as a threshold of clinical significance being defined as a 15% difference). In addition to the primary endpoint, we plan to evaluate the duration of intubation, length of ICU stay, median pain scores, incidence of PONV (postoperative nausea and vomiting; 0-6h, 6-12h and overall), time to mobilization and adverse events between these groups. Postoperative data collected from standard clinical follow-up tools, such as return to baseline sleep and activity status as well as pain medication requirements at home, will also be compared. In addition, the investigators plan to evaluate the quality of sleep and activity with a smart watch (Fitbit™ ) during the perioperative period in the BESB group only.

Arms:
arm 1: All enrolled patients will have bilateral erector spinae blocks (with catheters for postoperative local anesthetic infusion) placed by the by a member of the clinical regional anesthesia team (under the supervision of a member of the research team) in a sterile fashion after the cardiac surgical procedure is completed. Postoperative continuous infusion of local anesthetic (ropivacaine) via the nerve block catheter is initiated and managed by the Acute Pain Service (per standardized, clinical weight-based protocols).

Interventions: intervention 1: Bilateral erector spinae blocks using ropivacaine
Intervention descriptions: intervention 1: Bilateral chest wall nerve blocks using ropivacaine.

Protocol document:
Prot_SAP_000.pdf: 
 
 
 
 
 
 
 
 
 
 
 
 
 
Bilateral Continuous Erector Spinae Blocks for Post-Sternotomy Pain Management: A 
Single Arm Interventional Study. 
NCT04567407 
10/25/2021 
 
 


 
 
 
CHeRP IRB Additional Protocol Information: 
     In addition to the CHeRP SmartForms, all protocols must include the following sections. If a section is 
not applicable for the current protocol please indicate why this is the case. Please note that a complete 
protocol* consists of the CHeRP forms and the information provided in this form. 
  
TITLE: 
Bilateral Continuous Erector Spinae Blocks for Post-Sternotomy Pain Management: 
A Single Arm Interventional Study. 
  
A. Specific Aims/Objectives: 
Overall Aim: To evaluate the efficacy of bilateral continuous erector spinae blocks 
(BESB) for postoperative analgesia in children and adolescents undergoing cardiac 
surgical procedures via sternotomy in the Early Recovery After Surgery (ERAS) 
program in a single arm, open label, interventional study. 
Specific Aims:  
1. Evaluate the utility of BESB in cardiac surgical patients by assessing the pain 
scores, opioid consumption, and complications related to BESB. 
2. Compare intra- and postoperative opioid use in patients receiving BESB vs. 
matched historical controls who did not receive BESB in the ERAS program. 
3. Compare clinical outcomes between the 2 groups: duration of mechanical 
ventilation, time to mobilization, pain scores (median pain score per period), 
intensive care unit length of stay (LOS), incidence of postoperative nausea and 
vomiting, postoperative complications, hospital LOS, readmissions, mortality, 
recovery to baseline activity and sleep post discharge, total and rescue opioid 
pain medication requirements.  
4.  Evaluate quality of sleep and activity with (Fitbit™ ) smart watch device of 
patients receiving BESB during the postoperative period.  
Hypothesis: The investigators hypothesize that BESB is efficacious with respect to 
pain control and will lead to a 15% or greater reduction of consumed opiate 
equivalents at 12, 24 and 48 hours, and the 24-hour period preceding both 72 and 


96 hours postoperatively compared to matched historical controls who received 
standard of care pain management (systemic opioid therapy).  
 
B. Background and Significance: 
Regional anesthesia—and pediatric regional anesthesia in particular—is a rapidly 
evolving subfield of anesthesia practice driven with considerable urgency by the 
growing recognition that even appropriate perioperative opioid administration can 
have significant deleterious long-term effects1. 
Regional anesthetics can provide targeted, continuous analgesia to select 
dermatomes with minimal additional patient risk and as such, have become routine 
components of opioid-sparing intraoperative and postoperative pain management 
plans for non-cardiac surgical patients at BCH. In addition to the postulated benefit 
of reducing overall opioid exposure (and potentially reducing the risk for long term 
physiologic and behavioral dependence upon opioids), regional anesthetics may 
allow for earlier extubation after selected surgeries, shorter intensive care unit 
(ICU) 
stays, 
shorter 
inpatient 
admissions, 
earlier 
mobilization, 
fewer 
gastrointestinal complications, and improved patient and care team satisfaction 
scores. 
Historically, regional anesthetics have been avoided in cardiac surgery as most 
patients are pharmacologically anticoagulated during their procedures and are 
thus at increased risk for bleeding. 2-5 This is particularly worrisome in the pediatric 
cardiac surgical population as many of these children remain intubated for an 
extended period of time postoperatively and therefore may not have reliable 
neurological exams in the setting of neuraxial regional anesthetics—potentially 
resulting in unrecognized hemorrhage-related acquired neurological deficits.  
Recently, the erector spinae block (ESB) has become popular for providing 
analgesia after a number of anterior chest and abdominal procedures.7-10 This 
simple interfascial plane block can reliably provide unilateral chest and/or 
abdominal wall analgesia.11 It has been described in numerous case reports and 
case series as an effective block for management of unilateral thoracotomies, 
unilateral rib fractures, unilateral abdominal incisions and most notably, for 
management of post-sternotomy pain when applied bilaterally.12,13 New case 
reports and series involving the ESB are being published almost weekly with a 
growing number of manuscripts specific to cardiac surgical applications.14,15 
Indeed, numerous randomized controlled trials have investigated the analgesic 
efficacy of bilateral erector spinae plane blocks (BESB) compared with 


conventional treatment for pain after cardiac surgery in adult patients and have 
been published recently (2018-2019) with promising results.16 
As an interfascial plane block in a compressible anatomical space, the ESB is 
considered safe in anticoagulated (or recently anticoagulated) patients.17 It is fast 
becoming a preferred anesthetic option at BCH for anticoagulated patients - as 
opposed to neuraxial (e.g. epidural) and paraneuraxial blocks (i.e. paravertebral) 
nerve blocks, which are largely contraindicated in this setting. Further, given its 
relative ease of placement, apparent efficacy and safety profile, it is increasingly 
becoming a standard option for patients undergoing a wide range of thoracic, 
abdominal and thoraco-abdominal procedures. 
We are fortunate at BCH to have the largest pediatric cardiac surgical program in 
the United States. We also have an active, and well organized regional anesthesia 
service.  We are in a unique position to more thoroughly evaluate the effectiveness 
and safety of regional anesthetics in children following cardiac surgery. 
Furthermore, we feel it is critical that institutions such as BCH take a leading role 
in documenting the effects of regional anesthesia on the most important outcome 
measures when considering perioperative medicine. These include: overall pain 
management, surgical healing, functional recovery, long term pain symptoms, and 
emotional/behavioral outcomes after surgery. 
Indeed, given these considerations, our group recently investigated the feasibility 
of performing these blocks bilaterally in a pediatric cardiac surgical population 
undergoing sternotomy-based procedures (IRB-P00031524).  At the conclusion of 
this 10-patient pilot, our group found that performing these blocks was technically 
feasible, requiring 30 minutes or less of OR time, resulting in no known 
complications. Furthermore, our data suggested an approximate 25% reduction in 
rescue opioid requirements in the first 48 hours amongst the erector spinae group 
(p=0.048). 
During the short time required to complete our pilot study, several additional adult 
studies of improved size and quality have been published demonstrating favorable 
outcomes with this block for a variety of indications, including post-sternotomy 
care. As such, it has effectively become an accepted practice in the larger 
community and here at BCH as well, with surgeons, anesthesiologists, and families 
frequently requesting an ESB (unilateral or bilateral) as a part of the care they 
either provide or receive. We believe we have reached a point of clinical equipoise 
in relation to the existing standard of systemic opioid therapy and seek to evaluate 
the relative efficacy of this technique in a pediatric cardiac surgical population at 
BCH. 


In order to best evaluate the efficacy of this block in the pediatric cardiac 
population, a blinded, randomized and controlled trial would be ideal. However, 
given that randomization could be challenging and the fact that blinding would not 
be feasible, we believe an observational prospective cohort study is most 
appropriate at this time. 
As such, we propose to evaluate the comparative efficacy of BESB versus matched 
historical controls who received standard of care pain management (systemic 
opioid therapy) for patients undergoing cardiac surgery via sternotomy by means 
of a single arm, open label, interventional study that will compare as the primary 
outcome rescue analgesic requirements, rendered as opiate equivalents, at 12, 24 
and 48 hours, and the 24 hour period preceding both 72 and 96 hours 
postoperatively. ‘Efficacy’ will be considered as a threshold of clinical significance 
being defined as a 15% difference). In addition to the primary endpoint, we plan to 
evaluate the duration of intubation, length of ICU stay, median pain scores, 
incidence of PONV (postoperative nausea and vomiting; 0-6h, 6-12h and overall), 
time to mobilization and adverse events between these groups. Postoperative data 
collected from standard clinical follow-up tools, such as return to baseline sleep 
and activity status as well as pain medication requirements at home, will also be 
compared. In addition, we plan to evaluate the quality of sleep and activity with a 
smart watch (Fitbit™ ) during the perioperative period in the BESB group only. 
 
C. Preliminary Studies 
While the paravertebral block and, increasingly, the ESB are commonly used for 
postoperative management of numerous thoracic procedures in adults and 
children, there is little prospective data available evaluating the efficacy of these 
blocks in this population and no prospective data evaluating the utility of such 
blocks for management of post-sternotomy pain in a pediatric population. 
Retrospective studies and case reports exist that suggest that ESBs are efficacious 
and low risk, but very few prospective data exist. The ESB has been described as 
having utility in the adult perioperative environment for patients undergoing 
breast surgery19, shoulder surgery20, thoracotomy/thoracoscopic surgery9,21, 
thoracic spinal surgery,22 and ventral abdominal surgery7.  Two case reports have 
also described its utility in treating patients with chronic pain in the thoracic 
dermatomes.23 As noted above, there is at least one published prospective study in 
adults,16 but similar studies in pediatric patients are yet to be undertaken. In 
general, there is much less published evidence in children; however, there are case 
reports and case series describing its use for patients undergoing thoracic and 
abdominal surgery12,24-26.  


Large retrospective analyses of multiple pediatric regional anesthesia registries 
consistently report a very favorable safety profile for the provision of regional 
anesthetics in the pediatric population. A recent (2015) consensus statement from 
the American and European Societies of regional anesthesia (ASRA and ESRA) 
reported the risk profile of administering regional anesthetics to anesthetized 
children, citing a risk of postoperative neurologic symptoms of 0.93/1000 cases 
(>90% of which resolve completely within 1 month) and a rate of local anesthetic 
systemic toxicity of 0.08/10000 cases.27 
As previously noted, our group recently investigated the feasibility of performing 
BESBs in a pediatric cardiac surgical population undergoing sternotomy-based 
procedures at this institution. At the conclusion of this 10-patient pilot, we found 
that performing these blocks was technically feasible -- requiring 30 minutes or less 
of OR time -- and resulted in an approximate 25% reduction in rescue opioid 
requirements in the first 48 hours amongst the BESB group (p=0.048). There were 
no significant adverse events noted during this pilot with the exception of a single 
instance of a kinked (but useable) catheter. 
While the numbers at BCH are relatively small, retrospective analyses of ESBs 
performed in this institution in non-cardiac surgery have demonstrated no 
evidence that this block type is associated with any greater risk than that 
demonstrated by aggregate block data from the various pediatric regional 
anesthesia registries. Information currently available suggests that regional 
blockade, when performed properly, carries a very low risk of morbidity and 
mortality in appropriately selected infants and children.28 Furthermore, we have 
found no evidence of increased adverse events present in the ESB patients when 
compared to patients receiving other regional anesthetics in our local analysis. 
Indeed, two abstracts addressing the safety and efficacy of ESB blocks in BCH 
patients have recently been accepted for presentation at the major regional 
anesthesia conference.29,30 
 
D. Design and Methods 
(1)    Study Design 
We propose a single arm, open label, interventional study to compare the opiate 
requirements of 45 patients who consent to receive BESB catheters following 
cardiac surgery via sternotomy versus 90 matched historical controls who had 
similar surgical procedures but without BESBs. 
Patients meeting eligibility criteria will be recruited and enrolled to have BESBs 
placed for postoperative pain control as a part of their perioperative anesthetic 


plan. These patients will subsequently have a variety of preoperative demographic 
and functional data collected as well as data related to their surgeries and 
postoperative course all collected for later analysis. This enrolled group of patients 
will subsequently be compared regarding these outcome measures with a 1:2 
matched, retrospective analysis of patients in the cardiac surgical ERAS program 
who did not receive regional blocks as a component of their anesthetic care. (The 
ERAS Cardiac program is a heart center perioperative evidence-based quality 
initiative. Retrospective data analysis of outcomes for patients in this program is 
performed for quality improvement purposes and outcomes research [IRB 
P00029161 – PI: Nathalie Roy MD, co-investigators: Roland Brusseau MD, Morgan 
Brown MD]). Children aged 2 years through 17 years meeting entry criteria will be 
screened and recruited for participation from the Boston Children’s Hospital 
cardiac surgical program. 
 
 (2)   Patient Selection, Inclusion/Exclusion Criteria and Recruitment 
Method 
Patients from BCH who meet the criteria below will be considered for recruitment: 
Inclusion Criteria: 
1. 
Scheduled as part of the cardiac surgical ERAS program: Patients scheduled 
for elective surgeries for the following congenital anomalies, or similar: atrial septal 
defects (all types), partial anomalous pulmonary venous connection (non-
obstructed), cor-triatriatum, VSD, partial AV canal, sub-aortic membrane resection, 
anomalous aortic origin of the coronary arteries, and pulmonary valve/conduit 
implantation 
2. 
Scheduled to undergo a first time surgical pulmonary valve or right ventricle 
to pulmonary artery conduit change in anatomic position, in the context of previous 
complete repair.    
3.     
Ages 2 years through 17 years. 
 
Exclusion Criteria: 
1.    Single ventricle physiology. 
2.    Significant scoliosis or other anatomic contraindications to ESB. 
3. Significant intraoperative hemodynamic instability or bleeding, as 
ascertained by clinicians taking care of the patient. 
4.    Patients with severe neurodevelopmental delays. 


5.    Patients with previous chronic pain syndromes. 
6.  Patients with a history of greater than 24 hours of postoperative or post-
procedural opioid treatment at any point in the 2 months prior to surgery. 
7.    Lack of parental consent and/or child assent. 
 
Recruitment Method: 
We plan to include pediatric patients who are scheduled for inpatient surgery 
at BCH over a period of 2 years. Patients will be recruited by members of the 
study staff. We will contact all patients and/or families scheduled for an eligible 
ERAS procedure (see below for details of contact methods) and otherwise meet 
criteria. 
Each morning, a designated member of the study staff will review the upcoming 
surgical schedule to identify pediatric cases that fit the study criteria 
(procedure type and age). If these criteria are met, the case will be sent to an 
investigator for further clinical review. A final eligibility decision will be made 
by the PI. 
 
1. 
Outpatients with procedures scheduled >2 weeks from identification: 
Patients will be sent information on the study (cover letter, brochure, 
consent form) up to 2 weeks prior to their surgery or scheduled 
preoperative visit.  This will be sent either by USPS mail or by secure 
electronic mail if an e-mail is on file. 
2. 
Outpatients with procedures scheduled 2 weeks or less from 
identification: Patients will be contacted by secure electronic email and/or 
given informational materials at their preoperative visit if we are unable to 
send mailers reliably VIA USPS.  We will allow at least a day for them to 
consider participating in the study. 
3.     
Outpatient telephone follow-up: Patients sent information packets 
either by USPS or secure electronic email may be contacted by telephone to 
confirm receipt of the materials and answer any initial questions after such 
time as they would normally be expected to have received and reviewed the 
packets (the next week for USPS and no sooner than 1 day following email). 
If materials have not been received, patients will be given the opportunity 
to have those materials sent or be contacted at a preoperative visit. 
4.    Inpatients with no planned discharge and/or preoperative clinic 
appointments: Patients who are already inpatient will be approached on the 


patient floor or other inpatient encounter with study information. We will 
approach as soon as we have confirmed eligibility and will provide them 
with recruitment materials prior to their day of surgery and allow at least 
24 hours for a decision to be made. 
5.  
International patients: For international patients meeting entry 
criteria, recruitment materials will not be mailed internationally. If an e-mail 
is available for an eligible international patient, a secure e-mail via BCH 
server will be sent to the family. The e-mail will include all approved 
recruitment documents. If we are unable to reach an international family via 
e-mail, eligible international patients and their families will be approached 
and provided materials in the preoperative clinic. At this time we will 
provide information about the study, answer all questions and allow at least 
24 hours for them to consider participating in the study. 
6.    When feasible, consent will be obtained either at the time of the 
preoperative visit, on the day of surgery, or at the bedside for those who are 
inpatient (i.e. without pre-op appointments). When in person consent is not 
feasible, the research team will have the consent discussion by phone prior 
to the day of surgery and families will be asked to provide written consent 
following that discussion. Written consent may be done through the RCS e-
consenting platform or by sending the consent to the home by mail or email 
and receiving a signed copy of the consent back by mail or email.  
7. In the exceptional situation when bilateral erector spinae blocks are used 
clinically and the patient or family were not approached for the study 
because of changes in the surgical schedule or other special situation, the 
research team can approach the families to offer participation in the study 
if they meet entry criteria. 
We have numerous recruitment strategies as cardiac surgical scheduling is 
very fluid, often with cases added only days before. Our recruitment scheme 
allows for physical and electronic mail, on-site (clinic, inpatient) encounters, 
and phone calls to assess interest. We allow ourselves a maximum of 3 
patient contacts. Consent may be taken at any time a patient feels 
comfortable to do so, but never with less than a day for patients/families to 
think or (re)consider. While we do allow ourselves to take consent on the 
day of surgery, we would not endeavor to meet the patient, describe the 
study, and take consent all at once on immediately prior to being taken into 
the OR for the procedure and would ensure that this would be done a 
minimum of 24h prior. 


It will be made clear to all eligible participants that while BESBs are used in other types of 
patient groups, they are not typically used for patients undergoing congenital cardiac 
surgery via a sternotomy at BCH, and are therefore considered to be under investigation 
in this study. Families will be informed that the study is being done to better understand 
if using ESBs bilaterally is an effective form of pain management for patients undergoing 
sternotomy when compared to a set of matched historical patients who did not receive 
BESBs, and whose pain management includes a multimodal pain strategy, cornerstone of 
the ERAS Cardiac program. Research staff will stress that if families elect not to participate, 
they will not receive the BESBs unless agreed upon with their primary anesthesia team, 
but instead the standard of care pain management at BCH (multimodal pain regimen 
including pain-score based systemic opioid therapy as part of the ERAS Cardiac program 
guideline and orderset).   
 (3)   Description of Study Treatments or Exposures/Predictors  
Participants will have their medical record reviewed following enrollment for 
demographic information including: gender, age, weight and height, procedure, 
surgeon, and current and historical medication use. 
Any other routine standard-of-care data will be collected preoperatively as well in 
addition to research-specific data points. 
All enrolled patients will have bilateral erector spinae blocks (with catheters for 
postoperative local anesthetic infusion) placed by the by a member of the BCH 
regional anesthesia team (under the supervision of a member of the research team) 
in a sterile fashion after the cardiac surgical procedure is completed. The placement 
is as follows: 
 
 The patient is placed in a lateral decubitus position (left or right), with all 
pressure points padded in routine fashion. 
  The area for intervention is prepped with a chlorhexidine solution, and 
sterile drapes are applied to demarcate the block placement area. 
 The T4/5 transverse process on one side is identified with the ultrasound 
transducer in a parasagittal orientation. 
 An 18g Tuohy needle is advanced to the target area under direct ultrasound 
visualization. The needle tip is advanced until it contacts the transverse 
process, just below the erector spinae muscle complex. 
 Normal saline is injected to confirm appropriate needle tip position.  The 
erector spinae muscle is visualized to be elevated up off of the transverse 
process with normal saline injection 
 With confirmation of appropriate needle tip position, the initial local 
anesthetic bolus is injected using a standard, weight-based dosing protocol. 


 Following the bolus injection, a catheter is threaded into the space occupied 
by the local anesthetic bolus. 
 Catheter tip position is verified by one or more of the following: ultrasound 
visualization of the catheter tip, ultrasound visualization of instilled normal 
saline and/or ultrasound visualization of a small hyperechoic (i.e. bright on 
ultrasound) injection of air. 
 With the catheter tip position identified, the catheter is tunneled to a 
cutaneous exit point approximately 2-3cm from the incision using a 
Crawford needle. 
 The catheter is dressed in standard fashion with an adhesive catheter 
anchor, Dermabond, Mastisol, Tegaderm and tape. 
 This is repeated for the contralateral side. To the extent possible, this will be 
done without repositioning in a contralateral decubitus position. 
 A label indicating that each catheter is a nerve-block catheter with its 
laterality and date of placement noted is applied to each catheter. 
 Catheter placement is complete. 
 Postoperative infusion of local anesthetic (ropivacaine) via the nerve block 
catheter is initiated and managed by the Acute Pain Service (per 
standardized, clinical weight-based protocols). 
 Procedural notes: 
o Minor deviations from the above procedure (e.g. small changes in 
sequence, needle entrance locations, amount of catheter deployed, 
etc.) are possible as the anatomy, positioning, etc. of individual 
patients varies. This is anticipated and allowable so long as such 
modifications remain within what is currently considered standard 
of care for the placement of these blocks and what is done in a given 
case is considered the appropriate standard of clinical care for that 
patient by the clinical providers placing the block(s). 
  
All patients will have access to the multimodal pain regimen which is standard of 
care for all ERAS Cardiac patient and includes acetaminophen and ketorolac, when 
otherwise not contraindicated, as well as pain-score based opiate rescue 
medications as needed. All patients have access to postoperative pain management 
as needed by means of  a standard opioid-based PCA/NCA demand protocols 
utilized at BCH if needed.  In addition, all enrolled patients will be followed by the 
Acute Pain Service at BCH as is the standard of care for all patients receiving nerve 
blocks, enabling access to additional assessment, catheter and infusion 
management (where appropriate) and opioid treatment as needed 24 hours a day, 
7 days a week. In addition, one of the primary investigators will be available to the 


Acute Pain Service staff for consultation 24 hours a day regarding any desired 
consultation on study patients.   
 
Possible risks related to the block include bleeding, infection, local anesthetic 
systemic toxicity, local anesthetic insensitivity and incomplete block and/or block 
failure. These risks occur at no greater (or lesser) frequency than when associated 
with the use of such blocks in routine clinical situations. 
 
Intraoperative and postoperative anesthetic and surgical data, routinely collected 
for the Society of Thoracic Surgery (STS), will be collected from the EMR. 
 
In addition to observational tools and subjective scoring, patient functional status 
(activity, sleep quality and other measures) will be assessed by actigraphic analysis 
using the Fitbit™ Charge 3 smartwatch. A Fitbit™ will be placed on the non-dominant 
arm, if possible, after extubation on the day of surgery. The Fitbit™ will remain on 
the patient until discharge from the hospital (which on average is about 5 days 
post-op) and the actigraphic data subsequently will be downloaded to the secure 
research database and the data wiped from the device. If a study subject had an 
unforeseeable complication and they no longer progressed along the standard 
recovery path (e.g. re-intubation, return to ICU), or if the watch was interfering in 
clinical care in any way, the Fitbit™ would be removed. 
Following primary data collection for the enrolled subjects, each subject will be 
matched by surgical procedure using the STS procedure code, to 2 patients within 
the cardiac surgery ERAS program QI database (IRB #P00029161 which allows 
retrospective data analysis of outcomes) by the research team. All patients 
recruited for this study are themselves already part of the enhanced recovery after 
cardiac surgery clinical program [QIP]. Matching will be performed 1:2 with respect 
to surgical procedure and diagnosis using the STS codes, within 30% of the study 
patient’s age and according to gender (if possible) and will be blinded to outcomes.   
Thus, up to 90 additional patients will be included in this study, retrospectively in 
addition to the 45 study patients  from the single arm interventional cohort study 
(BESB).  
 
Groups will be compared for demographic data, risk factors (from the STS 
database), diagnosis, procedure and cardiopulmonary bypass and clamp times to 
ensure their similarities 


 
E. Definition of Primary and Secondary Outcomes/Endpoints 
 Primary: 
 Analgesic requirements, rendered as opiate equivalents, at 12, 24 and 48 
hours, and the 24 hours preceding both 72 and 96 hours postoperatively. 
 Secondary: 
 Analgesic requirements, rendered as total opiate equivalents, at 12, 24 and 
48 hours, and the 24-hour period preceding both 72 and 96 hours 
postoperatively. 
 Duration of intubation following OR exit. 
 Duration of ICU stay following OR exit. 
 Duration of inpatient admission. 
 Median pain scores collected per standard of care (VAS, NRS, INRS, or 
FLACC) at 0-3h, 3-6h, 6-12h, 12-24h, 24-36h and 36-48h. 
 Incidence of postoperative nausea and vomiting during the following time 
ranges: 0-6h, 6-12h, 12-24h, and overall 
 Time to mobilization (e.g. up to chair, ambulation). 
 Quality/Quantity of mobilization and sleep via postoperative actigraphy. 
 Outcome and satisfaction measures associated with routine perioperative 
questionnaire responses. 
 Adverse events. – catheter, hemodynamic instability during placement (new 
inotrope or vasopressor – including Ca, volume > 5ml/Kg, variation 10% 
baseline SBP and MAP) 
 All major Society of Thoracic Surgeons (STS) standard indices of morbidity 
and mortality 
 
*Of note, all of the above data points are collected automatically (via the 
electronic medical record) for all patients, as a part of their routine clinical 
care, regardless of whether or not they participate in the study.  
 
F. Data Collection Methods   
All patients will be assigned a unique personal identifier that will not be linked to 
any patient identifying information. Data will be collected during the study in case 
report forms and then will be entered into a password-protected, secure database 
or automatically collected via the Regional Anesthesia Outcomes Database and 
uploaded to that same database. 


With the exception of actigraphic data, all preoperative demographic information 
and intraoperative data will be extracted from the patients’ EMR and loaded into 
the secure database. 
Each subsequent day, appropriate data will be extracted from the EMR to the secure 
database for later analysis. In addition to the parameters described above, various 
other catheter-related and adverse outcome data points will be captured from the 
EMR and uploaded to the secure database for further analysis. Catheter boluses and 
catheter rate adjustments (if present) will be recorded as well. 
Research information collected on paper (or other physical media) during the study 
will be stored in locked cabinets with access limited to the Principal Investigator 
and research personnel affiliated with the study. Information that has been 
generated as, or transferred to, electronic media will be kept on password 
protected, secured data servers. All health information is protected by HIPAA 
(Health Insurance Portability and Accountability Act) and all health records will be 
kept confidential. Patients’ birthdate, name, and all other identifying information 
will be removed when analyzing and reporting the data. Any personal identifying 
information will be stored separately from the other information provided by or 
about the patient and no personal identifying information will be reported in any 
publications or presentations. Identifying information will be kept in a password 
protected, secure file with limited access by research personnel. Once data 
collection is complete, identifying information will be destroyed. 
  
G. Data Management Methods 
All relevant information retrieved from the electronic medical record, by the PI 
and/or a member of the research team will be translated into an electronic form. 
Data collected on paper case report forms will be entered into a standard, secured 
database for intake and checking, and will be protected by encryption and 
password. Only authorized users are permitted access to the data files, and daily 
server back-up activities are executed to ensure data safety. All data will be stored 
on a password-secured research computer, and all data entered into the computers 
will be password protected.  Procedures to ensure accurate and reliable data 
collection will include well-designed data forms and training. 
  
H. Study Timeline 
We plan to enroll a total of 45 patients in this single arm, open label, interventional 
study.  We anticipate that it will take approximately 2 years to complete enrollment 
and data collection for this study. 


  
I.  Adverse Event Criteria and Reporting Procedures 
Adverse or unanticipated events will be reported as required to the Boston 
Children’s Hospital IRB by the PI according to institutional reporting requirements. 
An Adverse Event refers to any untoward medical occurrence whether or not it is 
considered intervention-related. 
As noted above, analysis of the retrospective outcomes data for the 45 BCH patients 
treated with ESBs, the patients in our trial study, and the national and international 
literature demonstrates no evidence that this block type is associated with any 
greater risk than that demonstrated by aggregate block data from the various 
pediatric regional anesthesia registries. Information currently available suggests 
that regional blockade (including the erector spinae block), when performed 
properly, carries a very low risk of morbidity and mortality in appropriately 
selected infants and children.28 
Nevertheless, as there exist little prospective outcomes data related to the ES block, 
we will implement a rigorous system to follow and report any adverse events, 
including interim analyses by a non-blinded statistician, as described below: 
  
Adverse Event Monitoring: 
Adverse outcomes will be carefully tracked for all patients enrolled in the study.   
Enrollment will be halted and the IRB informed by the PI if any of the following 
conditions are met: 
 
 1 of any of the following serious adverse events. 
o Patient death. 
o Pneumothorax directly resulting from placement or removal of the 
blocks and catheters as evidenced by: 1- lung puncture during 
placement resulting in a moderate to large pneumothorax on the side 
affected performed within 8 hours, and/or the development of a new 
air leak in an existing chest tube collection system. 2- The development 
of a new moderate to large pneumothorax within 8 hours after removal 
of Erector Spinae plane catheters. 
o Hematoma at the site of the catheter/block—causing pain or any 
neurological symptoms for the patient. 
o Persistent neurologic symptoms lasting more than 3 days after a single 
shot block or catheter is removed. 


o Local anesthetic systemic toxicity (any symptoms leading to this 
diagnosis by a study team participant) 
 >2 of any of the following minor/moderate adverse events in a given patient 
or >10 in aggregate: 
o Persistent bleeding at the site of the catheter insertion or block 
placement. 
o Leakage of local anesthetic from the catheter insertion site that leads 
to discontinuation of the catheter infusion. 
o Redness or superficial infection of the catheter site or site of the block 
placement. 
o Skin irritation at the site of the catheter insertion or block placement 
that results in greater than 3 cm of induration or is associated with 
pain.   
In addition to these stoppage rules, we plan to have Dr. Meena Nathan MD (Director 
of Quality and Safety, Cardiac Surgery, BCH) independently review the case outcomes, 
etc. to ensure patient/subject safety in a way that may not be captured by the above 
stoppage rules. This monitor will make such assessments for each cohort of 15 
patients. As Dr. Meena is not a part of the study team, these reviews need not be 
blinded/redacted/etc. in any way. Any concerns raised by Dr. Meena will be brought 
to the attention of the PI directly and the IRB as well in a timely fashion. 
 
If there is a pause for any of the above reasons, continuance of the protocol will be at 
the discretion of the IRB in consultation with the study team. No individual care data 
will be reported unless there is a serious adverse effect. Reports will be done in an 
aggregated fashion. 
  
Special note regarding ropivacaine: 
Ropivacaine use constitutes the standard of care at BCH for all nerve blocks and 
regional anesthetics, including cardiac surgical ERAS patients. Known potential 
adverse consequences of this mode of delivery of this medication include 
hypersensitivity, allergic reaction, hypotension and cardiac arrhythmias if injected 
intravascularly. The presence of any of these will be assessed by the primary 
anesthesiologist intraoperatively and treated appropriately at the time of block 
placement and initial bolus and further assessed for such daily by members of the 
research team and Acute Pain Service. Any occurrence of a possible adverse event 
or events will be documented and reported to the DSMB, the IRB and the 
Department of Anesthesia Quality Assurance Physician as appropriate. In the event 


of a serious adverse event, it will be reported to the DSMB and IRB immediately and 
the study halted until a thorough investigation into the cause can be made. 
The relative safety of ropivacaine for use in regional anesthesia is supported by the 
information contained the Pediatric Regional Anesthesia Network (PRAN) 
database. The PRAN is a consortium of major pediatric centers in North America 
that manages a prospective data registry on pediatric regional anesthesia. From 
their database, which at this time comprises more than 130,000 pediatric regional 
anesthetics from numerous major centers in the US and Canada, ropivacaine is 
documented to be used in greater than 85% of pediatric regional with a safety 
profile at least equivalent to, if not better than, bupivacaine.31 
Further, ropivacaine is very well studied in pediatrics. There is an extensive body 
of prospective clinical trials and clinical outcomes studies on ropivacaine 
pharmacokinetics, safety and clinical outcomes from infancy through adolescence.   
Our prescribing practices at BCH in the Regional Anesthesia and Acute Pain 
Services are derived from that body of PK information and consensus 
recommendations.  
We therefore regard ropivacaine as the established standard of care for pediatric 
regional anesthesia and have selected it for use in this study. 
  
J.  Quality Control Method 
Data quality control will be assured through automated and manual methods. The 
study database enhances data quality through required entry fields for critical data 
and automatic flags for missing or out-of-range data. Efforts will be made to 
minimize data entry error by the development of a user-friendly database and all 
data entry will be double-checked with the source files. Data will be audited for 
accuracy by investigators after being entered into the database. 
  
K.  Data Analysis Plan 
At the time of data analysis, de-identified datasets will be downloaded from the 
secure database and merged into secure statistical analysis tool for purposes of 
analysis. Missing data will be accounted for when the data is coded into respective 
variables. 
Descriptive statistics will be generated in order to summarize demographic 
characteristics of patients enrolled. Data will be tested for normality using the 
Shapiro-Wilk test. Data will be presented as total n (%), means and standard 
deviations (SD) if the distribution appears normal, or medians and range when not.   


Assuming normality, t-tests will be conducted to investigate the differences 
between the two exposure groups (to compare total opioid equivalents, time 
required to place the block, time to extubation, and time to discharge, etc.). If data 
does not appear to be normal, Wilcoxon Rank Sum/Mann-Whitney tests will be 
used for group comparisons. Repeated measure analysis will be used to compare 
pain scores over time between groups and when compared to baseline values.  
Adverse events and complications (if any) associated with the blocks will be 
recorded and categorized. Fisher’s exact test will be used to compare the 
proportion of patients who reported adverse events between the two groups. 
P<0.05 will be considered statistically significant. 
Should a clinically significant effect be demonstrated, healthcare costs related to 
the surgical encounter for both groups will be approximated and compared in order 
to better assess the added value of the intervention in a more global fashion. 
 
L.  Sample Size Considerations 
In order to evaluate the efficacy of BESB in this cardiac surgical population 
compared to those who did not receive blocks, we have defined ‘efficacious’ as 
denoting an at least 15% difference in the total opioid consumption at 96hours 
based on the historical rescue opiate data in the matched cohort. Assuming an alpha 
of 5%, 80% power, and the mean opiate requirements found in our pilot study, we 
estimate that a total sample size of 38 patients undergoing sternotomy with BESBs 
and 76 matched controls are needed to demonstrate efficacy of the new treatment 
(BESB).  
Table 1 (below) demonstrates that, using a 1:2 ratio of BESB:standard ERAS 
patients, 38 BESB and 76 standard ERAS patients are required to detect a 0.18 mean 
difference (15% relative reduction associated with BESB) in square-root Total (96-
hr) OME between groups with 80% power using a two-sided 0.05-level test.  
Because the coefficient of variation for 48-hour OME is somewhat smaller, this 
sample size will provide 87% power to detect a 15% relative reduction (0.16 mean 
difference) in square-root 48-hr OME between groups using a two-sided 0.05-level 
test. 
Because the larger SD of the two groups from background data (see Table 2) was 
used in these calculations, and because the groups will be matched on several 
patient characteristics which will minimize variation, these assumptions are 
conservative and power to detect the effect sizes shown in Table 1 may be even 
higher than shown. 
 


Table 1.  Required Sample Size to Detect BESB vs. ERAS Group (1:2 Ratio) 
Reductions in 48- and 96-hour OME (square-root transformed) assuming two-
sided α=0.05, 80%/85% Power, 48-hour mean sqrt OME 1.05 and 96-hour mean 
sqrt OME 1.23 in ERAS Group. 
Outcome 
(sq. root) 
SD 
%Reduction 
Group 
Difference 
Power 
BESB N 
ERAS N 
48 hr OME 
0.26 
15% 
0.16 
80% 
32 
64 
48 hr OME 
0.26 
15% 
0.16 
85% 
36 
72 
48 hr OME 
0.26 
20% 
0.21 
80% 
19 
38 
48 hr OME 
0.26 
20% 
0.21 
85% 
21 
42 
96 hr OME 
0.32 
15% 
0.18 
80% 
38 
76 
96 hr OME 
0.32 
15% 
0.18 
85% 
43 
86 
96 hr OME 
0.32 
20% 
0.25 
80% 
20 
40 
96 hr OME 
0.32 
20% 
0.25 
85% 
23 
46 
 
Table 2.  Background Data 
Group N Obs Variable 
N Mean Std Dev Median 
ERAS 
20 sqD0N0D1N1 
sqtotalome 
D0N0D1N1_OME 
Total_OME 
20 
20 
20 
20 
1.050 
1.231 
1.134 
1.557 
0.181 
0.211 
0.390 
0.540 
1.049 
1.227 
1.100 
1.505 
BESB 
10 sqD0N0D1N1 
sqtotalome 
D0N0D1N1_OME 
Total_OME 
10 
10 
10 
10 
0.890 
1.120 
0.854 
1.346 
0.261 
0.320 
0.528 
0.724 
0.898 
1.157 
0.810 
1.340 
 
Given the possibility of patient withdrawal due to procedural changes, 
intraoperative exclusionary events, etc., we plan to enroll 45 patients for the BESB 
intervention group and 90 matched historical controls from the cardiac ERAS 
database (IRB P00029161). 
 
M.  Study Organization 


Drs. Roland Brusseau, Nathalie Roy, and Morgan Brown will serve as principal 
investigators. Patient screening, recruitment, enrollment, and data collection will 
be performed by a designated member of the research team. 
  
N.  Potential Benefits 
It is possible that, as a result of receiving these blocks, a patient might a) be exposed 
to less narcotic and benzodiazepine than might otherwise be the case, b) be 
extubated sooner and as such be at less risk for ventilator-associated pneumonia, 
and/or c) mobilize earlier and therefore avoid numerous possible postoperative 
complications. These are just putative benefits known to be associated with 
regional anesthetics and thus may occur in study participants.  
Results from our pilot study suggested an approximate 25% reduction in opioid 
requirements in the first 48 hours following surgery, but the study was too small to 
draw any significant conclusions. Currently no data exists to recommend these 
blocks over conventional management in congenital cardiac surgery via a median 
sternotomy.  The results of this study may allow the investigators to develop an 
appropriately powered, randomized controlled trial to evaluate the utility of this 
intervention which might be used to inform such management decisions for future 
patients. 
  
O.  Privacy Provisions 
Information will only be made available to individuals who are part of the research 
team. Medical information collected for this study will only become part of the 
child’s medical record if the information is determined to be pertinent to the care 
the child is receiving at Boston Children’s Hospital. Disclosure of personal 
information may occur only when required by law.  
  
P.  Confidentiality Provisions 
All identifying information such as dates of birth, names, and medical record 
numbers will be removed from the study database. All patients will be assigned an 
ID number that will not be linked to any patient identifying information. All data 
will be electronically secured in a password protected private folder. Only research 
investigators and personnel affiliated with the study will have access to patient 
information. 
Every effort will be made by research staff to keep patient information confidential. 
To ensure patient confidentiality, all research data will be secured in locked filing 


cabinets in a locked office. Any publications that result from this study will not be 
linked with personal identifiable information that would disclose the identity of 
study subjects. 
  
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