Use of Ultrasound Guidance to Assist With Labor Epidural Placement in Patients With a BMI ≥40
Phase: NA
Conditions: Labor Pain
Sponsor: Thomas J. Vernon

Use of Ultrasound to Assist with Labor Epidural Placement in Patients with a BMI ≥40 
 
 
 
 
Use of Ultrasound Guidance to Assist with Labor Epidural 
Placement in Patients with a BMI ≥ 40 
 
NCT02984267  
 
Date: 10/1/2016 
 
 

Use of Ultrasound to Assist with Labor Epidural Placement in Patients with a BMI ≥40 
 
Research Protocol Abstract: 
 
Placement of labor epidurals is a very common daily practice in obstetrical anesthesia. 
Currently, these epidurals are placed based upon palpation of landmarks to determine 
midline and the correct spinal level for placement. Palpation of these landmarks can be 
difficult, however, particularly in morbidly obese patients who have significant amounts of 
soft tissue overlying these landmarks which can contribute to an increased number of 
attempts needed for placement, increased time required to complete the procedure, 
increased likelihood for complications, and decreased patient satisfaction. In recent years, 
ultrasound guidance has been increasing in popularity as a way to help visualize the spine 
and offset these challenges, though there is a lack of data comparing its practical 
application for daily use against the current standard of a palpation based only technique. 
 
Objectives: 
The objective of this study is to determine if ultrasound guidance can be utilized in morbidly 
obese patients to improve the total time required for epidural placement, decrease the 
number of attempts needed, increase the success rate in the first attempt, decrease the 
complication rate, and lead to improved patient comfort and satisfaction levels. 
 
Study Design: 
Prospective, multicenter (MWH and West Penn Hospital) randomized controlled trial 
 
Setting/Participants: 
This study will be limited to inpatient laboring patients presenting to Magee Women’s 
Hospital of UPMC and to West Penn Hospital and desiring epidural anesthesia for anticipated 
vaginal delivery. Inclusion criteria include BMI ≥ 40, Age ≥ 18, and ASA 
classification score of 3. Exclusion criteria include contraindications to neuraxial 
blockade, previous lumbar surgery, intrauterine fetal demise, non-viable fetus, or known 
scoliosis. 
 
Study Interventions and Measures: 
The major intervention in this study is the use of ultrasound (US) guidance to assess for 
correct spinal location prior to epidural placement. This differs from the current standard of 
care which is to use palpation only to assess for correct spinal location. The outcome 
measures that will be assessed and evaluated include: 
• Total time required for epidural placement* 
• Epidural procedure time** 
• Number of epidural attempts needed 
• Success rate in the first attempt 
• Complication rate including incidence of PDPH and paresthesias 
• Incidence of failed epidurals needing to be replaced 
• Verbalized patient anxiety and satisfaction levels based on a 1-10 scale 
• Modified Woman’s Views of Birth Labour Satisfaction Questionnaire (WOMBLSQ) scores 
*Procedure time plus the time needed to locate the puncture site using either palpation or 
ultrasound guidance, begins when hands or ultrasound probe are applied to the patient 
**Time from insertion of the epidural needle to removal of the epidural needle  
 
 

Use of Ultrasound to Assist with Labor Epidural Placement in Patients with a BMI ≥40 
 
Describe the availability of resources and the adequacy of the 
facilities to conduct this study: 
* The facilities and resources as they currently exist are perfectly 
adequate for this study. This study involves performing epidurals on 
laboring inpatients at Magee Women's Hospital which is already routinely 
done many times every day. All of the supplies and resources necessary 
are already present. The study also involves using an ultrasound machine 
to evaluate the patient's spine prior to performing the epidural. Such an 
ultrasound machine is already owned by the anesthesia department and 
resides on the labor and delivery floor to be used to help with epidurals 
and other various procedures. We have every ability to use this machine 
for this study at no additional costs to the patients, anesthesia 
department, or hospital. Everything we need, we already own and are 
able to use. No additional resources, expenses, or charges will be needed 
as a result of this study. 
 
 
Objective: What is the overall purpose of this research study? (Limit response to 1- 
2 sentences.) 
The objectives of this study are to assess if using ultrasound imaging to identify the 
epidural space prior to epidural placement in morbidly obese patients improves results over 
a palpation based technique alone in regards to: 
• Epidural procedure time 
• Total time 
• Number of attempts 
• Success rate in the first attempt 
• Number of failed epidurals 
• Complications including post dural puncture headache (PDPH) or paresthesias 
• Patient anxiety and satisfaction levels 
 
Specific Aims: List the goals of the proposed study (e.g., describe the relevant 
hypotheses or the specific problems or issues that will be addressed by the 
study). 
Primary Objective (or Aim) 
The primary objective of this study is to determine if using ultrasound guidance for epidural 
catheter placement is associated with a reduction in the total time required in epidural 
catheter placement. 
Secondary Objectives (or Aim) 
The secondary objectives are to further determine if using ultrasound guidance for epidural 
placement: 
• Decreases the number of attempts 
• Increases the success rate in the first attempt 
• Decreases the number of failed epidurals 
• Leads to fewer complications including PDPH or paresthesias 
• Improves patient satisfaction and anxiety levels 
 
Background: Briefly describe previous findings or observations that provide the 
background leading to this proposal. 

Use of Ultrasound to Assist with Labor Epidural Placement in Patients with a BMI ≥40 
 
Placement of labor epidurals is a very common daily practice in obstetrical anesthesia. 
Currently, these epidurals are placed based upon palpation of landmarks to determine 
midline and the correct spinal level for placement. Palpation of these landmarks can be 
difficult, however, particularly in morbidly obese patients who have significant amounts of 
soft tissue overlying these landmarks which can contribute to an increased number of 
attempts needed for placement, increased time required to complete the procedure, 
increased likelihood for complications, and decreased patient satisfaction. In recent years, 
ultrasound guidance has been increasing in popularity as a way to help visualize the spine 
and offset these challenges. 
Ultrasound guidance is already used in multiple patient populations to assist with many 
different procedures including neuraxial and peripheral nerve blocks. With regards to 
peripheral nerve blocks, it is now considered standard of care to use ultrasound guidance to 
provide visualization when performing nearly any procedure including interscalene blocks, 
supraclavicular blocks, infraclavicular blocks, axillary blocks, femoral nerve blocks, sciatic 
nerve blocks, adductor canal blocks, quadratus lumborum blocks, transversus abdominus 
plane blocks, and others. It is also standard in anesthesiology to use ultrasound guidance to 
assist with central line placement such as internal jugular or femoral vein central lines. 
Multiple centers have also begun using it for neuraxial placement such as with epidurals, 
spinals, or combined spinal epidurals (CSEs). Several researchers such as Carvalho, Vallejo, 
Chin, Balki, Ansari, and others have explored the use of ultrasound guidance in obstetric 
patients and found it useful in several ways such as estimating the distance to and more 
easily locating the epidural space. We hope to continue to expand the current research in 
this area. 
There have been no attempts to date at West Penn Hospital to begin enrolling patients for 
this study. This was due to the PI (myself) no longer being available at that facility to 
conduct the research. The PI at that location has since been changed to Tracey Vogel and 
they intend to begin data collection within the next month. 
 
Significance: Why is it important that this research be conducted? What gaps in 
existing information or knowledge is this research intended to fill? 
Several studies have looked into the use of ultrasound guidance to assist with placing labor 
epidurals. It has been demonstrated that ultrasound guidance can help to identify the depth 
from the surface of the skin to the epidural space thus aiding in epidural placement. Further 
studies have demonstrated the use of ultrasound guidance in identifying the correct spinal 
level for epidural placement and in helping to provide more reliable landmarks for 
placement of the epidural needle. Studies have also been conducted on the use of 
ultrasound in patients with easily palpable spines and reports of using it in patients that are 
known to be difficult. Ultrasound use has even been shown to improve complications such 
as decreasing the failed labor epidural rate in resident trainees. 
Despite these studies demonstrating clinical benefits to the use of ultrasound guidance, 
there have been no studies directly comparing the two methods with a focus on the 
practical aspects of overall time to perform the procedure, complication rate, and patient 
satisfaction in morbidly obese parturients. By comparing the use of ultrasound guidance to 
the current standard of palpation only, we hope to provide evidence that the use of 
ultrasound in morbidly obese patients provides not just an experimental but also practical 
advantage over palpation alone, which can then be used to promote the more routine use 
of ultrasound guidance in this patient population. 
 

Use of Ultrasound to Assist with Labor Epidural Placement in Patients with a BMI ≥40 
 
Will screening procedures (i.e., procedures to determine research subject 
eligibility) be performed specifically for the purpose of this research study? 
* Yes 
 
List the screening procedures that will be performed for the purpose of this 
research study.  
Obese patients will have their medical records screened for eligibility. Additional information 
for screening will be obtained by history and physical examination which is a routine part of 
clinical anesthesia care on the labor and delivery unit. Information to be gleaned include BMI 
and any relevant associated medical conditions which may be a contraindication to epidural 
placement. After this initial conversation, should the patient be eligible, the study will be 
introduced in its entirety as explained elsewhere in this protocol. 
 
Provide a detailed description of all research activities (e.g., all drugs or devices; 
psychosocial interventions or measures) that will be performed for the purpose of 
this research study. 
This description of activities should be complete and of sufficient detail to permit 
an assessment of associated risks. 
At a minimum the description should include: 
all research activities 
personnel (by role) performing the procedures 
location of procedures 
duration of procedures 
timeline of study procedures 
This study is to be a prospective, randomized, controlled trial of morbidly obese parturients 
presenting to either West Penn Hospital or Magee Women’s Hospital for delivery and 
desiring epidural anesthesia. Patients will be screened for participation in the study during 
the standard pre-anesthesia assessment that is already conducted by anesthesia staff on all 
patients presenting to Labor and Delivery. Screening will include an evaluation of the 
patient’s medical history and BMI. The study will then be explained to patients who satisfy 
the inclusion and exclusion criteria and informed consent obtained should they choose to 
participate. A waiting period of 5-30 minutes will elapse between introduction of the study 
to the participant's consent to participate. At the time the patient is ready to receive their 
epidural, an opaque, sealed, numeric envelope labeled only with a study number will be 
opened containing the data collection sheet and randomly assigned group for that 
participant. These envelopes will be prepared prior to beginning the study by a healthcare 
provider not involved in the study. An online randomizer (Randomization.org) will be used 
to generate a random order for assignment to either the ultrasound guidance group 
(experimental group) or the palpation only group (control group) which will be revealed to 
the experimenters only upon opening the envelope at the time of epidural request. These 
envelopes will be distributed in equal numbers to each facility participating in the study at 
the onset of the study. 
Once the patient has progressed in their labor to the point where they request placement of 
labor epidural analgesia, the primary investigator for that site (Thomas Vernon at Magee, 
and Tracey Vogel and West Penn) will be the one to open the envelope revealing which 
group the patient has been assigned to. This will occur during the same hospitalization as 
the screening visit and in many cases within just a matter of minutes to hours after the 
initial screening and consent process. This same person will then position the patient in 

Use of Ultrasound to Assist with Labor Epidural Placement in Patients with a BMI ≥40 
 
their labor and delivery room appropriately for their epidural and then use either the 
ultrasound machine (experimental group) or palpation (control group) to mark with a 
marking pen the desired location for epidural placement. Thomas Vernon and Tracy Vogel 
will be the only providers to mark the patients. Every attempt will be made for them to be 
available for study patients, but if they cannot be (they are caring for another patient or are 
no longer in the hospital at the time the epidural is requested) then the patient may have 
to be dropped from the study. Once the patient has been marked, a second anesthesia 
provider who will be performing the epidural will come into the room. This second provider 
will be blinded to whether the marks on the patient were made based upon ultrasound 
guidance or palpation (the patient will not be blinded). This second provider who will 
perform the epidural can be any type of experienced provider (attending, fellow, resident, 
or CRNA) who has already completed at least 40 epidurals in the past. They will then 
perform the epidural in the standard fashion, using the previously marked site as their 
initial entry point. If entering at the already marked site does not result in success, the 
provider performing the procedure may reassess and redirect at their discretion. During 
epidural placement, the primary investigator (Thomas Vernon or Tracy Vogel) will be 
responsible for timing the procedure and recording the number of attempts required to 
succeed. Epidurals are typically placed successfully within 5-10 minutes depending on 
patient anatomy and provider experience. 
Following the epidural placement and achievement of pain relief, the patient will be asked 
to rate their satisfaction and anxiety levels during the procedure. No extra interventions or 
monitoring specific to this study (i.e. outside of what is already normally performed) will be 
required. 
Patients will be followed up on in their hospital room within 24 hours of their delivery to 
assess for any complications related to their epidural placement and to administer the 
modified WOMBLSQ questionnaire. If a complication is detected, treatment will be given as 
clinically warranted. Following that visit no further participation from the patient will be 
necessary. This study is projected to take about 6 months to complete. 
 
Will follow-up procedures be performed specifically for research purposes? 
Follow-up procedures may include phone calls, interviews, biomedical tests or 
other monitoring procedures. 
* Yes 
Detailed procedures listed in the textbox below: 
Following the epidural placement the patient will be asked to rate their satisfaction and 
anxiety levels during the procedure. The patient will again be followed up with in their 
hospital room within 24 hours of their delivery to assess for any complications related to 
their epidural placement and to administer the modified WOMBLSQ questionnaire. Following 
that visit no further participation from the patient is anticipated. Should they present 
afterwards with an epidural-related complication, that information will be collected and 
included in the study.