Clinical trial NCT01167907
Conditions: Orthopedic Surgery of Lower Extremity
Keywords: ankle arthrodesis internal fixation bi/tri malleolar fracture
Sponsor: Wake Forest University Health Sciences
Start date: 2010-07-01; Completion date: 2017-09-07
Enrollment: 32 participants; Allocation: RANDOMIZED; Intervention model: PARALLEL

Brief summary:
A nerve block catheter is a small tube placed next to a nerve through a needle, and the needle is then removed. Numbing medicine is dripped through the tube to reduce pain sensation from the nerve.

The purpose of this research study is to test whether the placement of a second nerve block catheter, rather than a single injection for the saphenous nerve block will improve pain relief and/or reduce pain medication needed after surgery enough to justify two nerve block catheters.

There are two nerves that carry pain sensations from the ankle, the large (sciatic) nerve and the smaller (saphenous) nerve. Patients undergoing ankle fusion or fracture surgery at Wake Forest University typically have a nerve block catheter placed next to the sciatic nerve to give local anesthetic (numbing medicine) for 24-72 hours. In addition, a single injection of local anesthetic is usually performed to block the saphenous nerve for 12-16 hours postoperatively.

Detailed description:
Interventions and Interactions Study participants will be asked to report a preoperative baseline pain score (Numeric Pain Scale (0-10)), and have quadriceps strength measured (see below) prior to any sedation being administered. Patients will undergo placement of a continuous subgluteal sciatic nerve catheter, and dosage with 25ml of 0.25% bupivacaine with epinephrine 1:200,000 and clonidine 25 mcg per usual technique after sedation. A perineural catheter will then be placed for primary saphenous nerve block and postoperative saphenous infusion. This continuous saphenous catheter will be placed using ultrasound guidance (Sonosite Turbo ™, Bothell, WA) (6-13MHz linear probe). The superficial femoral artery will be identified in short axis at approximately the midpoint or distal third of the femur as the artery lies deep to the sartorius muscle in the adductor canal. Using aseptic technique, an 18 gauge tuohy needle will be inserted in-plane from lateral to the transducer and advanced to a position anteromedial to the artery, between sartorius and vastus medialis muscles. Proper positioning will be confirmed by injection of saline, a 20g multiorifice catheter will be inserted 3-4 cm beyond the needle tip and the catheter will be tunneled and taped up the medial surface of the thigh. The catheter will be test dosed with 1.5% lidocaine with 1:200,000epinephrine to confirm position and rule out IV injection. The primary saphenous nerve block will be produced by incremental injection through the catheter of 10ml of 0.25% bupivacaine with epinephrine 1:200,000 and clonidine 15 mcg. Successful saphenous block will be defined as loss of sensation to pinprick in the mid, anteromedial leg measured at 15 and 30 minutes post-block. A 3-point scale will be used to define sensory block: 0=full sensation, 1= touch without sharp sensation, 2=absent sensation.

To determine the effect of saphenous block on quadriceps function, patients will have knee extension muscle strength tested pre-block and 30 min post-block using a Hoggan Health microFET 2 MT Digital Handheld Dynamometer. After placement of both the saphenous and sciatic nerve catheters, patients will receive either neuraxial or general anesthesia for surgical anesthesia at the discretion of the attending anesthesiologist medically directing their primary anesthetic technique.

Patients with evidence of sciatic and saphenous nerve block will be randomized to receive a postoperative continuous infusion of either saline (control) or 0.2% ropivacaine by elastomeric infusion pump at 5ml/h started within 6h of catheter placement. The randomization will occur by sealed envelope provided to the OR Pharmacy (block randomization in blocks of 10) and the OR pharmacy will prepare the 300 ml elastomeric pump with active or control solution. The On-Q C-Bloc™(300ml capacity) (I-Flow corporation) pump will be attached to the saphenous catheter in the PACU, or within 6h of primary block; the catheter will infuse for 60 hours.

The patients, physicians, nurses and investigators will be blinded to treatment group.

The sciatic infusion will be managed per usual practice: postoperatively all patients will receive 0.2% ropivacaine through their sciatic nerve catheter at a basal infusion rate of 10ml/h, . The sciatic pump will be an On-Q™ pump per usual practice. All patients will have oral and IV opioids prescribed while hospitalized, and oral opioids prescribed after hospital discharge. In the event of breakthrough pain, patients will be instructed to adjust the sciatic nerve pump, and/or to take oral opioids for the pain.

While patients are hospitalized, opioid administration and pain scores will be recorded by nursing staff on the patient care record. Side effects including nausea, vomiting, or itching will also be recorded. Patients will be seen on a daily basis while in the hospital by the acute pain service, and adjustment of their sciatic infusion performed if indicated. They will be questioned about sleep quality, pain score, opioid side effects, and sensory function in the sciatic and saphenous distributions. This information will be recorded by the acute pain management team. On postoperative day 1, all patients will again have their quadriceps muscle group strength assessed with the hand-held dynamometer, and the catheter sites will be inspected per standard protocol.

Patients will be generally discharged home with peripheral nerve catheters in place on POD #1, after receiving written and verbal instructions in perineural catheter management. These patients will be called at 24 and 48 hours post discharge to determine rest and incident numeric pain scores, opioid usage, sleep quality (as number of awakenings for pain), and the presence of nausea or vomiting. Patients will be given contact numbers and instructions to call with any questions or concerns per usual practice.

Outcome Measure(s) The primary endpoint of this study will be a reduction of the rest and incident verbal pain scores 48hpost-nerve blockade when the primary saphenous single-shot block is expected to have resolved. Secondary endpoints of reduction of opioid use, nausea and vomiting, sleep disturbance (as number of awakenings), and reduction of quadriceps strength will also be evaluated.

Arms: arm 1: Patients with evidence of sciatic and saphenous nerve block will be randomized to receive a postoperative continuous infusion of either saline (control) or 0.2% ropivacaine by elastomeric infusion pump at 5ml/h started within 6h of catheter placement. arm 2: Patients with evidence of sciatic and saphenous nerve block will be randomized to receive a postoperative continuous infusion of either saline (control) or 0.2% ropivacaine by elastomeric infusion pump at 5ml/h started within 6h of catheter placement.
Interventions: intervention 1: 0.2% ropivacaine intervention 2: saline
Intervention descriptions: intervention 1: 0.2% ropivacaine by elastomeric infusion pump at 5ml/h started within 6h of catheter placement intervention 2: saline (control) by elastomeric infusion pump at 5ml/h started within 6h of catheter placement

Protocol documents:
Prot_SAP_000.pdf: 
Protocol version: 9/30/2010 
1 
 
 
NCT01167907    
 
 WFUHS 00013823 
 
PROTOCOL 
 
Evaluation of Continuous Saphenous Nerve Block to Supplement a Continuous 
Sciatic Nerve Block After Ankle Surgery 
September 30, 2010 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 


Protocol version: 9/30/2010 
2 
 
 
Study Title: Evaluation of a Continuous Saphenous Nerve Block to Supplement a Continuous 
Sciatic Nerve Block for Postoperative Analgesia Following Ankle Surgery 
 
Principal Investigator:  Robert Weller MD  
Co-investigator(s):  Daryl Henshaw MD 
 
Sponsor or funding source: Department of Anesthesiology at Wake Forest University Baptist 
Hospital.  Pumps for saphenous infusion provided by I-Flow Corporation 
 
Background, Rationale and Context 
Orthopedic surgery of the lower extremity is particularly painful, and epidural analgesia 
or long-acting nerve blocks are commonly employed to reduce post-operative pain. Unilateral 
peripheral nerve blocks have advantages over epidural analgesia including: limited sympathetic 
blockade, no interference with bladder or contralateral limb function, and the ability to be 
discharged to home with a perineural catheter and pump for local anesthetic administration.¹  
Patients undergoing ankle arthrodesis or bi/tri-malleolar fracture repairs are expected to have 
pain primarily in the sciatic nerve distribution, with a lesser component of their pain emanating 
from the medial side of the lower extremity innervated by the smaller, cutaneous  saphenous 
nerve.  At our institution, pain from this surgery is typically managed with a continuous sciatic 
nerve block maintained for 48-72h, and a single-shot saphenous or femoral nerve block with 
long-acting local anesthetic to provide 12-24h of saphenous analgesia.  In spite of this aggressive 
regional analgesia approach, many patients still complain of significant pain in the postoperative 
period,and this study is designed to assess the analgesic effect of a continuous rather than single-
shot saphenous block.  We hypothesize that patients will have a clinically important reduction of 
pain score from a longer duration of saphenous nerve block provided by a continuous catheter, 
which would justify the added complexity of 2 perineural catheters 
Ultrasound guidance to facilitate placement of peripheral nerve blocks has been shown to 
improve the onset time of analgesia, increase success of the block, reduce vascular puncture and 
increase patient satisfaction.²⁻³  While various ultrasound-guided techniques for single-shot 
saphenous block have been described in the literature, currently no description of an ultrasound-
guided continuous saphenous nerve block is available.⁴  ֿ ⁹  This study will employ an ultrasound-
guided technique for continuous saphenous block and describe this technique. 
Continuous femoral nerve block is a common practice and could also be used with sciatic 
block to provide analgesia of the medial ankle instead of a saphenous block.  Continuous 
saphenous block, however, has potential advantages over an inguinal femoral nerve catheter   
including less bacterial colonization, and preservation of quadriceps motor function.¹⁰  This study 
will assess the effect of continuous saphenous block on quadriceps function. 
 
Objectives 
 
This study will evaluate the effect of adding a continuous saphenous nerve catheter to a 
continuous sciatic nerve catheter in patients undergoing ankle surgeries.  Specifically, patients 
undergoing ankle fusions or open reduction and internal fixation of bi- or tri-malleolar fractures 
will be evaluated.  The primary endpoint of this study will be the verbal pain score at rest and 
with movement at 48h post-nerve blockade.  At this point in time the primary saphenous nerve 


Protocol version: 9/30/2010 
3 
block will have resolved, and any saphenous analgesia will be due to the infused solution.  
Secondary endpoints of opioid use, nausea and vomiting, sleep disturbance, and change in 
quadriceps strength will also be evaluated.  Additionally, we will describe an ultrasound guided 
technique for placement of a continuous saphenous nerve catheter supported by cadaveric 
dissection.   
 
 
Methods and Measures 
Design 
The study will be a randomized, double-blind, placebo-controlled trial.  Patients will be 
recruited and have sciatic and saphenous perineural catheters placed as described below, 
and initial nerve blocks produced in the usual fashion.  Patients will then be randomized 
to either an active drug (local anesthetic) or a placebo (saline) infusion group at the time 
of saphenous infusion preparation by Pharmacy personnel.   
 
Setting 
All patients in the study will be undergoing non-urgent surgery at Wake Forest 
University Baptist Medical Center.  The interventions will be performed in the regional 
anesthesia area of the surgery center.  Patients will remain in the hospital at least one 
night, and once discharged, all patients will have daily follow-up by phone with the 
regional anesthesia acute pain management team. 
 
Subject selection criteria 
Patients undergoing non-urgent unilateral ankle arthrodesis or open reduction and internal 
fixation of bi/tri malleolar fractures will be recruited for the study.   
 Inclusion Criteria 
Patients will be eligible for inclusion in the study if they are between the ages of 18-
75 and are scheduled to undergo unilateral ankle arthrodesis or open reduction and 
internal fixation of bi/tri malleolar fractures at Wake Forest University Baptist 
Medical Center.  Patient must give written informed consent for anesthesia including 
continuous sciatic nerve block and saphenous block for postoperative analgesia prior 
to recruitment.    Patients must be able to comprehend the use and care of the 
catheters and infusion pump systems both in the hospital, and at once discharged 
home with verbal and written instructions   
 Exclusion Criteria 
Patients will be excluded if they have a contraindication to saphenous or sciatic nerve 
blockade (including significant coagulation abnormalities), history of opioid 
addiction, current chronic pain therapy with high-dose opioid (extended release 
opioids or > 40mg oxycodone equivalents per day), allergy to study medications, or 
failure to place a sciatic catheter.  Failure to achieve successful sciatic analgesia or a 
successful primary saphenous block will also lead to exclusion. 
 Sample Size 
74 patients will be recruited for the study and will be randomized into two groups of n 
= 37 patients each. This sample size provides power = 0.80 to allow reliable detection 
of group differences of d = 0.74 standard deviation units (approximately 1.5 points on 
a 0 -10 pain scale in our pilot data), assuming two-sided inferences held to the  = 


Protocol version: 9/30/2010 
4 
0.025 level (see stats section for details on error control). Differences smaller than 
this magnitude are unlikely to be clinically meaningful.        
 
Interventions and Interactions 
Study participants will be asked to report a preoperative baseline pain score (Numeric 
Pain Scale (0-10)), and have quadriceps strength measured (see below) prior to any sedation 
being administered.    Patients will undergo placement of a continuous subgluteal sciatic nerve 
catheter, and dosage with 25ml of 0.25% bupivacaine with epinephrine 1:200,000 and clonidine 
25 mcg per usual technique after sedation.  A perineural catheter will then be placed for primary 
saphenous nerve block and postoperative saphenous infusion.   This continuous saphenous 
catheter will be placed using ultrasound guidance (Sonosite Turbo ™, Bothell, WA) (6-13MHz 
linear probe).  The superficial femoral artery will be identified in short axis at approximately the 
midpoint or distal third of the femur as the artery lies deep to the sartorius muscle in the adductor 
canal.  Using aseptic technique, an 18 gauge tuohy needle will be inserted in-plane from lateral 
to the transducer and advanced to a position anteromedial to the artery, between sartorius and 
vastus medialis muscles.  Proper positioning will be confirmed by injection of saline, a 20g 
multiorifice catheter will be inserted 3-4 cm beyond the needle tip and the catheter will be 
tunneled and taped up the medial surface of the thigh.  The catheter will be test dosed with 1.5% 
lidocaine with 1:200,000epinephrine to confirm position and rule out IV injection.  The primary 
saphenous nerve block will be produced by incremental injection through the catheter of 10ml of 
0.25% bupivacaine with epinephrine 1:200,000 and clonidine 15 mcg.  Successful saphenous 
block will be defined as loss of sensation to pinprick in the mid, anteromedial leg measured at 15 
and 30 minutes post-block.  A 3-point scale will be used to define sensory block: 0=full 
sensation, 1= touch without sharp sensation, 2=absent sensation.   
To determine the effect of saphenous block on quadriceps function,  patients will have 
knee extension muscle strength tested pre-block and 30 min post-block using a Hoggan Health 
microFET 2 MT Digital Handheld Dynamometer.  After placement of both the saphenous and 
sciatic nerve catheters, patients will receive either neuraxial or general anesthesia for surgical 
anesthesia at the discretion of the attending anesthesiologist medically directing their primary 
anesthetic technique.   
Patients with evidence of sciatic and saphenous nerve block will be randomized to 
receive a postoperative continuous infusion of either saline (control) or 0.2% ropivacaine by 
elastomeric infusion pump at 5ml/h started within 6h of catheter placement.   The randomization 
will occur by sealed envelope provided to the OR Pharmacy (block randomization in blocks of 
10) and the OR pharmacy will prepare the 300 ml elastomeric pump with active or control 
solution.  The On-Q C-Bloc™(300ml capacity) (I-Flow corporation) pump will be attached to 
the saphenous catheter in the PACU, or within 6h of primary block; the catheter will infuse for 
60 hours.   
The patients, physicians, nurses and investigators will be blinded to treatment group. 
The sciatic infusion will be managed per usual practice:  postoperatively all patients will 
receive 0.2% ropivacaine through their sciatic nerve catheter at a basal infusion rate of 10ml/h,  .  
The sciatic pump will be an On-Q™  pump per usual practice.  All patients will have oral and IV 
opioids prescribed while hospitalized, and oral opioids prescribed after hospital discharge.   In 
the event of breakthrough pain, patients will be instructed to adjust the sciatic nerve pump, 
and/or to take oral opioids for the pain.  


Protocol version: 9/30/2010 
5 
While patients are hospitalized, opioid administration and pain scores will be recorded by 
nursing staff on the patient care record.  Side effects including nausea, vomiting, or itching will 
also be recorded.  Patients will be seen on a daily basis while in the hospital by the acute pain 
service, and adjustment of their sciatic infusion performed if indicated. They will be questioned 
about sleep quality, pain score, opioid side effects, and sensory function in the sciatic and 
saphenous distributions.  This information will be recorded by the acute pain management team.  
On postoperative day 1, all patients will again have their quadriceps muscle group strength 
assessed with the hand-held dynamometer, and the catheter sites will be inspected per standard 
protocol.  
Patients will be generally discharged home with peripheral nerve catheters in place on 
POD #1, after receiving written and verbal instructions in perineural catheter management.  
These patients will be called at 24 and 48 hours post discharge to determine rest and incident 
numeric pain scores, opioid usage, sleep quality (as number of awakenings for pain), and the 
presence of nausea or vomiting.  Patients will be given contact numbers and instructions to call 
with any questions or concerns per usual practice. 
 
Outcome Measure(s) 
The primary endpoint of this study will be a reduction of the rest and incident verbal pain scores 
48hpost-nerve blockade when the primary saphenous single-shot block is expected to have 
resolved.  Secondary endpoints of reduction of opioid use, nausea and vomiting, sleep 
disturbance (as number of awakenings), and reduction of quadriceps strength will also be 
evaluated.  Additionally, we will describe an ultrasound guided technique for placement of a 
continuous saphenous nerve catheter supported by cadaveric dissection.   
 
Analytical Plan 
All analyses will be conducted with SAS 9.2 (SAS, Inc., Cary, NC). Prior to conducting the 
primary analysis, the distributional characteristics of all variables will be considered by 
examining histograms and descriptive statistics. Where possible, all analyses will be conducted 
using the general linear model (e.g., t-test), but where necessary nonparametric equivalents will 
be conducted for pairwise comparisons (e.g., Mann-Whitney U). As a result of random 
assignment, participant characteristics are expected to be similar, but treatment group 
characteristics will be compared using descriptive statistics. The primary analysis will consist of 
a direct comparison between treatment groups at 48 hours using an independent t-test. Because 
the primary analysis consists of two comparisons (i.e., pain with rest and pain with movement), 
each comparison will be evaluated at the  = 0.025 level (i.e., holding the family to a 
conservative 5% type-I error rate). Secondary analyses will be conducted using tests appropriate 
for the level of measurement including t-tests, Mann-Whitney U (ordinal data such as number of 
awakenings), and 2 (categorical data such as presence of nausea). Statistical significance for all 
secondary comparisons will be interpreted at p < 0.05. No interim analyses will be conducted.     
Human Subjects Protection 
 
Informed Consent 
Written informed consent will be obtained from each subject.  Patients scheduled for 
elective ankle arthrodesis will be seen in the preoperative assessment clinic at North Carolina 
Baptist Hospital.  Following preoperative assessment and consent for peripheral nerve block 
for analgesia, a research clinician will meet with the patient to discuss participation in the 


Protocol version: 9/30/2010 
6 
study.  They will be informed of the purpose of the study along with the risks, benefits, and 
alternatives. Questions will be answered and consent obtained.  Patients not seen in our 
preoperative assessment clinic will be asked to participate in the study on the day of surgery 
when admitted to the Regional Anesthesia Holding Area.  A copy of the signed informed 
consent will be placed in the patient’s medical record.  All subjects may decline participation 
in the study at any time.  Informed consent and all necessary study data will be obtained prior 
to the administration of any sedative medication.   
 
 
Confidentiality and Privacy 
Confidentiality will be protected by collecting only information needed to assess study 
outcomes, minimizing to the fullest extent possible the collection of any information that 
could directly identify subjects, and maintaining all study information in a secure manner.  
To help ensure subject privacy and confidentiality, only a unique study identifier will appear 
on the data collection form.  Any collected patient identifying information corresponding to 
the unique study identifier will be maintained on a separate master log.  The master log will 
be kept secure, with access limited to designated study personnel.  Following data collection 
subject identifying information will be destroyed at the earliest opportunity, consistent with 
data validation and study design, producing an anonymous analytical data set.  Data access 
will be limited to study staff.  Data and records will be kept locked and secured, with any 
computer data password protected.  No reference to any individual participant will appear in 
reports, presentations, or publications that may arise from the study. 
 
Data and Safety Monitoring 
The principal investigator will be responsible for the overall monitoring of the data and 
safety of study participants.  The principal investigator will be assisted by other members of 
the study staff. 
 
Reporting of Unanticipated Problems, Adverse Events or Deviations 
Any unanticipated problems, serious and unexpected adverse events, deviations or protocol 
changes will be promptly reported by the principal investigator or designated member of the 
research team to the IRB and sponsor or appropriate government agency if appropriate. 
 
References 
 
1.  Ilfeld B, Morey T, Wang R, Enneking K:  Continuous Popliteal Sciatic Nerve Block 
for Postoperative Pain Control at Home.  Anesthesiology. 2002; 97:959-965 
2.  Marhofer P, Greher M, Kapral S.  Ultrasound Guidance in Regional Anesthesia. Br J 
Anaesth. 2005;94:7-17. 
3.  Perlas A, Brull R, Chan VW, McCartney CJ, Nuica A, Abbas S.  Ultrasound Guidance 
Improves The Success Of Sciatic Nerve Block At The Popliteal Fossa.  Reg Anesth Pain Med.  
2008 May-June;33(3)259-65 
4.  Gray AT, Collins AB.  Ultrasound-Guided Saphenous Nerve Block.  Reg Anesth Pain 
Med.  2003;28:148.  
5.  Horn J, Pitsch T, Salinas F, Benninger B.  Anatomic Basis to the Ultrasound-Guided 
Approach for Saphenous Nerve Blockade.  Reg Anesth Pain Med.  2009 Sept-Oct;34(5)486-89 


Protocol version: 9/30/2010 
7 
6.  Lundblad M, Kapral S, Marhofer P, Lönnqvist P.  Ultrasound-Guided Infrapatellar 
Nerve Block in Human Volunteers: Description of a Novel Technique.  B r J Anaesth.  
2006;97(5)710-14. 
7.  Tsui BC, Özelsel T.  Ultrasound-Guided Transsartorial Perifemoral Artery Approach 
for Saphenous Nerve Block.  Reg Anesth Pain Med.  2009;34:177-78.  
8.  Kirkpatrick J, Antonakakis J.  Preliminary Experience With a New Approach to 
Performing an Ultrsound-Guided Saphenous Nerve Block in the mid to Proximal Femur.  Reg 
Anesth Pain Med.  2010:35(2)222-223. 
9.  Manickam B, Perlas A, Duggan E, Brull R, Chan V, Ramlogan R.  Ultrasound Guided 
Saphenous Nerve Block.  Reg Anesth Pain Med.  2009;34(6)578-580. 
10.  López AM, Sala-Blanch X, Carrera A.  Ultrasound Guided Perivascular Saphenous 
Nerve Block at the Midthigh for Ambulatory Surgery.  Anesthesiology.  2008;109:A632. 
 
Appendix 
1. Data collection form 
2. Consent form  

ICF_001.pdf: 
 
 
 
 
 
NCT01167907 
 
WFUHS 00013823 
 
Informed Consent 
 
Evaluation of Continuous Saphenous Nerve Block to Supplement a Continuous 
Sciatic Nerve Block After Ankle Surgery 
February 28, 2013 
 


Version: February 28, 2013
Page 1
Department of Anesthesiology
Evaluation of the Addition of a Continuous Saphenous Nerve Block to Continuous Sciatic Nerve 
Block for Postoperative Analgesia Following Ankle Arthrodesis
Informed Consent Form to Participate in Research
Robert Weller M.D. Principal Investigator
Introduction
You are invited to be in a research study. Research studies are designed to gain scientific 
knowledge that may help other people in the future. You are being asked to take part in this 
study because you are having an ankle fusion or fracture surgery, and you have already 
consented to a nerve block catheter for postoperative pain relief.  A nerve block catheter is a 
small tube placed next to a nerve through a needle, and the needle is then removed.  Numbing 
medicine is dripped through the tube to reduce pain sensation from the nerve. Your participation 
is voluntary. Please take your time in making your decision as to whether or not you wish to 
participate. Ask your study doctor or the study staff to explain any words or information 
contained in this informed consent document that you do not understand. You may also discuss 
the study with your friends and family.
Why Is This Study Being Done?
There are 2 nerves carrying pain sensations from the ankle, the large (sciatic) nerve and the 
smaller (saphenous) nerve.  Patients undergoing ankle fusion or fracture surgery at Wake Forest 
University usually have a nerve block catheter placed next to the sciatic nerve to give local 
anesthetic (numbing medicine) for 24-72 hours.  In addition, a single injection of local anesthetic 
is usually performed to block the saphenous nerve for 12-16 hours postoperatively.  The purpose 
of this research study is to test whether the placement of a second nerve block catheter, rather 
than a single injection for the saphenous nerve block will improve pain relief and/or reduce pain 
medication needed after surgery enough to justify 2 nerve block catheters. 
In this study, all patients will have a saphenous nerve block catheter, and all will receive the 
standard single injection of long-acting local anesthetic through this catheter for the initial 
saphenous nerve block.  Half of the patients will then receive a local anesthetic drip and half will 
receive a saline, or placebo drip through the catheter.  A placebo is a substance, like a sugar pill, 
WFU School of Medicine 
Institutional Review Board 
IRB Number:IRB00013823
Meeting Date Approved 1/13/2016          
Version Valid Until: 1/12/2017


Version: February 28, 2013
Page 2
that is not thought to have any effect on your condition or pain. Placebos are used in research 
studies to see if the drug being studied really does have an effect.
How Many People Will Take Part in the Study?
74 people at 1 research site (Baptist Medical Center) will take part in this study.
What Is Involved in the Study?
On the day of your surgery you will be seen in the Regional Anesthesia area of the surgical 
center.  After discussion with your Anesthesia team you will be given sedation through an I.V. 
and will have the two nerve block catheters placed. One of these will be on the back of your 
upper thigh (sciatic) and the other will be on the middle of the inside of your thigh (saphenous).  
Once we determine that your nerve block catheters are working well, you will have your ankle 
surgery either under general anesthesia or with a spinal numbing medicine, depending on your 
preference and discussion with the anesthesiologist.  After the surgery is completed, your two 
nerve block catheters will be connected to two pumps that will administer numbing medications 
on the sciatic nerve, and numbing medication or a placebo on the saphenous nerve.  During your 
hospitalization you will be seen on a daily basis by the Acute Pain Service, who will manage 
your pain medications and nerve block pumps.  Most participants in the study will stay one night 
in the hospital, but your hospital stay will be up to your surgeon.  When you do go home, the 
nerve block catheters and pumps will go home with you to provide pain control medications over 
approximately the next 2 days.  The anesthesiologists on the Acute Pain Service will call you on 
a daily basis to assess how you are doing.  You will also have phone numbers to call if you have 
any questions or concerns.  The phone calls will take approximately 10 minutes each day.  
Sometime during the 3rd day after surgery, the nerve block pumps will run out and at that time 
the physician on the Acute Pain Service will direct you or a family member how to remove the 
nerve block catheters at home.  
You will be randomized into one of the study groups described below. Randomization means 
that you are put into a group by chance, like flipping a coin. You will have an equal one in two 
chance of being placed in any group.
Neither you nor the investigator will know whether you will be receiving the numbing medicine 
or the placebo through the saphenous catheter, since the medicine is so dilute it may not make 
you feel numb, even if it is producing pain relief. This is done so that a fair evaluation of results 
can be made. This information is available to the researchers if needed in an emergency.
The saphenous nerve block catheter is the focus of this study, and it will be placed as mentioned 
above after IV sedative medicines and numbing medicine injected on the inside of your thigh.   
Ultrasound will be used to place this catheter close to the saphenous nerve and the branch of the 
femoral artery next to the nerve.  Ultrasound is a medical device that uses sound waves from a 
hand-held probe to produce an image of structures in the body beneath the skin.  It has been used 
by anesthesiologists for more than a decade to help place needles and catheters close to nerves 
with less chance of blood vessel puncture than other techniques.  To be clear, our usual practice 
for surgeries such as yours is to use ultrasound to locate and numb the saphenous nerve with a 
needle and single shot of numbing medicine, but without placing a nerve block catheter.  If you 
consent to participate in this study, a saphenous catheter will be placed, and all patients will 
WFU School of Medicine 
Institutional Review Board 
IRB Number:IRB00013823
Meeting Date Approved 1/13/2016          
Version Valid Until: 1/12/2017


Version: February 28, 2013
Page 3
receive an initial dose of long acting local anesthetic before being randomized to one of the two 
groups.  This initial injection is the same dose of local anesthetic you would receive through a 
needle if you were to decline to be in the study. 
After surgery, the sciatic catheter will be connected to a pump as usual, with a constant drip of 
medicine and adjustment of the drip rate if needed.  The saphenous catheter will be connected to 
a pump with numbing medicine or placebo (saline) drip.  In addition, you will have pain 
medicine pills to take by mouth if you need them.    
 
Since the saphenous block may cause weakness of the thigh, you will also have the muscle 
strength in your thigh tested on 2 or 3 occasions.  To test your muscle strength, we will have you 
attempt to push your leg out (like kicking a soccer ball) against a small machine, called a 
dynometer, which one of the investigators will hold in their hands.  This should cause no 
discomfort and will take approximately 30 seconds.  Your muscle strength will be tested upon 
your arrival to the Regional Anesthesia holding area, after the nerve block catheters are placed, 
and again on the morning after surgery.  
To summarize the research parts of this study:  if you agree to participate, you are consenting to 
the placement of the saphenous catheter, the equal chance of either active or placebo anesthetic 
drip through this catheter for 2-3 days, and the muscle strength testing.
All study participants will be seen every morning by the Anesthesia Acute Pain Service while in 
the hospital.   Your pain will be evaluated and you will answer several questions related to your 
pain, pain medications, satisfaction, and side effects.  After you are discharged from the hospital, 
the Acute Pain Service physicians will call you at home each day to ask you these same 
questions.  Once the pumps have run out of numbing medicine, you or your family member will 
be instructed on how to remove the dressings and the catheters and how to properly dispose of 
them.  No follow up clinic or hospital visits will be needed. 
As part of this research study, ultrasound images will be taken as the saphenous nerve block 
catheter is placed.  This is being done to document the placement of the nerve block catheter.  
These images may be used for research publication or for medical education, but since they only 
show structures under the skin, you could not be identified by looking at the image.  You may 
request the recording be stopped at any time during the course of the research study. You can 
also withdraw your consent to use and disclose the ultrasound image(s) before it is used. You 
should also understand that you will not be able to inspect, review, or approve the photographs, 
videotapes, audiotapes or other media (including articles containing such) before they are used in 
this study. 
Please choose one of the following regarding the use and disclosure of the 
photograph/videotape/audiotape used in this research study:
_____ I would like the ultrasound images of me to be destroyed once their use in this study is 
finished.
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Institutional Review Board 
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____ The ultrasound images of me can be kept for use in future studies provide they are kept 
secure and any future study will be reviewed by an IRB.   I understand that I will not be able to 
inspect, review or approve their future use.
How Long Will I Be in the Study?
You will be in the study until the numbing medicine in your saphenous pump runs out, which 
should be 48-72 hours after your surgery is completed. 
You can stop participating at any time. If you decide to stop participating in the study we 
encourage you to talk to the investigators or study staff first to learn about any potential health or 
safety consequences.  If you decide to withdraw from the study early, the physician on the Acute 
Pain Service will direct you or a family member how to remove one or both of the nerve block 
catheters at home, and you would continue to take oral pain medications.  You may experience 
increased surgery-related pain after the nerve catheters are removed and the numbing medicine 
wears off. 
What Are the Risks of the Study?
Being in this study involves some risk to you. You should discuss the risk of being in this study 
with the study staff.  Nerve block catheters have been shown to provide good pain relief, but they 
also carry some risks and side effects, and as a part of the study you will receive two catheters 
rather than the usual one.  The risks include soreness, bruising or swelling at the catheter site, 
and partial or absent pain relief (failure of block), and pain when the nerve block wears off.  
Infection may occur at the catheter site, but sterile technique is used to minimize this risk.  
Rarely, irritation or injury to nerves can occur causing continued numbness or weakness for days 
or weeks (1/500 patients).  The local anesthetics (numbing medicines) can infrequently cause 
dizziness or light-headedness when absorbed into the bloodstream, but dosages will be low for 
postoperative nerve block.  Nerve blocks may produce muscle weakness and numbness – you 
must not stand on the blocked leg, and must protect your leg and foot from injury while it is still 
numb.  The saphenous nerve catheter is placed near an artery, and there is a risk of nicking this 
blood vessel and causing bleeding; the ultrasound machine is being used to minimize this risk.  
There also may be other side effects that we cannot predict. You should tell the research staff 
about all the medications, vitamins and supplements you take and any medical conditions you 
have. This may help avoid side effects, interactions and other risks.
Taking part in this research study may involve providing information that you consider 
confidential or private.  Efforts, such as coding research records, keeping research records secure 
and allowing only authorized people to have access to research records, will be made to keep 
your information safe.
Are There Benefits to Taking Part in the Study?
You may receive improved pain relief from taking part in this research study, but you may also 
not have any personal benefit. We hope the information learned from this study will benefit other 
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people in the future.
What Other Choices Are There?
You do not have to be in this study to receive treatment. You should talk to your doctor about all 
the choices you have. Instead of being in this study, you may choose to proceed with the regional 
anesthesia (numbing shot) approach that is normally used for your surgery. This would include a 
nerve block catheter on the back side of your thigh and a shot of numbing medicine on the inside 
of your thigh, but no nerve block catheter at this second location. 
Alternatively, you may choose to have no numbing shots and treat your pain with pain 
medications by mouth or in your I.V.  
What about the Use, Disclosure and Confidentiality of Health 
Information?
By taking part in this research study, your personal health information, as well as information 
that directly identifies you, may be used and disclosed.  Information that identifies you includes, 
but is not limited to, such things as your name, address, telephone number, and date of birth.  
Your personal health information includes all information about you which is collected or 
created during the study for research purposes. It also includes your personal health information 
that is related to this study and that is maintained in your medical records at this institution and at 
other places such as other hospitals and clinics where you may have received medical care.  
Examples of your personal health information include your health history, your family health 
history, how you respond to study activities or procedures, laboratory and other test results, 
medical images, photographs/videotapes/audiotapes and information from study visits, phone 
calls, surveys, and physical examinations.
Your personal health information and information that identifies you (“your health information”) 
may be given to others during and after the study. This is for reasons such as to carry out the 
study, to determine the results of the study, to make sure the study is being done correctly, to 
provide required reports and to get approval for new products.  
Some of the people, agencies and businesses that may receive and use your health information 
are the research sponsor; representatives of the sponsor assisting with the research; investigators 
at other sites who are assisting with the research; central laboratories, reading centers or analysis 
centers; the Institutional Review Board; representatives of Wake Forest University Health 
Sciences and North Carolina Baptist Hospital; representatives from government agencies such as 
the Food and Drug Administration (FDA), the Department of Health and Human Services 
(DHHS) and similar agencies in other countries. 
Some of these people, agencies and businesses may further disclose your health information. If 
disclosed by them, your health information may no longer be covered by federal or state privacy 
regulations.  Your health information may be disclosed if required by law. Your health 
information may be used to create information that does not directly identify you. This 
information may be used by other researchers. You will not be directly identified in any 
publication or presentation that may result from this study unless there are photographs or 
recorded media which are identifiable.
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If this research study involves the treatment or diagnosis of a medical condition, then 
information collected or created as part of the study may be placed in your medical record and 
discussed with individuals caring for you who are not part of the study. This will help in 
providing you with appropriate medical care.  In addition, all or part of your research related 
health information may be used or disclosed for treatment, payment, or healthcare operations 
purposes related to providing you with medical care.
When you sign this consent and authorization form you authorize or give permission for the use 
of your health information as described in the consent form. You can revoke or take away your 
authorization to use and disclose your health information at any time. You do this by sending a 
written notice to the investigator in charge of the study at the following address:
Robert Weller
Department of Anesthesiology
Medical Center Blvd.
Winston Salem, NC 27157
If you withdraw your authorization you will not be able to be in this study. If you withdraw your 
authorization, no new health information that identifies you will be gathered after that date. Your 
health information that has already been gathered may still be used and disclosed to others. This 
would be done if it were necessary for the research to be reliable. You will not have access to 
your health information that is included in the research study records until the end of the study.
Laboratory test results and other medical reports created as a result of your participation in the 
research study may be entered into the computer systems of Wake Forest University Health 
Sciences and North Carolina Baptist Hospital.  These will be kept secure, with access to this 
information limited to individuals with proper authority, but who may not be directly involved 
with this research study.
This authorization does not expire. 
What Are the Costs?
There are no costs to you for taking part in this study. All study costs, including any study 
medications and procedures related directly to the study, will be paid for by the study. Costs for 
your regular medical care, however, which are not related to this study such as the cost for sciatic 
nerve block catheter will be your own responsibility or that of your insurance.
Will You Be Paid for Participating?
You will receive no payment or other compensation for taking part in this study.
Who is Sponsoring this Study?
This study is being sponsored by The Department of Anesthesiology at Wake Forest Baptist 
Hospital, and saphenous pumps are being provided by the I-Flow Corporation and Kimberly 
Clark Health Care to help conduct this study. The researchers do not, however, hold a direct 
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Version Valid Until: 1/12/2017


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financial interest in the sponsor or the product being studied.
What Happens if You Experience an Injury or Illness as a Result of 
Participating in this Study?
Should you experience a physical injury or illness as a direct result of your participation in this 
study, Wake Forest University School of Medicine maintains limited research insurance 
coverage for the usual and customary medical fees for reasonable and necessary treatment of 
such injuries or illnesses. To the extent research insurance coverage is available under this policy 
the reasonable costs of these necessary medical services will be paid, up to a maximum of 
$25,000. Wake Forest University Baptist Medical Center holds the insurance policy for this 
coverage. It provides a maximum of $25,000 coverage for each claim and is limited to a total of 
$250,000 for all claims in any one year. The Wake Forest University School of Medicine, and 
the North Carolina Baptist Hospitals, Incorporated do not assume responsibility to pay for these 
medical services or to provide any other compensation for such injury or illness. Additional 
information may be obtained from the Medical Center’s Director of Risk and Insurance 
Management, at (336) 716-3467.
You do not give up any legal rights as a research participant by signing this consent form. For 
more information on medical treatment for research related injuries or to report a study related 
illness, adverse event, or injury you should call Robert Weller at (336) 718-4498 or after hours 
by paging (336) 806-9414. 
What Are My Rights as a Research Study Participant?
Taking part in this study is voluntary. You may choose not to take part or you may leave the 
study at any time. Refusing to participate or leaving the study will not result in any penalty or 
loss of benefits to which you are entitled. If you decide to stop participating in the study we 
encourage you to talk to the investigators or study staff first to learn about any potential health or 
safety consequences. The investigators also have the right to stop your participation in the study 
at any time. This could be because it is in your best medical interest, your condition worsened, 
new information becomes available, you had an unexpected reaction, your nerve block catheter 
stops working, you failed to follow instructions, or because the entire study has been stopped. 
You will be given any new information we become aware of that would affect your willingness 
to continue to participate in the study.
WHOM DO I CALL IF I HAVE QUESTIONS OR PROBLEMS?
For questions about the study or in the event of a research-related injury, contact the study 
investigator, Robert Weller at (336) 718-4498 or after hours by calling the hospital operator at 
(336) 716-2011. 
The Institutional Review Board (IRB) is a group of people who review the research to protect 
your rights. If you have a question about your rights as a research participant, you should contact 
the Chairman of the IRB at (336) 716-4542.
You will be given a signed copy of this consent form. 
WFU School of Medicine 
Institutional Review Board 
IRB Number:IRB00013823
Meeting Date Approved 1/13/2016          
Version Valid Until: 1/12/2017


Version: February 28, 2013
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Signatures
I agree to take part in this study. I authorize the use and disclosure of my health information as 
described in this consent and authorization form.  If I have not already received a copy of the 
Privacy Notice, I may request one or one will be made available to me.  I have had a chance to 
ask questions about being in this study and have those questions answered.   By signing this 
consent and authorization form, I am not releasing or agreeing to release the investigator, the 
sponsor, the institution or its agents from liability for negligence.
_____________________________________________________
Subject Name (Printed)
_____________________________________________________
____________________
Subject Signature
Date / Time
_____________________________________________________
____________________
Person Obtaining Consent
Date / Time
WFU School of Medicine 
Institutional Review Board 
IRB Number:IRB00013823
Meeting Date Approved 1/13/2016          
Version Valid Until: 1/12/2017