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Comparison of Ultrasound and Nerve Stimulation Technique for Continuous Sciatic Nerve Block

This study has been completed.
National Board of Health, Denmark
Information provided by:
University of Aarhus Identifier:
First received: July 4, 2007
Last updated: December 18, 2009
Last verified: December 2009

The most useful method to manage pain after major foot and ankle surgery is infusion of local anesthetic with a catheter close to the sciatic nerve in the popliteal space above the knee joint.

Inaccurate catheter placement and spread of local anesthetic account for most failures.

The most prevalent method to place the catheter is the traditional nerve stimulation technique relying on surface anatomic landmarks and electrical stimulation to localize the sciatic nerve. In recent years ultrasound technique has been applied to provide real-time, visual guidance of catheter placement.

The purpose of this randomized, controlled trial is to compare the success rate, patient acceptance and cost-effectiveness of the ultrasound and nerve stimulation techniques.

Condition Intervention
Procedure: placement of popliteal catheter

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: A Prospective, Randomized Comparison of Ultrasound Versus Nerve Stimulation Guidance of Popliteal, Sciatic Catheter Placement After Major Foot and Ankle Surgery: Clinical Outcome and Cost Analysis

Resource links provided by NLM:

Further study details as provided by University of Aarhus:

Primary Outcome Measures:
  • Success rate: post-operative analgesia [ Time Frame: First two post-operative days ]

Secondary Outcome Measures:
  • Time consumption of catheter placement [ Time Frame: Before surgery ]
  • Duration of post-operative observation [ Time Frame: After surgery ]
  • Pain score [ Time Frame: First two post-operative days ]
  • Nausea score [ Time Frame: First two post-operative days ]
  • Sensory block [ Time Frame: First two post-operative days ]
  • Patient acceptance [ Time Frame: First two postoperative days ]
  • Cost-effectiveness [ Time Frame: Two days ]

Enrollment: 100
Study Start Date: August 2007
Study Completion Date: October 2009
Primary Completion Date: October 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: I
Ultrasound guided placement of popliteal catheter
Procedure: placement of popliteal catheter
Bolus naropin 7,5 mg/ml 30 ml; infusion bupivacaine 2,5 mg/ml 5-10 ml/h
Experimental: II
Nerve stimulation guided placement of popliteal catheter
Procedure: placement of popliteal catheter
Bolus naropin 7,5 mg/ml 30 ml; infusion bupivacaine 2,5 mg/ml 5-10 ml/h

Detailed Description:

Foot and ankle surgery is typically very painful for the first two days postoperatively due to surgical oedema. This pain is difficult to control with systemic analgesics. Pain relief with systemic analgesics requires high doses of intravenous opioids and is associated with breakthrough pain and adverse effects of opioids (sedation, nausea, vomiting, obstipation, urinary retention, mouth dryness, respiratory depression, pruritus, vertigo and visual disturbances).

Single-shot technique provides analgesia for two to 30 hours even using analgesics with prolonged effect (bupivacaine, levobupivacaine, ropivacaine). The duration of the block depends on the local analgesic and the anatomical location. Popliteal block with bupivacaine last up to 24 hours. Continuous, peripheral nerve block with catheter technique for two days minimizes the need for systemic analgesics and their adverse effects. Continuous, peripheral nerve block has gained popularity for foot and ankle surgery, because better analgesia is obtained compared to intravenous opioids, and similar analgesia with fewer adverse effects compared to epidural catheter technique.

Today the nerve stimulation technique is the most prevalent technique to introduce catheters for peripheral nerve blocks. The success rate for postoperative analgesia after foot and ankle surgery with popliteal catheters is variable - typically 70% in our department. The patients with catheter failure have severe postoperative pain, high opioid dosages, cognitive blurring, nausea, vomiting, reduced ambulation, increased surgical stress response and increased morbidity. Pain problems and adverse effects prolongs postoperative observation time and maybe also time to discharge.

Ultrasound technique was employed for peripheral nerve blocks for the first time in 1978. However the utility was technically limited. In recent years, the evolution of high-frequency transducers and mobile ultrasound units have facilitated the application of ultrasound-guided peripheral nerve blocks. This technique allows dynamic visualization of nerves, needle tip location and spread of local analgesic in real-time.

The empirical basis supporting the theoretical advantages of ultrasound-guided regional anesthesia consists mainly of observational studies. A few, randomized, controlled trials comparing ultrasound- and nerve stimulation technique favour the benefit of ultrasound concerning success rate, sensory onset time, duration of block, patient satisfaction and quality of block.

The purpose of this study is to establish whether ultrasound technique has higher success rate, better patient satisfaction and higher cost-effectiveness compared to electrical nerve stimulation using popliteal, sciatic catheters for postoperative analgesia after foot and ankle surgery.


Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

elective posterior foot and/or ankle surgery

  • calcaneus osteotomy
  • subtalar arthrodesis
  • total ankle arthroplasty
  • ankle arthrodesis (non-arthroscopic) minimum age 18 years ASA I-III informed consent

Exclusion Criteria:

  • coagulation disorders
  • infection in the region of needle insertion
  • systemic infection
  • preoperative sciatic nerve neuropathy
  • preoperative motor or sensory deficit in the operative extremity
  • Charcot-Marie-Tooth disorder
  • diabetic neuropathy
  • severe peripheral vascular disease
  • allergy to local anesthetics
  • lack of understanding of the visual analogue scale
  • communication problems
  • dementia
  • body mass index above 35
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00497276

Department of Anesthesiology, Aarhus University Hospital
Aarhus, Denmark, DK-8000 Aarhus C
Sponsors and Collaborators
University of Aarhus
National Board of Health, Denmark
Principal Investigator: Thomas F Bendtsen, Ph.d. Department of Anesthesiology, Aarhus University Hospital, Norrebrogade, DK-8000 Aarhus C, Denmark
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Danish Centre for Health Technology Assessment (DACEHTA) Identifier: NCT00497276     History of Changes
Other Study ID Numbers: 0-204-03-8/27
Study First Received: July 4, 2007
Last Updated: December 18, 2009

Keywords provided by University of Aarhus:
Anesthesia recovery period
Comparative study
Electric stimulation
Nerve blocks/methods/indications
Patient satisfaction
Peripheral nerves
Sciatic nerve/ultrasonography
Treatment outcome
Nerve blocks/economics processed this record on March 28, 2017