Ultrasound Guidance Versus Electrical Stimulation for Continuous Popliteal-Sciatic Nerve Blocks

University of California San Diego

Status and phase: Completed; Phase 4

Conditions: Postoperative Pain; Foot Numbness

Treatments: Procedure: Popliteal catheter placed via ultrasound or electrical stimulation

Study type: Interventional

Funder types: Other

Identifiers

NCT00876681

Popliteal Catheter: US vs. NS

Details and patient eligibility

About

Research study to determine if pain relief following foot and/or ankle surgery is influenced by the technique used to place perineural catheter. The catheters are placed using ultrasound-guidance or nerve stimulation and the method is selected at random using a computer program. This may help to determine if one of these methods is associated with an increased success rate and incidence of foot numbness during the infusion.

Full description

Specific Aim 1: To determine the relationship between perineural catheter placement technique (ultrasound-guidance and electrical stimulation) and quality of postoperative analgesia during continuous popliteal-sciatic nerve blocks following moderate-to-severely painful orthopedic surgery.

Hypothesis 1: When inserting a perineural catheter for a continuous peripheral nerve block, the use of electrical stimulation, as compared with ultrasound-guidance, is associated with decreased pain the morning following moderate-to-severely painful orthopedic surgery as measured with a numeric rating scale.

Specific Aim 2: To determine the relationship between perineural catheter placement technique (ultrasound-guidance and electrical stimulation) and degree of sensory deficit during continuous popliteal-sciatic nerve blocks following moderate-to-severely painful orthopedic surgery.

Hypothesis 2: When inserting a perineural catheter for a continuous peripheral nerve block, the use of electrical stimulation, as compared with ultrasound-guidance, is associated with increased sensory deficit the day following moderate-to-severely painful orthopedic surgery as measured with a simple 0-10 scale (0=no numbness; 10=completely insensate) of the part of the foot with the greatest sensory deficit at the time of the data-collection phone call.

Enrollment: 80 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Undergoing surgery with a planned popliteal-sciatic perineural catheter for postoperative analgesia
• Expected postoperative pain to be at least moderate in severity the day following surgery (often not adequately treatable with oral analgesics alone)
• Age 18 years or older

Exclusion criteria

• Pregnancy
• Inability to communicate wiht the investigators and hospital staff
• Incarceration
• Current chronic opioid use (daily opioid equivalent of >10mg oxycodone for more than the previous four weeks)
• History of alcohol or opioid abuse
• Neuropathy in the surgical extremity
• Any physical, mental or medical conditions which may confound quantifying postoperative pain resulting from surgery

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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80 participants in 2 patient groups

1. Ultrasound

Active Comparator group

Description:

Ultrasound method of placement is selected randomly, using a computer program. The patient is asked their pain and discomfort using a 0-10 scale where 0=no pain/discomfort and 10=worst pain/discomfort imaginable. The patient is asked this question prior to surgery, but after catheter placement and then again the first day after surgery. Time of placement is also measured and begins when the ultrasound probe first touches the skin. Patients are also asked the numbness of their foot and toes based on a 0-10 scale where 0=no numbness and 10=completely numb.

Treatment:

Procedure: Popliteal catheter placed via ultrasound or electrical stimulation

2. Electrical Stimulation

Active Comparator group

Description:

Electrical stimulation (nerve stimulation) method of placement is selected randomly, using a computer program. The patient is asked their pain and discomfort using a 0-10 scale where 0=no pain/discomfort and 10=worst pain/discomfort imaginable. The patient is asked this question prior to surgery, but after catheter placement, and then again the first day after surgery. Time of placement is also measured and begins when the nerve stimulation needle first touches the skin. Patients are also asked the numbness of their foot and toes based on a 0-10 scale where 0=no numbness and 10=completely numb.

Treatment:

Procedure: Popliteal catheter placed via ultrasound or electrical stimulation