Saphenous Nerve Block: Single Shot Versus Continuous Infusion to Supplement a Continuous Sciatic Nerve Block After Major Ankle Surgery

Major Ankle Surgery Clinical Trial

Official title:

A Randomized Comparison of Single Injection vs. Continuous Saphenous Nerve Block to Supplement a Continuous Sciatic Nerve Block in Postoperative Pain Treatment After Major Ankle Surgery: Clinical Outcome and Cost Analysis

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01445210
• Other study ID #: 2011-0184
• Status: Completed
• Phase: N/A
• First received: September 29, 2011
• Last updated: October 18, 2012
• Start date: September 2011
• Est. completion date: October 2012

Study information

• Verified date: October 2012
• Source: University of Aarhus
• Contact: n/a
• Is FDA regulated: No
• Health authority: Denmark: Danish Dataprotection Agency
• Study type: Interventional

Clinical Trial Summary

The most useful method to manage pain after major ankle surgery is infusion of local analgesics with a catheter close to the sciatic nerve.

Sensation from the ankle are carried by three nerves: The tibial and peroneal nerve (unified in the sciatic nerve) and the saphenous nerve.

Study purpose is to test whether continuous infusion of local analgesics by saphenous nerve catheter provide a better treatment of pain in comparison with a single injection nerve block. In addition cost-effectiveness of the two methods are compared.

The 50 patients of the trial are randomized in clusters of ten. We intend to do a preliminary analysis of the data from the first 40 patients. However, it is not an interim analysis. Fifty patients will be included independent of the result of the preliminary analysis. The random allocation of the last 10 patients will also be double-blinded.

Description:

Major ankle surgery are known to be very painful the first 48 hours after the operation 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, respiratory depression).

Continuous, peripheral nerve block with catheter technique for two days minimizes the need for systemic analgesics. Today such a continuous sciatic nerve block is part of the standard pain treatment after major ankle surgery on Aarhus University Hospital. Despite accurate placement of the catheter many patients are in great pain because the saphenous nerve remain unaffected. A single injection block relieve the pain but a block with Ropivacaine only last 8-15 hours.

Severe postoperative pain leads to 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.

The aim of the study establish whether continuous saphenous nerve block is efficient (pain relief or reduced opioid consumption) and justified (cost-effectiveness analysis) compared with single injection block.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 50
• Est. completion date: October 2012
• Est. primary completion date: October 2012
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years and older

Eligibility

Inclusion Criteria: Elective major ankle surgery

• total ankle arthroplasty

• subtalar fusion

• ankle fusion (non arthroscopic)

Exclusion Criteria:

• coagulation abnormalities

• infection in the region of needle insertion

• systemic infection

• preoperative consumption of high dose opioid

• preoperative sciatic or femoral nerve neuropathy

• preoperative sensory deficit in either of the lower extremities

• Charcot-Marie-Tooth disorder

• diabetic neuropathy

• severe peripheral vascular disease

• allergy to local anesthetics

• lack of understanding of Numeric Rank Scale (NRS)

• communication problems

• dementia

• body mass index above 35

• bilateral continuous sciatic nerve block

• lack of consent

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Major Ankle Surgery

Intervention

Procedure:
• Continuous saphenous nerve block
0,2% Ropivacaine by elastomeric infusion pump at 5 ml/h for 48 postoperative hours
• Placebo
Isoton saline by elastomeric infusion pump at 5 ml/h for 48 postoperative hours

Locations

Country	Name	City	State
Denmark	Aarhus University Hospital	Aarhus

Sponsors (2)

Lead Sponsor	Collaborator
University of Aarhus	Aarhus University Hospital

Country where clinical trial is conducted

Denmark, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Accumulated opioid consumption		First 48 hours postoperative	No
Secondary	Success rate for saphenous nerve analgesia	Pain rated by NRS and opioid consumption	Postoperative, first 48 hours	No
Secondary	Success rate for clinical analgesia of foot and ankle	Pain rated by NRS and opioid consumption	Postoperative, first 48 hours	No
Secondary	Success rate for tibial and peroneal nerve block	Pain rated by NRS and test of sensation on the toes	Postoperative, first 48 hours	No
Secondary	Localisation of worst pain		Postoperative, first 48 hours	No
Secondary	Cost-effectiveness		2 first postoperative days	No