The Impact of a Preoperative Nerve Block in Foot and Ankle Surgery on the Consumption of Sevoflurane

NCT04022057 | Withdrawn Phase 2

• 1 other identifier: Pro00092857
• Study Type: interventional
• Target: N/A
• Locations: 1 country
• Sites: 1

Brief Summary

Reconstructive foot and ankle surgery is performed under general anesthesia. Included in this spectrum of surgery are ankle arthroplasties, various fusions, corrective arthrodesis, and more. Pain control for after the surgery can be achieved purely with intravenous and oral pain medication or in combination with freezing of the nerves. Nerve freezing (nerve block) placed before surgery has the potential to substantially reduce the amount of inhaled anesthetic given to the patient during surgery. This can benefit the patient with being more awake and crisp more quickly after surgery. It can also reduce cost to the system. A further benefit which has received very little attention so far, is that reducing the amount of inhaled anesthetic given also lowers the environmental footprint created by the anesthetic. For the region of the foot and ankle to be fully frozen, both the sciatic nerve and the saphenous nerve must be successfully blocked. Sciatic nerve blockade is most commonly achieved by blocking the nerve in the popliteal fossa. This block is named popliteal nerve block. The investigators will examine and quantify the amount of inhaled anesthetic used for each case and will compare how the consumption is affected by whether the nerve blocks are applied before or after surgery. Patients will have two nerve block catheters (popliteal and saphenous catheter) placed under ultrasound-guidance prior to the case by an experienced and specifically trained anesthesiologist. The catheters will be loaded with a solution to which the anesthesiologist is blinded. It will either be local anesthetic or 5% dextrose (sham). The general anesthetic will be conducted according to a research protocol with anesthetic depth being the targeted endpoint. Measurements of the required MAC-Value (minimum alveolar concentration) of inhaled anesthetic will be recorded every five minutes by a study team member. At the end of the case the anesthesiologist will be unblinded to the solution. Should the patient have received sham initially, they will now receive the full dose of local anesthetic prior to being woken up.

Conditions

Ankle Arthropathy; Anesthesia; Functional; Ankle Arthritis

Outcome Measures

Primary Outcomes (1)

• Age-adjusted MAC of sevoflurane per hour

  The average age-adjusted end- tidal minimum alveolar concentration (MAC) will be calculated by averaging the end tidal MAC required to maintain the depth of anesthesia as measured by PSI between 25-50 intra-operatively. This will be compared between the two groups.

  Intraoperative measurement done at the end of anesthetic

Secondary Outcomes (10)

• Intraoperative heart rate

  Intraoperative period

• Intraoperative opioid use

  Intraoperative period

• Postoperative opioid use in PACU

  Up to 24 postoperative hours

• Maximum pain scores in the first 24 post-operative hours

  Up to 24 postoperative hours

• Nausea and vomiting in the first 24 post-operative hours

  Up to 24 postoperative hours

Study Arms (2)

Pre-GA

ACTIVE COMPARATOR

10 mL of 1% ropivacaine injection before the start of surgery and 10 ml of 5% dextrose injection at the end of surgery through both the popliteal and the saphenous catheter

Drug: Ropivacaine injection; Drug: Dextrose 5

Post-GA

SHAM COMPARATOR

10 mL of 5% dextrose injection before the start of surgery and 10 ml of 1% ropivacaine injection at the end of surgery through both the popliteal and the saphenous catheter

Drug: Ropivacaine injection; Drug: Dextrose 5

Interventions

Ropivacaine injection DRUG

Local anesthetic injection

Post-GA; Pre-GA

Dextrose 5 DRUG

Sham Injection

Post-GA; Pre-GA

Eligibility Criteria

• Age: 18 Years+
• Gender Eligibility Details: All gender identification and self-representation is accepted
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients undergoing elective reconstructive foot and ankle surgery
• Patients eligible for popliteal and saphenous nerve block
• All adults 18 years of age or older
• Capable to give consent

You may not qualify if:

• Patients who are unable to give consent
• Local anaesthetic allergy
• Hemidiaphragm paresis on the contralateral side to the block/surgery site
• Bleeding diathesis
• Coagulopathy
• Pre-existing neurological deficits
• Patients with a Body Mass Index \>35
• Patients with significant comorbidities, physiological limitations, and allergies that are unable to tolerate the protocolized induction and maintenance of anesthesia.

Sponsors & Collaborators

• University of Alberta: lead

Study Sites (1)

University of Alberta Hospital

Edmonton, Alberta, T6G2G3, Canada

Location

MeSH Terms

Interventions

Ropivacaine

Intervention Hierarchy (Ancestors)

Anilides; Amides; Organic Chemicals; Aniline Compounds; Amines

Study Officials

• Vivian HY Ip, MD

  University of Alberta

  STUDY DIRECTOR

• Lora Pencheva, MD

  University of Alberta

  STUDY DIRECTOR

• Rakesh V Sondekoppam, MD

  University of Alberta

  STUDY CHAIR

• Timur JP Özelsel, MD, DESA

  University of Alberta

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Double-blinded, randomized controlled, prospective

Study Record Dates

• First Submitted: July 8, 2019
• First Posted: July 16, 2019
• Study Start: August 1, 2019
• Primary Completion: March 15, 2020
• Study Completion: March 15, 2020
• Last Updated: June 6, 2024

Record last verified: 2024-06

Locations

CA (1)