Intralipid® 20% for Reversal of Local Anesthetics

NCT03968822 | Active Not Recruiting Phase 4 FDA Drug

• 1 other identifier: 2018-2039
• Study Type: interventional
• Target: 18
• Locations: 1 country
• Sites: 1

Brief Summary

In order to determine if Intralipid 20% can be used to reverse the effects of local anesthetics, the investigators will recruit 18 volunteers who will be asked to come to HSS for two study visits. Small amounts of local anesthetics will be injected into the volunteers' thighs during both visits. During one visit volunteers will receive Intralipid 20% and during the other visit they will receive a saline solution. The study team will measure how quickly normal sensation returns to the thighs when the volunteers get Intralipid 20% compared to saline.

Conditions

Anesthesia, Local

Outcome Measures

Primary Outcomes (4)

• Time to complete normal sensation after lidocaine 1%

  The time (measured in minutes) when the participant reports normal sensation of both cold swab and pinprick at the injection site of lidocaine 1%. Although measured for each individual participant, the average time across all participants is reported.

  up to 24 hours

• Time to complete normal sensation after lidocaine 2%

  The time (measured in minutes) when the participant reports normal sensation of both cold swab and pinprick at the injection site of lidocaine 2%. Although measured for each individual participant, the average time across all participants is reported.

  up to 24 hours

• Time to complete normal sensation after Bupivacaine 0.5%

  The time (measured in minutes) when the participant reports normal sensation of both cold swab and pinprick at the injection site of Bupivacaine 0.5%. Although measured for each individual participant, the average time across all participants is reported.

  up to 24 hours

• Time to complete normal sensation after Bupivacaine 0.25%

  The time (measured in minutes) when the participant reports normal sensation of both cold swab and pinprick at the injection site of Bupivacaine 0.25%. Although measured for each individual participant, the average time across all participants is reported.

  up to 24 hours

Secondary Outcomes (8)

• Time to normal cold swab sensation after lidocaine 1%

  up to 24 hours

• Time to normal pinprick sensation after lidocaine 1%

  up to 24 hours

• Time to normal cold swab sensation after lidocaine 2%

  up to 24 hours

• Time to normal pin prick sensation after lidocaine 2%

  up to 24 hours

• Time to normal pinprick sensation after Bupivacaine 0.5%

  up to 24 hours

Study Arms (2)

Intralipid 20% IV Bolus

EXPERIMENTAL

This is 1 out of the 2 study visits. The patient will receive 6 injections (3 in each thigh). The 6 injections are: 1. lidocaine 1% 2. lidocaine 2% 3. bupivacaine 0.5% 4. bupivacaine 0.25% 5. saline 6. no injection Each test solution will be injected over 5 seconds through a 27G needle and tuberculin syringe at a 30 degree angle. The patient will also receive an intravenous bolus in the arm of Intralipid 20%. Participant will be blindfolded for these activities so they will not know what they received during the visit.

Drug: Lidocaine 2%; Drug: Lidocaine 1%; Drug: Bupivacaine 0.25%; Drug: Bupivacaine 0.5%; Drug: Intralipid, 20% Intravenous; Other: Saline

Saline

PLACEBO COMPARATOR

This is 2 out of the 2 study visits. The patient will receive 6 injections (3 in each thigh). The 6 injections are: 1. lidocaine 1% 2. lidocaine 2% 3. bupivacaine 0.5% 4. bupivacaine 0.25% 5. saline 6. no injection Each test solution will be injected over 5 seconds through a 27G needle and tuberculin syringe at a 30 degree angle. The patient will also receive an intravenous bolus in the arm of Saline. Participant will be blindfolded for these activities so they will not know what they received during the visit.

Drug: Lidocaine 2%; Drug: Lidocaine 1%; Drug: Bupivacaine 0.25%; Drug: Bupivacaine 0.5%; Other: Saline intravenously; Other: Saline

Interventions

Lidocaine 2% DRUG

3 mL of test solution to a skin area on the thigh, 2cm in diameter

Also known as: Lidocaine Viscous, Lidoderm, Recticare

Intralipid 20% IV Bolus; Saline

Lidocaine 1% DRUG

3 mL of test solution to a skin area on the thigh, 2cm in diameter

Also known as: Lidocaine Viscous, Lidoderm, Recticare

Intralipid 20% IV Bolus; Saline

Bupivacaine 0.25% DRUG

3 mL of test solution to a skin area on the thigh, 2cm in diameter

Also known as: Marcaine, Sensorcaine

Intralipid 20% IV Bolus; Saline

Bupivacaine 0.5% DRUG

3 mL of test solution to a skin area on the thigh, 2cm in diameter

Also known as: Marcaine, Sensorcaine

Intralipid 20% IV Bolus; Saline

Intralipid, 20% Intravenous DRUG

a 250ml bag administered intravenously

Also known as: i.v. fat emulsion

Intralipid 20% IV Bolus

Saline intravenously OTHER

a 250ml bag administered intravenously

Also known as: salt

Saline

Saline OTHER

3 mL of test solution to a skin area on the thigh, 2cm in diameter

Also known as: salt

Intralipid 20% IV Bolus; Saline

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• English speaking
• BMI 18-25, with body weight between 50-100kg

You may not qualify if:

• ASA III or higher
• Pregnant Women
• Allergy to study medications (lidocaine, bupivacaine, soybeans, eggs)
• Use of drugs affecting the sensorium (including opioids, benzodiazepines, antipsychotics, gabapentinoids)

Sponsors & Collaborators

• Hospital for Special Surgery, New York: lead

Study Sites (1)

Hospital of Special Surgery

New York, New York, 10021, United States

Location

MeSH Terms

Interventions

Lidocaine; Lidoderm; Bupivacaine; soybean oil, phospholipid emulsion; Salts; Sodium Chloride

Intervention Hierarchy (Ancestors)

Acetanilides; Anilides; Amides; Organic Chemicals; Aniline Compounds; Amines; Inorganic Chemicals; Chlorides; Hydrochloric Acid; Chlorine Compounds; Sodium Compounds

Study Officials

• Stavros Memtsoudis, MD/PhD

  Hospital for Special Surgery, New York

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Masking Details: Patients will be blinded to which treatment they are receiving both times they come in for the study.
• Purpose: OTHER
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 21, 2019
• First Posted: May 30, 2019
• Study Start: July 26, 2019
• Primary Completion (Estimated): October 1, 2026
• Study Completion (Estimated): October 1, 2026
• Last Updated: December 8, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL
• Time Frame: Beginning 9 months and ending 36 months following article publication
• Access Criteria: Investigators whose proposed use of the data has been approved by an independent review committee identified for this purpose. For individual participant meta-analysis. Proposals may be submitted up to 36 months following article publication. After 36 months the data will be available in our data warehouse but without investigator support other than deposited metadata.

Locations

US (1)