Comparing Ways to Freeze the Nerve That Provides Thigh Sensation

• Status: Completed
• Trial end date: 2016-06-01
• Target enrollment: 0
• Participant gender: All

Summary

Background

The sensation on the outside of portion of our thighs is provided by a nerve called the lateral femoral cutaneous nerve (LFCN). The investigators can inject freezing around the nerve to reduce the feeling around the thigh (i.e. anesthesia). Anesthesia, or freezing, of the lateral femoral cutaneous nerve can reduce pain for patients having A) hip and knee surgery [1,2], B) removal of a skin graft [3], and C) wound care. In addition, damage to the LFCN (i.e. Meralgia Paresthetica) has been associated with body armour and gun belt use in military and police personnel [4]. Although generally a benign condition, compression or injury to this nerve can be painful and require treatment. In addition, the actual variability in sensory distribution for this nerve has not been elucidated in a topographical fashion and will be measured in this study.

Finding the most efficient and effective method for anesthesia of the LFCN can improve and positively impact the quality of pain control for patients. Ultrasound has improved the accuracy and efficiency of various other regional anesthesia techniques, and could also impact the safety. Therefore the investigators hypothesize that ultrasound guided lateral femoral cutaneous nerve block using the subinguinal technique will be statistically more efficacious and efficient when compare to neurostimulation based blockade.

• Phase: Phase 3
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: Canadian Forces Health Services Centre Ottawa
• Treatments: Anesthetics; Anesthetics, Local; Lidocaine

Criteria

Inclusion Criteria:

• male and female between 18 and 60 years old

• American Society of Anesthesiologists classification 1-3

Exclusion Criteria:

• adults who are unable to give their own consent

• pre-existing neuropathy (assessed by history and physical examination) -

• coagulopathy (assessed by history and physical examination and, if deemed clinically necessary, by blood work up i.e. platelets ≤ 100, International Normalized Ratio ≥ 1.4 or prothrombin time ≥ 50)

• renal failure (assessed by history and physical examination and, if deemed clinically necessary, by blood work up i.e. creatinine ≥ 100)

• hepatic failure (assessed by history and physical examination and, if deemed clinically necessary, by blood work up i.e. transaminases ≥ 100)

• allergy to local anesthetic agents local anesthetic

• pregnancy based on patient self report of last menstrual cycle. If a patient wish/insist on participating in the study, and pregnancy status is unclear, a urine pregnancy test will be offered. Also risk of Lidocaine in pregnancy will be discussed with the patient as currently classified. We will convey that this risk is currently classified as a Risk Class B, which means that animal-reproduction studies have not demonstrated a fetal risk but there are no controlled studies in pregnant women. We will also discuss that animal-reproduction studies have shown an decrease in maternal fertility), but that was not confirmed in controlled studies in women in the first trimester and there is no evidence of a risk in later trimesters,

• prior surgery in the hip and lateral leg region

• prior lumbar surgery

• previous pelvic fracture

• previous L1, L2 or L3 lumbar radiculopathy, plexopathy or meralgia paresthetica

• chronic pain syndromes requiring opioid intake