Assessment of the Effect of Age on Duration of Analgesia From Single-shot Femoral Nerve Blocks


Cohort study to examine the effect of age on duration of analgesia in patients receiving single-shot femoral nerve block prior to surgery, by postoperative phone follow-up questionnaire.

Study Type

  • Study Type: Observational
  • Study Design
    • Time Perspective: Prospective
  • Study Primary Completion Date: June 15, 2021

Detailed Description

The purpose of this study is to find out how differences in age can affect the duration of pain relief from a femoral nerve block. Complete recovery after leg surgery involves healing of tissues at the surgical site, recovery of muscle strength and range-of-motion. Some pain is normally experienced after leg surgery. At the hospital, pain is usually treated with pain medicines, and/or a nerve block procedure. A nerve block involves injecting a local anesthetic beside the nerves to numb the nerves that supply feeling to the knee joint and surrounding tissues. The choice as to whether a participant has a nerve block or not is made by the participant and their surgeon and is not determined by this research study. The study aim is to find out how long a nerve block can relieve postsurgical pain, and whether that duration is affected by the age of the participant.

Clinical Trial Outcome Measures

Primary Measures

  • Duration of analgesia
    • Time Frame: From time of block placement to patient to the reported end of analgesic effect, up to 72 hours
    • Total duration of analgesia from peripheral femoral nerve block

Participating in This Clinical Trial

Inclusion Criteria

  • Adult patients (age >18 years)
  • American Society of Anesthesiology physical status 1—3
  • Having ambulatory surgery, who have received a single-shot femoral nerve block
  • Able to read and understand English
  • Have access to a phone after surgery

Exclusion Criteria

  • Pediatric patients (age <18 years)
  • American Society of Anesthesiology physical status >3
  • Unable to read and understand English
  • Unable to have access to a phone after surgery

Gender Eligibility: All

Minimum Age: 18 Years

Maximum Age: N/A

Are Healthy Volunteers Accepted: Accepts Healthy Volunteers

Investigator Details

  • Lead Sponsor
    • University of Washington
  • Provider of Information About this Clinical Study
    • Principal Investigator: Vanessa Loland, Professor, School of Medicine – University of Washington
  • Overall Official(s)
    • Vanessa J Loland, MD, Principal Investigator, University of Washington
  • Overall Contact(s)
    • Adam J Claessens, DO, 206-291-7445,

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