Study Measuring Total Plasma Ropivacaine Levels During Continuous Peripheral Nerve Catheter Infusion

The purpose of the study is to measure the blood levels of the medicine called ropivacaine (local anesthetic) used to manage pain. Ropivacaine is a widely used medication and is not the subject of this study, but the investigators are studying how much of the drug can be found in the patient's blood, known as the blood level, of this medicine. Too much ropivacaine in a patient's blood can lead to local anesthetic toxicity. Once the nerve catheter is removed, local anesthetic toxicity is no longer a potential problem. However, there is little data on what ropivacaine blood levels are after having the catheter in for a long period of time(up to one month).

Study Overview

• Status: Completed
• Conditions: Anesthesia

• Study Type: Observational
• Enrollment (Actual): 49

Contacts and Locations

Study Locations

• United States
  • Maryland
    • Bethesda, Maryland, United States, 20889
      • Walter Reed National Military Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 89 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Military health care beneficiaries age 18 years and older presenting for upper or lower extremity surgery requiring continuous infusions of local anesthetic either at WRNMMC will be asked to participate in the study. We will recruit up to fifty patients for the study at WRNMMC.

Description

Inclusion Criteria:

• Males and females 18 years and older, capable of providing informed consent indicating awareness of the investigational nature of the study, in keeping with institutional policy
• Written informed consent must be obtained from each patient prior to entering the study
• Patients must be scheduled to receive a continuous peripheral nerve catheter

Exclusion Criteria:

• Refusal to have serial blood drawn
• Contraindication for a continuous peripheral nerve catheter (allergy to local anesthetic, infection at site of injection, elevated coagulation times (international normalized ratio (INR)>1.5, partial thromboplastin time (PTT)>38; these values are drawn as part of routine standard of care and those values will be checked prior to initial catheter insertion), therapeutic dosing of anticoagulation medication, moderate to severe head injury and moderate to severe traumatic brain injury
• Patients with a hematocrit < 20. Complete Blood Counts (CBCs) are drawn as part of routine standard of care and will be followed by the Acute Pain Service. Although the CBCs and ropivacaine blood draws will not always coincide, we will always check the last hematocrit obtained prior to our blood draw
• Severe liver or renal disease (values greater than two times normal range)

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Plasma Ropivicaine Levels	Blood will be drawn every 0, 3, 5, 7, and 10 days. Blood is drawn every 3 days thereafter.	up to 10 days

Collaborators and Investigators

• Sponsor: Defense and Veterans Center for Integrative Pain Management

Study record dates

Study Major Dates

• Study Start: April 1, 2010
• Primary Completion (Actual): November 1, 2011
• Study Completion (Actual): November 1, 2011

Study Registration Dates

• First Submitted: October 17, 2012
• First Submitted That Met QC Criteria: October 29, 2012
• First Posted (Estimate): October 31, 2012

Study Record Updates

• Last Update Posted (Actual): August 12, 2019
• Last Update Submitted That Met QC Criteria: August 9, 2019
• Last Verified: August 1, 2019

More Information

Terms related to this study

• Keywords: Ropivacaine Level; continuous peripheral nerve blocks.
• Other Study ID Numbers: 353368-19