Sensation and Skin Pressures Under Blood-Draw Tourniquets

Skin Surface Pressures Under Blood-Draw Tourniquets

Purpose: This research study seeks to determine whether surface pressures generated by elastic tourniquets used by phlebotomists during blood-draws can penetrate to deeper tissues where major arteries and nerves lie. Additionally, investigators will also determine the effects of prolonged tourniquet application on hand sensation using a controlled, reproducible force stimulus. In conjunction, the investigators will also track changes in skin surface pressures and pain levels over this prolonged tourniquet application. Hypothesis: The investigators hypothesize the use of common elastic tourniquets used for blood draws does not significantly impact sensation and will not elicit nerve or tissue damage. Technologies used: Monofilaments and Pressure Sensor

Study Overview

• Status: Completed
• Conditions: Skin Pressures Under Blood Draw-tourniquets
• Intervention / Treatment: Other: Sensation and Skin Surface Pressures Under Blood-Draw Tourniquets

Detailed Description

The objective of this study is to investigate the reproducibility and consequently the safety of common elastic tourniquet methods for blood draws. Specifically, the study will investigate whether the surface pressures produced by blood draw tourniquets when applied by experienced phlebotomists are significant enough to penetrate to deeper tissue near bone where major arteries and nerves lie. By relating factors including tourniquet width and patient arm circumference to our surface pressure measurements and comparing our results to previous literature, the investigators hope to determine the safety of current blood draw tourniquet procedures.

In addition, the investigators will track changes in skin surface pressures over time to determine if prolonged exposure to these tourniquet pressures has the potential to permanently affect nerve function and muscle in tissues near bone.

Hand sensation will be investigated during a prolonged tourniquet application trial of the study to test the effects of the generated pressures on median, ulnar, and radial nerve viability over time.

• Study Type: Interventional
• Enrollment (Actual): 10
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • San Diego, California, United States, 92103
      • UC San Diego Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• 18 years or older

Exclusion Criteria:

• no history of abnormal heart conditions
• no history of coagulation disorders
• will not be on prescription medications that affect cardiovascular system (ex: medications that affect blood pressure or cardiac contractility etc.)**

• does not have diabetes

  • Types of medications that affect the cardiovascular system and are part of the exclusion criteria include but are not limited to: anticoagulants, antiaginals, antiarrhythmic agents, anti-hypertensive/hypotensive agents, cardenolides, cardiac stimulants, hypolipidemic agents, inotropic agents, vasoconstrictors, as well as vasodilators.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Skin surface pressures under tourniquets and sensation; Phase 1: Each phlebotomist will apply the tourniquet 10 separate times to the right arm of each subject. The tourniquet will remain on the arm for approximately ten seconds, to be able to allot enough time to collect an accurate pressure measurement. All 10 tourniquet skin pressure measurements will take place on the same day for a subject. Phase 2: 20 subjects will be subjected to a prolonged blood-draw tourniquet application for a duration of 1 hour. The purpose of phase 2 is to determine whether there is an effect on sensation from prolonged blood tourniquet use.

Other: Sensation and Skin Surface Pressures Under Blood-Draw Tourniquets; Phase 1: Skin surface pressures will be recorded by an investigator during each of the 10 applications of the tourniquet. All 10 tourniquet skin pressure measurements will take place in the Blood Draw clinic at the UCSD Medical Center in Hillcrest on the same day for a subject. Phase 2: The same 20 subjects will be subjected to a prolonged blood-draw tourniquet application for a duration of 70 minutes. The purpose of phase 2 is to determine whether there is an effect on sensation from prolonged blood tourniquet use. External skin pressures will not exceed 60mmHg. During this prolonged tourniquet application the investigators will monitor changes in hand sensation at 10-minute intervals using Semmes-Weinstein monofilaments on three peripheral nerves of the hand (median, radian, and ulnar).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Skin Surface Pressure Under Blood-Draw Tourniquet with Phlebotomists (Phase 1)	The pressure under blood draw tourniquets will be taken in Phases 1 and 2. During phase 1, the tourniquet will remain on the subject for a brief period of time (10-15 seconds) 10 times, allowing for enough time to acquire pressure measurements using the PicoPress device. The difference between Phase 1 and Phase 2 is that phase 1 will be performed with a phlebotomist, while phase 2 will be performed with one of the investigators for an extended period of time.	Phase 1: 10-15 seconds (10 times within a 5 -10 minute period)
Skin Surface Pressure Under Blood-Draw Tourniquet and Change in sensation during a 1 hour period (Phase 2)	Phase 2: The PicoPress will constantly monitor pressure under the arm tourniquet for one hour. The investigators will also simultaneously monitor the changes from baseline in sensation using Semmes-Weinstein Monofilaments on the radial, ulnar, and median nerves in participants.	Phase 2: 70 minutes (sensation will be measured every 10 minutes)

Collaborators and Investigators

• Sponsor: University of California, San Diego
• Investigators: Principal Investigator: Alan R Hargens, PhD, UCSD

Publications and helpful links

General Publications

• Crenshaw AG, Hargens AR, Gershuni DH, Rydevik B. Wide tourniquet cuffs more effective at lower inflation pressures. Acta Orthop Scand. 1988 Aug;59(4):447-51. doi: 10.3109/17453678809149401.
• Partsch H, Mosti G. Comparison of three portable instruments to measure compression pressure. Int Angiol. 2010 Oct;29(5):426-30.

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2016
• Primary Completion (Actual): October 1, 2018
• Study Completion (Actual): October 1, 2018

Study Registration Dates

• First Submitted: June 9, 2017
• First Submitted That Met QC Criteria: June 13, 2017
• First Posted (Actual): June 14, 2017

Study Record Updates

• Last Update Posted (Actual): February 7, 2020
• Last Update Submitted That Met QC Criteria: February 5, 2020
• Last Verified: February 1, 2020

More Information

Terms related to this study

• Keywords: phlebotomy; tourniquet pressure; blood draw tourniquets; skin surface pressure; blood draw band; elastic tourniquet
• Other Study ID Numbers: 161885

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual Participant Data will not be shared.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No