for people ages 18-75 (full criteria)
healthy people welcome
at San Diego, California
study started
estimated completion
Alan R Hargens, PhD



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

Official Title

Skin Surface Pressures Under Blood-Draw Tourniquets


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.


Skin Pressures Under Blood Draw-tourniquets blood draw tourniquets skin surface pressure blood draw band elastic tourniquet phlebotomy tourniquet pressure Sensation and Skin Surface Pressures Under Blood-Draw Tourniquets Skin surface pressures under tourniquets and sensation


You can join if…

Open to people ages 18-75

  • 18 years or older

You CAN'T join if...

  • 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.


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

Lead Scientist

  • Alan R Hargens, PhD
    Professor, Orthopedic Surgery. Authored (or co-authored) 106 research publications


in progress, not accepting new patients
Start Date
Completion Date
University of California, San Diego
Study Type
Last Updated