Pain Stimulator Adam Platt Jen Wells Biz Slyziuk Kalee McFadden Bryan Eckerle March 25, 2004

Dr. Stephen Bruehl Research Interests Endogenous Pain Regulatory Systems, Psychobiology of Emotions Focus: Understanding endogenous pain regulatory systems and dysfunction associated with chronic pain. Interaction between cardiovascular and pain regulatory systems to maintain homeostasis during painful stimuli compared to interaction in chronic pain patients

Experimental Importance NIH funded 120 subjects Two research sessions one week apart Stimulation of C-fibers Placebo vs. drug Measures level of activity of receptors Draw conclusions on natural pain systems in humans

Experimental Method Automated blood pressure cuff attached to bicep of dominant arm Blood pressure cuff placed on middle finger of non-dominant hand ECG Cannula inserted into dominant arm Blood drawn to assess natural stress hormones and inflammatory substances Task Performed McGill Pain Questionnaire

Drugs to be Tested Yohimbine Naloxone Blocks 2 adrenergic receptors which inhibit release of norepinephrine Used clinically for erectile dysfunction (orally) For Dr. Bruehl’s purposes, the FDA has only approved injections Naloxone Blocks opiate receptors Used clinically for heroine overdose Injected into patient

Problems with Existing Device No electronic output Oral reading No accurate measurement of pressure Lever system with constant weight No adjustability for height or hand dominance Adjustable only for finger placement

Our Design Device Maintain lever system Most stable design Reposition weight to be placed vertically above finger Contact Point Between top two joints on index finger of dominant hand Middle Phalanx #2

Our Design… Cont. Table Transportation Positioning Adjustable Height Sliding Tracks Forearm length Slider scale mounted to table displaying “No Pain” to “Worst Pain Imaginable”

Schematic Slider Scale Device PC Computer LabVIEW A/D Converter (Pressure Transducer) PC Computer LabVIEW A/D Converter

Device with Measurements

Materials Aluminum Lucite Steel

Device Construction In process Featheringill machine shop

LabView Timer Sliding Scale Digital Display Graphical Output Audiovisuals Digital Data Storage Patient Administrator Date Experimental Data

LabVIEW Interface

Questions?