Design of a Malignant Hyperthermia Susceptibility Screening Device Sara Doll Lisa Kaczmarski Philip Magcalas Department of Anesthesiology Children’s Hospital of Pittsburgh University of Pittsburgh Senior Design – BioE1160

Overview Malignant Hyperthermia (MH) is a chain reaction event wherein susceptible patients, when administered common gas anesthetics, undergo drastic temperature elevation. There are currently no standard devices or procedures in common practice to screen the general population for this condition. The solution lies in the design of a device that measures the isometric force produced by the thumb when the ulnar nerve is stimulated. Such a device would be beneficial to: Anesthesiologists Patients And their families

Project Goals 1.Establish a clear fundamental understanding of the effects of MH on muscle fatigue 2.Create a device design which comfortably accommodates the patient, while allowing for measurement of a solely isometric contraction force 3.Create a device design which would allow accurate measurements and clear methods of interpretation 4.Test and assess the effectiveness of the device in measuring forces within a specific range 5.Complete all of the above on a limited budget

Device Features & Benefits Arm restraint platform Firmly restrain patient’s forearm, hand, and thumb in a comfortable manner for all morphological body types Force sensor Accurately and safely measure contraction force of thumb Overall Maintain simplicity for ease of assembly, use, and data interpretation Support Adjustable mounting assembly that can be tightly secured during testing

Proposed Design

Other possible solutions… Arm restraint platform Adjustable straps Adjustable restraint ‘walls’ Interchangeable polymer thumb ‘molds’ Fixed metal ring with velcro strap Cushioned plastic Laminated wood Force sensor Strain gage Force transducer connected to metal ring Support Vises Bed-mount

Competitors Our Strengths Our Weaknesses Compared to Dr. Hoyer’s Device Simple Design Friendly User Interface Accessible Lacking years of research No previous clinical testing Time constraints Compared to Caffeine Halothane Contracture Test Non-invasive Less expensive Usable for general population Potentially less accurate No previous clinical testing Time constraints

Collaborations Universitat Wurzburg, Germany Andreas Hoyer, M.D. Melanie Veeser, M.D. Children’s Hospital of Pittsburgh Dr. Robert Sclabassi, M.D., Ph.D. Neurologist, Professor in Departments of Neurological Surgery, Psychiatry, Neuroscience, Electrical Engineering, Mechanical Engineering and Bioengineering Dr. Barbara Brandom, M.D. Anesthesiologist, Director of North American MH Registry, Professor of Anesthesiology

Technology SolidWorks - Mechanical component design National Instruments’ LabView - Circuitry design Swanson Center for Product Innovation - Prototypes, Final Product

Assumptions About Resources People Robert J. Sclabassi, M.D., Ph.D. Barbara Brandom, M.D. Andreas Hoyer, M.D. Mingui Sun, Ph.D. & George Stetten, M.D., Ph.D. Software Labview - B69 SolidWorks - B62 Locations Benedum Design Lab - B62 BioE Instrumentation Lab - B69 Children's Hospital of Pittsburgh Manufacturing Swanson Center for Product Innovation Pitt Machining Shop Product Assistance Component part companies SolidWorks instructors But most importantly! Time Money

Schedule December - Preliminary SolidWorks drawing for arm board, support - Preliminary circuitry design - Order force transducer (Grass – model FT03) January - Gather materials for prototype - Build initial prototype February - Prototype testing - Design revisions - Finalize SolidWorks drawing - Order final materials March - Build/Assemble device April - Device testing, as time allows - Draft final report and presentation

Who will be accountable for what Group Member Milestone Sara- Prototype - Component manufacturer research - Final SolidWorks drawing Phil- Preliminary device schematic - Final Device Testing/Calibration report - Final product Lisa- Preliminary SolidWorks drawing - Prototype Testing Report - Final product

Current Status General MH research Initial project meetings with mentor Project planning/development -Objective Tree -Function-Means Analysis -Human Factors testing plan -Goals, schedule, and milestones defined (Gantt chart) -Device specifications defined -Preliminary Design Schematic Observation of Dr. Hoyer’s device in use

Acknowledgements Robert J. Sclabassi, M.D., Ph.D. Barbara Brandom, M.D. Andreas Hoyer, M.D.

This is MH: =-( This is MH with our device: =) …Any Questions?