Intravenous Cooling System to Induce Mild Hypothermia April 10 th, 2007 Steve Huppman Jermaine Johnson Sylvia Kang Erin Wacker University of Pittsburgh Senior Design – BioE

Cardiac Arrests On average EMS treat 107,000 – 240,000 out-of-hospital cardiac arrests per year 1 Cardiac arrest with no blood flow for a period >5 min  cerebral brain damage due to ischemia will occur In 2006, AHA estimates 163,221 out-of- hospital cardiac arrests annually in US 1 1.American Heart Association. Heart Disease and Stroke Statistics – 2006 Update

Therapeutic Hypothermia Therapeutic hypothermia in literature since 1950’s but widely ignored until 2002 ILCOR recommended unconscious cardiac arrest patients should be cooled between 32 – 34 °C for hrs 2 Cooling the body to this temperature immediately after cardiac arrest has the potential improve the neurological outcome and reduce the mortality rate 2.Nolan, JP. Morley, PT. Vanden Hoek, TL, et al. Therapeutic hypothermia after cardiac arrest: an advisory statement by the advanced life support task force of the International Liaison Committee on Resuscitation. Resuscitation. Vol. 57, No. 3, 2003

Project Objectives Design a device to induce mild hypothermia in a person that has suffered cardiac arrest no later than 5 min after blood flow has ceased Will do so by designing an IV cooling system that will attach between a saline bag and the IV injection site on the patient Device should be able to cool saline to a temperature 10 °C below room temperature for a period of 15 min Additional external cooling will occur as the device is placed on the chest of the patient

Picture Intravenous Fluid Cold Fluid to Patient Chemical Ice-Bag with Internal Tubing

Physical and Operational Characteristics Able to begin the process of inducing mild hypothermia ( °C) Disposable, portable and light weight (<2 lb.) Able to stay cold (<15°C) for 15 min Capable to function at normal room temperature (22.5°C) Placed on the top of the patient’s chest Must be

Market Size To be used by EMS and other emergency first responders to help cardiac arrest victims 107,000 – 240,000 cardiac arrests treated per year out of the hospital 3 We envision the device can be used in all emergency vehicles May also be used to help victims suffering from heat-related illness Firefighters 3.American Heart Association. Heart Disease and Stroke Statistics – 2006 Update

Competitive Analysis Celsius Control System™ by Innercool Therapies Portability And Emergency Usage Temperature Controllability Effectiveness of Cooling Price IV Cooling System √√√ Celsius Control System √√ (US Patent , Innercool Therapies, Inc, 1998)

Competitive Analysis (con’t) Cooling Body Garment Receives gaseous coolant from a supply Cooling garment applies the coolant directly to the skin of the patient As the coolant moves away from the patient, it carries the heat away, thereby cooling the patient Portability And Emergency Usage Temperature Controllability Effectiveness of Cooling Price IV Cooling System √√√ Cooling Body Garment (US Patent , Medtronic, Inc, 2003)

Competitive Analysis (con’t) Hypothermia Induction Device Recirculates blood through an extracorporeal circuit using a venous access The blood can be cooled and/or treated before reentry to the vascular system Portability And Emergency Usage Temperature Controllability Effectiveness of Cooling Price IV Cooling System √√√ Hypothermia Induction Device √√ (US Patent 2006/ , 2006)

Marketing Suggestions Big market on induction of hypothermia Many previous methods and devices have been developed on this topic Focused on either precise internal cooling or external cooling only Portable internal cooling systems used in emergency situations have been rarely studied

Theoretical Design Considerations Conservation balance for mass through a tube Test subject 160 pounds 50 liters of body fluid (water) Starting temperature of 37°C Ending temperature of 34°C Ambient conditions Room temperature of 22.5°C Ammonium nitrate solution temperature of 4°C

Want to infuse 2 liters Infused saline needs to be -40°C Infused saline enters at 10°C Need to infuse 6.3 liters This would double blood volume *Reconsider product specifications* Theoretical Design Considerations

Design Alternatives Design #1  tubing in series Standard IV tubing Saline temp 14.9°C Flow rate 0.5 ml/sec 60 mins to infuse 2 L. Minivolume IV tubing Saline temp 14.7°C Flow rate 0.1 ml/sec 300 mins to infuse 2 L. Intravenous Fluid Cold Fluid to Patient Chemical Ice-Bag with Internal Tubing *Insufficient cooling and flow rate*

Design Alternatives Design #2  tubing in parallel 32 tubes across 2 rows of 16 *Pressure drop too large*

Design Description Tubing in parallel 1 row of 16

Tubing in parallel Standard IV tubing Average saline temperature of 10°C Flow rate of 1 ml/sec  30 mins to infuse 2 L. Using the same mass conservation as before Infusing 2 liters of saline at 10°C Ammonium nitrate solution temp of 4°C Design Description *Will decrease body temp by ~1.5°C*

Engineering Technologies/Methodologies Manifold designed in SolidWorks Manufactured by hand Manifold: Dacron (6”) Tubes: PVC, size of standard IV tubing(10”) 1 Ammonium Nitrate : 2 Water*

Experimental Set Up Saline + Pressure BagHeat ExchangerPatient + Thermometer

Design Weaknesses Infusion of 2 L takes 30 mins but device is only used for 15 min Device needs to be primed  saline bag becomes a part of the device Measured average temperature of water  do not know temp at which saline is entering

Quality Systems Analysis Initial Hazard Analysis Regulation

Risk Classification Risk Classification: 4 = acceptable, 1 = unacceptable Occurrence Consequences NegligibleMarginalCriticalCatastrophic Frequent2111 Probable3211 Occasional3321 Remote4332 Improbable4433 Incredible4444

Initial Hazard Analysis Hazard Risk Class Ammonium Nitrate Entering Blood Stream Due To Entry Into Saline Line Individuals Involved: Patient 1 Skin Irritation Due To Casing Malfunction (i.e. Tear, Leakage from Seals, etc) Individuals Involved: Emergency Response Personnel Patient 3 Premature Activation of Ammonium Nitrate Individuals Involved: None 4

Regulation Class II Medical Device C Predicate Devices: CFR Title 21 – 510(k) Cooling Systems Subpart F – Part Cardiovascular Therapeutic Devices Thermal Regulation SystemClass: II Subpart F – Part Physical Medicine Therapeutic Devices Tubing, Fluid DeliveryClass: II Intravenous Tubing Subpart F – Part General Medicine Devices Pack, Hot or Cold, Disposable Class: I Pack, Hot or Cold, Water Circulating Class: II

Team Member Contributions Erin Theoretical design considerations Jermaine Literature review, FDA regulations Steve Ordering supplies, testing of prototype Sylvia Marketability, competitive analysis

Acknowledgements Thanks to The generous gift of Drs. Hal Wrigley and Linda Baker Department of Bioengineering Our mentor, Dr. James Menegazzi Andy Holmes Dr. Jack Patzer II Dr. Mark Gartner

Questions?