Presented by: Eric Hunter and Caitlyn Crowley Effects of Salted ice bags on surface and intramuscular cooling and rewarming rates Presented by: Eric Hunter and Caitlyn Crowley

Literature review Cryotherapy is used among healthcare providers to treat acute injuries by reducing pain and limiting the formation of swelling. 1,2 Lowers the metabolic rate decreasing the amount of oxygen needed. No optimal temperature has been set to effectively limit the negative effects of inflammation.3,4 Colder the tissues the better….. No benefit found below 5°C. 4 5*C no additional benefit was detected

Literature review Ice bags have been shown to be the most effective at cooling tissue when compared to other packs (gel, chemical). 5,6, 7 They cool intra-muscular temperature the fastest and get the coldest. Skin/intramuscular tissue continue cooling longer after the modality has been removed Skin/intramuscular tissue take longer to re-warm to normal temperature Wetted Ice bags are the most effective at decreasing skin and intramuscular temperature when compared with normal cubed or crushed ice bags. 3 Continued research has looked at most effective ways to cool tissues. No one has looked at adding salt to an ice bag

Theory Using knowledge of basic science Adding salt to H2O decreases freezing points Pilot study has demonstrated ability to decrease water temperature by adding salt Questions for audience Have you ever wondered why some people put salt in water before boiling it? What about why they put salt on the roads in the winter time?

Pilot data Control Condition: 2000 mL wetted ice  0.5 C Experimental Conditions: 2000 mL ice + uniodized salt Amount of Salt Added Resultant Temperature 1/2 cup ~ -15o C 1/4 cup ~ -11o C 1/8 cup ~ -8o C 1/16 cup (1 Tbsp) ~ -5o C

Why important to AT Field Decreased tissue temperature Decrease effects of secondary hypoxic injury Potentially decreased treatment times Faster numbing (less cold pain) Better patient compliance if treatment doesn’t take as long? Potentially longer re-warming time Secondary hypoxic injury is reduced for a longer time May result in less time loss from injury

Study design Independent variable Repeated-measures Time Counterbalanced ABC, ACB, BCA, BAC, CAB, CBA Three treatment groups Wetted cubed ice (A) Current best practice Salted cubed ice (B) Salted crushed ice (C) Independent variable Time Group Dependent variable Temperature Skin Intramuscular

Participants 24 subjects Exclusion Criteria No known vascular disease in lower leg No injury to lower leg in the last month or during the study No sensitivity to cold Not allergic to cold/ice No compromised circulation of the lower leg 18-26 Healthy Male and Female

recruitment Fliers Tear offs QR Scan Announcements in class

Measurement tools Skinfold calipers Surface thermocouple Skyndex, Cadwell, Justiss and Co, Inc., Fayetteville, AR Surface thermocouple SST-1, Physitemp Instruments, Inc, Clifton, NJ OR Omega thermocouples 26-gauge hypodermic needle microprobe Physitemp MT-26/4, Physitemp Instruments, Inc, Clifton, NJ Microprocessor thermometer Model HH23, Omega Engineering, Inc, Stamfort, CT)

conditions Wetted ice bag Salted crushed ice bag Salted cubed ice bag Cramer ice bag 2000 mL cubed ice 300 mL room temperature water Salted crushed ice bag 1 Tbsp Morton Unionized Salt 2000 mL crushed ice Salted cubed ice bag 1 Tbs Morton Uniodized Salt

Anticipated Procedures Training on insertion at BYU by Dr. David Draper & colleagues Calf measurements taken to determine location of largest girth where microprobe will be inserted on the posterior lateral portion of the calf. Skinfold measurements will be taken 3 times and then the average will be used Divide mean measurement by 2 for amount of subcutaneous fat For intramuscular depth measure a vertical distance of 2 cm plus the ½ mean skinfold Mark the lateral aspect of the lateral head of the gastrocnemius using a fabricated template labeled to the nearest millimeter to ensure proper insertion point Insertion of microprobe and placement of surface thermocouple on participants by the same two researchers

Anticipated Procedures Insertion area will be shave and cleaned prior to insertion Baseline period of 20 minutes for intramuscular temperatures to reach plateau (participants lying prone on table for entire process) Ice condition applied Treatment time of 20 minutes Ice removed Recovery time of 45 minutes Surface thermocouple, treatment template and microprobe will be removed Area will be cleaned and covered with a self-adhesive bandage ** Temperatures will recorded every 30 seconds throughout the study

Timeline Spring semester 2013 Subject recruitment period Training in microprobe insertion techniques Secure funding Subject recruitment period Beginning September 2013 Data collection period September - November 2013 Data analysis period November 2013 Prepared to defend/prepare manuscript for publication!! Spring 2014

Statistical analysis Repeated measure ANOVA Skin temperature Baseline, 30-second intervals for 20-minute treatment time, 30-second intervals for 45 minute rewarming period Intramuscular temperature Microprocessor thermometer will be video recorded to ensure accurate temperature capture at desired intervals we are doing each DV separately b/c with only 24 subjects, we do not have the power to do a multivariate analysis ANOVA in general will compare several groups (and in this case, several time periods) and tell you if there is a difference overall. it will also tell you if there is a significant difference at each time period...all wihle maintaining the familywise (overall) type I error rate at 0.05 (your p-value

Null Hypotheses There will be no difference in surface and intramuscular cooling and rewarming rates between the three treatment conditions.

Research Hypotheses Both salted crushed/cubed will decrease skin temperature more than wetted ice Both salted crushed/cubed will decrease intramuscular temperature more than wetted ice Both salted crushed/cubed will have longer skin temperature rewarming times than wetted ice Both salted crushed/cubed will have longer intramuscular temperature rewarming times than wetted ice Salted cubed ice will decrease skin temperature more than salted crushed ice Salted cubed ice will decrease intramuscular temperature more than salted crushed ice

Challenges/limitations Ice bag falling off Template on skin Limited rewarming time Initial/exploratory study

Funding NATA grant $1,000 University grant Moyes Academic Support & Technology Endowment Committee Funds used for Microprobes Thermocouples Ice bags Salt Sanitizing and sterilizing materials Adhesive bandages Subject incentive

References 1. Dolan MG, Thornton RM, Fish DR, Mendel FC. Effects of Cold Water Immersion on Edema Formation After Blunt Injury to the Hind Limbs of Rats. J Athl Train. 1997;32(3):233– 237. 2. Meeusen R, Lievens P. The use of cryotherapy in sports injuries. Sports Med. 1986;3(6):398–414. 3. Merrick MA, Jutte LS, Smith ME. Cold Modalities With Different Thermodynamic Properties Produce Different Surface and Intramuscular Temperatures. J Athl Train. 2003;38(1):28–33. 4. Sapega AA, Heppenstall RB, Sokolow DP, et al. The bioenergetics of preservation of limbs before replantation. The rationale for intermediate hypothermia. J Bone Joint Surg Am. 1988;70(10):1500–1513. 5. Dykstra JH, Hill HM, Miller MG, Cheatham CC, Michael TJ, Baker RJ. Comparisons of Cubed Ice, Crushed Ice, and Wetted Ice on Intramuscular and Surface Temperature Changes. J Athl Train. 2009;44(2):136–141. 6. Kennet J, Hardaker N, Hobbs S, Selfe J. Cooling Efficiency of 4 Common Cryotherapeutic Agents. J Athl Train. 2007;42(3):343–348. 7. Myrer JW, Draper DO, Durrant E. Contrast Therapy and Intramuscular Temperature in the Human Leg. J Athl Train. 1994;29(4):318–322.

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