Performance of Intravenous Insertion is Impaired Following Cold Water Immersion in Military Medical Providers

Abstract

Accidental cold water immersion or unprepared exposure to extreme cold temperatures can negatively impact warfighter performance and mission outcomes by hindering hands and feet use due to numbness. Skin or extremity temperature has been identified as a relevant variable that predicts impairment in manual dexterity and tactile sensitivity, yet no data have been presented showing performance of medically-specific tasks, such as intravenous (IV) insertion following a cold water immersion. PURPOSE: To determine the influence of cold water immersion and rewarming on IV insertion performance among military medical providers. METHODS: Thirty-eight military personnel (mean ± SD age: 25.8 ± 5.4 yrs, height: 179.5 ± 9.9 cm, weight: 83.2 ± 10.9 kg), trained in the technique of IV insertion, participated in a Cold Weather Medicine course. During the training exercise, students completed six stations: baseline in a classroom (5 min, 23° C), pre-immersion (pre) outdoors (5 min, -4.6° C), immersion in cold water (10 min, 0.2° C), post-immersion (post) (5 min, wet clothing, -4.6° C), transition (5 min, change into dry clothing), and rewarming (60 min, using various techniques). An IV insertion task was performed upon arrival at baseline, pre- and post-immersion, and after rewarming. The IV insertion task required students to insert an IV using a manikin arm. Students were assessed for time to insert IV and success of administering fluid. RESULTS: Assessment revealed a significant increase in IV insertion time (p<0.001) and a decrease in IV insertion success rate following cold water immersion. IV insertion times (seconds) for each station were: baseline 82 ± 17, pre 70 ± 12, post 168 ± 45, and rewarm 73 ± 14. IV insertion success rates were similar among baseline (76%), pre (71%), and rewarm (84%) stations; however, post-immersion, IV success trended downward (47%). CONCLUSION: Results were consistent with the expected loss of manual dexterity following cold water immersion. When given one hour of rewarming, performance returned to baseline. It is essential that military personnel are educated and trained on the effects of accidental cold exposure, the impact it may have on their performance as medical providers, and appropriate extremity rewarming techniques.