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AbstractIntroduction:The Stop the Bleed campaign provided civilians with tourniquet application training and increased the demand for tourniquets among the general population, which led to the development of new commercially available devices. However, most widely available tourniquets have not undergone testing by regulatory bodies and their efficacy remains unknown.Study Objective:This study aimed to compare the efficacy and performance of Combat Application Tourniquets (CAT) versus uncertified tourniquets.Methods:This study compared 25 CAT with 50 commercially available “look-alike” tourniquets (LA-TQ) resembling the CAT. The CAT and the LA-TQ were compared for cost, size, and tested during one-hour and six-hour applications on a manikin’s leg. The outcomes were force applied, force variation during the application, and tourniquet rupture rate.Results:The LA-TQ were cheaper (US$6.07 versus US$27.19), shorter, and had higher inter-device variability than the CAT (90.1 [SE = 0.5] cm versus 94.5 [SE = 0.1] cm; P <.001). The CAT applied a significantly greater force during the initial application when compared to the LA-TQ (65 [SE = 3] N versus 14 [SE = 1] N; P <.001). While the initial application force was maintained for up to six hours in both groups, the CAT group applied an increased force during one-hour applications (group effect: F [1,73] = 105.65; P <.001) and during six-hour applications (group effect: F [1,12] = 9.79; P = .009). The rupture rate differed between the CAT and the LA-TQ (0% versus 4%).Conclusion:The LA-TQ applied a significantly lower force and had a higher rupture rate compared to the CAT, potentially affecting tourniquet performance in the context of public bleeding control. These findings warrant increased layperson education within the framework of the Stop the Bleed campaign and further investigations on the effectiveness of uncertified devices in real-world applications.

Do brain circuits become fatigued due to intensive neural activity or plasticity? Is sleep necessary for recovery? Well-rested subjects trained extensively in a visuo-motor rotation learning task (ROT) or a visuo-motor task without rotation learning (MOT), followed by sleep or quiet wake. High-density electroencephalography showed that ROTtraining led to broad increases in EEG power over a frontal cluster of electrodes, with peaks in the theta (mean ± SE: 24% ± 6%, p= 0.0013) and beta ranges (10% ± 3%, p= 0.01). These traces persisted in the spontaneous EEG (sEEG) between sessions (theta: 42% ± 8%, p= 0.0001; beta: 35% ± 7%, p= 0.002) and were accompanied by increased errors in a motor test with kinematic characteristics and neural substrates similar to ROT(81.8% ± 0.8% vs. 68.2% ± 2.3%; two-tailed paired t-test: p= 0.00001; Cohen’s d= 1.58), as well as by score increases of subjective task-specific fatigue (4.00 ± 0.39 vs. 5.36 ± 0.39; p= 0.0007; Cohen’s d= 0.60). Intensive practice with MOTdid not affect theta sEEG or the motor test. A nap, but not quiet wake, induced a local sEEG decrease of theta power by 33% (SE: 8%, p= 0.02), renormalized test performance (70.9% ± 2.9% vs 79.1% ± 2.7%, p= 0.018, Cohen’s d= 0.85), and improved learning ability in ROT(adaptation rate: 71.2 ± 1.2 vs. 73.4 ± 0.9, p= 0.024; Cohen’s d= 0.60). Thus, sleep is necessary to restore plasticity-induced fatigue and performance.