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Acute muscle fatigue and CPR quality assisted by visual feedback devices: a randomized-crossover simulation trial

Abelairas-Gomez, C.·Rey, E.·Gonzalez-Salvado, V.·Mecias-Calvo, M.·Rodriguez-Ruiz, E.·Rodriguez-Nunez, A.
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Abstract

ObjectiveTo analyse the acute muscular fatigue (AMF) in triceps brachii and rectus abdominis during compression-only and standard cardiopulmonary resuscitation (CPR) performed by and certified basic life support providers.\n\nMethodsTwenty-six subjects were initially recruited and randomly allocated to two study groups according to the muscles analysed; eighteen finally met the inclusion criteria (nine in each group). Both groups carried out two CPR tests (compression-only and standard CPR) of 10 min divided into five 2-min intermittent periods. The ventilation method was freely chosen by each participant (mouth-to-mouth, pocket-mask or bag-valve-mask). CPR feedback was provided all the time. AMF was measured by tensiomyography at baseline and after each 2-min period of the CPR test, in triceps brachii or rectus abdominis according to the study group.\n\nResultsRectus abdominis contraction time increased significantly during the fifth CPR period (p = 0.020). Triceps brachiis radial muscle belly displacement (p = 0.047) and contraction velocity (p = 0.018) were lower during compression-only CPR than during standard CPR. Participants who had trained previously with feedback devices achieved better CPR quality results in both protocols. Half of participants chose bag-valve-mask to perform ventilations but attained lower significant ventilation quality than the other subjects.\n\nConclusionsCompression-only CPR induces higher AMF than standard CPR. Significantly higher fatigue levels were found during the fifth CPR test period, regardless of the method. Adequate rescuers strength seems to be a requisite to take advantage of CPR quality feedback devices. Training should put more emphasis on the quality of ventilation during CPR.

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Abelairas-Gomez, C., Rey, E., Gonzalez-Salvado, V., Mecias-Calvo, M., Rodriguez-Ruiz, E., Rodriguez-Nunez, A.. 2018-08-24. Acute muscle fatigue and CPR quality assisted by visual feedback devices: a randomized-crossover simulation trial. https://doi.org/10.1101/399949

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