Abstract:

Introduction:
Attendants of basic cardiopulmonary resuscitation (CPR) frequently do not apply ventilation due to its difficulties and the risk of infection by aerosols. Teaching ventilation during RCP training is a challenge since the trainee must keep open airway while he/she insufflate the lungs. A new device DARCP (Device for Support of CPR) has been recently designed with the aim to facilitate ventilation with facial mask, both with Ambu Bag or any ventilatory support, during CPR maintaining airway open.
The present study was a prospective observational study on the usability and opinion of its use at different levels of CPR health attendants.

Methods:
The study was carried out for 3 days in the first quarter of 2021 in a convenience sample. Participants gave their consent to participate in the study. Participants entered the scenario in pairs immediately after visualizing a 2.5 min homemade video showing how to assemble and use DARCP. The scenario was a simulated cardiac arrest on the floor, the different parts of the DARCP device were available besides the mannequin and they were asked to start immediately CPR with two reanimators using DARCP. Two independent observers evaluated participants performance filling out a rubric on the DARCP components assembly process, the global results and time spent for each assembly step. Participants individually responded to a questionnaire on a Likert scale ranging from 1 to 5, based on the System Usability Scale (SUS). CPR instructors filled out a questionnaire regarding the DARCP usefulness for CPR training.

Results:
Participants were 110 medical students of 1st year and 14 nursing students of 2n year (86% women, mean age 19.8+-2.1), 23 emergency doctors and nurses (mean professional experience 5.4+- 3.2 years, 70 % women) and 8 CPR certified instructors.
Managing to assemble DARCP was successfully done in less than 90s, started ventilation with Ambu in less than 2 min by 82% of student’s pairs and 96% of emergency professional’s pairs. All participants identified easily DARCP components, considered that it facilitated CPR and reanimators alternance, and improved their skills for mask ventilation; 91% considered that DARCP should be added to CPR courses. Lever for head hyperextension was missed or difficult to activate in 26% of students, 36 % of students’ pairs required to help each other in managing the hyperextension lever and the mask holder component. Emergency professional assembled DARCP more rapidly, in less than 1 min, agreed that CPR was facilitated for one reanimator and did not consider that it would hidden or delay CPR. They were more critical with design aspects but all of them were fully in favour to add DARCP intro their usual emergency equipment and did not considered. Concordance between evaluators was excellent.

Conclusion:
Testing DARCP use through simulation by different expertise levels allowed improvements in the informative material, reinforcing details on hyperextension mechanism and mask holder assembly and provided feedback to designers on which changes should be made to allow usability to all at CPR attendants of variable expertise. We consider that simulation centres where different levels of health professionals are trained are most efficient for assessing the usability of medical devices due to their facilities, organization and variable trainees levels.

Keywords:

Usability, cardiopulmonary resuscitation, healthcare devices, simulation, education.