Research on System Design to Support Medical Staff in Case of Ventilator Alarms

Abstract

Objective In this study, we will measure the nurse’s behavior when the ventilator’s alarm happened from a cognitive perspective and clarify the background. Based on the results, we will create a cognitive model and identify the important points for creating a support system. Introduction The frequency of ventilator use is increasing due to COVID-19. Therefore, there is an increasing need for staff who can properly manipulate ventilators. In particular, there is a need for training and support systems to enable operators to manipulate the equipment accurately when the Ventilator’s alarm happen. Methods The operator manipulate to a simulated ventilator alarms. The verbal protocols is measured to understand the operator’s thoughts during the manipulation. After the experiment, reflect on the measured recordings with the participants and review the reasons for their utterance and behavior. Results As a result of behavioral analysis, it was divided into a group that can clear the alarm (Skilled Group, IG) and a group that takes time to clear the alarm or cannot clear it (Inexperienced Group, IG). We found that the IG was not able to make decisions to manipulate differently depending on the patient’s ventilation status. We also identified the cognitive reasons behind the behaviors based on the verbal protocols data and developed a cognitive model of the operator. Application The results of this study could be applied to the operation of ECMO (Extracorporeal Membrane Oxygenator) and other medical equipment, for example, as well as to the manipulation to alarms.

Appendix

List of Technical terms (italic font style).

• 1. Ventilator: An equipment that helps ventilate a patient with weak breathing. It is also called mechanical assist ventilation. When ventilation is impaired, it cannot be improved by oxygen administration alone. It is necessary to use a ventilator to apply pressure to the lungs to encourage and support respiratory movement.

• 2. Gas exchange in the lungs: Oxygen taken into the lungs is transferred into the blood by diffusion through the alveolar membrane, and at the same time carbon dioxide in the blood is expelled into the alveoli. This is called gas exchange.

• 3. Expired minute volume: “Expired minute volume” is the expiratory ventilation volume per minute.

  It is multiplied by the volume of each breath and the number of breaths. It can be expressed as: Expired minute volume [L/min] = volume of one breath [mL/breath] × number of breaths [breaths/min].

  For example, for a patient weighing 60[kg], if the standard is 10 [mL/kg] per breath, the volume of each breath is 600 [mL]. If the standard respiratory frequency is 12 [breaths/min], the expiratory minute ventilation volume is 7.2 [L/min].

• 4. Tubing connection incorrectly: Incorrect connection of the tube connecting the ventilator to the patient.

  For example, wrong connection of the tubing, disconnection of the tubing, cracks in the tubing, bending of the tubing, or insufficient air in the intubation tube cuff. When these cause air leaks, the amount of air delivered to the patient (ventilation volume) is reduced.

• 5. SARS: Severe Acute Respiratory Syndrome, 2002

• 6. MERS: Middle East Respiratory Syndrome, 2012

• 7. ECMO: Extracorporeal Membrane Oxygenation, An extracorporeal circulatory device used to support the respiration and circulation of patients in critical condition due to pneumonia or acute myocardial infarction.