A New Full-Face Mask for Multifunctional Non-Invasive Ventilation

Abstract

Background: Noninvasive ventilation (NIV) provides positive pressure through different interfaces. A multifunctional full-face mask prototype was developed to provide NIV from three sources: ICU ventilators, portable ventilators, and high-flow medical gas pipeline systems. This study aimed to evaluate the usability of this prototype mask. Methods: This was a quantitative experimental study, conducted in two phases: the development of a full-face mask prototype NIV interface, and the evaluation of its usability by health professionals (evaluators) using a heuristic approach. The Wolf Mask prototype is a multifunctional full-face mask that makes it possible to deliver positive pressure from three different sources: microprocessor-controlled ICU ventilators, portable ventilators with single-limb circuits, and high-flow medical gas. The evaluation was conducted in three stages: presentation of the prototype to the evaluators; skills testing via simulation in a clinical environment; and a review of skills. Results: The prototype was developed by a multidisciplinary team and patented in Brazil. The evaluators were 10 health professionals specializing in NIV. Seven skills related to handling the prototype were evaluated. Three of the ten evaluators called for (non-urgent) changes to improve recognition of the components of the prototype. Only one evaluator called for (non-urgent) changes to improve recognition of the pieces, assembly, and checking the mask. Conclusions: The newly developed multifunctional full-face mask prototype demonstrated excellent usability for providing noninvasive ventilation from multiple sources. Minor modifications may further improve the design.

Keywords: heuristics; noninvasive ventilation; user-centered design.

Figure 1

Flow diagram of the evaluation process and outcomes.

Figure 2

Improvements made to the Wolf Mask prototype. (A) Valves with identification of the inspiratory branch connection, expiratory branch connection, inlet for the use of supplemental oxygen, and exhalation valve. (B) The interface of the prototype with valves after the improvements. (C) Checking the pressure within the mask using a cuff manometer, which showed the pressure to be 10 cmH₂O when the flow (of medical gas) was above 40 L/min.

Figure 3

Healthy volunteer using the Wolf Mask prototype (A) with a microprocessor-controlled ventilator with a dual-limb circuit; (B) with the exhalation valve incorporated into the interface itself, connected to a single-limb circuit bilevel device; and (C) with a high-flow medical gas pipeline systems. Below each photo, see physiological parameter monitors showing CO₂ exhalation via capnography in yellow.

Figure 4

(A) Healthy volunteer using the Wolf Mask prototype with a single-limb circuit bilevel device and exhalation valve in the interface itself coupled to a flow analyzer. (B) Flow analyzer showing the expiratory flow rate in the exhalation valve of the prototype.

Figure 5

The final version of the Wolf Mask prototype. (A) Illustration showing the distribution of air inflow and outflow (inspiration and expiration). (B) Illustration showing the five elements of the prototype.