CPAP Hardware/Simulation and Control Design for Respiratory Disorders: A Review

Continuous Positive Airway Pressure (CPAP) ventilation remains a mainstay treatment for different respiratory disorders. Good pressure stability and pressure reduction during exhalation are of major importance condition to ensure the clinical efficacy and comfort of CPAP therapy. Obstructive Sleep Apnea (OSA) and today coronavirus (COVID-19) are the main two diseases mitigated by the CPAP. This paper introduced a systematic review of the CPAP design in terms of the hardware design, Simulation-based CPAP system, control algorithm, and the measured performance. The accuracy is used as measurement of performance and calculated from the pressure value. The accuracy was compared to the predefined U.S. Food and Drug Administration (FDA)-based threshold value in which it considers this value as a reference. The results related to the modern CPAP devices introduced in this study to explain the accuracy of experimental CPAP. These were compared with a commercial CPAP devices. Also, it was revealed how the results coincide with the error ratio defined by the FDA as an evaluation measurement. The FDA error ratio determines the performance of the optimized CPAP device. This work is the first review that presented the knowledge about engineering design of the CPAP system, so it will be the first in the literature.

The Suitable Machine: Exploring style through storytelling to inform design

<p>The Suitable machine demonstrates how aesthetic change can be made to a Continuous Positive Air Pressure (CPAP) device, allowing it to suit the visual style of a specified bedroom environment that has been described. Digital data (3D scans) of the CPAP device provided specific measurements allowing a wide variety of aesthetically styled outputs that were tailored to fit. Each suitable to the people, home and machine they are designed for. CPAP devices that are used to treat patients with Obstructive Sleep Apnea (OSA) are considered strongly driven by a medical aesthetic. The Suitable Machine explores how CPAP devices, hoses and masks can be housed within these bedroom settings, producing designs to personalise the domestic environment and reduce stigma through the improvement of aesthetic qualities. The research uses Research Through Design (RtD) as a methodology. Background Research, Design Audits and Narratives are used to define the scope and criteria, providing parameters for the research and design outputs. Background research shows both knowledge gaps and bias to a growing dilemma; suitability. Development of the designed outputs makes use of Sketching, 3D Scanning, CAD Modelling, digital Rendering and 3D Printing as methods; producing an experimental indication of what could be possible for the personalisation of medical devices through aesthetic change in domestic environments.</p>

The Suitable Machine: Exploring style through storytelling to inform design

<p>The Suitable machine demonstrates how aesthetic change can be made to a Continuous Positive Air Pressure (CPAP) device, allowing it to suit the visual style of a specified bedroom environment that has been described. Digital data (3D scans) of the CPAP device provided specific measurements allowing a wide variety of aesthetically styled outputs that were tailored to fit. Each suitable to the people, home and machine they are designed for. CPAP devices that are used to treat patients with Obstructive Sleep Apnea (OSA) are considered strongly driven by a medical aesthetic. The Suitable Machine explores how CPAP devices, hoses and masks can be housed within these bedroom settings, producing designs to personalise the domestic environment and reduce stigma through the improvement of aesthetic qualities. The research uses Research Through Design (RtD) as a methodology. Background Research, Design Audits and Narratives are used to define the scope and criteria, providing parameters for the research and design outputs. Background research shows both knowledge gaps and bias to a growing dilemma; suitability. Development of the designed outputs makes use of Sketching, 3D Scanning, CAD Modelling, digital Rendering and 3D Printing as methods; producing an experimental indication of what could be possible for the personalisation of medical devices through aesthetic change in domestic environments.</p>

Determinants of adherence to continuous positive airway pressure therapy in adults with obstructive sleep apnea

Objectives Adherence to continuous positive airway pressure (CPAP) devices in patients with obstructive sleep apnea (OSA) determines the effectiveness of the treat- ment. Likewise, the assessment of the control of the disease must consider the infor- mation referred by the patient, among other value-based health measures related to the satisfaction of the intervention. The objectives of this study were a) Determine the factors related to adherence to CPAP devices in subjects with OSA affiliated to an insurance company of the healthcare system in Colombia. b) Assess symptom control associated to the disease from the individual ́s perspective and his/her satisfaction with the treatment received. Materials and Methods 1,501 subjects with OSA were surveyed by telephone to explore: sociodemographic factors, habits and lifestyles, use of CPAP and its adverse events, control of the disease, comorbidities, access to care and therapy satisfaction. Using multilevel logistic regression techniques, the influence of the various factors on adherence to CPAP was analyzed, using Stata 13 software. Results Adherence to CPAP therapy was of 58% and the control of symptoms was of 41.7%. The factors that determined the use of CPAP were knowledge on how the device operates, and the disturbances during sleep due to the mask or nasal pad. The- rapy satisfaction was predominantly very good or good. Conclusion Even with moderate adherence values and a good experience with CPAP therapy, symptomatic control of the disease is poor. Many of the factors that affect the use of CPAP are modifiable with a proper approach by the devices ́ service provider.

Respiratory failure: technical means for diagnosis and respiratory support

The necessity of early diagnosis of respiratory diseases, especially in the context of the COVID-19 pandemic, by means of pulse oximetric screening and monitoring has been substantiated. The expediency of using portable pulse oximeters by therapists and general practitioners has been shown. The main respiratory diseases accompanied by respiratory failure, which can be detected in time by pulse oximetry, are the chronic obstructive pulmonary disease and the obstructive sleep apnea-hypopnea syndrome. Early detection of these diseases is an important task because of the mild symptoms of these diseases in the early stages, and as a result, the prevalence of late diagnosis. Special attention is given to the pulse oximetry for COVID-19 detection, as this infection is also accompanied by respiratory failure. The use of oxygen concentrators and auto CPAP devices for the treatment of respiratory failure as well as rehabilitation has been argued. The effectiveness of the appointment of long-term oxygen therapy using oxygen concentrators for patients with chronic obstructive pulmonary disease, CPAP therapy using automatic CPAP devices for patients with obstructive sleep apnea-hypopnea syndrome with mandatory pulse oximetry monitoring has been confirmed. The analysis of 120 cases of treatment of moderate and severe COVID-19 cases complicated by the pneumonia has been carried out. The efficiency of the use of oxygen concentrators for supplying oxygen to patients at a flow rate not more than 5 l/min has been proven. It has been found that no more than 10 % of patients needed an oxygen flow rate more than 5 l/min. At the same time, the possibility of using CPAP devices for non-invasive ventilation of lungs using full-face masks has been shown. The expediency of using oxygen concentrators and CPAP devices for the rehabilitation of patients after COVID-19 has been noted.

A Non-Framework Multilevel Surgery May Reduce Mean Heart Rate in Patients with Very Severe Obstructive Apnea Having Confined Retroglossal Space and Framework

An elevated mean heart rate in untreated patients of obstructive sleep apnea (OSA) may lead to a higher risk of mortality and the development of various cardiovascular diseases. The elevation may positively relate to the severity of OSA and present in both wakefulness and sleep. A reduction in heart rate has been presented in reports of treating OSA patients with continuous positive airway pressure (CPAP). However, patients with very severe OSA may refuse use of CPAP devices and advocated surgeries, such as direct skeletal surgery or tracheostomy. It is unclear whether the non-framework multilevel surgery we reported previously can overcome the unfavorable anatomy and reduce mean heart rate, which serves as a risk factor of mortality. Here, we show that multilevel surgery reduced the mean heart rate from 68.6 to 62.7 with a mean reduction of 5.9 beats/min. The results suggest that the surgery may reduce the risk of consequences and mortality associated with an elevated mean heart rate, such as various cardiovascular diseases. We disclose these findings, along with the variations and possible risks to our future patients with very severe OSA who refuse or cannot use a CPAP device or reject direct skeletal surgery.