Performance of emergency mechanical ventilators in response to the covid-19 pandemic: an intercomparison study.

Emergency mechanical ventilators developed during the pandemic were used to meet the high demand in intensive care units to care for COVID-19 patients. An example of such ventilators is Masi, developed in Peru and installed in more than 15 hospitals around the country. This study aimed to compare Masi's performance with other emergency mechanical ventilators manufactured during the covid-19 pandemic such as Neyün, Spiro Wave and a prototype developed by the Faculty of Engineering of the National University of Asuncion (FIUNA). Three configurations of a test lung were used, combining different values of resistance and compliance (C1, C2 and C3). Ventilators were set to volume-controlled ventilation with tidal volume = 400 mL, respiratory rate = 12 breaths/minute, and positive end-expiratory pressure (PEEP) = 8 cm H2O. These parameters were measured in a series of ten two-minute tests which then were evaluated through a two-way analysis of variance, considering the type of ventilator and test lung configuration as the two independent variables. For target values, MASI delivered VT that ranged from 319 to 432 ml (-20 to +8%), respiratory rate of 12 bpm, and PEEP from 8.4 to 9.5 cm H2O (+5 to +20%). In contrast, for instance, Neyün delivered VT that ranged from 199 to 543 ml (-50 to +35%) and PEEP from 7.05 to 9.21 cm H2O (--11 to +15%), with p<0.05. The analysis of variance showed that he differences between preset and delivered parameters were influenced by the type of ventilator and, significantly, by the test lung configuration.Clinical Relevance- This establishes the most advantageous conditions in which three emergency mechanical ventilators work and a quantitative perspective in this topic.

COVOX: Providing oxygen during the COVID-19 health emergency.

We introduce an autonomous oxygen concentrator that was designed in Peru to fight the oxygen shortage produced worldwide as a consequence of the COVID-19 pandemic. Oxygen concentrators represent a suitable and favorable option for administering this gas at the patient's bedside in developing countries, especially when cylinders and tubed systems are unavailable or when access to them is restricted by lack of accessories, inadequate power supply, or shortage of qualified personnel. Our system uses a pressure swing adsorption technique to provide oxygen to patients at a flow rate of up to 15 l/min ± 1,5 l/min and a concentration of 93 % ± 3 %, offering robustness, safety and functionality. The quality measurements obtained from the validation process demonstrate repeatability and accuracy. The complete design files are provided in the source file repository to facilitate oxygen concentrator production in low and middle income countries, where access to oxygen is still a major problem even after the pandemic. Oxygen is part of the World Health Organization Model List of Essential Medicines and is perhaps the only medicine that has no substitute. This device can provide a reliable supply of oxygen for critically ill patients and improve their chances of survival.

Extension of Non-invasive Ventilation Capabilities of MASI for the Care of Patients Affected by COVID-19.

The MASI mechanical ventilator was developed in a state of emergency to meet the demand for ventilators caused by COVID-19. Although it has obtained positive results in its use with patients in intensive care units, not having an optimal quality non-invasive ventilation (NIV) modality prevents it from being used in the early treatment of patients, which has been shown to prevent admission to the ICU and reduce mortality. Therefore, the following study focuses on evaluating MASI's ability to provide NIV using different accessories in order to compare their performance and determine which one would work best with MASI, and under which conditions. To do this, the high-flow nasal cannula, facial mask, and ventilation helmet accessories were tested under different pressure parameter settings. The data was collected using a gas flow analyzer. After that, a statistical analysis of the results was carried out, which showed that the face mask is the best accessory to use for NIV with MASI, and that it performs with optimal accuracy and precision when the peak inspiratory pressure is set at a value lower than 25 cmH20. Clinical Relevance- This study presents an optimization of the non-invasive ventilation (NIV) modality of the MASI me-chanical ventilator by evaluating its performance with different accessories.

Quality characteristics of the Masi Peruvian mechanical ventilator manufacturing process.

Three hundred and ten rapid-manufactured mechanical ventilators, named Masi, were produced and validated in Peru, according to applicable standards. From these, a sample of 30 was taken and two ventilation parameters, tidal volume and peak inspiratory pressure, were statically analyzed using control charts and histograms. Results show that several points were outside estimated limits for Shewhart means and ranges charts, which could possibly be due to the quantity of equipment used for data recollection and the fact that the Masi team had over 20 engineers. Nevertheless, Masi ventilators met the tolerance required by their user´s manual and MHRA standard and Peruvian DIGEMID for every parameter.Clinical Relevance-This article shows the performance in the validation stage of the peruvian mechanical ventilator MASI built as an emergency response for the COVID-19 crisis.

Performance of the Masi Peruvian ventilator at high altitude.

In response to Covid-19 crisis, 310 Masi ventilators were produced and validated in Lima, Peru, according to applicable standards. Four of them, were transported to Puno, in order to strengthen ICU Services there, but this set a major challenge to Masi team as effects of altitude on ventilators were unknown. Once there, ventilators were acclimated and calibrated. Volume tidal, I:E ratio, respiratory frequency and PEEP were tested, all of them presenting errors under 15%, except for tidal volume, for which a 25% negative correction was applied. After the installation of a new version of Masi software, parameters were tested again, all of them presenting results with errors below 15%, which allowed the Masi team to take them to ICU services for use.Clinical Relevance- Masi Peruvian Ventilators are able to perform according to their specifications at extremely high altitude, after the adequate calibration. These devices are an alternative to treat COVID-19 patients in the middle of the crisis.