ABSTRACT
Purpose In the COVID-19 outbreak periods, people's life has been deranged, leading to disrupt the world. Firstly, the number of deaths is growing and has the potential to surpass the highest level at any time. Secondly, the pandemic broke many countries' fortified lines of epidemic prevention and gave people a more honest view of its seriousness. Finally, the pandemic has an impact on life, and the economy led to a shortage in medical, including a lack of clinicians, facilities and medical equipment. One of those, a simple ventilator is a necessary piece of medical equipment since it might be useful for a COVID-19 patient's treatment. In some cases, the COVID-19 patients require to be treated by modern ventilators to reduce lung damage. Therefore, the addition of simple ventilators is a necessity to relieve high work pressure on medical bureaucracies. Some low-income countries aim to build a simple ventilator for primary care and palliative care using locally accessible and low-cost components. One of the simple principles for producing airflow is to squeeze an artificial manual breathing unit (AMBU) iterative with grippers, which imitates the motion of human fingers. Unfortunately, the squeezing angle of grippers is not proportional to the exhaust air volume from the AMBU bag. This paper aims to model the AMBU bag by a mathematical equation that enables to implement on a simple controller to operate a bag-valve-mask (BVM) ventilator with high accuracy performance. Design/methodology/approach This paper provides a curvature function to estimate the air volume exhausting from the AMBU bag. Since the determination of the curvature function is sophisticated, the coefficients of the curvature function are approximated by a quadratic function through the experimental identification method. To obtain the high accuracy performance, a linear regression model and a least square method are employed to investigate the characteristic of the BVM ventilator's grippers angle with respect to the airflow volume produced by the AMBU bag. Findings This paper investigates the correlation between the exhausting airflow of the AMBU bag and the grippers angle of the BVM ventilator. Originality/value The experimental results validated that the regression model of the characteristic of the exhausting airflow of the AMBU bag with respect to the grippers' angle has been fitted with a coefficient over 98% within the range of 350-750 ml.
ABSTRACT
Ventilators are drawn to many researchers during the Covid-19 pandemic because it's essential equipment that's accustomed to treat severe Covid-19 patients. In low-income countries, there's a shortage of pricy respiratory devices resulting in exceeding the provision of taking care of Covid-19's patients in ICU. This paper attempts to design and implement an appropriate respiratory device referred to as a bag valve mask (BVM) ventilator for those who are Covid-19 patients in medical care, those patients have a requirement of safe transport and also palliative care. The BVM ventilator comprises a man-made manual breath unit (AMBU) bag and paddles for squeezing the AMBU bag which is popular in medical aid settings. The BVM ventilator is required to travel airflow through the system to the patient's lung with the specified volume for every breath cycle within a threshold air pressure. Since the AMBU bag is straightforward to be deformed over time, it's difficult to get mathematical modelling for constructing a reliable controller. Therefore, a model-free control (MFC) control approach is utilized successfully to style a controller for our BVM ventilator model with a PEEP valve and a HEPA filter. Some experimental scenarios are administered to gauge the effectiveness of the proposed controller for the BVM ventilator to control the airflow and control air pressure mode.
ABSTRACT
Objective: To assess the acceptance of coronavirus disease (COVID-19) vaccine among healthcare workers at two general hospitals in Vietnam when it is available. Methods: A cross-sectional study was conducted using a convenience sampling from January to February 2021 among 410 healthcare workers at two general hospitals in Vietnam via a self-administered questionnaire. A multivariable regression analysis was performed to determine predictors of vaccine acceptance including the demographic factors, COVID-19 knowledge, and vaccine beliefs based on the domains of Health Belief Model. Results: Among 410 healthcare workers, 76.10% showed vaccination willingness. Predictors of acceptance were determined that the group reporting as 'vaccine acceptance' was more likely to be positive towards the perceived susceptibility and severity of COVID-19 (OR 2.45;95% CI 1.48-4.06, P<0.05), perceived benefits of vaccination, and cues to action (OR 4.36;95% CI 2.35-8.09, and OR 5.49;95% CI 2.84-10.61, respectively, all P<0.001), but less likely to have the perceived barriers to vaccination (OR 0.19;95% CI 0.09-0.38;P<0.001) compared with the no acceptance group. Besides, people who had a good knowledge regarding the severity of illness were 3.37 times more likely to have identified as vaccine acceptance (OR 3.37;95% CI 1.04-10.86, P<0.05). The demographic factors were also associated with willingness to receive the vaccine, with participants who were staff and received COVID-19 information from relatives were less likely to accept the vaccine over those who were doctors and not receiving information from relatives (OR 0.36;95% CI 0.13-0.96, and OR 0.37;95% CI 0.17-0.78, respectively, all P<0.05). Conclusions: A rate of willingness to get vaccinated against COVID-19 was relatively high with discrepancies between occupation, receiving information from relatives, knowledge toward the severity of illness, and the elements of Health Belief Model. The findings will provide information for the management authorities to develop relevant interventions to promote COVID-19 vaccination uptake. © 2021 Asian Pacific Journal of Tropical Medicine Produced by Wolters KluwerMedknow. All rights reserved.