Laminar flowmeter for mechanical ventilator: Manufacturing challenge of Covid-19 pandemic

Alsalaet, Jaafar; Munahi, Basil Sh.; Al-Sabur, Raheem; Al-Saad, Mohammed; Ali, Abdulbaki K.; B, Abdulbaseer Shari; Fadhil, Hayder Ali; Laftah, Rafil Mahmood; Ismael, Muneer A.

doi:10.1016/j.flowmeasinst.2021.102058

Cited by 9 publications

(4 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Contrary to the complex and expensive fabrication process required by pneumotachographs based on narrow capillaries (Fleisch-type) or mesh screen (Lilly-type), or to alternatives requiring a 3D printer ( 23 ), the proposed resistor can be constructed at virtually no cost by simply drilling any material including metals and non-toxic sterilizable polymers (rather than the PVC used in this study as proof of concept). It must be acknowledged, however, that such simplifications in the resistor construction imply the assumption of non-linearity.…”

Section: Discussionmentioning

confidence: 99%

Simple low-cost construction and calibration of accurate pneumotachographs for monitoring mechanical ventilation in low-resource settings

et al. 2022

View full text Add to dashboard Cite

Assessing tidal volume during mechanical ventilation is critical to improving gas exchange while avoiding ventilator-induced lung injury. Conventional flow and volume measurements are usually carried out by built-in pneumotachographs in the ventilator or by stand-alone flowmeters. Such flow/volume measurement devices are expensive and thus usually unaffordable in low-resource settings. Here, we aimed to design and test low-cost and technically-simple calibration and assembly pneumotachographs. The proposed pneumotachographs are made by manual perforation of a plate with a domestic drill. Their pressure-volume relationship is characterized by a quadratic equation with parameters that can be tailored by the number and diameter of the perforations. We show that the calibration parameters of the pneumotachographs can be measured through two maneuvers with a conventional resuscitation bag and by assessing the maneuver volumes with a cheap and straightforward water displacement setting. We assessed the performance of the simplified low-cost pneumotachographs to measure flow/volume during mechanical ventilation as carried out under typical conditions in low-resource settings, i.e., lacking gold standard expensive devices. Under realistic mechanical ventilation settings (pressure- and volume-control; 200–600 mL), inspiratory tidal volume was accurately measured (errors of 2.1% on average and <4% in the worst case). In conclusion, a simple, low-cost procedure facilitates the construction of affordable and accurate pneumotachographs for monitoring mechanical ventilation in low- and middle-income countries.

show abstract

Section: Discussionmentioning

confidence: 99%

Simple low-cost construction and calibration of accurate pneumotachographs for monitoring mechanical ventilation in low-resource settings

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Given that the study was carried out during the coronavirus (COVID-19) pandemic and considering the pivotal role of 3D printers in manufacturing essential medical models [59], a convenience sampling technique was used, which is a non-probabilistic and nonrandom sampling technique. A total of 31 subjects were invited to participate according to the following inclusion criteria: gender not specified (45% women and 55% men); over 18 years old (average of 22 years); and students of bachelor's and graduate degrees who also have different levels of expertise (novice and expert user) when considering the frequency of use of a 3D printer.…”

Section: Participantsmentioning

confidence: 99%

A Hierarchical Axiomatic Evaluation of Additive Manufacturing Equipment and the 3D Printing Process Based on Sustainability and Human Factors

Mendoza-Muñoz,

Montoya-Reyes,

Maldonado-Macías

et al. 2024

Processes

View full text Add to dashboard Cite

As interest in additive manufacturing (AM) continues to increase, it has become more important to have a robust method to help potential users select the AM process that best suits their technological needs while providing the greatest potential benefits in terms of sustainability and its effect on people. This paper presents the development of a framework for selecting the best AM process for a given application by considering both sustainability and human factors through the combination of axiomatic design and the analytic hierarchy process. Thirty-one participants with varying levels of expertise (novice and advanced users) were involved in the study, considering the frequency of 3D printer usage (novice users: never, rarely; expert users: sometimes, almost always, always) for prototyping parts. They employed fused deposition modeling (FDM) and stereolithography (SLA) (both 3D desktop printers) and collected data on five evaluation criteria. The participation of experts helped establish a novel methodology, with material cost deemed most important (49.8%), followed by cycle time (28%), energy consumption (11.7%), error rate (6.6%), and equipment noise (3.9%). The results showed that FDM was the optimal equipment option for advanced users. By examining the information content of the other options, it was found that FDM demanded less information than SLA, regardless of the user’s level of expertise. The proposed method is appropriate to assess the sustainability aspect of FDM and SLA; however, it can be further improved by adding indicators such as environmental impact, recyclability, and ergonomic and occupational health factors.

show abstract

“…Todos estes tem um mecanismo de funcionamento similar. Os transdutores possuem um diafragma em que a pressão diferencial é aplicada e medida através do deslocamento ou da tensão gerada em um dos lados do diafragma (TOGAWA; TAMURA; OBERG, 2011).A medição da pressão diferencial na avaliação da mecânica respiratória é ferramenta essencial ao uso de fluxômetros do tipo resistência linear (tanto Lilly e Fleisch) e do tipo orifício (tanto variável quanto fixo) para medição do fluxo(ALSALAET et. al, 2021).2.8.2.…”

unclassified

“…Nesta dissertação foi utilizado o pneumotacógrafo de resistência linear do tipo Lilly, explicado adiante na seção 3.2.8.2.1. Pneumotacógrafo de resistência linearTambém conhecidos como fluxômetros laminares(ALSALAET et. al, 2021), os pneumotacógrafos de resistência linear possuem uma estrutura que consiste na presença de um elemento resistivo posicionado em um conduto tubular e por ali se passa um fluxo livre de gases.…”

unclassified

Ventilação mandatória contínua modo volume controlado: análise de desempenho essencial de ventiladores pulmonares quando submetidos a quatro cenários da norma ABNT NBR ISO 80601-2-12.

Lopes

View full text Add to dashboard Cite

Pulmonary ventilators have received great attention in recent years due to the impact of health scenario the world faced. These devices and their ventilatory modes are responsible for providing safer and more effective ventilation in the most diverse respiratory conditions that can affect a patient. Among the ventilation modes available in critical care ventilators there is the Continuous Mandatory Ventilation mode with volume control (CMV-VC), used in patients whose respiratory effort is null, such as in situations of neuromuscular blockade. In this mode, the ventilator aims to ensure the delivery of a volume to the patient's lung, changing its flow and pressure parameters and monitoring this delivery. Ventilatory modes have been evaluated by researchers over the years and their operational oscillations have been documented while the equipment is bench-tested. However, some works found in the literature adopt scenarios for assessing ventilatory performance that are different from each other, regarding the metrics, methodology and equipment configurations adopted. In addition, many of these studies analyze models of high-cost ventilators, which, generally, is not the reality found in a large part of the Brazilian territory. Thus, this dissertation has the main purpose of comparing the ventilatory parameters and their waveform patterns of five different lung ventilators found in the Brazilian scenario when they are operating in CMV-VC mode. It is also intended to detail the entire methodology in which the measurements were carried out and to evaluate the essential performance of this equipment considering the technical standard ABNT NBR ISO 80601-2-12: 2014 as a premise. A data acquisition system with a sampling frequency of 100 Hz obtained flow and pressure data from each device. The setup of the experiment present in the ABNT NBR ISO 80601-2-12: 2014 standard was used so that the tests were carried out in four scenarios for evaluating the CMV-VC mode, in which lung compliance and resistance varied in different combinations. For all scenarios, the volume to be delivered should be 500 mL. Positive end-expiratory pressure (PEEP) and inspiratory time (Tins) parameters were also evaluated. Despite being submitted to the same four scenarios, ventilators showed differences in PEEP and volume parameters, while Tins behaved similarly in all situations. Positive endexpiratory pressure (PEEP) and inspiratory time (Tins) parameters were also satisfactory. Despite being tolerant of the same four scenarios, ventilators differed in PEEP and volume parameters, especially in scenarios 3 and 4 where compliance and lung resistance were higher. Tidal volumes ranged from 381.49 to 591.15 mL, PEEP from 3.58 to 3.75 cmH2O in scenarios 1 and 3 and from 8.37 to 9.61 cmH2O in scenarios 2 and 4, while Tins ranged from 0.86 to 1.05 s in the measurement system proposed by the standard. Additionally, a mechanical ventilation evaluation system, commercially available in the national market, was used and the results were compared.

show abstract

Laminar flowmeter for mechanical ventilator: Manufacturing challenge of Covid-19 pandemic

Cited by 9 publications

References 17 publications

Simple low-cost construction and calibration of accurate pneumotachographs for monitoring mechanical ventilation in low-resource settings

Simple low-cost construction and calibration of accurate pneumotachographs for monitoring mechanical ventilation in low-resource settings

A Hierarchical Axiomatic Evaluation of Additive Manufacturing Equipment and the 3D Printing Process Based on Sustainability and Human Factors

Ventilação mandatória contínua modo volume controlado: análise de desempenho essencial de ventiladores pulmonares quando submetidos a quatro cenários da norma ABNT NBR ISO 80601-2-12.

Contact Info

Product

Resources

About