Simulação in vitro da aspiração endotraqueal correlacionando pressão de vácuo, diâmetro do cateter e diferentes propriedades viscoelásticas para o muco respiratório

• Ano de defesa: 2015
• Autor(a) principal: Maria das Dores Cabral Ortis
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Muco; Aspiração endotraqueal; Pressão de sucção; Sucção; Bioengenharia; Engenharia mecânica
• Link de acesso: http://hdl.handle.net/1843/BUBD-A9CJ4T

Endotracheal suctioning is a necessary procedure to prevent airway obstruction for individuals in acute, severe or chronic disease, unable to keep clean your airway. The relationship between suction pressure, diameter of the catheter and its efficacy is not completely understood. Therefore an in vitro study was performed to relate suction pressure, diameter of the suction catheter, and amount of mass withdraw for three substances mucus simulant. An ARG2 rheometer (TA instruments) was used to permit the formulation and characterization of substances like a normal lung fluid, semifluid, and substances like secretions in pathological, semi-solid and intermediate stages, composed of locust bean gum and borax solutions. The negative pressures from the relationship between suction catheter and suction pressure were measured. The tests were performed for a 8mm endotracheal tube. 8, 10, 12, 15 and 16 Fr catheters were connected to vacuum at three different pressures: 100, 150 and 200 mmHg and the amount of the substance aspirated in each test situation was weighed. At 200 mmHg vacuum, a 14 Fr suction catheter can attain 2.38 mmHg with low potential for generating excessive intrapulmonary pressures in an 8mm endotracheal tube. The removal of 3.2g of substance, when considered three repetitions of the procedure, was satisfactory. A satisfactory amount of semifluid substance was aspirated for all combinations of vacuum applied pressure and catheter diameter. The intermediate substance was aspirated satisfactorily for 150 and 200 mmHg suction pressure using the 12 Fr catheter. A appropriate amount of semi-solid substance was aspirated for the 14 Fr catheter and 200 mmHg vacuum. The results suggest that increasing the vacuum while maintaining the same catheter diameter is safer and more effective than to increase the diameter to the next larger catheter.