Sizing the lung in dogs: The inspiratory capacity defines the tidal volume Avaliação do tamanho do pulmão em cães: A capacidade inspiratória define o volume corrente

DONATI, PABLO ALEJANDRO; GOGNIAT, EMILIANO; MADORNO, MATÍAS; GUEVARA, JUAN MANUEL; GUILLEMI, ELIANA CAROLINA; DEL CARMEN LAVALLE, MARÍA; SCORZA, FRANCISCO PATRICIO; MAYER, GERMÁN FEDERICO; RODRIGUEZ, PABLO OSCAR

REVISTA BRASILEIRA DE TERAPIA INTENSIVA

Associacao de Medicina Intensiva Brasileira - AMIB

Lugar: San Pablo; Año: 2018 vol. 30 p. 144 - 152

0103-507X

Objective: To evaluate a novel physiological approach for setting the tidal volume in mechanical ventilation according to inspiratory capacity, and to determine if it results in an appropriate mechanical and gas exchange measurements in healthy and critically ill dogs. Methods: Twenty healthy animals were included in the study to assess the tidal volume expressed as a percentage of inspiratory capacity. For inspiratory capacity measurement, the mechanical ventilator was set as follows: pressure control mode with 35cmH2O of inspired pressure and zero end-expiratory pressure for 5 seconds. Subsequently, the animals were randomized into four groups and ventilated with a tidal volume corresponding to the different percentages of inspiratory capacity. Subsequently, ten critically ill dogs were studied. Results: Healthy dogs ventilated with a tidal volume of 17% of the inspiratory capacity showed normal respiratory mechanics and presented expected PaCO2 values more frequently than the other groups. The respiratory system and transpulmonary driving pressure were significantly higher among the critically ill dogs but below 15 cmH2O in all cases. Conclusions: The tidal volume based on the inspiratory capacity of each animal has proven to be a useful and simple tool when setting ventilator parameters. A similar approach should also be evaluated in other species, including human beings, if we consider the potential limitations of tidal volume titration based on the calculated ideal body weight.