Liquid ventilation

Abstract

Human have lungs to breathe air and they have no gills to breath liquids like fish. When the surface tension at the air-liquid interface of the lung increases as in acute lung injury, scientists started to think about filling the lung with fluid instead of air to reduce the surface tension and facilitate ventilation. Liquid ventilation (LV) is a technique of mechanical ventilation in which the lungs are insufflated with an oxygenated perfluorochemical liquid rather than an oxygen-containing gas mixture. The use of perfluorochemicals, rather than nitrogen as the inert carrier of oxygen and carbon dioxide offers a number of advantages for the treatment of acute lung injury. In addition, there are non-respiratory applications with expanding potential including pulmonary drug delivery and radiographic imaging. It is well-known that respiratory diseases are one of the most common causes of morbidity and mortality in intensive care unit. During the past few years several new modalities of treatment have been introduced. One of them and probably the most fascinating, is of LV. Partial LV, on which much of the existing research has concentrated, requires partial filling of lungs with perfluorocarbons (PFC's) and ventilation with gas tidal volumes using conventional mechanical ventilators. Various physico-chemical properties of PFC's make them the ideal media. It results in a dramatic improvement in lung compliance and oxygenation and decline in mean airway pressure and oxygen requirements. No long-term side-effect reported.

Microfluidic chambers using fluid walls for cell biology

“…They are also the carrier fluid of choice in droplet-based microfluidics. In addition, FC40 carries the vital gases (O 2 and CO 2 ) so effectively that it has been used as a blood substitute ( 17 ), and FC40’s close relatives have been used for liquid ventilation of human preterm neonates ( 18 , 19 ). FC40 also prevents the underlying aqueous layer from evaporating (the solubility of water in FC40 is <7 ppm by weight at room temperature) while isolating each chamber from others in a dish (and from the surroundings), thereby preventing contamination and communication between adjacent chambers.…”

“…The platform has another significant advantage: It is biocompatible if used with the culture media and dishes (including coated ones; SI Appendix , Fig. S4 A and B ) familiar to biologists, along with what is arguably the most bio-inert immiscible liquid available—FC40 ( 17 – 19 ). Cells (from bacteria to humans) grow normally in grids ( Figs.…”

In vivo clearance of nanoparticles by transcytosis across alveolar epithelial cells

“…PFC also improved the microscopy (see “discussion”). During the microscopy, the animals were subjected to partial-liquid ventilation, a procedure that is not harmful [16,17].…”

Repeated subretinal surgery and removal of subretinal decalin is well tolerated - evidence from a porcine model

“…In contrast, previous studies using Healon to induce RD demonstrated massive histological changes [ 18 – 22 ]. Perfluorocarbon liquids (PFCLs) differ from Healon in that PFCLs can carry oxygen and carbon dioxide [ 23 ]. It is thus possible that some gas-exchange occurs across the subretinal decalin and nourishes the detached retina.…”