Perflubron residua: 12 years following therapy

Administration of Drugs/Gene Products to the Respiratory System: A Historical Perspective of the Use of Inert Liquids

The present review is a historical perspective of methodology and applications using inert liquids for respiratory support and as a vehicle to deliver biological agents to the respiratory system. As such, the background of using oxygenated inert liquids (considered a drug when used in the lungs) opposed to an oxygen-nitrogen gas mixture for respiratory support is presented. The properties of these inert liquids and the mechanisms of gas exchange and lung function alterations using this technology are described. In addition, published preclinical and clinical trial results are discussed with respect to treatment modalities for respiratory diseases. Finally, this forward-looking review provides a comprehensive overview of potential methods for administration of drugs/gene products to the respiratory system and potential biomedical applications.

Perfluorocarbon Emulsion Contrast Agents: A Mini Review

Perfluorocarbon emulsions offer a variety of applications in medical imaging. The substances can be useful for most radiological imaging modalities; including, magnetic resonance imaging, ultrasonography, computed tomography, and positron emission tomography. Recently, the substance has gained much interest for theranostics, with both imaging and therapeutic potential. As MRI sequences improve and more widespread access to ¹⁹F-MRI coils become available, perfluorocarbon emulsions have great potential for new commercial imaging agents, due to high fluorine content and previous regulatory approval as antihypoxants and blood substitutes. This mini review aims to discuss the chemistry and physics of these contrast agents, in addition to highlighting some of the past, recent, and potential applications.

'Pseudo-calcifications': detection of perfluorocarbon residue on a computed tomography scan 15 years after liquid ventilation therapy at 3 months of age

Partial liquid ventilation using perfluorocarbons is a therapy that was once frequently used in paediatric populations for patients with severe respiratory distress. Perfluorocarbon is a non-toxic, insoluble and radiopaque vector through which improved gas exchange can occur. Two previous cases have been reported of persistent perfluorocarbon residua, identified on imaging years after receiving liquid ventilation therapy. We report a case of perfluorocarbon detection on a CT scan 15 years after liquid ventilation at 3 months of age, and propose the probable mechanism of its appearance. The importance of considering the imaging appearances of 'pseudo-calcifications' as a long-term sequela to perfluorocarbon liquid ventilation is emphasised.

Liquid fluorocarbon lavage to clear thrombus from the distal airways after severe pulmonary hemorrhage requiring extracorporeal life support (ECLS)

Massive pulmonary hemorrhage can pose a significant therapeutic challenge. Traditional methods of airway clearance using saline lavage and direct thrombus removal via bronchoscopy have limited ability to retrieve thrombi from deep airways. We report a patient on extracorporeal life support with massive pulmonary hemorrhage resulting in extensive alveolar and airway thrombus extending well beyond the proximal airways and the novel use of perfluorodecalin lavage to facilitate airway clearance and lung recruitment.

Clinical trial registration

None.

Efficacy of intratracheal instillation of a meropenem/perfluorochemical suspension in acute lung injury

Perfluorochemical (PFC) is theoretically a good vehicle for delivering biological agents to the lungs. This study was designed to investigate the efficacy of intratracheal (IT) instillation of meropenem using PFC liquid as a vehicle in a piglet model of acute lung injury (ALI). Eighteen piglets were injured with lung lavages to induce ALI, and randomly assigned to intravenous (IV) infusion or IT instillation groups, the latter using either PFC or normal saline (NS) as a delivery vehicle for meropenem. Blood samples were obtained at 0, 15, 30, and 60 min, and then hourly for 6 hr. Sera and extracts of lung tissues were assayed for meropenem content using high-performance liquid chromatography. We found that the IV group had significantly higher serum concentrations of meropenem during the first hour after dosing (P < 0.05). There was no significant difference between IT-PFC and IT-NS groups regarding changes in serum meropenem concentrations during the experimental period. Meropenem content in lung tissue was highest in the IT-PFC group, lower in the IT-NS group, and undetectable in the IV group (P < 0.05). The IT-NS group had the highest peak inspiratory pressure (P < 0.05), but there were no significant differences in other cardiopulmonary parameters among the three groups studied. In conclusion, meropenem can be safely administered to injured lungs by IT instillation in a meropenem/PFC suspension. Using PFC liquid as an IT vehicle to carry meropenem provides better pulmonary drug depositions than IV injection or IT instillation with NS in ALI.