INTRATRACHEAL PERFLUOROCARBON ADMINISTRATION COMBINED WITH MECHANICAL VENTILATION IN EXPERIMENTAL RESPIRATORY-DISTRESS SYNDROME - DOSE-DEPENDENT IMPROVEMENT OF GAS-EXCHANGE

Objectives: To test the efficacy of intratracheal instillation of a perfluorocarbon, combined with conventional mechanical ventilation, as well as to establish the dose response of this application on pulmonary parameters in adult animals with acute respiratory failure

COMPARISON OF VENTILATORY SUPPORT WITH INTRATRACHEAL PERFLUOROCARBON ADMINISTRATION AND CONVENTIONAL MECHANICAL VENTILATION IN ANIMALS WITH ACUTE RESPIRATORY-FAILURE

We investigated the efficacy of intratracheal perfluorocarbon (PFC) administration combined with mechanical ventilation to support gas exchange in adult animals with acute respiratory failure. These were compared with a similar group of animals treated with continuous positive-pressure ventilation (CPPV) with respect to respiratory parameters and postmortem lung histology. After lung lavage with saline, 18 adult rabbits were divided into three groups (n = 6 per group). All groups received conventional CPPV Additionally, one group received intratracheal PFC administration at a volume of 18 ml/kg (corresponding to functional residual capacity) (PFC group); another received 18 ml/kg of saline administration (saline group), and the last had no further treatment (CPPV group). All groups were ventilated for 3 h using 100% oxygen, with the same ventilator settings of tidal volume of 12 ml/kg, respiratory frequency of 30/min, and positive end-expiratory pressure of 6 cm H2O. In the PFC group, Pa(O2) increased from 67.2 +/- 11.4 to 424.2 +/- 14 mm Hg and remained stable for 3 h with well-preserved Pa(CO2) values. Only in the PFC group were significant decreases in airway pressures and increase in respiratory system compliance seen. In the CPPV group, Pa(O2) stayed around 60 mm Hg and Pa(CO2) gradually increased. PFC treatment with conventional mechanical ventilation in acute respiratory failure proved to be a successful supportive technique to improve gas exchange at low inflation pressures

Brain pharmacokinetics of lignocaine before and following intravenous perfluorocarbon emulsion infusion in sheep

1. Perfluorocarbon emulsions have potential medical applications, particularly as temporary oxygen carriers and are likely to be coadministered with other intravenous drugs. It is possible that perfluorocarbon emulsions may alter the disposition of other drugs in the body. 2. In the present study, we examined the brain pharmacokinetics of a 5 min infusion of 100 mg lignocaine in three chronically instrumented sheep before and after the administration of a new investigational perflurocarbon emulsion (Oxygent; Alliance Pharmaceutical, San Diego, CA, USA). 3. The rate constant for the blood : brain equilibration of lignocaine was larger after perflubron administration. This change could not be attributed to a change in brain blood flow and, therefore, may be the result of a change in the free fraction of lignocaine in the blood