EFFECTIVENESS OF EXTRACTED COW LUNG LIPID (CLL) IN INDUCING AND SUSTAINING NORMAL LUNG FUNCTION IN SURFACTANT DEFICIENT PREMATURE LAMBS

Abstract

Sterilized CLL was studied in premature lambs 132-134 days G.A. to determine if pre-breathing instillation could induce and sustain normal lung function for 2 days. CLL is a chloroform methanol extract of lavage of calf's lung containing 1% protein and flash autoclaved for sterility. We delivered 4 fetal lambs by hysterotomy, incubated them, took 10 ml of fetal lung liquid, instilled 100mg/kg of CLL in 10 ml of saline, and ventilated them immediately. Three control lambs were treated with 10 ml of saline. The lambs, sedated with nembutal, were managed using a clinical protocol. All CLL animals survived for 36-48 hours in good condition. Two control animals had a pneumothorax and 1 died at 21 hours. CLL treated lambs required mean airway pressures (MAP) of 10-15 cm H20 for 2 hours; average MAP was ≤10 cm H2O thereafter to maintain a PaC02 30-45. Control animals required an average MAP ≥20 cm H2O for 2 hours and 10-20 cm H2O thereafter. FiO2 requirements became <.4 by 7 hours in the CLL treated lambs. Control lambs required FiO2 >.4 until 21 hours age. Lavage of the lung at sacrifice revealed 49±10uM of alveolar surfactant in CLL lambs and 17±2uM in controls. CLL treatment before breathing induces and sustains normal lung function for 36-48 hours. This appears to be a surfactant preparation and protocol appropriate for a human clinical trial.