Liquid ventilation: A mathematical model of gas diffusion in the premature lung

The liquid ventilation (LI? technique was previously demonstrated to be (I valuable alternative to ordinary gas ventilation, particularly for newborn patients with severely distressed lungs. This work describes a mathematical perfluorocarbon (PFC) RM-101. The model was conceived in order to perform computer simulations of LV treatments. Its input parameters are tidal volume, respiratory frequency, oxygen and carbon dioxide tension in inlet PFC; its output data are the partial pressures of respiratory gases in the alveolar environment. Such values may be evaluated at any instant from the beginning of the treatment, in order to judge whether the therapy is able to meet the necessary conditions to arterialize properly the patient's venous blood The model also enables optimisation procedures to be defined and performed Quantitative results and graphs are supplied with reference to the simulation of LV applied to a preterm newborn of 28 gestational weeks. The main results point out that a relatively she-it duration of initial transients is attainable (200 to 240 s) and that blood arterialization is possible even with low oxygen tension in inlet PFC (29.7 kPa (223 mmHg)). (C) 1997 Elsevier Science Ltd for IPEM.