Abstracts: ASAIO Pulmonary Abstracts
A NEWLY DEVELOPED VENTILATOR PROTOTYPE FOR NEONATAL TOTAL LIQUID VENTILATION
Bagnoli, Paola1,2; Fiore, Gianfranco B1; Cattaneo, Enrico1; Monaco, Ario3; Acocella, Fabio3; Colombi, Roberto4; Costantino, Maria Laura1
1Dept. Bioengineering, Politecnico di Milano, Milan, Italy; 2Dept. Mechanical Engineering, Politecnico di Torino, Turin, Italy; 3Medical Veterinary Faculty, Università degli Studi, Milano, Italy; 4Surgical Pathology Service, Macedonio Melloni Hospital, Milan, Italy.
Aim:
Total liquid ventilation (TLV) seems to give significant advantages when preterm infants are concerned, but requires a dedicated ventilator to process the liquid perfluorocarbons (PFC). A new prototype volume-controlled, pressure-limited ventilator was developed and used for preliminary in vivo animal tests.
Methods:
The ventilator comprises a stepper-motor actuated double-piston system performing respiratory cycles and an uncoupled refresh circuit to achieve PFC filtration, thermostatting, oxygenation, and CO2 scavenging. A personal computer-based control system manages the two sub-circuits. The apparatus was tested using FC-77 in preliminary animal experiments on 4 New Zealand Rabbits (test lasting 4 hours) and 4 preterm lambs (gestational age 110±5 days; test lasting 6 hours). Control animals (n=2) were gas ventilated. At the end of each experiment, lungs were excised and processed for light microscopy in order to verify airway and lung parenchyma condition.
Results:
During TLV, adequate gas exchanges (arterial pO2=176 mmHg, pCO2= 45 mmHg) and blood pressure were maintained in the rabbits, while good oxygenation (pO2=94 mmHg) and moderate hypercapnia (pCO2=65 mmHg) were recorded during lamb experiments. Histological analysis showed neither atelectasis nor signs of inflammation in the TLV-ventilated animals.
Copyright © 2005 by the American Society for Artificial Internal Organs
