Evaluation of Elevent, a ventilator manufactured in Czechoslovakia for controlled ventilation during inhalation anesthesia in dogs]

Controlled breathing during halothane inhalation anesthesia was tested experimentally in fifty clinically healthy test dogs. In the first group the breathing regime was evaluated when a new Czechoslovak electronic ventilator Elvent was used in the course of 120-minute anaesthesia in 10 dogs. In the second group controlled ventilation was used in 40 dogs in the course of 180-minute anaesthesia with an administration of pipecurium as muscle relaxant. In the course of these experiments a total of 28 parameters was investigated to evaluate the effects of the given breathing regimes on the dog organism. An evaluation of the dynamics of changes in the target parameters indicated that the following model of ventilation programme with these parameters was the best: breathing rate 15-20 breaths per min., per-minute breathing capacity 1.5-3.5 l per min., breathing capacity from 0.15 to 0.25 l, inspiration length 0.8 to 1.2 s and twofold expiration length.