Avaliação de técnicas de fisioterapia respiratória em modelo experimental de atelectasia em suínos recém-nascidos

Abstract

Objective : To compare the effectiveness of two techniques of respiratory therapy in an experimental model of atelectasis by bronchial obstruction in newborn pigs. Methods : 24 pigs were analgesiados, sedated, tracheostomized and mechanically ventilated. For the induction of atelectasis, artificial mucus was infused (ethylene oxide, Sigma-Aldrich , USA) using an infusion pump through the tracheal tube with the pigs in the lateral position and inclined to the 30th. Confirmation of atelectasis was a chest X-ray or by a pressure drop of oxygen in arterial blood. After the animals were divided into 3 groups: group 1 that received tracheal aspiration after 20 minutes of confirmation of atelectasis, group 2 underwent the technique of bag squeezing over tracheal aspiration and group 3 received vibration chest. To evaluate the effectiveness of techniques one second X-ray was done. To evaluate the changes during the procedures were performed arterial blood gases and pulmonary mechanics evaluation pneumotachograph before and after the induction of atelectasis immediately and 30 minutes after the procedure. Results : The mean percentage change in the PO2 was statistically detect significant between the groups (control: 97,80±37,33, bag squeezing: 166,75±68,63 e vibration: 104,41±45,45, p=0,0408), with improvement in oxygenation in the group undergoing the technique of squeezing bag. The remaining variables did not differ. Conclusions : the results suggest that the technique of squeezing bag is more efficient than manual vibration, but clinical improvement was not accompanied by detectable radiological improvement.