Respiratory rate and tidal volumes were measured in dogs submitted to en bloc thoracotomy. Before the operation, a tranquilizer, acepromazine maleate was injected intravenously, as a preanesthetic. An ultra-short-acting barbiturate, thiopental sodium, was used as a general anesthetic. An endotracheal tube was inserted and the automatic mini-respirador Narcomatic, with intermittent positive pressure, was used. A radical thoracotomy technique was developed. The minute volume, respiratory rate and tidal volume were measured as follows: just before anesthetic induction (T0); at end of surgery (T1); 24 hours (T2) and 7 days after surgical period (T3). Local anesthesia of intercostal nerves of the thorax, dose of the thoracotomy, were also performed on dogs in group II at end of surgery (T1) and 24 hours (T2) after the surgery. The en bloc thoracotomy did not interfere with ventilation in the mecanic respiratory.
canine surgery; thoracotomy; tidal volume; minute volume
