Electrocautery-Assisted Pleural Puncture for a Highly Reproducible Rat Pneumothorax Model.

OBJECTIVE

To describe a simple and reproducible rat pneumothorax model that is suitable for future sealant testing.

METHODS

Female Wistar rats (16 weeks) underwent left thoracotomy under mechanical ventilation. While the lung was inflated, the visceral pleural surface was cauterized using monopolar electrocautery with a ball electrode (coagulation mode, power 20%, 0.5 s), and then punctured with a 21G needle to a depth of 0.5 cm (Model E). The air-leak threshold airway pressure was measured using a water seal test. Pneumothorax and re-expansion were assessed by fluoroscopy, and pleural repair was evaluated histologically at 4 weeks.

RESULTS

Pneumothorax was induced in all rats (12/12) without procedure-related mortality. The air-leak threshold pressure ranged from 12 to 25 cm H2O (mean 17.3; median 16). All rats showed complete lung re-expansion at 1 week. Histological findings revealed fibrotic pleural repair (~100 nm thick) with preserved deep alveolar architecture.

CONCLUSION

Electrocautery-assisted pleural puncture provides a feasible and reproducible rat pneumothorax model for subsequent preclinical studies.