Resistance to pressure of the stump after mechanical stapling or manual suture. An experimental study on sheep main bronchus.

OBJECTIVE In a previous experimental study on 60 freshly slaughtered pig trachea, a statistically significant better resistance to pressure was found after mechanical stapling compared to hand suture. The objective of this study was to determine the resistance to pressure of a bronchial stump depending upon the closure technique (manual vs. mechanical) used in sheep 14 days after pneumonectomy. METHODS Pneumonectomy was performed on 30 sheep, which were alternatively closed either by a double-layer running suture at 90 degrees to the cartilaginous rings or with an automatic stapling device. Exactly 14 days after pneumonectomy, the animals were sacrificed and the trachea with the bronchial stump was retrieved. Sutures were placed under pressure until air leakage was observed. The air-leakage pressure was recorded digitally. RESULTS In both groups, there was no evidence of a bronchopleural fistula. As in the previous experimental study, mean values of air-leakage pressure revealed a large standard deviation in both groups (min. 0.16-max. 1.15 bar). Unlike the results in the first experiment there was no statistically significant difference between the two groups. CONCLUSIONS After 14 days, when a bronchial stump is considered to be healed, the resistance to pressure of a mechanical suture is equal to that of the manual suture.