encountered a few stumbling blocks in its acquisition of the healthcare company Mallinckrodt Inc. The company yesterday announced that it had received a second request for information about the merger from the Federal Trade Commission about the sales of endotracheal tubes.

A Tyco release said the company sells less than $20 million worth of endotracheal tubes each year and it hoped the matter would be resolved quickly. The company expects to close the transaction by the end of September, as originally anticipated.

Shares in Tyco edged up one point on the New York Stock Exchange yesterday, closing at $55.75. Mallinckrodt was also up, gaining 1/16 to close at $46.125.