ResMed Inc., San Diego, reported record net earnings of $4.8 million, or 31 cents a share, for the first quarter of fiscal 2000 ended Sept. 30, compared with earnings of $3.2 million, or 21 cents a share, for the same period a year ago. Net revenues for the quarter were $25.9 million, a 35 percent increase over last year. The results reflected increased sales in the domestic, Asian and European markets, officials said.

Mallinckrodt Inc., St. Louis, reported earnings of $38 million, or 53 cents a share, for the fiscal 2000 first quarter ended Sept. 30, compared with earnings of $32 million, or 43 cents per share, for the same period in 1998.

The company outperformed analysts' estimates, which put first-quarter earnings at 47 cents a share, and the company expects to surpass Wall Street's profit estimates for the full fiscal year, officials said.

Respironics Inc., Pittsburgh, posted net income of $4.3 million, or 14 cents a share, for the first quarter of fiscal 2000, ended Sept. 30. That compared with $6.3 million, or 19 cents a share, for the same quarter a year ago.

The results excluded the impact of charges totaling $14.7 million, or 29 cents a share, that related to the company's restructuring, officials said.

Net sales for the first quarter of fiscal 2000 were $80.6 million, a decrease of 7 percent, from the $86.4 million recorded in the same quarter last year.

Invacare Corp., Elyria, Ohio, reported net earnings of $14.1 million, or 46 cents a share, for the third quarter of fiscal 1999, ended Sept. 30, compared with earnings of $13 million, or 43 cents a share, during the same period in 1998. The company reported record sales for the third quarter of $223.3 million, a 10 percent increase from $203.4 million for the same period last year.

"We are extremely pleased with the strong sales and earnings performance of the company's European and Australasian operations as they continue to post double-digit sales and profit gains," said Mal Mixon, chairman and chief executive officer. Domestic sales, he said, "remained sluggish."