Karen Austin, 41, Kmart's chief information officer since April 2002, will permanently assume the company's marketing responsibilities following the June 13 departure of Barbara Firment, a Kmart rep said. Sources said Kmart dismissed Firment, 51, svp of advertising, sales and in-store presentation. Firment could not be reached. Kmart spent $270 million on ads in 2002, according to TNS Media Intelligence/ CMR. The change will not affect Kmart's agency relationships, the rep said. Omnicom's TBWA\Chiat\ Day in New York handles broadcast duties; Meridian Advertising in Troy, Mich., works on print.