Dvorak, 33, and Rissmiller, 32, both are scheduled to become unrestricted free agents July 1.
Dvorak is joining his fifth team. He has seven goals and 14 assists this season.
Rissmiller has played mostly in the AHL the past two seasons.
Bergfors, a restricted free agent at the end of the season, has 11 goals and 18 assists this season.
Wideman, 27, has one more year on his contract, worth $3.9 million. He had 33 points (nine goals, 24 assists) and 33 penalty minutes while playing in 61 games for the Panthers.
Green was injured earlier this month when he took a puck to the head in a game against the Penguins. Poti has been battling a groin injury.
Hauswirth, 23, has 10 goals and four assists in 37 games with the South Carolina Stingrays of the ECHL this season.
Allen, who has one more year left on a contract that will pay him $2.9 million, will add depth to the Hurricanes' defense as they try to hold onto a playoff position in the Eastern Conference.
Samsonov, who has 10 goals this season, will be an unrestricted free agent this summer.
Later in the afternoon, the Panthers sent Chris Higgins to the Vancouver Canucks defenseman Evan Oberg to Florida and a 3rd round pick in 2013.
Coyotes get Klesla from Blue Jackets
Klesla, 28, a former first-round pick by the Blue Jackets and their last original player, has three goals and seven assists in 45 games this season. Klesla -- hampered by injuries the past two seasons -- has three years remaining on a contract that pays him
almost $3 million a year, through the 2013-14 season.
Byers, 25, has spent this season in the minors with the AHL Hartford and Springfield teams.
"When Ed Jovanovski [fractured orbital bone] got injured, we felt very vulnerable on our
blue line, especially in the defensive-matchup, penalty-killing
role," Coyotes general manager Don Maloney said. "We searched for what we
hoped was a top-four defenseman who could match up against good
players. This deal really came up today and it was a case where we
had to give to get."
The Blue Jackets and Coyotes both are fighting for spots in the
crowded Western Conference playoff race.
Upshall, 27, had 16 goals and 11 assists this season and 80
goals and 85 assists in 340 career games with Nashville,
Philadelphia and Phoenix.
Lepisto, 26, has four goals and seven assists this year and five
goals and six assists in 131 career games.
Upshall, making $2.25 million this year, is an unrestricted free
agent after the season. Lepisto, a restricted free agent after the
season, is making $800,000.
Ducks get Winchester, Perrault
Rangers trade for Mitchell
Mitchell, 26, has spent most of his time this season with the AHL Toronto Marlies. The Rangers assigned him to AHL Connecticut.
Bruins, Wild engage in minor trade
Khudobin went 4-1 with a 1.40 GAA in six
starts for the Wild as an injury fill-in the past two years. He has a .911 save percentage in 34 games for Houston in the AHL
Penner has five goals and 14 assists in 57 games for AHL Providence this season. Lehtonen is second in the Swedish Elite League in scoring this
season with 29 goals and 27 assists in 52 games. The native of
Finland played the previous two years with Providence
Information from ESPN.com's Pierre LeBrun and Scott Burnside and The Associated Press was used in this report.