Mike Fisher, Randy Robitaille and Jason Spezza also scored for the Senators, who became the first Eastern Conference team to reach 30 wins. But the news wasn't all good as Alfredsson injured his hip and was forced out of the game early in the second period.
"If you have the choice, you always want to have him in the lineup," Vermette said. "He's our best player. He's been our best player this year."
Alfredsson, Ottawa's leading scorer with 29 goals and 60 points, took one shift in the middle period before leaving the game because of a hip flexor injury. He didn't return.
"I don't think it's too bad," Spezza said. "I think it's more precautionary, but hopefully he's not out for an extended period."
The Senators, who had lost two straight following a four-game winning streak, lead the East with 64 points.
Ray Whitney scored his 21st goal on a 5-on-3 advantage early in the third as Carolina's losing streak reached a season-high four games. The Hurricanes, who lost three in a row from Dec. 9-14, have dropped eight of 10 (2-7-1).
"It's gut-check time," captain Rod Brind'Amour said. "It's not easy when your confidence is a little shaken. You can tell that we're not making plays that maybe we were at the start of the year but this is the NHL and you've got to bounce back. We've got to find a way to do that."
Cam Ward allowed three goals within 2:23 as the Senators took a 4-0 lead 13:32 into the second period. Ward stopped 27 shots.
Ottawa outshot Carolina 14-7 in the first, a period in which the Senators easily could have scored more if not for a pair of shots off goal posts and a near miss by Vermette on a 2-on-1.
"They could have, and you look at it the other way ... we hit a post in the first period and we hit a post in the second period and you change that around and it's a completely different hockey game," Hurricanes defenseman Glen Wesley said. "We had some great opportunities and we didn't finish."
Alfredsson, who missed five games because of a hip injury last season, is the third member of Ottawa's top line of All-Star forwards to leave a game this week due to an injury.
Two-time 50-goal scorer Dany Heatley will miss next weekend's All-Star festivities in Atlanta because of a separated shoulder, an injury expected to sideline him for six weeks. Heatley was hurt in Saturday's 3-2 win over Detroit.
Spezza left Sunday's 3-1 loss to the New York Islanders for precautionary reasons after he was flattened by defenseman Freddy Meyer's open-ice hit. Spezza returned to the lineup for Tuesday's 4-2 loss in Washington.
Vermette opened the scoring 12:01 in when he outmaneuvered Wesley to put home a puck in the crease with 3 seconds remaining in the Senators' second straight two-man advantage. He added his second of the game -- his 10th overall -- at 12:12 of the second, between goals by Fisher at 11:09 and Robitaille at 13:32.
"You want to play well overall, but definitely when you have some offensive guys going down, you know you have to regroup as a team and try to find some offense throughout the lineup," Vermette said. "Some nights it's going to be some other guys because we know we don't have another Heatley in our lineup. We're comfortable with the depth that we have so that we can play well as a team and win some games, and we did that tonight."
Hedican returned after missing nine games because of a sprained right knee. Walker also returned from a knee injury that sidelined him for six games while Cullen was out for nine of 10 with a concussion.
- Yellow ribbons with a Canadian flag in the middle were painted behind both nets as thousands of the country's armed forces personnel took in the game on Canadian Forces appreciation night.
- Hurricanes coach Peter Laviolette used his timeout after Vermette's goal.
- Alfredsson needs one more goal to reach 30 for the fourth time in his career. Alfredsson scored 29 last season after reaching 30 in three of the previous four seasons, including a career-high 43 in 2005-06.