Sen. Kay Hagan was undergoing emergency eye surgery this morning in North Carolina.
The North Carolina Democrat, who is seeking re-election in a competitive race this year that Republicans have targeted as a pickup opportunity, was one of several senators to miss votes during the Senate's marathon sequence late Thursday.
Hagan spokeswoman Amber Moon said in a statement that the senator could not further delay departing for the medical treatment.
"Senator Hagan learned last week that she needs to undergo an emergency procedure to correct an eye condition that has worsened over time. In order to be present for work this week in Washington D.C., she delayed the procedure for as long as possible. However, she was not able to put it off any longer and was forced to leave last night to be in North Carolina for the procedure first thing this morning," Moon said. "The Senator will have a reduced schedule for a few days, but we expect that by the middle of next week she'll be fully recovered and back to full speed."
The Senate held a series of consequential votes on immigration, veterans' health and transportation before the chamber emptied for August recess. The next roll call vote is expected on September 8.