Their testimony Monday came during the first day of Kennedy's trial on misdemeanor charges of child endangerment and harassment, the New York Post reported.
Anna Lane said she tried to block the door at Northern Westchester Hospital after Kennedy said he was going to take his 2-day-old son Bo out for fresh air on Jan. 7.
As another nurse, Cari Luciano, blocked the elevator, Lane said Kennedy grabbed her left hand and twisted her arm.
When Luciano came to her aid, Lane said Kennedy kicked her. He lost his balance and fell to the floor with the baby in his arms.
Kennedy went down the stairs where he encountered two security guards. As he ran back up the stairs, he shouted "Do you know who I am?"
Prosecutors claimed that Kennedy kicked the nurse out of "bizarre desperation," the White Plains Journal News reported.
Lawyers for Kennedy have said the nurses overreacted and the incident was overblown.