A Litchfield woman pleaded guilty Friday to pinching her baby's nose in an attempt to smother him.

Katie E. Lewis, 24, pleaded guilty to domestic assault by strangulation in Ramsey County District Court.

According to charges: On May 2, video surveillance at Children's Hospital in St. Paul captured Lewis pinching her 5-month-old son Carson's nose while covering his mouth. The incident lasted 45 seconds, and caused the infant to frantically kick.

Carson went limp in Lewis' arms. Medical staff rushed into the room.

The baby was admitted to the hospital the previous day. Lewis, a trained nursing assistant, told medical staff that the infant had stopped breathing, turned blue and lost consciousness on multiple occasions.

Lewis later told police that she was frustrated with her child-care responsibilities and had held Carson's nose and mouth closed multiple times, charges said.

Third-degree assault and child endangerment charges were dropped against Lewis as part of her plea agreement.

Lewis is scheduled to be sentenced Feb. 20.