Emergency Surgical Kit
From Star Trek : Freedom's Wiki
The emergency surgical kit was a supplemental field kit in the 2260s, used when the medical tricorder and medkit's contents were inadequate for the treatment of major trauma. It presumably contained laser scalpels, protoplasers, and additional medications for sterilization, anesthesia, and pain relief.
In 2268, Dr. McCoy had Nurse Chapel beam down with an emergency surgical kit in a vain attempt to treat Kirk's critically injured wife Miramanee (TOS: "The Paradise Syndrome").