What is the ruling on prayer for employees in the surgical operations department of a government hospital, if they hear the call to prayer but cannot respond to it immediately due to their responsibilities, and some of them pray in congregation while others pray individually, even though there is a sufficient number?

Attending congregational prayers is an individual obligation for those who are able. If all the doctors can perform it together in the mosque, then it is binding upon them to do so. However, if it is difficult due to the patients' need for someone to stay with them, they should cast lots among themselves. Whoever's lot is drawn should leave, and the others remain. If there is a need for all of them to stay, then that is a sufficient excuse for not attending the prayer in the mosque.