Video showed the lawyers ransacking wards at the cardiac hospital, beating up staff and smashing equipment.
As panic spread, doctors and paramedics hid, leaving patients unattended, including those in a critical state.
Riot police fired tear gas to disperse the lawyers and more than 20 arrests were made. It took more than two hours to restore order, officials said.
The lawyers had been protesting over the alleged mistreatment of some of their colleagues by hospital staff last month.