Joan Rivers -- Clinic Overhauls Procedures to Avoid Repeat Tragedies

The clinic where Joan Rivers' throat procedure turned deadly ... just filed a plan to make a slew of major changes to avoid getting shut down by the feds.

According to docs obtained by TMZ ... Yorkville Endoscopy is responding to flaws found by the Department of Health and Human services ... by making several upgrades to its procedures.

Among the changes:
- Stricter procedures to credential physicians and observers who are admitted into operating rooms
- The clinic has to perform a full assessment of a patient's weight, allergies, and medical history before administering Propofol
- Supplemental oxygen should be routinely used and immediately available for patients sedated with Propofol
- Anesthesiologists must check vital signs at least every 5 minutes for patients sedated with Propofol
- Unscheduled drills to resuscitate patients using defibrillators/crash carts will be run 4 times a year

Most of the changes relate directly to problems the agency found at the clinic while investigating Joan's death. The Dept. of HHS has signed off on Yorkville's plan.

Yorkville officials had been given a January deadline to get this done ... or the feds could have closed down the clinic.