About 13,000 union workers at five University of California medical centers, including the one in San Diego, began a two-day strike Tuesday.
Workers walked out after a judge approved the two day strike at the five largest University of California medical centers, including the centers in La Jolla and Hillcrest.
UC San Diego has canceled 120 surgeries and 350 radiology procedures over the next 48 hours administrators told NBC 7 San Diego.
UC hospital workers argue that the lack of staffing due to budget cuts has affected patient safety and their benefits.
Randall Johnson, an MRI technologist at UCSF, said employees are staging the work action over staffing levels, contracting out, pension contributions and other issues.
"We've been in negotiations for over a year and there's been no major movement on the core issues so we're at an impasse," Johnson said on Monday.
Hospital administrators expressed disappointment that the unions have used the strike as a tactic to get what they want.
"Patients shouldn't be in the middle of a labor dispute," Dwaine Duckett, UC's vice president for human resources said.
UC's Senior Vice President for Health Sciences and Services John Stobo estimated the strike will cost $20 million, which he said means that "there will be fewer dollars to support the education of medical students and residents to support programs to improve medical care."
A Sacramento County Superior Court judge issued an injunction Monday that limits the scope of the strike but said it could take place.