Jeff Silva walked into his CT scan appointment at Good Samaritan Hospital in Brockton looking for answers. A biopsy and MRI had recently diagnosed his prostate cancer, and his doctors had ordered a CT scan with contrast to check that the cancer hadn’t spread anywhere else.

Contrast dye is usually administered to patients by IV or into an artery to light up vascular structures, making it easier for clinicians to see the web of detail inside the body. He was on the exam table about to begin the scan when he asked why he hadn’t received the contrast yet. The technician told him he wouldn’t be receiving it because of a shortage; the hospital was reserving the fluid for emergencies.

“I said, ‘Really? I would think this is kind of an emergency,’” Silva said. “I have cancer and want to make sure it’s nowhere else in my body.”

Hospitals throughout the state have been running low on contrast dye because of manufacturing shutdowns in a Shanghai GE Healthcare plant. Clinicians use the dye to look inside blood vessels and arteries, making things like CT scans, traumatic injury diagnoses, and cancer care more precise. Some health systems say they’ve had to find workarounds to protect limited quantities. Others say they’ve had to ration scans to conserve supply.

“For a radiologist who has been reading scans and always had IV contrast, to ask them to read without it, they will miss things,” said Dr. Eric Dickson, CEO of UMass Memorial Health. “It’s a horrible shortage. And it has significantly impacted operations. Ultimately we’ve had to do scans without contrast or withhold the scan.”

In his case, Silva’s doctor assured him if they weren’t sure of something, they would perform the scan again with contrast. While his doctors say they saw what they needed to, in the back of his mind, Silva worries they missed something.

Contrast dye is the latest shortage in a revolving door of supply issues, prompting an all-too familiar dance of conservation and prioritization that hospitals have perfected throughout the pandemic.

Problems have hopscotched from masks, gloves, and gowns at the start of the pandemic to other low-cost supplies and drugs that seem to change weekly. Saline infusions, used for hydration and to administer medications intravenously, have been in short supply, as well as sodium bicarbonate — used to care for critically ill patients, and syringes. The Red Cross warned of an “unprecedented blood crisis” for months, a problem that has seemed to resolve, though hospitals worry more shortages could come over the summer.

Dickson said most of the shortages were on inexpensive products that were neglected as companies prioritized making higher-margin items amid staffing shortages and production problems.

The sickest patients always receive what limited quantities there are. But he said the delays and shortages impact the next level of illness — patients sick enough to seek care but whose lives are not in immediate jeopardy.

“There has probably never been a worse time to be in that situation,” Dickson said. “We will always take care of the sickest patients, they will always go to the head of the line. They will always get the blood or IV contrast when there is a shortage. It’s the next level of acuity that is certainly much harder. That’s where there is the most impact.”

The contrast dye shortage has its roots in Shanghai’s latest COVID outbreak, when severe government restrictions forced the shutdown of General Electric’s production facility for contrast media.

According to the American Hospital Association, GE e-mailed customers on April 19, saying it was rationing orders. As of late May, the company said in a press release it had reopened at 60 percent capacity, and would reach 75 percent capacity within two weeks.

Dr. Paul Biddinger, chief preparedness and continuity officer for Mass General Brigham, said the health system was informed several weeks ago that it might receive only a quarter of its normal weekly shipments through August. The health system has since been told the issue could be resolved as early as July.

In response, affected clinical teams at MGB came together and developed prioritization guidelines. They centralized ordering, which used to be done by more than 35 different teams, and supplies were allocated as they arrived to ensure no product was unused or wasted. The health system has also purchased special devices that extract contrast from a vial in a way that the remaining dye can still be used.

The system has also asked clinicians if studies they ordered would still be effective without contrast, or if another imaging method such as an MRI would work. However substitutions are complicated because of prior authorization needs from insurers.

Biddinger said MGB had conserved its supply of contrast dye and has not had to pull back from offering it when clinically necessary. Yet the labor-intensive juggling act exacts a price.

“I would say it is harder for the health care system than it ever has been to ensure they can deliver the care that is needed right now, and is needed in greater volume than it ever has been,” Biddinger said.

Shortages have become so commonplace during the pandemic that Beth Israel Lahey Health uses a drug shortage task force to develop guidelines and recommendations on how to conserve and share resources. Efforts have ranged from conserving monoclonal antibodies and Paxlovid when supplies were low, to now dealing with contrast dye.

While the system has enough contrast dye for current patient care needs, Dr. Richard Nesto, chief medical officer of Beth Israel Lahey Health, said the system is conserving supplies for future weeks should the supply become more limited.

“These are individual decisions,” Nesto said. “Getting care in a [larger] health system may provide some flexibility resource wise, but it is tough.”

Some hospital executives said supply shortages occurred prior to the pandemic as well. But they are now increasingly common, said Dr. Brien Barnewolt, chairman and chief of emergency medicine at Tufts Medical Center.

“They can occur quite suddenly,” he said. “Usually we are able to afford a work around.”

Tufts Medical Center also said rather than delaying procedures or care, it has turned to alternatives to try to diagnose patients without using the contrast. The hospital hopes the contrast shortage will be resolved by late June.

Some health systems have turned to manufacturing their own products to get around supply strains. Biddinger said that last July, the health system had labs creating their own blood collection tubes, complete with a special chemical that prevents the blood from clotting. Staff had to work overtime and weekends to make them, and teams followed the all-too-familiar playbook of how to conserve in times of supply stress.

Despite lessons learned earlier in the pandemic to stock up on supplies, that isn’t always possible because of space constraints, cost, and the fact that drugs and sterilized supplies have expiration dates. Stocking up on supplies that are thrown out is cash down the drain.

“It’s hard to identify solutions in ways that don’t substantially increase the cost of health care,” Biddinger said.

Jessica Bartlett can be reached at jessica.bartlett@globe.com. Follow her on Twitter @ByJessBartlett.

Work at Boston Globe Media