Some patients are left wondering if they have a ticking time bomb inside them. Others are upending carefully made plans for life-altering surgeries with long recovery times.

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Elective surgery does not mean optional surgery. It simply means nonurgent, and what is truly nonurgent is not always so obvious. Gerard Doherty, the chair of the surgery department at Brigham and Women’s Hospital in Boston, which began postponing elective surgeries on Friday, says surgical procedures can fall into one of three categories. About 25 percent of the surgeries performed at his hospital can be delayed without much harm. These might include joint replacements and bariatric surgeries for weight loss. Another 25 percent are for life-threatening emergencies that need to be treated right away: perforated bowels, serious heart problems, bones that have broken through the skin.

The last 50 percent are the tricky ones. These cases, Doherty says, have “some potential for harm to delay”; they might include cancer and problems in the blood vessels of the arms and legs. Brigham and Women’s is postponing some of these surgeries now on a case-by-case basis.

In Cruickshank’s case, for example, the initial bout of acute pain has passed. (That might have been when a gallstone got stuck.) He still feels “a little something” every now and then, and he worries that a flare-up might send him to the ER again. “Now I’m concerned,” he says. “If I go to the ER, are they going to have to turn me away and say, ‘Sorry, we have a bunch of coronavirus patients’?” The middle of a pandemic is a bad time to have a health emergency.

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For other patients, the canceled appointments have meant rescheduling long-anticipated and life-changing surgeries. Sherrie Kumm, 33, of Ellensburg, Washington, has epilepsy that causes her to have a petit-mal seizure nearly every day. She can’t drive. For the past six months, she has been preparing to have a small section of her brain removed to stop the seizures—a two-part surgery that would require a two-to-four-week hospital stay. She took a semester off from her online degree, took time off from her job at a school, and arranged for her mother to watch her two sons while she was hospitalized.

As late as Thursday, her doctor’s office had called to confirm the surgery. She had packed a suitcase, complete with the front-opening nightgowns she had specially ordered to wear in the hospital. On Friday morning, her doctor’s office called again, this time to postpone the appointment. “I had been mentally preparing and physically preparing myself and my children for six months,” she says. The sudden cancellation has been hard for her, and she’s unable to plan or reschedule her surgery for now.