Since Robert Udelsman, M.D., M.B.A., department chair and the William H. Carmalt Professor of Surgery, came to Yale in 2001 to lead the medical school’s Department of Surgery, the number of parathyroid operations has risen from about 30 a year to more than 350.

Most of these patients have primary hyperparathyroidism (HPTH)—one or more of the parathyroid glands in the neck begins to enlarge and produce too much hormone. These enlarged glands are called adenomas, and too much parathyroid hormone, or PTH, causes osteoporosis, kidney stones and other health problems. The adenoma needs to be removed, a procedure that usually requires general anesthesia and a stay of several days in the hospital.

Udelsman, however, has combined existing techniques with a simple but radical innovation—placing a laboratory machine to measure hormone levels inside the operating room—to turn this into an outpatient procedure.

“Patients can fly in on Sunday, get a place at the hotel and see us on Monday morning. Tuesday morning they come have surgery,” said Patricia Donovan, R.N., M.B.A., Udelsman’s clinical coordinator. “They return Friday that same week. They might explore New Haven, have their sutures removed … and fly back.”

Udelsman’s approach, which has been adopted by the other three endocrine surgeons on the team, involves several steps.

First comes pre-op preparation. In addition to the patient’s medical history, the team needs to know where the offending adenoma is located. Most people have four or more parathyroid glands, so figuring out which is the overactive one—or whether there is more than one—can be a challenge. Imaging studies help to localize it. Before the patients arrive for surgery, Donovan gathers relevant records, medical information and scan results, talking by phone with patients and their doctors to make sure that the surgery is appropriate for them.

In the operating room the uniqueness of Yale’s approach becomes evident. Instead of patients being placed under general anesthesia, patients receive a series of injections of local anesthetic in the neck. A small incision is made, the offending adenoma is removed and a blood test is done to check levels of PTH. But rather than sending the blood sample to a laboratory, the technician in the operating room tests hormone levels immediately. The surgical team waits only 12 minutes for the results—about a quarter of the time needed at other institutions, where waiting for results can take longer than the operation itself. If PTH levels have dropped sufficiently, the surgeons can be confident that they removed the adenoma completely. Then it’s time to sew up.

The entire procedure typically takes half an hour, and the patient goes home—or to the hotel—a few hours later, returning to the clinic in three days for a final follow-up visit. Complication rates are low, cure rates are about 98 percent and the surgery is cost-effective. But most of all, patients are satisfied.