Veterinary technician Cindie Erickson, left, monitors vital signs on Lucy, an obese orangutan at the National Zoo, as veterinarian James Steeil examines her Thursday in Washington. (Linda Davidson/The Washington Post)

The doors to the treatment room swung open, and the patient was rushed in by eight attendants in surgical masks. The lead doctor wiped sweat off his brow with his sleeve and the team rolled the 42-year-old female onto the examining table.

Her name was Lucy. She was overweight, had straw in her hair and, while anesthetized, had started coughing in the van on the way to the hospital. James Steeil, the doctor, listened to her chest with a stethoscope.

There was a canister of pepper spray on the wall nearby, as a precaution.

The patient was an ailing 185-pound orangutan, and on Thursday morning, she was taken to the veterinary hospital at the National Zoo.

Lucy, a diva among the six “orangs” in the Great Ape House, detested exercise.

Lucy is the National Zoo's oldest orangutan. Go behind the scenes at the zoo’s veterinary hospital as vets run tests dealing with her heart, lungs and weight. (Jason Aldag/The Washington Post)

Instead of using the zoo’s overhead climbing cable to swing on, she preferred sitting by her enclosure window, basking in the attention of her fans.

Her lifestyle had left her with a weight problem.

Zoo nutritionists had tried a diet, and she had lost a few pounds. But lately her wheezing, whenever she exerted herself, had grown more pronounced. And the zoo veterinarians had become worried.

So at 8:30 a.m. Thursday in the ape house, they anesthetized Lucy with an arm injection and drove her to the hospital for a checkup.

Over the next two hours, veterinarians and technicians poked and prodded her, took samples of her blood and stomach contents, looked in her ears, checked her teeth, took X-rays, did an echocardiogram, and tested her for tuberculosis.

They beat on her chest, in a procedure called “coupage,” to help loosen secretion samples in her lungs. And they gave her a shot near her armpit.

Left to right, animal keeper Becky Malinsky, Meredith L. Bastian, curator of primates; and nutritionist Erin Kendrick wait in a secure area as Lucy is moved into the exam room. (Linda Davidson/The Washington Post)

But they also were careful with her, putting socks on her giant, leathery hands and feet to keep them warm and covering her with a pink blanket for much of the procedure.

She coughed and wheezed as Steeil and fellow veterinarian Kendra Bauer inserted a tube into her trachea to help her breathe and to administer more anesthesia.

But for much of the exam, she rested quietly. Her chest, covered in coarse, rust-colored hair, rose and fell as she breathed, while a monitor in the corner displayed her heart rate, blood pressure and temperature.

“We hook them up just like they would a person,” said Steeil, an associate veterinarian at the zoo.

The doctors were most interested in her heart, lungs and weight. Female orangutans usually weigh around 100 pounds, the zoo’s Web site says.

As technicians conducted the tests, and one called out Lucy’s vital signs, Steeil studied her chest X-rays on a nearby screen.

“Her lungs should be much darker than this,” he said. “What we call it is ‘increased opacity.’ ” It can be caused by infection, allergies or heart disease.

“If she’s having issues with her heart, that can create fluid in her lungs,” he said. “The unfortunate thing is sometimes age” can cause it.

“That’s . . . why she’s probably wheezing, and why she’s having some difficulty breathing when she exercises,” he said. Which is rarely.

Lucy doesn’t hang with the other orangutans, said Becky Malinsky, a primate biologist at the zoo. The others literally hang from the zoo’s “O-line” cable as they travel from one part of their area to anther.

Lucy was born at the zoo in 1973, and originally she was named Nancy. She then was moved among four other zoos. At one point, she was renamed Lucy because the zoo where she was already had an orangutan named Nancy, Malinsky said.

She came back to the National Zoo 10 years ago.

She’s quirky and cunning, Malinsky said, and has a commanding presence.

“She’s very curious and very intelligent,” she said. “Even though I work very closely with her, I actually have the most difficult time reading her sometimes. . . . She’s thinking four steps ahead of us all the time: ‘How can I outsmart my keepers?’ ”

Her goal? “To be the boss,” Malinsky said.

Even so, Lucy seems to prefer human company, and one of her favorite foods is raw squash, with a little Texas Pete hot sauce.

Orangutans can be solitary in the jungles of Sumatra and Borneo, where they live, but are known to have food parties, called “feeding aggregations,” said Meredith L. Bastian, the zoo’s curator of primates.

At 42, Lucy is the zoo’s oldest orangutan. The animals can live into their late 50s.

After the X-rays, an outside veterinary cardiologist, Steve Rosenthal, conducted an echocardiogram on Lucy’s heart to check for problems. Her heart turned out to be in good shape. “For an orang of her age, it looks wonderful,” he said.

Then came a body-condition check. Zoo nutritionist Erin Kendrick felt Lucy’s spine, ribs, shoulders and hips to see how much fat she was carrying. Kendrick then scored her on a scale of one to nine — with one being emaciated and nine obese.

The best range was between four and six.

Lucy scored an eight, Kendrick said. “That is very high,” she said.

She needed to lose 25 to 30 pounds.

Kendrick said she didn’t include Lucy’s substantial belly in the score, because some animals can have fat bellies and still be healthy.

“That said, with her, it’s pretty obvious that she’s larger than she should be in the midsection,” she said.

Kendrick said she will stick with Lucy’s current diet, which has had some success. “It’s slow, but that’s what we want,” she said.

Lucy’s procedure ended about 10:30. They took off her socks, placed her back on to the gurney and headed to the Great Ape House.

She would stay on her diet, but the prospect of her using the zoo’s overhead cable for exercise would be nil, Bastian said.

“As much as it’s a wonderful thing and, yes, she would certainly benefit from the exercise, no, there’s no way we can get her to use it,” she said.