When one of the National Zoo's gorillas goes in for tests, it's not just standard operating-room procedure

By discovering heart disease early, echocardiograms have improved life for many a human; now Washington cardiologists are using them to help great apes at the National Zoo

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Question: How do you give a 448-pound gorilla an EKG?
Answer: With a lot of help.

It takes ten people to lift a sedated hulk named Mopie onto the operating table at the National Zoological Park hospital. Actually, the 24-year-old silverback is getting much more than an electrocardiogram. For over an hour he will be put through some of the most sophisticated heart tests we have, including an exam with a transesophageal ultrasonic scope, part of a Doppler echocardiograph machine.

The scope is a silvery L-shaped tube, hardly a foot long, and it costs $48,000. It is hand-built, with 64 crystals that can be fired in phased sequence to vibrate and thus send sound waves into the heart; the waves that bounce back are digitally reconstructed into a video image. Inserted into the esophagus next to the heart, the instrument provides an extraordinary picture of that organ, its valves, the aorta and everything else, as it pumps away. What we have here is a charming switch: the latest developments in human medicine being used to benefit animals.

"Cardiovascular disease is a significant problem in orangutans and gorillas, especially male gorillas," Dr. Richard Cambre, head of the Zoo's Department of Animal Health, tells me. "We've done all nine of our orangutans and now are working on the nine gorillas with echocardiograms, blood pressure exams and blood workups for cholesterol and lipid levels."

Though zoo animals live longer than wild ones as a rule-35 years is the average age for gorillas; the record is 54-they tend to develop heart trouble. No one knows just why. Is it hypertension? Arteriosclerosis? And why the high cholesterol? Though the Zoo provides the apes with a diet that is as close as possible to what they would eat in the wild, are the apes missing some trace item, some leaf or plant that they find in the lowlands of Zaire and Cameroon?

"These exams will give us baseline stats," Cambre says, "so we can follow them in later years. One thing: we don't have heart data on gorillas while they're awake. We might be able to train orangutans to accept a blood pressure cuff, but gorillas, I don't know."

They are not ideal patients. When Dr. Lucy Spelman, associate veterinarian at the Zoo, approached Mopie earlier this morning with the dart gun that would anesthetize him, Cambre recalls, "he figured out what was going on before she had a chance to fire the dart, though he'd never seen this particular type of equipment before. He knew what was going to happen to him." So Mopie produced from the source a gigantic handful of fresh gorilla manure and hurled it at Dr. Spelman, spattering her from hair to heels.

Undaunted, she is in the operating room working away on Mopie with the rest of the doctors when I arrive. She has wiped the stuff off her glasses but is otherwise concentrating on what she has come here to do. All in a day's work. The place has a pungent smell, somewhat like a bad case of halitosis. The vets tell me this is the normal scent of a gorilla when he's scared.

The dart, fired from an air pistol, goes into the leg muscles and puts a gorilla down in 15 minutes or so. After that he is kept under anesthesia with isoflurane gas, inhaled through a tube.

Now Mopie lies there with his silverhaired knees splayed and his giant paws curled like a sleeping child's fingers. A transducer clipped to his tongue tracks his blood oxygen saturation and pulse rate. His eyes are slightly open. The doctors bustle around him in their surgical masks and gloves, taking notes, checking the video monitors, moving probes about on his vast chest.


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