The Hippo with Toothache

by Lucy H Spelman

  Though we humans don’t have an air bladder, the gases in our bloodstream are subject to the same rules of physics. They move in and out according to pressure as well as chemical differences. The bends, also known as decompression sickness, occurs when scuba divers ascend too quickly. The air in their tanks has been compressed under pressure, ensuring that oxygen is delivered to the tissue as they dive down. As long as the diver ascends slowly, these gases will leave the body as the pressure equalizes. However, if the diver rises to the surface too fast, the gases will expand and form bubbles in blood vessels and tissues, which can cause painful tissue damage or even death. Trapped gas in the wrong place is a medical emergency—in any species.

  I decided to go for it. It sounded like a weird plan, taking tiny fish that look like seaweed into a hospital recompression chamber, but why not give it a try? I knew that our local hospital, St. Joseph’s, had such a chamber. In addition to treating dive accidents, it’s used in the treatment of several human diseases, including diabetes. People with this disease have very poor circulation in their feet and hands, and the increased chamber pressure helps improve oxygenation.

  For people with the bends, the chamber pressure forces gas bubbles in the tissues to dissolve and go back into the bloodstream, where the gas would then be slowly released out through the lungs. In the case of the sea dragons, I hoped for the same thing: the pressure would compress the excess gas out of the air bladder and allow it to be absorbed back into the bloodstream, and out of the body through the gills.

  When I called the hospital, the officials responded to my odd request by giving us an appointment for the next morning. Because running the chamber is time-consuming and expensive, they requested that the dragons share the chamber with several human patients. Grateful for the offer, and knowing the dragons couldn’t survive for much longer, I accepted.

  In order to keep the animals from staying at the surface overnight, we placed them in the container we’d prepared for their arrival. Using a plastic grate, we gently pushed the dragons down into the water and left the grate in place so that they would remain several inches under the surface.

  The next morning, Alex filled a portable acrylic tank with about twenty gallons of water and set it in a shallow Styrofoam container to which we added ice. We wanted the water temperature in the tank to stay relatively cool, around 60° Fahrenheit. He added an air stone attached to a small portable compressed air tank that would keep the water oxygenated. Carefully I slipped the animals into the tank and, with the help of Alex and three other biologists, slowly lifted the “travel package” into a van.

  An entourage of officials and public relations personnel met us at the hospital. Dragon paparazzi!! The local press wanted to film the event because it was so unusual; also because it helped highlight the fact that many of the procedures used in human medicine can be applicable to animals (in fact, many are first developed using animals).

  We set the tank and accessories on a cart and wheeled it down the hall to the chamber room. The chamber itself looked like a large steel bank vault, with pressurized windows on the sides, and several chairs. There were lots of curious looks as well as a few chuckles from the hospital staff and the human patients who were waiting for the procedure to start. Maybe the sea creatures would help make a long, boring procedure a bit more exciting for everyone. After the people had taken their places in the chamber, I walked in with the tank that held the dragons and set it near one of the windows so Alex and I could watch the procedure.

  The hatch was closed, locked, and sealed to deal with the pressure changes, and the process began. The pressure in the chamber would slowly increase, simulating a sixty-foot dive. The two animals in the acrylic tank gradually began to sink toward the bottom—precisely as we had hoped. There were a few thumbs-up gestures from the patients in the chamber. Phew, I thought, maybe we can save these little guys after all.

  For the next few hours, there was nothing for us to do but wait and hope the capillary beds inside the sea dragons could do their jobs. As we waited, we talked with hospital staff and the patients’ relatives about aquatic animal medicine. They were amazed at what was possible. We explained that we routinely take fish radiographs, perform surgery, and treat a range of different animals, from corals to sharks. We even use many of the same antibiotics and other drugs used in people. The range of success, however, is variable: aquatic medicine is still a new frontier in veterinary medicine.

  When time was up, we watched anxiously as the pressure in the chamber was slowly reduced. At about thirty feet, the sea dragons gradually moved upward, but not all the way. Holding my own breath, I hoped they would hold their positions. But as soon as the pressure returned to room conditions, the animals were back on the surface, struggling once more to stay upright. The procedure had not worked.

  Back at the aquarium, I went through all of the possible causes of the dragons’ problem and alternate treatments. After making a few phone calls and checking the literature again, I had no new ideas. I desperately wanted to save these special creatures, and not just because of all the time and effort (and money) we’d put into bringing them to Florida. With their arrival, our aquarium had joined a partnership known as Project Seahorse, an organization designed to call attention to the endangered status of sea dragons as well as sea horses.

  Before being shipped halfway across the world, our pair of dragons had been nurtured and fed in a special setting. We’d worked with an experienced collector in Australia who holds one of very few permits issued by the government to collect a limited number of specimens per year. These permits are given to discourage illegal collecting of adult dragons. Fishermen catch them not for food but as sources of “alternative” types of human medicine or as souvenir trinkets for sale in countless numbers of curio stores. It’s sad to think of these animals ending up in such shops. They are so beautiful in life.

  The collector is permitted to collect two types of dragons: one male weedy sea dragon, like the ones we received, and ten male leafy sea dragons. In aquarium lingo, we call them the “weedies” and the “leafies.” Sounds a bit like sports teams. The weedies have fewer appendages but tend to be more colorful, with yellows, blues, reds, and lots of decorative white spots. The leafies are the kings of camouflage, with ornate yellow and green fronds that blend in so perfectly with underwater vegetation that they can be hard to spot even when they hover right in front of you.

  Like sea horses, sea dragon males carry the eggs, though they are attached to their tails rather than inside pouches, and they can carry up to 250 eggs each. The wild fish are kept in a holding facility until they give birth, and then released back to the wild. When the eggs hatch, the young dragons, only about a quarter of an inch long at birth and practically transparent, are maintained in optimal water conditions, free of predators, and fed several tasty meals a day—sort of an aquatic bed-and-breakfast arrangement. Once they grow to about four inches in length, they are ready to be shipped. This complicated step requires all kinds of permits and paperwork, special containers, and logistical arrangements to ensure the shortest flight routes and times.

  —

  As a last resort, I decided to aspirate the air directly. Holding a flashlight behind each animal to illuminate the outline of the bladder, I identified suture lines between the bony plates and targeted these with a sharp needle. As a precautionary step, I applied a drop of ophthalmic antibiotic liquid before and after the procedure to help reduce chances of infection. Immediately after the procedure, the fish looked better: both could dive down in the water, if very slowly. I began to hold out a little more hope.

  Since the dragons hadn’t been eating, we started tube-feeding them mashed-up brine shrimp, hoping to keep their energy levels up. This procedure in itself required creative thinking. We needed to find a tiny flexible tube to place directly into their stomachs while gently holding the fish out of water. I finally found a long catheter, the kind used for spinal taps in humans, that worked perfectly.
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br />   A day after the aspiration procedure, they were still alive. We continued to give them antibiotic injections and tube-feeding. Maybe we were finally on the right track. But to my frustration and sorrow, both animals died two days later.

  The next step was a painstaking review of our transport procedures. Though we couldn’t prove it, my best guess was that the dragons did suffer from supersaturation of their water with oxygen at some point during transport from Australia, possibly during the stopover in Los Angeles, where the animals were repackaged. In preparation for the flight to Tampa, the last leg of their long trip, a fresh supply of oxygen was added to the transport box. Though intended to help, this step may have harmed the precious dragons. We made a number of improvements for the next shipment, including sending one of our biologists to LA to help with the repackaging.

  Despite losing both animals, some good things came of this effort. Although the recompression chamber did not save the fish, its use generated a lot of discussion among my veterinary colleagues about alternative treatments as well as about exhibit design. In the long run, this exchange of information increased our collective understanding of sea dragons, including their health care.

  More important, the pair of sea dragons in the next shipment arrived in excellent condition; indeed, they thrived, and we were able to open the new exhibit to great reviews. Visitors were fascinated by the creatures’ exotic appearance. We have since acquired leafies as well as weedies, and their protection in the wild has improved. These eye-catching fish continue to be among the most popular animals at our aquarium.

  ABOUT THE AUTHOR

  Though she grew up in the Midwest, Ilze K. Berzins chose to pursue a career in marine biology. She attended Stanford University, earning her BS and MS degrees in biology, and then earned a PhD in zoology from the University of California, Berkeley, with an emphasis on marine invertebrates and behavioral ecology. While assisting with field studies on parasitism in shorebirds, Dr. Berzins became interested in combining aquatic biology with veterinary medicine. She attended veterinary school at the University of California, Davis, and completed an externship at the Minnesota Zoo. After several years in private practice, she enrolled in a three-year fellowship program in comparative pathology at the Johns Hopkins Medical Institutions, and then returned to Minnesota to set up a consulting business in exotic and aquatic animal medicine. For the past ten years, she has served as veterinarian and vice president of biological operations at the Florida Aquarium, where she oversees animal health, husbandry, conservation, research, and dive programs, and is responsible for over fifteen thousand animals, including small mammals, birds, reptiles, and fish. The motto “Leap and the net will appear” has kept her moving forward on an unusual and exciting career path.

  Amali’s Example

  by Lauren Howard, DVM

  “HELLO. MY NAME is Lauren Howard and I’m calling from the zoo. I was wondering if I could speak with one of your orthopedic surgery instructors? No, I’m not a patient. You see, I have a giraffe with a leg problem. . . .” Click. “Hello?”

  “Hi, I’m a veterinarian at the Houston Zoo. I have a giraffe with a leg problem and was hoping I could talk to one of your surgical instructors. Yes, I know you don’t treat animals. I should try calling the zoo? No, I’m from the zoo. . . . Hello?”

  Working at a zoo that’s next to one of the country’s leading medical centers has its advantages. At least that’s what I thought when I started calling around looking for advice to help manage my current patient, a young giraffe with a front-leg abnormality. The Texas Medical Center includes two universities and dozens of medical facilities spread out over several blocks across from the zoo. As I dialed medical schools and teaching hospitals, I flipped through a stack of sports-medicine catalogs on my desk, trying to picture a fashionably colored, hinged knee brace fitting onto our patient’s scrawny, three-foot-long front leg.

  After enduring a variety of on-hold musical selections and repeating myself several times to several medical receptionists, I finally found the contact I was looking for. A human orthopedic surgeon called me back.

  “What was this about a giraffe?” he asked kindly.

  “Well, she’s about four months old. Her hip was dislocated the day she was born, and while she’s been recovering from that, she’s developing secondary problems in her front legs. I think she needs a support brace for her leg, but nothing we have is working. I’ve been through dozens of sports-medicine catalogs but I don’t think a human brace will fit right. I’ve got her leg measurements. Do you know of anyone who might be able to make a custom—”

  “I’ve got just the guy for you,” he cut me off. “His name is John Fain; let me get you his number.”

  With one more phone call, I arranged for John to come down to the zoo and join us in our ongoing efforts to get Amali walking normally for the first time in her life.

  Born one cool fall morning, Amali did not stand up right away, and her mother accidentally stepped on her, dislocating the calf’s right hip. Before the newborn giraffe had a chance to feel the dirt beneath her baby-soft hooves, she found herself in a veterinary specialty hospital. A team of orthopedic surgeons put her leg back in its socket. Lying on the gurney with her head up, Amali surveyed her surroundings as we wheeled her down the halls of the hospital. She seemed to take it all as a matter of course. She had no way of knowing the first few days of life should be any different.

  Amali means “charm” in Swahili, a fitting name for this lanky newborn. With her large brown eyes and velvety soft muzzle, our new Masai giraffe calf charmed everyone who met her. Unfortunately, the Hebrew translation of Amali, “result of a long struggle,” turned out to be a better description of this spirited little addition to our giraffe family.

  After the surgery, the giraffe’s hip healed only partially. Because she needed extra support and special care, she was hand-raised on bottles of goat milk. As she grew, Amali could walk but favored her rear leg. As a result, she bore more weight than normal on her front legs, and gradually developed joint problems. Amali’s right front leg, in particular, bent out at her knee joint whenever she put weight on it, angling to the side. Because this leg required extra support, we created a makeshift splint using large PVC piping, cut in half and padded with lots of bandaging material. This is a technique used routinely by equine veterinarians for young foals with similar leg deformities. Foals, however, rarely weigh more than 80 pounds and have shorter, more manageable legs. At this point, in early January 2005, Amali weighed about 170 pounds.

  Each morning, Amali’s keepers (and our largest veterinary technician, Grant, when we could coax him into it) would hold her as still as possible in a corner of the giraffe barn, while they sweated profusely and tried not to let her slip out of their grasp. Often we’d get the padding in place for the PVC splint, only to have our willful giraffe send the gauze and six feet of cotton wrap flying through the air like confetti at a lively New Year’s Eve party. To the early morning zoo visitor who happened to catch sight of the strewn bandages through the barn window, it must have looked like quite a fun party indeed. In fact, the procedure was becoming increasingly difficult and even dangerous.

  —

  “Erica in the clinic to Dr. Lauren. Your specialist is here.” Our hospital clerk’s voice crackled over my radio. A few minutes later I found John Fain at the zoo clinic, already deep in conversation with a member of our staff, completely at home among the cacophony of smells and sounds common to a zoo hospital. Over the phone a month earlier, John had explained that he was an orthotist and prosthetist, meaning that he designs prosthetic limbs and support braces for his human patients. A self-confessed animal lover and farm boy, John was the perfect fit for our situation. In his standard-issue blue hospital scrubs and shiny white sneakers, he made a cheerful first impression. He’d brought an assistant with him and a shoulder bag of equipment, as well as a digital camera held together with several pieces of duct tape.

  At the giraffe barn, I in
troduced John and his assistant to the keepers and supervisors, who were all eager to help with the creation of the leg mold. The best way to design a well-fitting brace, John had told us, is to make a mold of the leg, which would be used to make a solid model of the leg; then a brace could be made to fit the model. To make the mold, the leg must be placed in a special plaster cast material and held motionless for five to ten minutes while the plaster dries. This is a fairly simple undertaking, I’m sure, when it’s performed on cooperative human patients who understand what is being done and why. It’s true that John’s patients sometimes included small children, as well as residents of the state’s prison system who may not always have been completely cooperative. Still, I’m confident that none of his previous patients measured up to Amali.

  Now 180 pounds and almost six feet tall, Amali was testing the limits of our staff’s ability to restrain her manually. With two people on either side of her and one in front, we pushed her back against a wall of the barn where we could control her a little more easily. It took three more people to extend her right front leg and hold it straight so that John could slide on a protective sleeve, then roll the mold plaster around her leg. Once the mold was in place, we did our best to keep Amali from kicking or bending her leg—or worse, sagging to the ground, as she often did when she realized she was trapped.

  Minutes ticked by as we made nervous jokes. The sweat of the people on the top of the Amali-pile trickled down onto the backs and heads of those unlucky enough to be on the bottom. After what seemed an eternity, John snipped the mold off and disappeared into the hazy afternoon with our hard-won prize.

  We’d known all along that we could not reverse the source of the problem—the damage in Amali’s right hip. Even at the tender age of five months she was too heavy to undergo another hip surgery or hip replacement. Instead, we’d focused on the things we could fix: her front legs and right knee. By protecting these joints, we could give Amali a chance to walk without pain. Masai giraffes can grow up to fourteen feet and weigh 1,200 pounds. It was hard to imagine our little patient ever reaching this size; yet, if she did, the stress on her damaged hip would be severe.