MANAGEMENT OF COMMON REPTILE EMERGENCIES

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1 MANAGEMENT OF COMMON REPTILE EMERGENCIES R. Avery Bennett, DVM, MS, Diplomate ACVS Department of Clinical Sciences College of Veterinary Medicine University offlorida Gainesville, Florida USA Abstract: Though reptiles are slow with respect to metabolism and the effect of disease processes, reptiles present as emergencies as a result of acute injury, acute disease or an acute exacerbation of a chronic disease. Some of the common problems seen in reptiles presenting for emergency care will be reviewed. Key words: reptiles, calcium, seizures, dystocia, cloacal prolapse, bums,trauma Metabolic Bone Disease Metabolic bone disease (MBD) occurs secondary to calcium and/or vitamin D3 deficiency. It occurs most commonly in pet green iguanas, Iguana iguana, but is also a problem in other lizards and in chelonians on an improper diet. It is rarely seen in snakes because they eat whole prey and appear to require less ultraviolet (UVB) light; however it can occur in insectivorous snakes and snakes fed pinkies exclusively. It is believed that the optimum calcium:phosphorus ratio of the diet is between 2:1 and 1:1. Many commonly fed fruits and vegetables are high in phosphorus and low in calcium. Swiss chard, kale, beet greens, escarole, parsley, watercress, green beans, navy beans, turnip greens, broccoli, tofu, figs, and flowers such as roses, nasturtiums, carnations, and hibiscus have Ca:P > 1:1.. These should comprise /0 of the diet White grapes, romaine lettuce, dried apricots, pears, cauliflower, and tomatoes are moderately good sources of calcium and should comprise 10-20% of the diet. Vitamin D3 synthesis is poorly understood in green iguanas. Based on current information, the only means by which green iguanas are able to maintain adequate levels of vitamin 03 is by exposure to direct, unfiltered sunlight. Clinical signs in green iguanas are variable ranging from weakness and anorexia to tetany and seizures.. Slow gastrointestinal transit times, poor digestion, constipation and slow growth rate have been associated with MBD. In young growing iguanas, signs are most commonly referable to the skeletal system.. The maintenance of serum calcium concentration is at the expense of the bone. Spontaneous fractures can occur when bone has lost at least one third of its calcium content If calcium is deficient in the body, the process of bone mineralization cannot keep up with the deposition of organic matrix resulting in fibrous.osteodystrophy. The mandible is usually soft (rubber jaw) due to the lack of ossification. Eventually the pull of the tongue muscles causes caudal distraction of the mandibular symphysis with resultant lateral and/or ventral bowing of the mandibular bodies Proceedings Association of Reptilian and Amphibian Veterinarians 67

2 In adult iguanas which are no longer undergoing skeletal growth, signs of calcium deficiency are osteomalacia and those associated with hypocalcemia - twitching, tetany, and seizures. Because bone is a metabolically active tissue undergoing constant remodeling, there is a decrease in the concentration of calcium and phosphorus in the matrix of the bone. Seizures, muscle tremors, and tetany occur during hypocalcemia because of calcium's role in neuromuscular function. The most important parts of therapy are directed at correcting the underlying problems of diet and hypovitaminosis 03.. Studies of free ranging green iguanas have shown that they are strict herbivores and consume no animal material. Iguanas are hind gut fermenting animals which utilize vegetable matter for protein synthesis much like horses and rabbits. It is considered vital that captive iguanas be provided with exposure to direct sunlight. Iguanas should receive several hours of sunlight exposure weekly, though controlled $tudies on the exact time requirement are lacking. When iguanas are kept at cooler temperatures, digestion is inhibited which affects calcium absorption as well as the general health of the animal.,> its The patient's immediate calcium needs must be met in addition to improving the husbandry for long term maintenance.. Therapy is generally directed at providing calcium by injection and/or orally. Calcium glycerophosphate with calcium lactate (Calphosan, 50 mg ea/10 ml; Glenwood Inc., Tenafly, NJ) is administered at 1 mvkg lem. or intracoelomically (Lc.o.) every 1-7 d.. Calcium gluconate may be administered at 100 mglkg Lm. sj.d.-tj.d. in animals with tetany and seizures. In tients without tetany and muscle tremors, calcium gluconate(neocalglucon; Sandoz Corp.., East Hanover, NJ) is orally administered at 1 ml/kg sj.d.-b.i.d. Vitamin 03 can be administered orally or by injection though its benefit by either route is unknown.. Oral vitamin 03 is available from a variety of sources. It should be administered by injection at 200 IU/kglwk. Because most iguanas with MBD are anorectic, force or tube feeding is indicated. In patients with soft mandibles, tube feeding is preferred as there is less risk of causing iatrogenic fractures. Because of the delicate condition of the skeletal system, efforts mustbe made to prevent fractures. Synthetic salmon calcitonin (Calcimar, 200 IV/ml; Rhone-Poilenc Rorer Pharmaceutical, Inc., Collegeville, PAl has been used in green iguanas with MBD to inhibit further resorption of calcium from bones. It is times more potent than human calcitonin. It must not be given to patients with hypocalcemia as it can exacerbate the hypocalcemia resulting in death. Normal plasma calcium concentrations in green iguanas range from mgldl (the higher end is generally found in females producing eggs). Treatment with salmon calcitonin should be delayed one week in cases where plasma calcium levels are unknown. During this time the lizard should be treated with oral and parenteral vitamin and calcium supplements. Salmon calcitonin is administered at 50 IU/kg once weekly generally for only two treatments. Seizures In addition to occurring with MBD, seizures and muscle twitching may be seen with toxin exposure, viral diseases such as inclusion body disease of boid snakes, and other central nervous system disorders. Ivermectin is toxic to chelonians. It produces a flaccid paralysis which is potentially fatal.. The patient should be intubated and ventilated to prevent asphyxia. Some patients recover with supportive care but the drug binds irreversibly and it may take many days for resolution of clinical signs Proceedings Association of Reptilian and Amphibian Veterinarians

3 Dystocia Dystocia can be difficult to diagnose in reptiles. The time from breeding to egg laying or parturition cannot always be accurately predicted. Many reptiles behave normally even though they are unableto pass theireggs orfetuses. In many species the gravid state is easilydiscerned clinically; however, in very large squamates, viviparous reptiles, and chelonians the presence of eggs or fetuses may be difficult to determine. Tenesmus or cloacal prolapse may be indicators of dystocia. Some reptiles become depressed and anorectic, but this behavior is normal during gestation in many species, complicating accurate diagnosis. Radiographs and ultrasound may be helpful in arriving at an accurate diagnosis. The presence of malformed eggs/fetuses, abnormally positioned eggs/fetuses, or nonviable fetuses are indications for intervention. With green iguanas, anorexia for over one month is often considered cause for concern and an indication for medical intervention. In cases where parturition begins but stops, treatment for dystocia should begin within 48 hr. Physical manipulation can relieve dystocia in species where individual eggs/fetuses can be palpated and gently manipulated to the cloaca. This is most commonly done in snakes. The procedure carries risk of egg rupture, oviduct rupture, and even death has been reported. Oxytocin at IU/kg Lm. or Lc.o. has been used with success. A second dose may be given min later if no effects are observed. Temperature will influence the effectiveness of this hormone and the animal must be maintained at its preferred temperature. Oxytocin appears to be mosteffective in chelonians (about 90%) and less effective in snakes and lizards (about 500/0). Because oxytocin stimulates oviduct contraction, it should not be used in reptiles with active contractions. As with other species, it can result in oviduct rupture if used in cases of obstruction. Percutaneous ovocentesis is used in oviparous reptiles to collapse an egg that is otherwise unable to pass.. Reptile eggs are generally not hard but are more leather-like. A needle is inserted through the ventral coelom into the egg and its contents aspirated. The egg is collapse making it easier for the reptile to pass. A large gauge needle is used to allow the thick egg contents to be aspirated but this also introduces more risk of yolk contamination of the coelomic cavity. Surgery should be performed if the egg is not passed within 48 hr. Surgery is indicated for relief of dystocia if the above fail, if there is an obstruction that cannot be relieved, or if there is prolapsed, devitalized oviduct tissue. The prognosis for return to reproductive viability following salpingotomy is good to excellent. Cloacal Prolapse The colon, penis or hemipenes, oviduct, or urinary bladder may prolapse through the vent in reptiles. In some cases it can be difficult to determine what tissue has prolapsed. The colon and oviduct have a lumen which should be identifiable. The bladder and penis/hemipenis do not have a lumen; however, the penislhemipenis is very thick and fleshy while the bladder is very thin walled and usually contains fluid, urates, mucus, etc. The oviduct can usually be distinguished from the colon if feces are voided. Also, the wall of the oviduct has fine longitudinal striations which are not present in the colon wall. If doubt still remains, contrast radiography can be used to determine if the structure is gastrointestinal or genital in origin Proceedings Association of Reptilian and Amphibian Veterinarians 69

4 The tissue viability must be assessed and will affect treatment Nonviable tissue must be excised. This often requires a celiotomy to access the organ. The penis or hemipenis is not a vital structure and can be excised without consequence. Mattress sutures are placed at the base of the penis/hemipenis and the dead organ is transected distal to the sutures. The stump is replaced within the cloaca. If the tissue is viable, the prolapse is reduced and the organ returned to its normal location. In chelonians, the penis lays cranial within the cloaca. In squamates, it is caudally directed into the tail. If the organ is simply replaced within the cloaca, the incidence of recurrence is much higher. If the colon is prolapsed and the tissue appears viable, it is reduced and a blunt probing is used to gently push the tissue back into the coelomic cavity toward the left side in the area of its original location. If the tissue is necrotic a resection and anastomosis must be performed. In squamates this is performed through a celiotomy. Some colon prolapses in chelonians can be excised by exteriorizing viable tissue through the cloaca, placing a stent in the lumen, transfixing the colon to the stent, placing mattress sutures circumferentially, and excising the nonviable tissue tal to the sutures. This creates an end-to-end inverting anastomosis of the colon. If viable tissue cannot be exteriorized, a celiotomy is performed. Oviduct prolapse is treated much like prolapse of the colon. All reptiles have a bicornuate reproductive tract. If one oviduct is prolapsed and devitalized, it is best to perform a celiotomy to remove the necrotic oviduct and its associated ovary. If the ovary is left without an oviduct, the risk of yolk peritonitis is great. Male and female reptiles with one side of their reproductive tract removed are considered reproductively viable. Thermal Burns Though reptiles are poikilotherms and require heat supplementation, thermal burns occur. Bums on the ventrum are often associated with heat rocks having non"'uniform heating coils. Radiant heat lamps cause bums if the reptile is allowed to get too close to the lamp. A thermometer should be placed under the heat source at the level of the dorsum of the reptile to assure that the temperature is not excessive. Thermal burns in reptiles are treated as they are in other species. They have a tendency to become colonized by gram negative organisms. Frequent debridement and irrigation with antiseptic solutions are required in the early phases of treatment Wet-to-dry bandages are applied to aid in wound debridement With diligent and proper wound care, most thermal bums heal with little consequence. Reptiles have an amazing ability to heal by second intention given the chance; however, patience is a must as it can take many months for wounds to granulate and epithelialize. These principles apply to wound care and management of other types of wounds in reptiles as well. Shell Fractures and Dog Chew Injury Chelonians presenting with shell fractures are not always treated with patches. The wound must be assessed prior to making a decision regarding whether the wound should be closed or left open to heal by second intention. If the wound is acute, relatively clean, and minimally contaminated as with a laceration in a mammal, it can be closed primarily using patching materials such as epoxy glue and fiber glass cloth. If the wound is old, has necrotic tissue, or is Proceedings Association of Reptilian and Amphibian Veterinarians

5 contaminated, it should be treated as an open wound as described above. Many clinicians offer a poor prognosis for recovery if internal structures are visualized. This is not necessarily warranted. With proper wound care, even deep shell lacerations into the coelomic cavity can be successfully treated. The wound will granulate and scar in. The scar will contract and approximate the normal curvature of the shell. Eventually, the scar tissue will become cartilaginous and even ossify. Dog chew injuries should be treated as open wounds. Systemic antibiotic therapy is indicated in the management of all open wounds. Shell fractures associated with paraparesis and dog chew injuries where the pectoral musculature is destroyed carry a guarded prognosis for recovery. Abscesses Reptiles tend to form caseous rather than liquid pus. Some abscess will have a liquid component, however. Most isolates are gram negative. It is better to culture the tissue capsule of the abscess rather than the pus itself. In some cases, it may be advantageous to excise the entire abscess and capsule en bloc. If this cannot be accomplished, the abscess is treated as an open wound. Conspecific aggression often results in bite wounds that become infected. Serratia spp are commonly isolated from iguana bites. Oral abscesses are also common and generally are managed as open woundso Treatment includes systemic antibiotics and topical wound cares Dyspnea Respiratory distress in reptiles may be secondary to an obstruction, tracheal mass, pneumonia, and lung worm infections. Iguanas belonging to people with long hair may attempt to ingest the hair which then becomes entrapped and encircles the glottis preventing it from opening. Relief occurs rapidly after the hair is removed. Tracheal chondromas have been reported to cause a rather acute onset of dyspnea and open mouth breathing in ball pythons. It appears that the snake compensates to a point and then demonstrates dyspnea after a sizable mass had developed 0 Dyspnea and open-mouth breathing are common clinical signs in reptiles with pneumonia. A tracheal wash is performed for culture and sensitivity, cytologic evaluation, and parasitologic examination~ Rhabias spp and pentastomid worms can infect the lung and cause a chronic pneumonia non-responsive to antibiotic therapy. Larvae or eggs are frequently observed in a wet mount preparation or stained cytologyo The oral cavity is also examined for evidence of infectious stomatitis which may have initiated the pneumonia. Treatment includes appropriate husbandry and systemic antibiotics and/or anthelminthicsg Some reptiles present with stomatitis without pneumoniao The oral cavity of reptiles is usually pale pink and relatively dryo With stomatitis the mucosae are dark pink, red and appear inflamed. There will usually be excessive production of mucus giving the oral cavity a wet, tacky, gooey appearances Cultures of the oral cavity should be obtained prior to treatment. Treatment includes debridement of necrotic tissue, irrigation with an antiseptic solution such as 0.050/0 chlomexidine, and a topical antibacterial medication. Stomatitis is usually secondary to improper husbandry which must be addressed Proceedings Association of Reptilian and Amphibian Veterinarians 71

6 Hypothermia Reptiles kept outdoors during the spring and fall may be subjected to unusually cold temperatures when a front moves ina Such reptiles are often comatose with no perceptible heart beat Unless the animal is frozen, gradual warming will often return them to a normal state. Most of these patients fully recover in a couple of hours with no long term complications. Euthanasia Assessing death in reptiles is very challenging. There are many reports of reptiles being placed in the cooler for necropsy only to find them alive and moving when pulled out for a post mortem exams In some situations a reptile's heart may only beat once every few minutes. During hibernation, the heart may only beat once an hour or less. The heart of a decapitated reptile may continue to beat for hours. E following the administration of large doses of euthanasia solution the heart may continue to beat for hours. Because reptiles do not have a diaphragm and can breathe without negative intracoelomic pressure, opening the thoracic cavity does not assure deathe Potassium chloride (KCI) (Sandoz Pharmaceuticals, East Hanover, NJ) is an effective cardioplegic. The reptile is given a proper dose of euthanasia solution producing a comatose stateo The heart is then stopped using 2mEqlkg (1 ml/kg, KCI concentration, Lvs or LCa) The heart stops rapidly following the administration of the potassium~ REFEREN ES Burgmann PM, McFarlen J, Th.ssenhausen KII 1 3D Causes of hypocalcemia and metabolic bone disease In Iguana Iguana" J 8m Exotic Anim Mad, 2(2): Maciel' DR Reptile Medici... and Surgery:we Saunders Co, Philadelphia, PA Proceedings Association of Reptilian and Amphibian Veterinarians