Critical Care Facilities

Debilitated turtles are often dry-docked on a padded surface and kept moist by regular misting and placing Vaseline or water-soluble jelly (K-Y Jelly) on the skin and shell. Another option is to have recirculated, temperature-controlled, filtered water sprayed over the turtle to keep it wet and prevent drowning. Water levels in rehabilitation tanks should be adjustable to accommodate turtles with varying degrees of debilitation. Water temperature should be kept warmer for newly arrived and ill patients (26.5° C to 29.5° C) to improve their immune function and then slowly decreased as the condition improves. Prior to release, the turtle should be acclimated to current ocean temperatures. Sea turtles require specially designed, circular, nonabrasive fiberglass tanks with a filtration system and continuous flow temperature-controlled salt water. The entire life support system should be outside the tank because sea turtles will destroy and ingest almost anything. It is recommended to quarantine new arrivals. Outdoor enclosures with direct and indirect sunlight or full-spectrum lighting with a natural photoperiod are beneficial.

Diagnostic Procedures

An emergency minimum database should consist of a hematocrit, total solids, glucose level and, subsequently, a complete blood count and plasma biochemical panel. A blood sample for culture should be collected before initiating antimicrobial therapy. We recommend taking up to 0.5 to 0.8 mL of blood/100 g body weight in healthy patients and a reduced sample volume for debilitated patients. Lithium or sodium heparin are the anticoagulants of choice, because ethylenediaminetetraacetic acid (EDTA) will cause red blood cell lysis. Plasma is preferred over serum because clot formation is unpredictable and may cause changes in the chemical composition of the sample and the higher volume of plasma obtained.

The preferred blood collection sites in most sea turtle species are the dorsal cervical or occipital sinus.³² The head and neck should be extended and difficult to bleed turtles (e.g., green turtles) may be positioned with the head directed in a ventral position. The lateral jugular vein is an alternative site for green turtles and the femoral and interdigital vessels are alternatives in leatherbacks.³⁰ Lymph contamination may occur. Morphologic classification of blood cells⁶ and normal reference ranges for complete blood count, clinical chemistry, and plasma electrophoresis for the various sea turtle species have been reported.^4,10,15,21 (See http://accstr.ufl.edu/blood_chem.htm for ongoing clinical pathology reference values.)

Radiography is an important diagnostic tool used to assess sea turtle patients. Radiopaque materials such as barnacles should be removed from the shell before performing a radiographic study. Anteroposterior and lateral projections using a horizontal x-ray beam and a dorsoventral (DV) view should be performed. Larger turtles may require multiple radiographs to assess the entire coelom from a DV view. Digestive tract radiographic contrast procedures are often necessary to document intestinal obstruction, motility disorders, and foreign bodies. Normal transit times have been established for barium sulfate and nonionic iodinate contrast media.¹¹ Barium-impregnated polyethylene spheres may be placed in a food item, with subsequent serial radiography to assess gastrointestinal motility. Ultrasonography has been used to evaluate reproductive status and for general diagnostic purposes. Computed tomography (CT) is useful for assessing spinal and head injuries, free air pockets in the coelom, pneumonia, bronchiolar blockage, and internal fibropapillomatosis, although large sea turtles will not fit into most CT chambers. Normal skull CT anatomy has been established in loggerheads.² Open magnetic resonance imaging (MRI) is useful for larger sea turtles and normal MRI internal anatomic structures have been established in loggerhead sea turtles.²⁹ This technology has been used to detect internal fibropapillomas.⁹

Rigid endoscopy has been used for gender determination, evaluation of reproductive activity, exploring the coelomic cavity, organ biopsy for histopathology, and confirming the presence or absence of internal fibropapillomas. The technique has been described by Wyneken J, Mader DR, Weber ES, et al.³² Rigid and flexible endoscopy may be used to evaluate the cloaca, bladder, and distal GIT and to administer contrast media and enemas into the rectum. Rigid and flexible systems may be used to visualize the location of fish hooks in the esophagus. Flexible endoscopes may be used to evaluate the upper and lower GIT, trachea, bronchi, and anterior lung and for the removal of granulomatous material from the bronchial lumen.

Treatment

As noted, treatment of hypothermia, dehydration, hypoglycemia, and acid-base and electrolyte imbalances should be done in conjunction with starting other therapeutic agents. It is best to keep the sea turtle patient at its preferred optimal temperature zone while on therapy. Culture and sensitivity of various samples should be determined prior to starting antimicrobial therapy whenever possible. The front half of the body should be used for injections, especially when using nephrotoxic drugs. Anaerobic bacteria should be considered when deciding on a therapeutic plan. Several pharmacokinetic studies in sea turtles have significantly advanced treatment capabilities (Table 31-1).^20,23

TABLE 31-1 Antimicrobials Used in Sea Turtle Patients

* Sea turtle pharmacokinetics.

^† Other reptiles.

Most sea turtles presented for emergency care are dehydrated. Hypoglycemia or hyperglycemia is common, so blood glucose determination is essential for choosing the appropriate fluid therapy. Most crystalloid fluids may be used in sea turtles²³; however, overhydration is of particular concern in hypoproteinemic patients. Colloidal fluids may be more appropriate in these cases. Whole-blood transfusions using acid citrate dextrose are indicated in cases of acute hemorrhage and life-threatening anemia (5% or less). Fluid therapy, vitamin K, antibiotics, iron supplementation, and other supportive measures are often successful in less severe cases. A purified bovine hemoglobin (Oxyglobin, Dechra Veterinary Products, Overland Park, Kan) has had limited clinical use in sea turtles, with mixed results. Procrit (Epoetin AFA, Centocur Ortho Biotech, Horsham, Pa) has been used in conjunction with iron and nutritional support and has been helpful in treating non-regenerative anemias. Intravenous (IV) or intraosseous (IO) routes of fluid administration allow for rapid rehydration. Ultrasound is helpful for placing IV catheters. Bolus IV fluid therapy via the cervical sinus is often used for initial stabilization. The intracoelomic (IC) route via the inguinal fossa is commonly used for maintenance fluid therapy and allows for crystalloid fluids with up to 5% dextrose to be given. Subcutaneous fluids are placed in the inguinal fossa, medially in the front limb fossa and ventral neck fold. The oral route of fluid administration should be reserved for use in patients that are mildly dehydrated and maintenance fluid therapy. Placing the turtle in fresh water for 24 hours may be used for rehydration and reduction of epibiotic load. Maintenance fluid rates range from 10 to 25 mL/kg/day.