Anesthesia, Analgesia and Pain

Barter, L.S., M.G. Hawkins, R.J. Brosnan, J.F. Antognini, and B.H. Pypendop (2006). Median effective dose of isoflurane, sevoflurane, and desflurane in green iguanas. American Journal of Veterinary Research 67(3): 392-397. ISSN: 0002-9645.
NAL Call Number: 41.8 Am3A
Descriptors: reptiles, Iguana iguana, anesthesia, isoflurane, dose response, breathing, drug delivery systems, cardiovascular system, duration, adverse effects, pharmacokinetics, sevoflurane, desflurane.

Brosnan, R.J., B.H. Pypendop, L.S. Barter, and M.G. Hawkins (2006). Pharmacokinetics of inhaled anesthetics in green iguanas (Iguana iguana). American Journal of Veterinary Research 67(10): 1670-1674. ISSN: 0002-9645.
NAL Call Number: 41.8 Am3A
Descriptors: reptiles, green iguanas, Iguana iguana, inhaled anesthetics, pharmacokinetics.

Chittick, E.J., M.A. Stamper, J.F. Beasley, G.A. Lewbart, and W.A. Horne (2002). Medetomidine, ketamine, and sevoflurane for anesthesia of injured loggerhead sea turtles: 13 cases (1996-2000). Journal of the American Veterinary Medical Association 221(7): 1019-1025. ISSN: 0003-1488.
NAL Call Number: 41.8 Am3
Abstract: OBJECTIVE: To determine safety and efficacy of an anesthetic protocol incorporating medetomidine, ketamine, and sevoflurane for anesthesia of injured loggerhead sea turtles. DESIGN: Retrospective study. ANIMALS: 13 loggerhead sea turtles. PROCEDURE: Anesthesia was induced with medetomidine (50 microg/kg [22.7 microg/lb], IV) and ketamine (5 mg/kg (2.3 mg/lb], IV) and maintained with sevoflurane (0.5 to 2.5%) in oxygen. Sevoflurane was delivered with a pressure-limited intermittent-flow ventilator. Heart rate and rhythm, end-tidal partial pressure of CO2, and cloacal temperature were monitored continuously; venous blood gas analyses were performed intermittently. Administration of sevoflurane was discontinued 30 to 60 minutes prior to the end of the surgical procedure. Atipamezole (0.25 mg/kg [0.11 mg/lb], IV) was administered at the end of surgery. RESULTS: Median induction time was 11 minutes (range, 2 to 40 minutes; n = 11). Median delivered sevoflurane concentrations 15, 30, 60, and 120 minutes after intubation were 2.5 (n = 12), 1.5 (12), 1.25 (12), and 0.5% (8), respectively. Heart rate decreased during surgery to a median value of 15 beats/min (n = 11). End-tidal partial pressure of CO2 ranged from 2 to 16 mm Hg (n = 8); median blood gas values were within reference limits. Median time from atipamezole administration to extubation was 14 minutes (range, 2 to 84 minutes; n = 7). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that a combination of medetomidine and ketamine for induction and sevoflurane for maintenance provides safe, effective, controllable anesthesia in injured loggerhead sea turtles.
Descriptors: reptiles, loggerhead sea turtles, anesthesia, medetomidine, ketamine, sevoflurane, drug combination, induction, maintenance.

Edling, T.M. (2003). Advances in anesthesia monitoring in birds, reptiles and small mammals. Exotic DVM 5(3): 15-20. ISSN: 1521-1363.
NAL Call Number: SF981.E96
Descriptors: reptiles, anesthesia, advances, monitoring, birds, small mammals, meeting.
Notes: Meeing Information: International Conference on Exotics (ICE2003), Palm Beach, Florida, USA, 2003.

Hawkins, M.G. (2006). The use of analgesics in birds, reptiles, and small exotic mammals. Journal of Exotic Pet Medicine 15(3): 177-192. ISSN: 1557-5063.
NAL Call Number: SF994.2.A1 S36
Descriptors: reptiles, birds, small exotic mammals, analgesic use, veterinarians, pain, alleviation.

Hernandez Divers, S.J., H. Wilson, M. McBride, and K. Grant (2003). Sedation/restraint of small lizards and snakes. Exotic DVM 5(5): 9. ISSN: 1521-1363.
NAL Call Number: SF981.E96
Descriptors: reptiles, snakes, small lizards, sedation, restraint, anesthesia, anesthetics, analgesia, techniques.

Hernandez Divers, S.M., J. Schumacher, S. Stahl, and S.J. Hernandez Divers (2005). Comparison of isoflurane and sevoflurane anesthesia after premedication with butorphanol in the green iguana (Iguana iguana). Journal of Zoo and Wildlife Medicine 36(2): 169-175. ISSN: 1042-7260.
NAL Call Number: SF601.J6
Descriptors: reptiles, green iguana, Iguana iguana, anesthesia, sedation, isoflurane, sevoflurane, butorphanol, premedication, comparison, evaluation.

Hernandez Divers, S.M., J. Schumacher, S. Stahl, and S.J. Hernandez Divers (2004). Reptile clinical anesthesia: advances in research. Exotic DVM 6(3): 64-69. ISSN: 1521-1363.
NAL Call Number: SF981.E96
Descriptors: reptiles, clinical anesthesia, analgesia, sedation, advances, research.

Longley, L. (2004). Practitioner's guide to reptile anaesthesia. Veterinary Times 34(31): 22-23. ISSN: 1352-9374.
Descriptors: reptiles, anesthesia, analgesia, dosage and administration.

Longley, L. (2004). Reptile analgesia. Veterinary Times 34(25): 30. ISSN: 1352-9374.
Descriptors: reptiles, anesthetics, analgesics, antagonists, ketamine, non steroidal anti-inflammatory agents, opioids, pain, pharmacodynamics.

Mauthe von Degerfeld, M. (2004). Personal experiences in the use of association tiletamine/zolazepam for anaesthesia of the green iguana (Iguana iguana). Veterinary Research Communications 28(1): 351-353 (Suppl). ISSN: 0165-7380.
Descriptors: reptiles, green iguana, Iguana iguana, sedation, anesthesia, analgesia, tiletamine, zolazepam.

Mosley, C.A., D. Dyson, and D.A. Smith (2004). The cardiovascular dose-response effects of isoflurane alone and combined with butorphanol in the green iguana (Iguana iguana). Veterinary Anaesthesia and Analgesia 31(1): 64-72. ISSN: print: 1467-2987; online: 1467-2995.
NAL Call Number: SF914.V47
Abstract: OBJECTIVE: To assess the cardiovascular effects (arterial blood pressure, heart rate, and metabolic acid-base status) of three doses (MAC multiples) of isoflurane alone and combined with butorphanol in the green iguana (Iguana iguana). STUDY DESIGN: Prospective randomized double-blind, two-period cross-over trial. ANIMALS: Six mature healthy green iguanas (Iguana iguana). METHODS: The iguanas received each of two treatments, saline 0.1 mL kg(-1) (SAL) and butorphanol 1.0 mg kg(-1) (BUT) during isoflurane anesthesia. Treatments were separated by at least 1 week. The iguanas were exposed to each of the three minimum alveolar concentration (MAC) multiples (1.0, 1.5, and 2.0) in random order. Anesthesia was induced with isoflurane and maintained using controlled ventilation. Instrumentation included use of an ECG, airway gas monitor, cloacal thermometer, esophageal pulse oximeter, and the placement of a femoral arterial catheter. Body temperature was stabilized and maintained at 32 degrees C. The treatment was administered, and the animals were equilibrated for 20 minutes at each MAC multiple. At each concentration, the heart rate, blood pressure (systolic, mean, diastolic), end-tidal CO2, and SpO2 were measured. At 1.0 and 2.0 MAC, simultaneous blood samples were drawn from the tail vein/artery complex and femoral catheter for blood gas analysis. Data were analyzed using a two-way analysis of variance for repeated measures looking for differences between treatments and among MAC multiples. RESULTS: There were no significant differences in any of the cardiovascular variables between the treatments. Significant differences among isoflurane MAC multiples were observed for HR, mean, diastolic, and systolic blood pressures. Blood pressure and heart rate decreased with an increasing dose of anesthetic. There were no significant differences between treatments or MAC multiples for any of the blood gas variables. The blood pH, PCO2, HCO3-, and hemoglobin saturation differed significantly between sites. Pulse oximetry values measured from the carotid complex did not correlate with and were significantly different from the calculated hemoglobin saturation values determined using the gas analyzer. CONCLUSION AND CLINICAL RELEVANCE: Cardiovascular depression associated with isoflurane anesthesia in the green iguana is dose dependent. The degree of cardiovascular depression was not significantly different when isoflurane was combined with butorphanol. This finding suggests that the pre-emptive or intraoperative use of butorphanol is unlikely to be detrimental to cardiovascular function. Butorphanol may be a useful anesthetic adjunct to isoflurane anesthesia in the green iguana.
Descriptors: green iguana, Iguana iguana, iguanas, analgesics, inhalation anesthetics, blood pressure, drug effects, butorphanol, heart rate, isoflurane.

Mosley, C.A.E., D. Dyson, and D.A. Smith (2003). The cardiac anesthetic index of isoflurane in green iguanas. Journal of the American Veterinary Medical Association 222(11): 1565-1568. ISSN: 0003-1488.
NAL Call Number: 41.8 Am3
Descriptors: reptiles, green iguanas, isoflurane, cardiac anesthetic index, butorphanol, induction of anesthesia, cardiovascular arrest.

Mosley, C.A.E., D. Dyson, and D.A. Smith (2003). Minimum alveolar concentration of isoflurane in green iguanas and the effect of butorphanol on minimum alveolar concentration. Journal of the American Veterinary Medical Association 222(11): 1559-1564. ISSN: 0003-1488.
NAL Call Number: 41.8 Am3
Descriptors: reptiles, green iguanas, isoflurane, minimum alveolar concentration, butorphanol, effect on mimimum alveolar concentration.

Mosley, C.A.E. (2005). Anesthesia and analgesia in reptiles. Seminars in Avian and Exotic Pet Medicine 14(4): 243-262. ISSN: 1055-937X.
NAL Call Number: SF994.2.A1S36
Descriptors: reptiles, anesthesia, analgesia, sedation, review.

Nagaraja, B.N., S.M. Usturge, S.D. Sonwane, and M.G. Manjunath (2003). Ketamine hydrochloride for fish hook retrieval in a turtle under field conditions. Indian Veterinary Journal 80(5): 443-444. ISSN: 0019-6479.
NAL Call Number: 41.8 IN2
Descriptors: reptiles, turtle, fish hook retrieval, ketamine hyrochloride, field conditions.

Nevarez, J.G., G.R. Pettifer, and M.A. Mitchell (2002). Anesthesia case of the month. A suitable choice for anesthetic management of a green iguana for an orchidectomy. Journal of the American Veterinary Medical Association 220(7): 982-985. ISSN: 0003-1488.
NAL Call Number: 41.8 Am3
Descriptors: reptiles, green iguana, anesthesia, orchidectomy, anesthetic management, case of the month.

Park, I.S., S.H. Cho, J.W. Hur, G.C. Choi, S.Y. Oh, D.S. Kim, and J.S. Lee (2006). Lidocaine hydrochloride-sodium bicarbonate as an anesthetic for soft-shelled turtle Pelodiscus sinensis. Fisheries Science Tokyo 72(1): 115-118. ISSN: 0919-9268.
Descriptors: reptiles, soft shelled turtle, Pelodiscus sinensis, sedation, anesthetic, lidocaine hydrochloride, sodium bicarbonate, effect.

Read, M.R. (2004). Evaluation of the use of anesthesia and analgesia in reptiles. Journal of the American Veterinary Medical Association 224(4): 547-552. ISSN: 0003-1488.
NAL Call Number: 41.8 Am3
Abstract: OBJECTIVE: To determine anesthetic techniques and the drugs used to provide anesthesia and analgesia to reptiles. DESIGN: Mail-out questionnaire. SAMPLE POPULATION: 367 members of the Association of Reptile and Amphibian Veterinarians. PROCEDURE: 1,091 members listed in the 2002 directory of the Association of Reptile and Amphibian Veterinarians were asked to complete a questionnaire regarding anesthesia and analgesia. RESULTS: 367 of 1,091 (33.6%) individuals completed the questionnaire; 88.8% used inhalants (particularly isoflurane) for anesthesia, and ketamine, propofol, and butorphanol were the most commonly used injectable agents. Intubation, fluids, and having a dedicated anesthetist were most commonly used for patient support, and pulse oximetry and Doppler ultrasonography were most commonly used for monitoring. Respiratory depression, difficulty monitoring anesthetic depth, prolonged recovery, and hypothermia were the most frequent complications. Nearly all respondents believed that reptiles feel pain, but analgesics were used infrequently for many reasons. CONCLUSIONS AND CLINICAL RELEVANCE: Providing anesthesia in reptiles is difficult, especially regarding anesthetic depth and vital parameters, and methods of support are used less frequently than in domestic species. Provision of analgesia is uncommon. Research regarding pain and its assessment, response to analgesics, and drug pharmacokinetics is needed. Dissemination of this information to practitioners needs to be improved for enhancement of the standard of care for reptiles.
Descriptors: reptiles, anesthesia, analgesia, evaluation of use, drugs, techniques, questionnaire, isoflurans, ketamine, propofol, butorphanol, inhalants, injectable, respiratory depression, hypothermia, prolonged recovery, depth of anesthesia.
Notes: Comment In: J Am Vet Med Assoc. 2004 Apr 15;224(8):1245; author reply 1245.

Rosenthal, K. (2004). Reptile pain management - is there such a thing? In: Small Animal and Exotics Book two: Pain Management - Zoonosis. Proceedings of the North American Veterinary Conference, Volume 18,January 17, 2004-January 21, 2004, Orlando, Florida, Eastern States Veterinary Association: Gainesville, FL, p. 1342.
NAL Call Number: SF605.N672
Descriptors: reptiles, pain management, anesthesia, analgesia, drugs.

Schumacher, J. (2002). Sevoflurane in reptiles. Proceedings of the North American Veterinary Conference 16(16): 950. ISSN: 0003-1488.
NAL Call Number: SF605.N672
Descriptors: reptiles, inhaled anesthetics, sevoflurane, meeting, veterinary.
Notes: In the volume: Small Animal and Exotics. Part of a three volume set. Meeting held January 12-16, 2002, Orlando, Florida. Includes references.

Schumacher, J. (2002). Anesthesia of reptiles. Proceedings of the North American Veterinary Conference 16(16): 946-947. ISSN: 0003-1488.
NAL Call Number: SF605.N672
Descriptors: reptiles, anesthesia, analgesia, pain, monitoring, meeting.
Notes: In the volume: Small Animal and Exotics. Part of a three volume set. Meeting held January 12-16, 2002, Orlando, Florida. Includes references.

Sladky, K.K., V. Miletic, J. Paul Murphy, M.E. Kinney, R.K. Dallwig, and S.M. Johnson (2007). Analgesic efficacy and respiratory effects of butorphanol and morphine in turtles. Journal of the American Veterinary Medical Association 230(9): 1356-1362. ISSN: 0003-1488.
NAL Call Number: 41.8 Am3
Abstract: OBJECTIVE: To test the hypothesis that butorphanol or morphine induces antinociception with minimal respiratory depression in conscious red-eared slider turtles. DESIGN: Prospective crossover study. ANIMALS: 37 adult male and female red-eared slider turtles (Trachemys scripta). PROCEDURES: Antinociception (n = 27 turtles) and respiratory (10 turtles) experiments were performed. Infrared heat stimuli were applied to the plantar surface of turtle limbs. Thermal withdrawal latencies were measured before and at intervals after SC administration of physiologic saline (0.9% NaCl) solution, butorphanol tartrate (2.8 or 28 mg/kg [1.27 or 12.7 mg/lb]), or morphine sulfate (1.5 or 6.5 mg/kg [0.68 or 2.95 mg/lb]). Ventilation was assessed in freely swimming turtles before and after SC administration of saline solution, butorphanol (28 mg/kg), or morphine (1.5 mg/kg). RESULTS: For as long as 24 hours after injection of saline solution or either dose of butorphanol, thermal withdrawal latencies among turtles did not differ. Low- and high-dose morphine injections increased latencies significantly by 8 hours. Ventilation was not altered by saline solution administration, was temporarily depressed by 56% to 60% for 1 to 2 hours by butorphanol (28 mg/kg) administration, and was significantly depressed by a maximum of 83 +/- 9% at 3 hours after morphine (1.5 mg/kg) injection. Butorphanol and morphine depressed ventilation by decreasing breathing frequency. CONCLUSIONS AND CLINICAL RELEVANCE: Although widely used in reptile species, butorphanol may not provide adequate antinociception for invasive procedures and caused short-term respiratory depression in red-eared slider turtles. In contrast, morphine apparently provided antinociception but caused long-lasting respiratory depression.
Descriptors: reptiles, turtles, analgesic efficacy, respiratory effects, butorphanol, morphine, antinociception, respiratory depression.