INHALATION ANESTHESIA WITH ISOFLURANE IN A BLACK JAGUAR (PANTHERA ONCA) FOR SURGICAL REPAIR OF A FRACTURED MANDIBLE

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1 138 Case re port Vlaams Dier ge nees kun dig Tijd schrift, 2007, 76, INHALATION ANESTHESIA WITH ISOFLURANE IN A BLACK JAGUAR (PANTHERA ONCA) FOR SURGICAL REPAIR OF A FRACTURED MANDIBLE Inha la tie anest he sie met isof lu raan bij een zwar te jagu ar (Pan the ra onca) voor de chi rur gi sche cor rec tie van een man di bu laf rac tuur T. Wael bers 1, T. Bos mans 1, M. Ris se la da 2, P. Ver ley en 2, I. Po lis 1 1 De part ment of Small Ani mal Me di ci ne and Cli ni cal Bi o lo gy 2 De part ment of Me di cal Ima ging of Do mes tic Ani mals, Fa cul ty of Ve te ri na ry Me di ci ne Ghent Uni ver si ty, Sa lis bu ry laan 133, B-9820 Me rel be ke tim wael bers@hot mail.com ABSTRACT A black ja gu ar (Panthera onca) was anesthetized with a combination of medetomidine, ketamine and isoflurane in oxygen for radiological examination and surgical repair of a fractured mandible. Since a non-domesticated cat is potentially dangerous, induction of anesthesia was performed by intramuscular injection using a mechanical squeeze cage. The cardiopulmonary parameters during anesthesia remained within normal ranges; only a small increase in the respiration rate was recorded 75 minutes after intubation. This hyperventilation was treated with buprenorphine (for additional analgesia) and an increased inspiratory fraction of isoflurane. Recovery was rather slow after 165 minutes of general anesthesia, so atipamezole was administered. Ten minutes after the intramus - cular injection of atipamezole, the animal started to recover. Meloxicam and buprenorphine were used for post-operative analgesia. SAMENVATTING Een zwar te jagu ar (Panthera onca) werd onder algemene anesthesie gebracht met een combinatie van medetomidine, ketamine en isofluraan met zuurstof voor de radiografische diagnose en chirurgische correctie van een mandibulafractuur. Aang ezien zo n niet-ge do mes ti ceerd dier ge vaar lijk kan zijn, werd het dier in een dwang kooi ge ïnduceerd door middel van een intramusculaire injectie. Tijdens de anesthesie bleven de cardiopulmonaire parameters binnen de normale grenzen; er werd enkel een lichte stijging van de ademhalingsfrequentie geregistreerd 75 minuten na de intubatie. Deze lichte hyperventilatie werd behandeld door de inspiratoire fractie van isofluraan te verhogen alsook door buprenorphine als supplementair analgeticum toe te dienen. De recovery, na 165 minuten algemene verdoving, verliep eerder traag, totdat atipamezole werd toegediend. Tien minuten na de intramusculaire toediening van atipamezole, begon het dier te ontwaken. Meloxicam en buprenorphine werden gebruikt voor de behandeling van de postoperatieve analgesie. INTRODUCTION Jaguars (Panthera onca) are the lar gest fe lid spe cies in the New World and the only mem ber of the ge nus Pan - thera that oc curs in the Ame ri cas (Deem, 2004). They are ex clu si ve fo rest dwel lers and they use their an te ri or limbs to make pri ma ry con tact with their prey, which can even ex ceed their own body weight (Go ny ea, 1976). Most of the veterinary procedures on these species invol ve che mi cal res traint. Be cau se of the ef fects that res - traint stress may have on the physiological parameters, potentially compromising the animal once anesthetized, it is im por tant to mi ni mi ze the ef fects of such res traint (No - gu ei ra and Sil va, 1997; Deem, 2004). The ap pli ca ti on of mecha ni cal res traint, such as a mecha ni cal squee ze cage used for administering an injection to the animal, should be kept as short as pos si ble. Many species of non-domesticated cats are potentially dang erous, even when se da ted, and for this re a son, high do ses of drugs are of ten gi ven to en su re sa fe ty for tho se hand ling the ani mals (For syth et al., 1999). Ho we ver, it ap pe ars that big cats re qui re less anest he tic per ki lo gram

2 Vlaams Dier ge nees kun dig Tijd schrift, 2007, to produce surgical anesthesia compared to smaller domes tic cats (Thur mon et al., 1996). The im por tan ce of appropriate dosing in combination with a correct estimati on of the body weight should be emp ha si zed. Many spe cies of non-do mes ti ca ted cats have been im - mobilized with high doses of ketamine alone, but salivation, muscle rigidity and convulsions often occur (Hime, 1974). Since á2-ago nists are po tent cen tral ner vous sy s - tem depressants with sedative, muscle relaxant and some analgesic properties, the combination of an á2-agonist with ke ta mi ne is pre fer red to ne ga te the side ef fects of the latter (Nielsen, 1996). Combinations of xylazine and ketamine; medetomidine and ketamine; xylazine-midazolamketamine or medetomidine-midazolam-ketamine and even propofol and ketamine have been successfully used to anesthetize different species of wild felids (Jalanka and Koe ken, 1990; Epstein et al., 2002; Cur ro et al., 2004). Tiletamine, another dissociative anesthetic, has also been used for im mo bi li zing wild fe lids, though with con - flicting re sults. Gras sman et al. (2004) used a com bi na tion of tiletamine and zolazepam to immobilize wild felids in Thailand and they preferred this combination over the combination of xylazine and ketamine because of the smal ler vo lu me that had to be in jec ted, the fas ter in duc ti on time and the absence of prolonged muscle rigidity. Fahlman et al. (2005) even used the com bi na ti on of me de to - midine, zolazepam and tiletamine for anesthesia of freeranging lions. In li ons and ti gers, ho we ver, a cert ain per cen ta ge are at risk for a potentially life-threatening reaction to the tiletami ne, which can pre sent one or two days af ter an ap pa - rent ly full re co ve ry. Some ti gers have even died, ap pa - rently from continuous seizure activity and hyperthermia (L. Klein, personal communication, 2000). According to Wack (2003), tiletamine and zolazepam can be used safely in many spe cies of Fe li dae, in which it pro du ces smooth and rapid induction, with good muscle relaxation. It should, ho we ver, not be gi ven to ti gers, es pe ci al ly not to the white variant. In the case of tigers, the combination of medetomidine and ketamine IM was chosen, because of the previously mentioned advantages, in addition to the rather small volume, the route of administration, our experience with this combination and the possibility of antagonizing medetomidine in the event of prolonged recovery. As the pro ce du re was sup po sed to take a long time and be cau se of the fact that oral sur ge ry en han ces the risk for as pi ra ti on of blood, it was op ted to in tu ba te the ani mal and main tain anest he sia using isof lu ra ne in oxy gen. After the IV ca the ter was placed, propofol, a fast acting intravenous anesthetic agent, was used as a sa fe ty me a su re to pro vi de sup ple - men tal anest he sia if it should be nee ded. CASE DESCRIPTION His to ry A 15-year-old fe ma le black ja gu ar (Panthera onca) with an es ti ma ted body weight of 40 kg was pre sen ted with a frac tu red mandible. The ani mal had been rai sed by its ow ner, li ved in cap ti vi ty, and was used to being hand - led, since she participated in commercials and movies. After she got stuck in her cage with her col lar, she tried to free her self by bi ting the bars of the cage. This ac ti on re - sul ted in a frac tu re of the mandible. The animal had already been successfully anesthetized for clinical examination the previous day by the referring veterinarian, who used medetomidine 60 µg/kg (Domitor, Pfizer Animal Health, Louvain-la-Neuve, Belgium) and ketamine 2.5 mg/kg (Anesketin, Eurovet, Heusden-Zolder, Belgium) intramuscularly. At that time she was also treated with antibiotics (amoxicillin and clavula nic acid) (Sy nul ox 8.75 mg/kg SQ, Pfi zer Ani mal Health, Louvain-la-Neuve, Belgium) and the non-steroidalanti-inflammatory drug (NSAID), meloxicam (Metacam 5 mg/ml, Boehringer Ingelheim Vetmedica GmbH, Ger - many), both intramuscularly. She needed to be anesthetized for radiological confirmation of the diagnosis and surgery of the fractured man - dible. Pre-anest he tic exa mi na ti on The ani mal was pre sen ted in the cli nic in a small trans - por ta ti on cage (1x1x0,6m). Sin ce it is a wild ani mal, the pre-anesthetic examination was restricted to the visual observation of the patient. Except for some excessive salivation due to the fractured mandible, the animal seemed to be in good phy si cal con di ti on. Although the ani mal had suf fe red an open frac tu re, blee ding out of the mouth was not ob ser ved. She was re la ti ve ly calm and her res pi - ration was costo-abdominal at a normal rate. According to the ow ner, food and wa ter had been withheld for at le - ast 12 hours. Anest he tic tech ni que The ow ner had trai ned the ani mal to en ter a cage for transport without sedation. With a supplemental steel squee ze wall, the ani mal was pus hed firm ly against the bars of the cage, which made in tra mus cu lar in jec ti on for induction of anesthesia possible.

3 140 Vlaams Diergeneeskundig Tijdschrift, 2007, 76 Figure 1. Jaguar in left lateral recumbency after endotracheal intubation in the preparation room. Fi gu re 2. Ja gu ar in the sur gi cal sui te, with the anest he tic mo ni to ring equip ment at tached; in the middle of the ima ge at the top from left to right: the ECG re cor der (Hew lett Packard) and the multi-anesthetic gas analyzer (Capnomac Ultima, Datex Engstrom Instrumentation Corp.), beneath tho se the pul se oxi me ter (Nellcor Pu ri tan Ben nett Inc.) and at the right hand side the cir cle anest he tic machi ne (Spiromat 656, Dräger, Lübeck, Ger ma ny). Figure 3. Preoperative radiography. An oblique fracture in the right man di bu lar body. Anesthesia was induced with a combination of medetomidine 60 µg/kg (Domitor, Pfizer Animal Health, Louvain-la-Neuve, Belgium) and ketamine 2.5 mg/kg (Anesketin, Eurovet, Heusden-Zolder, Belgium) intramus cu lar ly in the hind limb. After 15 mi nu tes the ani mal was ta ken out of the cage. After the larynx was visualized with a laryngoscope (Miller no. 3 bla de) and spray ed with li do cai ne (Xy lo cai ne 2%, Astra Ze ne ca, Brus sels, Bel gi um), the ani mal was in tu - bated using an 11 mm internal diameter silicone endotracheal tube (Cook Veterinary Products, Queensland, Austra lia). Intu ba ti on went very smoothly and the size of the en dot rache al tube see med to be right. The cuff was left de fla ted, sin ce squee zing the re ser voir bag did not re ve al any leakage around it. General anesthesia was maintained with isoflurane (Isoflo, Abbott Laboratories Ltd., Queensborough, Kent, Uni ted King dom) in 1.4 L/min of oxy gen using a cir cle anest he tic sy stem (Spi ro mat 656, Dräger, Lübeck, Ger - many) and a precision out-of-circuit vaporizer (Vapor 19,3, Dräger, Lübeck, Ger ma ny) (Fi gu re 1). A 20 gauge over-the-needle IV catheter (Optiva 2, Medex Medical Ltd. Haslingden, Rossendale, Great Britain) was placed in the cep ha lic vein and lac ta ted Ringer s so lu ti on (Hart - mann, Bax ter, Les sen, Bel gi um) was in fu sed at a rate of 10 ml/kg/h du ring anest he sia. A blood sam ple was ta ken out of the ju gu lar vein for rou ti ne ana ly sis (va lu es sum - marized in Table 1). The radiological examination, which was performed in the surgical theatre, took 45 minutes and revealed an open, obli que frac tu re in the right man di bu lar body, run ning along the cau dal bor der of the ca ni ne tooth (Fi gu re 3). Surgical repair was required and antibiotics were administered at induc ti on: amoxi cil lin 10 mg/kg IV (Cla moxyl, Glaxo - SmithKlein, Genval, Belgium) perioperatively and amoxi - cil lin and cla vu la nic acid 8.75 mg/kg subcutaneously (Synulox, Pfizer Animal Health, Louvain-la-Neuve, Belgi um). After a stand ard asep tic pre pa ra ti on and with the ja - guar in dorsal recumbency (Figure 2), surgery included an open vent ral ap pro ach to ap po se the bone ends. Three en cir - cling cerclage wires and a dorsal interfragmentary wire in a figure-of-eight configuration were used to maintain appositi on of the frac tu re. Seventy-five minutes after intubation, when the respiration rate was increasing, buprenorphine 0.3 mg (Temge sic 0.3 mg/ml, Sche ring-plough, Brus sels, Bel gi um) was given intravenously. Just prior to recovery, meloxicam 7 mg (Me ta cam 5 mg/ml, Boeh ring er Ingel heim Vetmedica GmbH, Germany) was administered intravenously to provide post-operative analgesia. The animal was co ve red with a he a ting pad during surgery.

4 Vlaams Dier ge nees kun dig Tijd schrift, 2007, Table 1. Haematology and biochemistry of the panthera onca. Sample obtained just after the induction of anesthesia. Hae ma to lo gy (units) Mean Standard deviation WBC ( /µl) Seg men ted Neut rop hils ( /µl) Lymp ho cy tes ( /µl) Mo no cy tes ( /µl) Ba sop hils ( /µl) Eo si nop hils ( /µl) RBC (10 6 /µl) He mog lo bi ne (g/dl) He ma to crit (%) Pla te let Count (10 3 /µl) Bi oche mis try (units) BUN (mg/dl) Cre a ti ni ne (mg/dl) To tal pro tein (g/dl) Albu min (g/dl) To tal Bi li ru bin (mg/dl) AST (IU/l) ALT (IU/l) 55 GGT (IU/l) < Glu co se (mg/dl) Mean va lu es and stand ard de vi a ti on (Deem, 2004). Anesthetic monitoring included multi-gas analysis (Capnomac Ultima, Datex, Helsinki, Finland), which determines inspiratory and end tidal anesthetic agent concentration (FiAA % and ETAA %), inspiratory oxygen fraction (FiO2), end ti dal CO2 concentration (ET CO2 %) and res pi ra to ry rate (RR). Gas sam ples were ta ken at the Y- part with a rate of 200 ml/min and were re tur ned to the anesthetic circuit. Tidal volume (TV) was measured using a respirometer (Volumeter, Dräger, Lübeck, Germany), and heart rate (HR) and peripheral hemoglobin saturation (SpO2 %) were mo ni to red with a pul se oxi me ter (N-20PA Portable Pulse Oximeter, Nellcor Puritan Bennett Inc., Ple a san ton, CA, U.S.A.) with the pro be pla ced on the tongue. The electrocardiogram (ECG) (78352A, Hewlett Packard, Brussels, Belgium) was also continuously recorded. Evaluation of the eyelid reflex was difficult becau se of the dra ping of the sur gi cal area and the po si ti on of the ani mal. The patient breathed spontaneously throughout 165 minutes of general anesthesia. The first 60 minutes after intubation the respiration was rather irregular. At seventy-five minutes after intubation, the respiratory rate sudden ly in cre a sed from 16 breaths per mi nu te to 26 breaths per mi nu te at which time bupre norp hi ne 0.3 mg (Tem ge -

5 142 Vlaams Diergeneeskundig Tijdschrift, 2007, 76 Figure 4. Postoperative radiography (ventrodorsal projection). A good apposition and alignement of the fracture caused by the encircling cerclage wires. was rat her small but sta ble be tween 140 ml and a maxi - mum of 200 ml. The end ti dal CO2 (ET CO2 %) va ried du ring the who le anest he sia pe ri od be tween 3% and 4.6% (23.4 and 35.9 mmhg, res pec ti ve ly). The he art rate in cre a - sed from 48 be ats per mi nu te (bpm) in the be gin ning, to 85 bpm at the end of anest he sia. Car di ac arrhythmi as were not ob ser ved. SpO2% re mai ned be tween 97 and 100%. After completion of surgery and postoperative radiographs, the venous catheter and all monitoring devices were re mo ved in case the re co ve ry should be un ex pec - tedly rapid. The radiographs showed good apposition and alignment (Fi gu res 4 and 5). Isof lu ra ne was dis con ti - nu ed, and the ani mal was ex tu ba ted and pla ced in its cage. The rec tal tem pe ra tu re at this time was 35.3 C, despite the use of a heating pad during surgery. Sin ce the ani mal was still not res pon si ve 45 mi nu tes after cessation of isoflurane administration, atipamezole 5 mg (Anti se dan, Pfi zer Ani mal He alth, Lou vainla-neuve, Belgium) was given intramuscularly. Ten minu tes la ter the ani mal star ted to res pond to noi se, so was mo ved into the truck and re tur ned home. The day af ter sur ge ry the ani mal was bright and res pon si ve and was al - re a dy able to eat small pie ces of meat, as ad vi sed. She re - cei ved an ti bi o tics mixed in her food du ring the fol lo wing five days (Sy nul ox 12.5 mg/kg PO b.i.d., Pfi zer Ani - mal Health, Louvain-la-Neuve, Belgium). According to the veterinarian, the animal was in good condition two months after surgery. Normally speaking, the three encircling cerclage wires and the dorsal interfragmentary wire still need to be re mo ved. DISCUSSION Figure 5. Postoperative radiography (lateral projection). sic 0.3 mg/ml, Sche ring-plough, Brus sels, Bel gi um) was administered intravenously and the inspiratory fracti on of isof lu ra ne was aug men ted from 0.8 to 1.2 (FiAA %), which re sul ted in a re turn to 18 breaths per mi nu te at 100 minutes after intubation. The difference between the FiAA% ( %) and the ETAA% ( %) was sta - ble un til the va po ri zer was tur ned hig her; 15 mi nu tes la ter the difference stabilized again at a higher level ( % and %, res pec ti ve ly), and re mai ned at this le vel un til the va po ri zer was swit ched off. The ti dal vo lu me Persons undertaking to immobilize a wild animal take on res pon si bi li ty for the he alth and sa fe ty of the ani mal and of all the per sons wor king with it. Sin ce the se ani - mals are more sus cep ti ble to stress than do mes ti ca ted ani mals, it is im por tant to in du ce anest he sia as quic kly as pos si ble. This is why, in our case, the ani mal was pla ced in quiet surroundings and anesthesia was rapidly induced using a combination of medetomidine and ketamine. Another difference compared to domesticated animals is the necessity to use intramuscular anesthetics in the wild species before placing an intravenous catheter. In general, anesthetic agents are administered by remote drug delivery systems (Deem, 2004), or exceptionally, as in this case, by an in tra mus cu lar in jec ti on through the bars of a squee ze cage, sin ce this ani mal was used to hu man hand ling. As in do mes tic ani mals, adult fe lids should be fa sted for at le ast 24 hours, and wa ter should be withheld

6 Vlaams Dier ge nees kun dig Tijd schrift, 2007, for 12 hours before immobilization, to decrease the incidence of emesis and aspiration during induction and reco ve ry from anest he sia (Le wis, 1994; Wack, 2003). The blood results revealed that the thrombocyte count was clearly below the normal range. Possible explanations in clu de clot ting of the sam ple or the dif fe ring size of the platelets, which renders them undetectable for the blood count apparatus. According to Harvey (2001), platelet aggregates may occur even in properly collected EDTAanticoagulated blood samples, and even small clots render a sam ple unu se a ble, as the pla te let counts are mar ked - ly re du ced. The in cre a se of whi te blood cells cau sed by the elevation of segmented neutrophils, together with the decrease of lymphocytes and eosinophils, can be caused by stress. The high va lue of BUN is pro ba bly due to slight dehydration of the animal. The choi ce of the anest he tic agents used de pends on the type of in ter ven ti on and sur ge ry, and the pre sen ce or ab sen ce of pain. Acu te pain is the re sult of a trau ma tic, sur gi cal, or in fec ti ous event that is ab rupt in on set and re - latively short in duration. In general, it is alleviated by anal ge sic drugs. Drugs that can be used to re du ce acu te pain in clu de the opi oids, lo cal anesthetics, á2 agonists and non-steroidal anti-inflammatory drugs (Dobromylskyi et al., 2000). Ba lan ced anal ge sia re sults from the ad mi ni - stration of analgesic drugs, in combination and at multiple si tes, to in du ce anal ge sia by al te ring more than one portion of the nociceptive process (Thurmon et al., 1996). For all these reasons, a combined analgesic protocol including medetomidine, buprenorphine, ketamine and meloxicam was used. In addition to their strong sedative effects, á2-adrenoreceptor agonists have potent antinociceptive action, as described in both human and veterinary experimental and cli ni cal stu dies (Maze and Tran quil li, 1991; Pert o - vaara, 1993). Although most ly used for pre-anest he tic medication, the antinociceptive action contributes to the intraoperative analgesia (Ossipov et al., 1990). Additional advantages of incorporating an α2-ago nist into the anes - thetic protocol include both its reversibility and the resulting re duc ti on of the amount of ot her anest he tics re qui red for surgery. (Murrell and Hellebrekers, 2005). Medetomi di ne is a very se lec ti ve and po tent α2-ago nist with a profound sedative and analgesic activity (Thurmon et al., 1996). Following subcutaneous or intramuscular administration of medetomidine, bradycardia, peripheral vasoconstriction, vomiting and production of large volumes of di lu te uri ne may be ob ser ved (Thur mon et al., 1996). In our case ho we ver, vo mi ting did not oc cur, the production of urine was not monitored and the vasoconstriction was insufficient to cause difficulties in placing an IV catheter. The bradycardic effects of medetomidine were probably offset by the sympathomimetic properties of ketamine. The antinociceptive synergism between á2 agonists and opioids is recognized (Ossipov et al., 1990). Therefore, buprenorphine, a partial ì-opioid agonist-antagonist, was ad ded to the anal ge sic pro to col. Its on set of action is relatively slow, requiring 20 to 30 minutes to reach full ef fect, but the anal ge sic ac ti on may last as long as 8 to 12 hours (Thur mon et al., 1996). In the pre sent case, buprenorphine was administered intravenously 75 minutes after intubation and when the respiration rate was increasing, pro ba bly as a re ac ti on to a pain ful sti mu lus du ring surgery. Non-steroidal anti-inflammatory drugs (NSAIDs) inhi bit the for ma ti on of pros tag lan dins, which have a pri - ma ry role in in flam ma ti on but are also cri ti cal to many physiological responses (Carroll and Simonson, 2005). NSAIDs ge ne ral ly are not suf fi cient by them sel ves to re - lie ve se ve re post ope ra ti ve pain, but they can be used in combination with opioids postoperatively to good effect be cau se the two dif fe rent drug groups have dif fe rent si tes and mecha nisms of ac ti on (Thur mon et al., 1996). Mel o - xicam is a NSAID with po tent anti-in flam ma to ry and analgesic properties and low gastrointestinal and renal toxicity (Carroll and Simonson, 2005). Because of the risk of transient hypotension or hemorrhage occurring during general anesthesia, meloxicam was administered just prior to recovery. If given preoperatively, fluids should be administered to support circulating volume (Carroll and Simonson, 2005). The administration of fluids to maintain normal blood pressure during anesthesia also decreases reco ve ry time (Wack, 2003). In our case, lac ta ted Ringer s so - lution (Hartmann, Baxter, Lessen, Belgium) was infused at a rate of 10 ml/kg/h du ring anest he sia. Ke ta mi ne, on the ot her hand, which was used for in duc - tion of anesthesia, is a non-competitive antagonist to the phencyclidine site of the N-methyl-d-aspartate (NMDA) receptor for glutamate. The effects, however, are mediated by interactions with many other receptors (Annetta et al., 2005). Ketamine produces dose-related unconsciousness and anal ge sia (Lin, 1996). It has been used suc ces sful ly in many spe cies, and do ses vary wi de ly from one spe cies to anot her (Niel sen, 1996). The side ef fects of ke ta mi ne immobilization may include convulsions, catatonia, apnea, excessive salivation and hyperthermia as a consequence of ca ta to nia (Niel sen, 1996). The use of ke ta mi ne is also known to cau se an ap neus tic, shal low and ir re gu lar breat h - ing pat tern (Lin, 1996). Many of the se side ef fects can be counteracted by adding a benzodiazepine or an α2-ago - nist, as was done in our case (Thur mon et al., 1996).

7 144 Vlaams Diergeneeskundig Tijdschrift, 2007, 76 When a procedure is expected to be of considerable duration, inhalation anesthesia and endotracheal intubation is preferred. Before endotracheal intubation, which can be achie ved blind ly or with a la ryng os co pe, the la - rynx should be spray ed with a lo cal anest he tic to de cre a se the likelihood of laryngeal spasms (Thurmon et al., 1996). Tu bes of in ter nal di a me ters be tween 12 and 18 mm are generally suitable for adult medium-sized cats (Lewis, 1994). In our case, the ani mal was in tu ba ted using an 11 mm id si li co ne en dot rache al tube. The cuff was left de fla - ted, sin ce squee zing the re ser voir bag did not re ve al any leakage. Isoflurane, sevoflurane or halothane can be used safely as inhalation anesthetics in wild felids using precision vaporizers. According to Lewis (1994), isoflurane is the in ha lant anest he tic agent of choi ce in non-do mes tic cats. In spi te of the fact that re co ve ry time might have been a little shorter using sevoflurane, isoflurane was used, main ly be cau se of the ex pe rien ce of the aut hors using this in ha lant. A ventilator can be helpful for maintaining respiration because subclinical hypoxia is a common finding (Wack, 2003). In our case, des pi te the fair ly small ti dal vo lu me, SpO2% re mai ned abo ve 97% and ET CO2% did not ex - ceed 35.9 mmhg, so the pa tient was not ventilated. Recovery is another critical point in the management of anest he sia in lar ge exo tic fe li ne spe cies. Due to sa fe ty considerations, intervention is usually impossible during this time. The re fo re, the pa tient and the re co ve ry area must be carefully prepared and recovery should be as fast as possible (Epstein et al., 2002). Since the recovery of the animal was relatively slow, atipamezole was administered intramuscularly, 45 minutes after cessation of isoflurane administration. Atipamezole is an á2-adrenoceptor antagonist with a high affinity for á2-adrenoceptors (high á2/ á1 selectivity ratio). It rapidly reverses sedation and anesthesia induced by á2-adrenoceptor agonists like medetomidine (Pertovaara, 2005). In a stu - dy involving 5 lions, atipamezole was able to reverse medetomidine-ketamine induced anesthesia smoothly and rapidly (Tomizawa et al., 1997). In anot her stu dy in vol - ving 6 adult lions anaesthetized with xylazine-ketamine, seizures occurred in 2 lions after xylazine was antagonized at the end of the pro ce du re (Epstein, 2002). The time be - tween induction of anesthesia and injection of atipamezo le was much long er in the first stu dy (± 60 mi nu tes) than in the se cond (± 15 mi nu tes), which might ex plain the seizures. As atipamezole also reverses the analgesic effect of á2-adrenoceptor agonists, the need for additional analgesic medication must be evaluated, especially when painful procedures have been performed (Granholm et al., 2006). In our case anal ge sia was pro vi ded by bupre nor - phine and meloxicam as described previously. Ten minutes after the administration of the atipamezole, the animal star ted to re act to noi se, so it was then mo ved into the truck and returned home. Complete recovery was reached at home. CONCLUSION Inhalation anesthesia with isoflurane in oxygen after induction of anesthesia using medetomidine and ketamine IM in a jaguar resulted in stable cardiopulmonary values throughout anesthesia. Adequate postoperative analgesia was provided using buprenorphine and meloxicam. Recovery was smooth and uneventful after atipamezole was used to antagonize the medetomidine. 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