Animal Research International (201 7 ) 1 4 ( 1 ): 2562 – 2567 2562 EVALUATION OF THE USE OF PENTAZOCINE IN COMBINATION WITH DIAZEPAM AND KETAMINE FOR SURGICAL ANAESTHESIA IN RABBITS UDEGBUNAM, Rita Ijeoma, UDEGBUNAM, Sunday Ositadimma, ONUBA, Austine Chukwudum, UGWU, Nnenna Ebere Department of Veterinary Surgery, Facult y of Veterinary Medicine, University of Nigeri a, Nsukka, Enugu State , Nigeria . Corresponding Author : Ugwu, N. E. Department of Veterinary Surgery, University of Nigeria, Nsukka, Enugu State , Nigeria. Email: nne [email protected] Phone: +234 8136210721 ABSTRACT The effect of pentazocine on diazepam/ketamine anaesthesia was evaluated in this study. Pentazocine (10 mg/kg) was administered intramuscularly ( im ) pri or to injection of diazepam (2 mg/kg , iv ) and ke tamine (15 mg/kg , im ) in pentazocine /diazepam/ketamine (P/D/K) group. In the diazepam/ketamine group, anaesthesia was induced using diazepam ( 2 mg/kg , iv) and ketamine (15 mg/kg, im ). All rabbits were laparotomized after induction of anaesthesia. Intra op eratively, anaesthetic indices, physiologic variables and pain responses of rabbits were studied. Blood glucose and serum cortisol of rabbits were monitored post laparotomy. The durations of analgesia and anaesthesia were significantly shorter ( p <0.05) in the P/D/K group. Respiratory rates of P/D/K group were significantly higher (p<0.05) than those of D/K group. Pain scores of P/D/K group were significantly higher (p<0.05) than scores obtained in D/K group. At 30 and 90 minutes post laparotomy, blood gluco se and serum cortisol of P/D/K group were significantly higher ( p <0.05) than those of D/K group. This study showed that pentazocine/diazepam/ketamine drug combination did not produce surgical anaesthesia in rabbits. Keywords: Ketamine , Diazepam , Pentazoci ne , Combined therapy, Surgical a naesthesia , Rabbit INTRODUCTION general anaesthesia which allows painless surgery is attained. General anaesthesia is a drug induced state of Ketamine is a dissociative anaesthetic unconsciousness characterized by controlled but notably used for its deep somatic analgesic reversible depression of the central nervous effect and wide margin of safety (Henke et al ., system and analgesia (Thurmon and Short, 2005; Orr et al ., 2005; Grint and Muriso n, 2007). Most often, single anaesthetic agents 2008). Ketamine however is rarely used alone when used for general anesthesia are unable to since it produces a cataleptoid state produce surgical anaesthesia. Thus in modern characterized by poor muscle relaxation, muscle veterinary practice, the technique of balanced tremors, myotonic contractions, opistotonus and anaesthesia is often employed. This anaesthetic rough recovery (Green et al ., 1981; Christensen technique requires concomitant administration et al ., 1987; Mohammad et al ., 1993). Thus to of multiple drugs to produce individual counteract these undesirable effects, various components of the anaesthetic state namely drugs such as xylazine, medetomidine, unconsciousness, analgesia, muscle relaxation diazepam and acepromazine have been used in and alteration of autonomic reflexes (Thurmon combin ation with ketamine ( Nuh, 2004 ; Amarpal and Short, 2007). Ultimately, following this et al. , 2010). The agent most widely used in practice, surgical an aesthesia, a plane of combination with ketamine is xylazine an alpha - 2 agonist (Lipman et al ., 2008). ISSN: 1597 – 3115 ARI 201 7 1 4( 1 ): 2562 – 2567 www.zoo - unn.org Udegbunam et al. 2563 Ketamine/xylazine combination has been acclimatize for 14 days. During the period of reported to produce surgical anaesthesia in study, they were fed with commercial breeders’ rabbit but with some mortality (White and diet supplemented with potatoes’ leaves and Holme, 1976). Other ketamine based water was provided ad libitum . After combinations described for anaest hetizing acclimatization , the rabbits were randomly rabbits include ketamine/medetomidine (Orr et assigned to two treatment groups of five al ., 2005; Grint and Murison, 2005; Amarpal et rabbits, each rabbit represented a replicate. The al ., 2010), ketamine/acepromazine ( Amarpal et groups were the diazepam/ketamine ( D/K) and al., 2010; Oguntoye and Oke, 2014) and pentazocine /diazepam/ ketamine ( P/D/K ) groups ketamine/xylazine (Henke et al ., 2005; Amarpal respectively. This research was approved by the et al ., 2010; Oguntoye and Oke, 2014). Animal Ethics Committee, University of Nigeria, Diazepam/ketamine combination produces short Nsukk a. duration anaesthesia, fair muscle relaxation and minimal cardiopulmonary depression in goats Pre - anaesthetic protocols : Baseline readings (Ghurashi et al ., 2009). Although this of heart rates (HR) and respiratory rates (RR) of combination appears ideal for rabbit rabbits were obtained at 0 minute before anaesthesia, it produces inadequate surgical anaesthetic induction. Blood samples were analgesia (R edah, 2011; Oguntoye and Oke, collected from jugular veins of rabbits and 2014 ) . Therefore, to attain a plane of surgical dispensed into tubes containin g ethylene anaesthesia there may be need for the diamine tetra acetate (EDTA) and into test tubes administration of potent analgesics pre without anticoagulant. Blood glucose values operatively prior to use of diazepam/ketamine were determined by the glucose oxidase method for anaesthesia. using a commercial glucose kit (Accu - chek Pent azocine is an agonist - antagonist Advantage II, Roche diagnostic, Germany). opioid and exerts mild analgesic action by acting Serum separated from c lotted blood samples on the kappa opioid receptor (Lamont and were collected within 30 minutes and used for Mathews, 2007; Lipman et al., 2008). Previous serum cortisol determination using a commercial studies carried out using rabbits showed that enzyme linked immunosorbent assay kit. use of butorphanol (an agonist - antagonis t opioid) in combination with xylazine/ketamine Induction of anaesthesia : In P/D/K group, improved operating conditions in rabbits (Marini 10 mg/kg pentazocine (Pentalab, Laborate et al., 1992). Despite the aforementioned Pharmaceutical, I ndia) was injected benefit of concurrent use of this opioid for intramuscularly 30 minutes bef ore intravenous general anaesthesia, nothing is known of the injection of 2 mg/kg diazepam (Valium, Roche, effect of pentazocine on th e quality of France). After a 5 minutes latency period, 15 anaesthesia produced by diazepam/ketamine mg/kg ketamine (Ketamine, Rotex Medica, drug combination. This study evaluated the Germany) was injected intramuscularly to effect of prior use of pentazocine on induce anaesthesia . Rabbits in diazepam diazepam/ketamine anaesthesia. To ascertain /ketamine (D /K) group were injected with 2 this, the anaesthetic and analgesic effects of mg/kg diazepam intravenously five minutes pentazocine/diazepam/ketamine combination prior to intramuscular injection of 15 mg/kg were compared with those of ketamine. diazepam/ketamine combination. Laparotomy : After induction of anaesthesia, MATERIALS AND METHODS rabbits were placed on insulated operating table s and their midventral abdomen shaved Animals : Twenty 10 months old male New and prepared for aseptic surgery. A paramedian Zealand white rabbits weighing between 1.2 – laparotomy incision was made 2 cm caudal to 1.8 kg were used in this study. They were the xiphoid region down to 1 cm below the housed in standard cages and were left to umbilicus through the subcutaneous tissues, Animal Research International (201 7 ) 1 4 ( 1 ): 2562 – 2567 Pentazocine in combination with diazepam and ketamine for surgical anaesthesia 2564 muscle and peritoneum and into the abdome n. Data Analysis : The mean parametric data Thereafter, the peritoneum, muscles and obtained in the P/D/K group were c ompared subcutaneous tissues were sutured with simple respectively with those of D/K group using T - continuous pattern using size 2/0 chromic test. Pain scores were compared using Kruskall - catgut suture. The skin was sutured with size Wallis test. Probability values less than 0.05 2/0 silk using simple interrupted suture pattern. were considered significant. Post - surgical care : On comp letion of surgery, RESULTS AND DISCUSSION each rabbit was thoroughly dried and returned to its cage where food and water were provided. Assessment of the duration of analgesia and Penicillin (0.5 mg/kg body weight) and anaesthesi a as presented in Table 1 showed streptomycin (1 mg/kg body weight) were that duration of analgesia and anaesthesia of injected intramuscularly once daily for 5 days the P/D/K group were significantly shorter post surgery to all the rabbits. After post - ( p <0.05) compared to that of D/K group. These operative pain assessments at 90 min utes in results suggest ed that pre - anaesthetic both groups, pentazocine (5 mg/kg body administration of pentazocine shortened the weight) was administered intramuscularly after durat ions of analgesia and anaesthesia laparotomy and subsequently once daily for produced by diazepam/ketamine combination. another 2 days to rabbits in both groups. Apparently it appear ed that pentazocine shortened the short duration of D/K anaesthesia Anaesthetic Variables : The following were either due to its stimulant effect on the central studied intra and post operatively . nervous system (CNS) or due to its antago nist effect on ketamine. Central nervous system Induction time: Time from end of ketamine excitation has been reported following the use injection to onset of recumbency.