Effect of the addition of tramadol to a combination of tiletamine-zolazepam and xylazine for anaesthesia of miniature pigs

Tramadol vs. Lidocaine Administered Intraperitoneally and in Incisional Lines for the Intraoperative and Postoperative Pain Management of Romifidine-Telazol-Anesthetized Swine Undergoing Umbilical Hernia Repair

The aim of the study was to compare the analgesic efficacy of tramadol and lidocaine for local anesthesia during umbilical hernia repair in swine. The study was performed on 66 large white crossbred swine. The swine received a mixture of tiletamine/zolazepam at 5 mg/kg and romifidine at 80 µg/kg, administered intramuscularly. Then, they were divided into three groups (n = 22) that received different treatments with lidocaine at 4 mg/kg and tramadol at 4 mg/kg. The LL group received lidocaine both by infiltration of the surgical planes and intraperitoneally. The LT group received lidocaine by infiltration of the surgical planes and tramadol intraperitoneally. The TT group received tramadol both by infiltration of the surgical planes and intraperitoneally. In all groups, the infiltration of the surgical planes into the umbilical region involved both the skin and muscle planes. Heart rate, noninvasive arterial blood pressure, and respiratory frequency were recorded during surgery. The response to the surgical stimulus was evaluated using a cumulative pain scale (the cut-off point for rescue analgesia was set to 10). Postoperative pain was assessed using the UNESP-Botucatu pig composite acute pain scale (the cut-off point was set to 4). The trend of physiological variables was adequate for patients under anesthesia. No subject required intraoperative and postoperative rescue analgesia. Tramadol could therefore be used for pain management in livestock.

How is depth of anaesthesia assessed in experimental pigs? A scoping review

BACKGROUND

Despite the large number of pigs involved in translational studies, no gold standard depth of anaesthesia indicators are available. We undertook a scoping review to investigate and summarize the evidence that sustains or contradicts the use of depth of anaesthesia indicators in this species.

METHODS

Medline, Embase and CAB abstract were searched up to September 22nd 2022. No limits were set for time, language and study type. Only original articles of in vivo studies using pigs or minipigs undergoing general anaesthesia were included. The depth of anaesthesia indicators reported in the selected papers were divided in two categories: A, indicators purposely investigated as method to assess depth of anaesthesia; B, indicators reported but not investigated as method to assess depth of anaesthesia.

RESULTS

Out of 13792 papers found, 105 were included after the screening process. Category A: 17 depth of anaesthesia indicators were found in 19 papers. Studies were conducted using inhalant anaesthetics as the main anaesthetic agent in the majority of the cases (13/19 = 68.4%), while 3/19 (15.8%) used propofol. The most investigated depth of anaesthesia indicators were bispectral index (8/19 = 42.1%) and spectral edge frequency 95% (5/19 = 26.3%). Contrasting results about the specific usefulness of each depth of anaesthesia indicators were reported. Category B: 23 depth of anaesthesia indicators were found in 92 papers. The most reported depth of anaesthesia indicators were: motor response following a stimulus (37/92 = 40.2%), depth of anaesthesia scores (21/92 = 23.3%), bispectral index (16/92 = 17.8%) and spectral edge frequency 95% (9/92 = 9.8%).

CONCLUSION

Results highlight the lack of scientifically valid and reliable indicators to ensure adequate depth of anaesthesia in pigs.

Comparison of cardiorespiratory and anesthetic effects of ketamine-midazolam-xylazine-sufentanil and tiletamine-zolazepam-xylazine in miniature pigs

Effective and adequate anesthesia is conducive to better restrain for pigs during surgical or diagnostic procedures This study aimed to evaluate cardiorespiratory and anesthetic effects of ketamine-midazolam-xylazine-sufentanil or tiletamine-zolazepam-xylazine as general anesthetics in miniature pigs. In phase 1, one of the combinations was administered intramuscularly to miniature pigs. The KMXS protocol combined 10 mg kg^-1 ketamine, 0.5 mg kg^-1 midazolam, and 2 mg kg^-1 xylazine with 2 μg kg^-1 sufentanil. The TZX protocol combined 2.2 mg kg^-1 tiletamine, 2.2 mg kg^-1 zolazepam, and 1.4 mg kg^-1 xylazine. After treatment, the mean arterial pressure, systolic arterial pressure, diastolic arterial pressure, heart rate, respiratory rate, peripheral hemoglobin oxygen saturation, rectal temperature, and anesthesia quality were recorded. In phase 2, the feasibility of KMXS and TZX as general anesthetics were evaluated for pig castration. In phase 1, both drug combinations provided smooth induction with similar anesthetic effects. The KMXS protocol provided moderate anesthesia for 60–70 minutes in pigs, while the TZX protocol provided 30–45 minutes. In phase 2, castration was completed smoothly in all pigs with little fluctuation in physiological variables. The KMXS protocol is better for medium-term anesthesia, while the TZX protocol is preferable for short-term anesthesia in pigs.

Physiological and Clinical Responses in Pigs in Relation to Plasma Concentrations during Anesthesia with Dexmedetomidine, Tiletamine, Zolazepam, and Butorphanol

Simple Summary

Reliable protocols are needed for short-term anesthesia in pigs. The study’s aim is to identify an anesthetic procedure that, without the use of sophisticated equipment, ensures an acceptable depth and length of anesthesia, a regular spontaneous breathing pattern, and a stable hemodynamic condition for the animal. A total of 12 pigs were given a single intramuscular injection of dexmedetomidine, tiletamine, zolazepam, and butorphanol. To investigate the possibility of prolonging the anesthesia, six of the pigs also received an intravenous dose of the drug combination after one hour. Physiological and clinical responses and drug plasma concentrations were examined. The main results suggest that intramuscular administration of the drug combination provides up to two hours of anesthesia with stable physiological parameters and an acceptable level of analgesia. An intravenous administration of one-third of the original dosage prolonged the anesthesia for another 30 min. Since the pigs were able to breathe spontaneously, none of them were intubated. The study also provides new information about each drug’s plasma concentrations and the impact of the drug combination in pigs. This technique can be used to perform nonsurgical operations or transports when short-term anesthesia is required.

Abstract

Reliable protocols for short-term anesthetics are essential to safeguard animal welfare during medical investigations. The aim of the study was to assess the adequacy and reliability of an anesthetic protocol and to evaluate physiological and clinical responses, in relation to the drug plasma concentrations, for pigs undergoing short-term anesthesia. A second aim was to see whether an intravenous dosage could prolong the anesthesia. The anesthesia was induced by an intramuscular injection of dexmedetomidine, tiletamine-zolazepam, and butorphanol in 12 pigs. In six of the pigs, a repeated injection intravenously of one-third of the initial dose was given after one hour. The physiological and clinical effects from induction to recovery were examined. Plasma concentrations of the drugs were analyzed and pharmacokinetic parameters were calculated. Each drug’s absorption and time to maximal concentration were rapid. All pigs were able to maintain spontaneous respiration. The route of administration did not alter the half-life of the drug. The results suggest that intramuscular administration of the four-drug combination provides up to two hours of anesthesia with stable physiological parameters and an acceptable level of analgesia while maintaining spontaneous respiration. A repeated intravenous injection may be used to extend the time of anesthesia by 30 min.

Effects of Tiletamine-xylazine-tramadol Combination and its Specific Antagonist on AMPK in the Brain of Rats

Introduction

Tiletamine-xylazine-tramadol (XFM) has few side effects and can provide good sedation and analgesia. Adenosine 5’-monophosphate-activated protein kinase (AMPK) can attenuate trigeminal neuralgia. The study aimed to investigate the effects of XFM and its specific antagonist on AMPK in different regions of the brain.

Material and Methods

A model of XFM in the rat was established. A total of 72 Sprague Dawley (SD) rats were randomly divided into three equally sized groups: XFM anaesthesia (M group), antagonist (W group), and XFM with antagonist interactive groups (MW group). Eighteen SD rats were in the control group and were injected intraperitoneally with saline (C group). The rats were sacrificed and the cerebral cortex, cerebellum, hippocampus, thalamus, and brain stem were immediately separated, in order to detect AMPKα mRNA expression by quantitative PCR.

Results

XFM was able to increase the mRNA expression of AMPKα1 and AMPKα2 in all brain regions, and the antagonist caused the opposite effect, although the effects of XFM could not be completely reversed in some areas.

Conclusion

XFM can influence the expression of AMPK in the central nervous system of the rat, which can provide a reference for the future development of anaesthetics for animals.

Atipamezole Attenuated Telazol/Xylazine-Induced Expression of C-Fos in Rat Thalamencephal and Cerebral Cortex

The aim of this study was to assess whether atipamezole can restrain telazol/xylazine induced expression of c-fos in the rat brain. Rats were injected with a mixture of 13.81 mg/kg telazol and 5.21 mg/kg xylazine, following 10 min later 0.522 mg/kg atipamezole. Thereon, the thalamencephal and cerebral cortex were removed one hour after the last injection. The level of Fos protein was measured in the brain tissue by Westernblot. The results revealed that atipamezole attenuates telazol/xylazine induction of c-fos expression in the thalamencephal and cerebral cortex. The results indicated that atipamezole is able to inhibit telazol/xylazine-induced c-fos expression in the rat brain, thus protecting it from nerve damage.

Femoral head ostectomy for the treatment of acetabular fracture and coxofemoral joint luxation in a Potbelly pig

OBJECTIVE

To report the successful surgical treatment of a comminuted left acetabular fracture, a dorsally luxated left femoral head, and avulsion of the ligament of the femoral head by femoral head ostectomy (FHO) and physical therapy in a companion Potbelly pig.

STUDY DESIGN

Case report.

ANIMALS

A 1-year-old, 13 kg, castrated male, companion Potbelly pig.

METHODS

The pig presented with a nonweight bearing left pelvic limb lameness of 3 weeks' duration that was noticed shortly after the pig got caught under a fence. Under general anesthesia a lateral approach was made to the fractured limb. A FHO was performed as described for dogs. Following surgery, a period of physical therapy was initiated based on protocols described for dogs.

RESULTS

The canine surgical procedure with the approach modified for pigs was successfully performed in our pig. Following surgery, the pig was comfortable and weight bearing. A physical therapy regimen of supervised activity, stairs, and water therapy was used to rehabilitate the leg, as well as a weight management protocol to maintain ideal body condition. The owner was highly satisfied with the outcome. Telephone follow-up with the owner at 12 months after surgery revealed no impairment to movement, and the pig was maintaining normal ambulation without lameness. No complications were observed with this case.

CONCLUSION

FHO, as described for dogs, provided a favorable outcome for hip luxation caused by acetabular fracture, luxation, and avulsion of the femoral head ligament in this small size Potbelly pig.

Swine model in transplant research: Review of anaesthesia and perioperative management

Pigs are one of most common animal species to be used in biomedical models due to their many anatomical visceral similarities with humans, particularly with regards to transplantation. Despite this use, in many of the researches in which pigs are selected for transplantation, the anaesthesia used is an adaptation of human anaesthesia and presents some limitations such as a reduced analgesia a limited control in perioperative period. In this review we show some of the most important conditions in the preanaesthetic management and of swine as well as we review of anaesthetic protocols for the most common types of swine model of transplantation.

Comparison of ketamine-dexmedetomidine-methadone and tiletamine-zolazepam-methadone combinations for short-term anaesthesia in domestic pigs

Cardiorespiratory effects, quality of induction, depth of anaesthesia and quality of recovery were compared in pigs anaesthetised with 8 mg/kg ketamine, 20 µg/kg dexmedetomidine and 0.2 mg/kg methadone (KDM, n = 18) or 8 mg/kg tiletamine-zolazepam and 0.2 mg/kg methadone (TZM, n = 9). Anaesthesia with KDM was partially reversed in nine animals with 0.2 mg/kg atipamezole (KDMat). Sedation was observed earlier in the TZM group (47.2 ± 25.3 s) than the KDM group (91.5 ± 37.4 s). Sternal and lateral recumbency were achieved earlier in the TZM group (76.3 ± 36.5 s and 132.1 ± 30.5 s, respectively) than in the KDM group (149.1 ± 58.7 s and 249.2 ± 84.0 s, respectively). PaO2, SaO2 and PaO2:FiO2 were lower in the TZM group (68.7 ± 4.1 mmHg, 93.4 ± 1.4% and 327.2 ± 19.9 mmHg, respectively) than in the KDM group (80.4 ± 5.9 mmHg, 95.7 ± 1.0% and 380.4 ± 25.6 mmHg, respectively). Fshunt and P(A-a)O2 were higher in the TZM group (24.0 ± 11.8% and 31.4 ± 3.8 mmHg, respectively) than in the KDM group (13.4 ± 3.2% and 20.7 ± 7.4 mmHg, respectively). Times from drug injection to first head movements, sternal recumbency and standing/walking were significantly shorter in the KDM group (45.1 ± 10.5, 48.4 ± 12.6 and 54.4 ± 17.8 min, respectively) than in the TZM group (57.8 ± 11.4, 93.1 ± 14.2 and 165.7 ± 56.6 min, respectively). The median recovery score was higher in the TZM group than in the KDMnoat and KDMat subgroups. Both drug combinations provided adequate anaesthesia for minor procedures lasting about 30 min, but TZM was associated with a poor recovery and oxygenation.

Laparoscopic cystostomy in pigs: Technique and comparison with traditional open cystostomy for surgical stress

Cystostomy is a common procedure in veterinary surgery. We describe a technique for laparoscopic cystostomy (LC group; n = 7) in Bama miniature pigs and compare the surgical stress induced by this procedure to open cystostomy (OC group; n = 7). A three-portal approach was used for laparoscopic cystostomy. First, we placed 2 simple interrupted sutures between the ventral body wall and urinary bladder. Then, a purse-string suture was placed in the urinary bladder wall, approximately 1 cm cranially to the two sutures. A stab incision was made at the center of the purse-string suture and a 12-F Foley catheter advanced into the urinary bladder; the suture was then pulled tightly and tied. Again, two interrupted sutures were placed 1 cm cranially to the catheter, between the ventral body wall and the bladder, to establish cystopexy. The extracorporeal portion of the catheter was fixed to the skin by a finger-trap suture. Blood samples were collected to measure the white blood cell count and serum concentrations of cortisol, interleukin-6, and C-reactive protein; follow-up laparoscopy was performed 1 month after the surgery. Laparoscopic cystotomy was successfully performed in all the pigs; the mean operating time was 43 ± 5 min. The levels of the stress markers reflected a lower stress response for LC than OC. Thus, LC appears to be better than OC both in terms of technique and physiological responses elicited, and may be more suitable than OC in the creation of experimental animal models for investigations on urinary diseases and those requiring diversion of urine flow.

Effects of the tiletamine/zolazepam-xylazine-tramadol combination on plasma oxidative status and haematological indicators in miniature pigs

Oxidative stress in the body occurs when the production of free radicals overwhelms the antioxidant defence systems. The aim of this study was to examine the effects of a tiletamine/zolazepam-xylazine-tramadol combination on the antioxidant status, lipoperoxidase and blood cell indicators in eight miniature pigs. Baseline measures were recorded prior to anaesthesia, then the animals were anaesthetized with the combination of tiletamine/zolazepam (3.5 mg/kg), xylazine (1.32 mg/kg), and tramadol (1.8 mg/kg). Blood samples were collected from the anterior vena cava at 15, 30, 60, 90, 120 min, 24 h, and 72 h after anaesthesia. Plasma malondialdehyde, superoxide dismutase, catalase, and glutathione peroxidase concentrations were measured by colorimetry, and red blood cell counts, white blood cell counts, haemoglobin and packed cell volume were determined using an automated cell counter. The results showed that the concentration of malondialdehyde increased significantly at 30 and 60 min after the injection (P< 0.05), whereas glutathione peroxidase and catalase activity increased slightly (P> 0.05) then returned to baseline values after 90 min (P> 0.05). Superoxide dismutase activity increased significantly (P< 0.05) at 30 and 60 min, and then gradually decreased to baseline values after 90 min. Changes in red blood cell counts, haemoglobin and packed cell volume were not significant, while white blood cell count decreased significantly (P< 0.05) at 30 and 60 min. Our study is the first to demonstrate that tiletamine/zolazepam-xylazine-tramadol provide antioxidant effects, which may be proposed for alleviating the stress of examination and research at veterinary clinics or long-distance transportation.