A comparison of respiratory function in pigs anaesthetised by propofol or alfaxalone in combination with dexmedetomidine and ketamine

Pig Sedation and Anesthesia for Medical Research

In clinical veterinary practice, proper training and expertise in anesthesia administration and monitoring are essential. Pigs are suitable experimental animals for many surgical techniques because they are similar in size to humans and have a short reproductive cycle. This makes them ideal for research concerning organ transplantation, cardiovascular surgery, and other procedures that require a large animal model. Sedation and premedication should be administered at the lowest dose to be effective with predictable results and reduced adverse effects, to ensure the safety of both the animal and the team involved in the procedure, with a fast onset and optimizing the induction and maintenance of anesthesia. The goal of induction is to achieve a safe and effective level of anesthesia that ensures patient safety and facilitates research. Most of the time, inhalation anesthesia with endotracheal intubation is the ideal choice for maintenance of anesthesia. The difficulties related to endotracheal intubation of pigs can be overcome by knowing the anatomical peculiarities. Effective analgesia tailored to the specific procedure, the pig's condition, and individual responses to medications should complete the maintenance and recovery protocols, reducing perioperative complications.

Establishment and validation of intravenous anesthesia with dexmedetomidine for pigs under assisted spontaneous breathing: A preclinical model of intensive care conditions

Large animal models are frequently used to investigate new medical approaches. In most cases, animals are kept under general anesthesia and mandatory mechanical ventilation during the experiments. However, in some situations assisted spontaneous breathing is essential, e.g. when simulating conditions in a modern intensive care unit. Therefore, we established an anesthesia regime with dexmedetomidine and midazolam/ketamine in porcine models of assisted spontaneous breathing. The total intravenous anesthesia was used in lung healthy pigs, in pigs with oleic acid induced acute respiratory distress syndrome and in pigs with methacholine induced bronchopulmonary obstruction. We were able to maintain stable conditions of assisted spontaneous breathing without impairment of hemodynamic, respiratory or blood gas variables in lung healthy pigs and pigs with induced acute respiratory distress syndrome for a period of five hours and in pigs with induced bronchopulmonary obstruction for three hours. Total intravenous anesthesia containing dexmedetomidine enables stable conditions of assisted spontaneous breathing in healthy pigs, in pigs with induced acute respiratory distress syndrome and in pigs induced bronchopulmonary obstruction as models of intensive care unit conditions.

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.

Clinicophysiological and hematobiochemical effect of dexmedetomidine or diazepam with ketamine and propofol in total intravenous anesthesia in goats

Background

Total intravenous anesthesia (TIVA) is a well-documented anesthetic concept for some animal species, including dogs and horses; however, information about TIVA protocols in goats is currently inadequate. Therefore, this study aimed to compare the clinicophysiological and hematobiochemical effects of dexmedetomidine (DEX) and diazepam premedication with ketamine and propofol.

Result

The DEX-treated group showed a significantly decreased heart rate compared with the diazepam-treated group. Onset of anesthesia and sedation in group I was significantly faster than that in group II (0.33 ± 0.08 and 0.25 ± 0.08 min vs. 3.33 ± 1.53 and 2.0 ± 1.0 min, respectively). Duration of anesthesia and sedation in group I was significantly longer than that in group II (66.67 ± 7.64 and 161.3 ± 43.3 min vs. 37.0 ± 5.19 and 60.33 ± 7.57 min, respectively). The total recovery period in group II was significantly shorter than that in group I (47.0 ± 7.21 vs. 98.33 ± 15.27 min).

Smooth induction and recovery occurred in all goats in group I, whereas most goats in group II exhibited slightly prolonged induction with mild excitation and presence of swallowing reflex and prolonged struggling during recovery.

Conclusion

In TIVA, premedication with DEX produces excellent quality anesthesia, analgesia, sedation, and muscle relaxation. Furthermore, it produces a longer duration of anesthesia, sedation, and analgesia than premedication with diazepam. For these reasons, DEX is more suitable for long surgical procedures, whereas diazepam can be used in minor surgical procedures in goats. Both drug combinations produce hemodynamic stability.