More effective induction of anesthesia using midazolam-butorphanol-ketamine-sevoflurane compared with ketamine-sevoflurane in the common marmoset monkey (Callithrix jacchus)

Evaluation of Anesthetic and Cardiorespiratory Effects after Intramuscular Administration of Three Different Doses of Telazol® in Common Marmosets (Callithrix jacchus)

Marmosets' small body size makes anesthesia challenging. Ideally, small volumes of drugs should be administered intramuscularly (i.m.). In addition, dose-dependent sedation and anesthesia are desirable properties for sedatives and anesthetics in marmosets. Telazol® (tiletamine and zolazepam) is highly concentrated, allowing the use of small injection volumes and dose-dependent sedation and anesthesia. A randomized, blinded study with crossover design in ten healthy adult common marmosets (Callithrix jacchus) was performed to evaluate the anesthetic and cardiorespiratory effects of three doses of i.m. Telazol® (respectively, 5, 10, and 15 mg/kg). Depth of anesthesia, cardiorespiratory effects, and induction, immobilization, and recovery times were determined. A significant difference was observed in immobilization time between 5 and 15 mg/kg of Telazol®. In addition, 15 mg/kg of Telazol® resulted in increased recovery times compared to 5 mg/kg. The cardiorespiratory effects during the first 45 min of immobilization were within clinically acceptable limits. The pedal withdrawal reflex was the best indicator of the anesthetic depth.

The use of midazolam as an appetite stimulant and anxiolytic in the common marmoset (Callithrix jacchus)

BACKGROUND

Food avoidance secondary to disease or stress can lead to weight loss and rapid deterioration of clinical condition in the common marmoset (Callithrix jacchus). Currently, there are no data supporting the use of any pharmaceuticals as an appetite stimulant in this species; however, benzodiazepines are frequently used for this purpose in other species.

METHODS

Six marmosets were used in a crossover study design to evaluate the benzodiazepine midazolam as an appetite stimulant and anxiolytic. Total food intake (TFI) and latency to eat (LTE) were measured following administration of oral and injectable midazolam in non-anxious and anxious states.

RESULTS

Injectable midazolam increased TFI and decreased LTE in anxious marmosets, but had no effect in non-anxious animals. Oral midazolam had no effect on appetite in either state.

CONCLUSIONS

Injectable midazolam may be an effective treatment for anxiety-induced inappetence in marmosets. Individual response to both oral and injectable midazolam may vary.

Magnetic Resonance Imaging of Marmoset Monkeys

The use of the common marmoset monkey (Callithrix jacchus) for neuroscientific research has grown markedly in the last decade. Magnetic resonance imaging (MRI) has played a significant role in establishing the extent of comparability of marmoset brain architecture with the human brain and brains of other preclinical species (eg, macaques and rodents). As a non-invasive technique, MRI allows for the flexible acquisition of the same sequences across different species in vivo, including imaging of whole-brain functional topologies not possible with more invasive techniques. Being one of the smallest New World primates, the marmoset may be an ideal nonhuman primate species to study with MRI. As primates, marmosets have an elaborated frontal cortex with features analogous to the human brain, while also having a small enough body size to fit into powerful small-bore MRI systems typically employed for rodent imaging; these systems offer superior signal strength and resolution. Further, marmosets have a rich behavioral repertoire uniquely paired with a lissencephalic cortex (like rodents). This smooth cortical surface lends itself well to MRI and also other invasive methodologies. With the advent of transgenic modification techniques, marmosets have gained significant traction as a powerful complement to canonical mammalian modelling species. Marmosets are poised to make major contributions to preclinical investigations of the pathophysiology of human brain disorders as well as more basic mechanistic explorations of the brain. The goal of this article is to provide an overview of the practical aspects of implementing MRI and fMRI in marmosets (both under anesthesia and fully awake) and discuss the development of resources recently made available for marmoset imaging.

Current Topics in Marmoset Anesthesia and Analgesia

Anesthetic and analgesics are essential components of both clinical and research procedures completed in marmosets. A review of current anesthetic and analgesic regimens for marmosets has been complied to provide a concise reference for veterinarians and investigator teams. Published dose regimens for injectable and inhalant anesthetic drugs and analgesic drugs are included. Appropriate physiological monitoring is key to the success of the procedure and perianesthetic options are provided. Although recent publications have refined anesthesia and analgesia practices, our review demonstrates the continued need for evidence-based resources specific to marmosets.

Evaluation of anaesthetic and cardiorespiratory effects after intramuscular administration of alfaxalone alone, alfaxalone-ketamine and alfaxalone-butorphanol-medetomidine in common marmosets (Callithrix jacchus)

BACKGROUND

Anaesthesia is often required in common marmosets undergoing various procedures. The aim of this study was to evaluate anaesthetic and cardiopulmonary effects of alfaxalone, alfaxalone-ketamine and alfaxalone-butorphanol-medetomidine in common marmosets.

METHODS

The following treatments were repeatedly administered to seven female common marmosets: Treatment A, alfaxalone (12 mg kg^-1 ) alone; treatment AK, alfaxalone (1 mg animal^-1 ) plus ketamine (2.5 mg animal^-1 ); treatment AMB, alfaxalone (4 mg kg^-1 ), medetomidine (50 µg kg^-1 ) plus butorphanol (0.3 mg kg^-1 ); and treatment AMB-Ati, AMB with atipamezole at 45 minutes.

RESULTS AND CONCLUSIONS

Marmosets became laterally recumbent and unresponsive for approximately 30 minutes in A and AK and for approximately 60 minutes in AMB. The animals showed rapid recovery following atipamezole injection in AMB-Ati. The decrease in heart rate and SpO₂ was significantly greater in AMB compared to A and AK. Oxygen supplementation, anaesthetic monitors and atipamezole should be available especially when AMB is administered.

Comparison of desflurane and sevoflurane on postoperative recovery quality after tonsillectomy and adenoidectomy in children

Comparison of desflurane and sevoflurane on the postoperative recovery quality after tonsillectomy and adenoidectomy in children was carried out. A retrospective analysis was performed on the medical records of 165 children who underwent tonsil and adenoid radiofrequency ablation under low-temperature plasma and were admitted to the Xuzhou Children's Hospital, Xuzhou Medical University from February 2014 to May 2017. In total, 79 children with sevoflurane anesthesia were in the sevoflurane group, and 86 children with desflurane anesthesia in the desflurane group. The non-invasive blood pressure (NIBP), heart rate (HR) and oxygen saturation (SpO₂) level, the postoperative sedation (Ramsay) scores, the modified objective pain score (MOPS) of children were recorded. The pediatric anesthesia emergence delirium (PAED) scores of children were recorded. Children in the sevoflurane group had longer operation time, anesthesia time, extubation time and coincidence time than those in the desflurane group (P<0.05). At the beginning of operation (t1), 10 min after operation (t2), at the time of entering anesthesia recovery room (t3), at the time of tracheal catheter extubated (t4), 10 min after extubation (t5), and at the time of leaving the anesthesia recovery room (t6), children in the sevoflurane had higher NISBP and NIDBP, lower HR than those in the desflurane group (P<0.05). At the time of the tracheal catheter extubation (c2), 10 min after extubation (c3), 30 min after extubation (c4), children in the sevoflurane group had lower Ramsay scores and higher PAED scores than those in the desflurane group (P<0.05). More suitable as an anesthetic maintenance drug for tonsillectomy and adenoidectomy in children, desflurane has a better anesthetic effect and is safer. In addition, children with desflurane anesthesia have high postoperative recovery quality and quick recovery in the short term, with better sedative and analgesic effects. Therefore, it is worthy of promotion in clinic practice.