The cardiopulmonary effects of anesthetic induction with isoflurane, ketamine-diazepam or propofol-diazepam in the hypovolemic dog

Ferret Sedation and Anesthesia

Providing safe anesthetic events in ferrets can be achieved if fundamental principles in anesthesia are followed. Each phase of the anesthetic, event including preanesthetic, maintenance, and postanesthetic phase, have certain considerations. The anesthetic supervisor or veterinarian providing management should have a firm understanding of the species-specific anatomy, physiology, and common indications of general anesthesia along with perspective of their own experience with ferrets. Ensuring these guidelines are followed will facilitate safe administration of general anesthesia in this species.

Comparative experimental study on two designed intravenous anaesthetic combinations in dogs

The goal of the present study is to design a good anaesthetic program for dogs which can lead to optimal anaesthesia with no or minimal post-operative adverse effects. For this purpose, we designed two anaesthetic combinations and compared their effects in Mongrel dogs: combination 'A' consisting of atropine, xylazine, ketamine plus propofol, and combination 'B' consisting of atropine, diazepam, ketamine plus propofol. The onset and duration of anaesthesia induction, the duration of maintenance as well as the period of recovery were recorded and compared for both combinations. Furthermore, heart rate, respiratory rate, body temperature as well as blood picture were analyzed before and after administration of the proposed anaesthetic regimens. Administration of combination 'A' lead to rapid onset, within seconds, and induction of anaesthesia. The anaesthetic effect was maintained for approximately 29 minutes after injection of propofol. This was followed by very smooth recovery within approximately 68 minutes after induction of anaesthesia. In contrast, a less efficient induction and maintenance of anaesthesia as well as individual variability was observed after administration of combination 'B'. Approximately 14 minutes were needed for anaesthesia induction, which was maintained for 23 minutes after injection of propofol. Furthermore, administration of combination 'B' was associated with alterations in heart rate, body temperature and hematological picture. In conclusion, our results revealed that combined administration of atropine, xylazine, ketamine plus propofol (combination 'A') is considered satisfactory for anaesthesia in dogs with minimal post-operative side effects.

Cardiopulmonary effects of thiopental versus propofol as an induction agent prior to isoflurane anesthesia in chair trained rhesus macaques (Macaca mulatta)

The purpose of this study was to evaluate the effects of thiopental versus propofol on cardiopulmonary functions, when used as an induction agent prior to isoflurane anesthesia in rhesus monkeys. Eight healthy rhesus monkeys weighing 3.72 to 5.7 kg, 4-5 years old, were used in the study. Anesthesia was induced with thiopental or propofol intravenous injection, and then maintained with isoflurane in oxygen for 45 minutes. Cardiopulmonary measurements were obtained before and 5, 15, 30, 45, and 60 minutes after induction. The induction doses of thiopental and propofol were 19.41±0.54 and 9.33±1.02 mg/kg, respectively. In both groups, the values of heart rate, respiratory rate, temperature, systolic blood pressure, mean blood pressure, diastolic blood pressure, pH, and lactate were decreased, while the values of partial pressure of carbon dioxide, partial pressure of oxygen, total carbon dioxide, bicarbonate, oxygen saturation, and base excess in the extracellular fluid were increased, as compared with baseline. Systolic blood pressure was significantly lower in thiopental group compare to propofol group. Induction time was very short in both agents but not revealed a significant difference between both groups. However, recovery time was extremely faster in the propofol group. Our results demonstrated that propofol provides a minor suppression in systolic arterial blood pressure than thiopental sodium. In addition, propofol have a fast recovery effect from the anesthesia as well. Furthermore, it is suggested that thiopental sodium could also be used to induce anesthesia instead of propofol, despite slight more suppression of cardiopulmonary function compared to thiopental sodium.

Perioperative Blood Pressure Control and Management

Blood pressure monitoring and management is a vital part of the perianesthetic period. Disturbances in blood pressure, especially hypotension, can have significant impacts on the well-being of small animal patients. There are a variety of mechanisms present to control blood pressure, including ultra-short-, short-, and long-term mechanisms. Several conditions can contribute to decreased blood pressure, including anesthetics, tension pneumothorax, intermittent positive pressure ventilation, hypoxemia, hypercapnia, surgical positioning, and abdominal distension. If hypotension is encountered, the initial response is to provide appropriate fluid therapy. If this is inadequate, other interventions can be used to increase blood pressure and thereby increase perfusion.

Anaesthetic induction and recovery characteristics of a diazepam-ketamine combination compared with propofol in dogs

Induction of anaesthesia occasionally has been associated with undesirable behaviour in dogs. High quality of induction of anaesthesia with propofol has been well described while in contrast variable induction and recovery quality has been associated with diazepam-ketamine. In this study, anaesthetic induction and recovery characteristics of diazepam-ketamine combination with propofol alone were compared in dogs undergoing elective orchidectomy. Thirty-six healthy adult male dogs were used. After habitus scoring (simple descriptive scale [SDS]), the dogs were sedated with morphine and acepromazine. Forty minutes later a premedication score (SDS) was allocated and general anaesthesia was induced using a combination of diazepam-ketamine (Group D/K) or propofol (Group P) and maintained with isoflurane. Scores for the quality of induction, intubation and degree of myoclonus were allocated (SDS). Orchidectomy was performed after which recovery from anaesthesia was scored (SDS) and times to extubation and standing were recorded. Data were analysed using descriptive statistics and Kappa Reliability and Kendall Tau B tests. Both groups were associated with acceptable quality of induction and recovery from anaesthesia. Group P, however, was associated with a poorer quality of induction (p = 0.014), prolonged induction period (p = 0.0018) and more pronounced myoclonus (p = 0.003), but had better quality of recovery (p = 0.000002) and shorter recovery times (p = 0.035) compared with Group D/K. Diazepam-ketamine and propofol are associated with acceptable induction and recovery from anaesthesia. Propofol had inferior anaesthetic induction characteristics, but superior and quicker recovery from anaesthesia compared with diazepam-ketamine.