● Use should be avoided in cats with known or suspected hypertrophic cardiomyopathy. Contraindications: ● Increased cerebrospinal fluid (CSF) pressure ● Significant hypertension or heart failure ● Pre-existing seizure disorder ● Intraocular pressure or globe injuries ● Cats suffering from renal or hepatic insufficiency Reversal agent : α -2 antagonist may offer partial antagonism of ketamine in cats and shorten recovery time associated with ketamine overdoses (Parker et al., 2023). To help counter behavioral effects and muscle hypertonicity, ketamine is typically administered in conjunction with other medications such as benzodiazepines and α 2-adrenergic agonists. Other important information: Ketamine is a bronchodilator and may be beneficial in animals suffering from chronic obstructive pulmonary disease or asthma. ● Cesarean section Adverse side effects: ● Respiratory depression may occur following injection of high doses ● Excessive salivation ● Transient apnea ● Vocalization ● Erratic recovery ● Prolonged recovery ● Emesis ● Convulsions ● CNS stimulation ● Tachycardia ● Hypertension or hypotension Reversal agent : None Other important information: ● Minimal analgesia is produced so appropriate analgesics should be administered concurrently. ● Protect and lubricate eyes after administration. Adverse side effects/precautions: ● Dose-dependent cardiovascular, CNS, and respiratory depression ● Some animals demonstrate undesirable behavioral effects such as ataxia, muscle tremors, paddling, opisthotonos, twitching, and face rubbing when receiving alfaxalone, particularly during recovery (Wheeler et al., 2021). Reversal agent : None ● Hyperthyroidism ● Pancreatic deficiencies ● Kidney failure ● Pulmonary dysfunction
● Ketamine in combination with a sedative or tranquilizer is a relatively safe and effective drug for intravenous induction of anesthesia in dogs and cats. ● Provides analgesia but not complete unconsciousness; good for short procedures or combined with other drugs. Onset of action: Rapid onset about 60-90 seconds after IV injection and 10 minutes after IM injection. Precautions/adverse side effects: ● Ketamine is often combined with a benzodiazepine such as diazepam or midazolam to reduce undesirable side effects such as seizure-like activity and muscle rigidity (Weil et al., 2021). ● Some patients experience increased excitement during recovery. Recovery in a quiet, darkened room is recommended. ● Increases intraocular pressure and patient’s eyes remain open, so there is a risk of corneal drying. 3. Tiletamine HCl and Zolazepam HCl Class: Anesthetic tranquilizer combination (Dissociative Anesthesia) Indications: ● Tiletamine is a dissociative agent that produces analgesia, immobilization and general anesthesia. Zolazepam is a benzodiazepine anxiolytic that produces muscle relaxation (Landry et al., 2020). IV for anesthesia induction should be administered slowly, over 30-45 seconds. ● Tiletamine-zolazepam combination can be safely used as a premedication agent, induction for inhalation anesthesia, or an independent anesthetic for short procedures (Kucharski et al., 2021): ○ IM or IV injection for dogs ○ IM injection for cats Onset of action: Within 7-10 minutes after IM injections and within 60 to 90 seconds after IV injection. Contraindications (Kucharski et al., 2021): ● Central nervous system (CNS) diseases such as epilepsy and seizures ● Head trauma ● Penetrative eye trauma ● Cardiovascular abnormalities (hypertrophy cardiomyopathy in cats, arrythmias or conditions where increase of heart rate is inadvisable) Alfaxalone induces anesthesia by acting on the gamma aminobutyric acid subtype A (GABAA) receptors in the central nervous system (CNS). These receptors are ionotropic ligand-gated channels, and GABA is their endogenous ligand. GABA is the main inhibitory neurotransmitter in the CNS (Barlette, 2019). Onset of action: As a short-acting IV anesthetic agent, it causes rapid loss of consciousness within 20–40 seconds of administration. In dogs and cats, however, alfaxalone produces dose- dependent depression of the cardiovascular system following IV administration (Amengual et al., 2013). 4. Alfaxalone Class: Neuroactive steroid Mechanism of action:
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Book Code: VFL1526
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