Wild Tiger Health Project
Created by Dr John C M Lewis

Resources > resource test
hide resource menu

resource test

 

 

Isoflurane. When vaporised in a carrier gas such as oxygen, isoflurane is one of the safest gaseous anaesthetic agents currently used in veterinary medicine. Although carrying substantial amounts of bottled oxygen into the field can be unrealistic, simple equipment can be built that allows the vaporisation of isoflurane in air.

caption-title

In the field, isoflurane and oxygen or air can be used to prolong or deepen anaesthesia, and to smooth ataxic (uncoordinated) or stormy inductions or recoveries which may be experienced.

Dose rateDose rateComments
Ketamine + xylazine6-8 mg/kg ketamine + 0.5 - 1.5 mg/kg xylazineSeizures commonly seen. Control with diazepam or midazolam
Ketamine + xylazine2-4 mg/kg ketamine + 2-3 mg/kg xylazine"Hellabrun mixture" used to reduce dart volume
Medetomidine + ketamine0.05-0.07 mg/kg medetomidine + 3mg/kg ketamineUse lower doses of medetomidine in Sumatran tigers to avoid respiratory depression
Zoletil (Telazol)4-5 mg/kgSlow recoveries
Medetomidine + Zoletil0.015-0.02 mg/kg medetomidine + 1.5-2 mg/kg ZoletilPartially reversible with atipamezole

Isoflurane. When vaporised in a carrier gas such as oxygen, isoflurane is one of the safest gaseous anaesthetic agents currently used in veterinary medicine. Although carrying substantial amounts of bottled oxygen into the field can be unrealistic, simple equipment can be built that allows the vaporisation of isoflurane in air. In the field, isoflurane and oxygen or air can be used to prolong or deepen anaesthesia, and to smooth ataxic (uncoordinated) or stormy inductions or recoveries which may be experienced.

Ketamine hydrochloride is a “dissociative” anaesthetic drug. It causes a chemical separation between the conscious mind, and the sensory and motor control mechanisms of the brain. It produces rapid anaesthesia, and a trance like state. The eyes remain open, the swallowing reflex is maintained, and when used alone, there can be pronounced muscle rigidity, which can cause an increase in body temperature. Excessive salivation and seizures (convulsions) are common side effects. Recovery from ketamine anaesthesia can be prolonged and characterised by ataxia (in-coordination). Although ketamine alone has a wide margin of safety it is best used in combination with a tranquilizer (such as midazolam or diazepam) or sedative (such as medetomidine or xylazine) to overcome the adverse side effects. There is no specific reversal agent for ketamine.

Medetomidine is a very potent sedative drug. Although in all species high doses will produce a sleep-like state with marked muscular relaxation, it should never be used alone to handle dangerous animals as stimulation will cause arousal and animals which appeared to be sedated may react aggressively with little or no warning. The effects of medetomidine can be reversed with atipamezole. Medetomidine is used in combination with low doses of ketamine to produce a reversible state of anaesthesia. While this combination may be used for tigers, there is a significant risk of sudden arousal following minor stimulation, so the animal should be safely restrained with hobbles and depth of anaesthesia monitored more closely than when other anaesthetics or anaesthetic combinations are used. This risk can be significantly reduced by using medetomidine in combination with tiletamine-zolazepam (eg “Zoletil“). Medetomidine is sold under a number of brand names and is usually available as a 1mg/ml solution. Stronger solutions are available in some countries. Medetomidine can cause significant respiratory depression in tigers when used in combination with ketamine.

Drug or drug combinationDose rateComments
Ketamine + xylazine6-8 mg/kg ketamine + 0.5 - 1.5 mg/kg xylazineSeizures commonly seen. Control with diazepam or midazolam
Ketamine + xylazine2-4 mg/kg ketamine + 2-3 mg/kg xylazine"Hellabrun mixture" used to reduce dart volume
Medetomidine + ketamine0.05-0.07 mg/kg medetomidine + 3mg/kg ketamineUse lower doses of medetomidine in Sumatran tigers to avoid respiratory depression
Zoletil (Telazol)4-5 mg/kgSlow recoveries
Medetomidine + Zoletil0.015-0.02 mg/kg medetomidine + 1.5-2 mg/kg ZoletilPartially reversible with atipamezole
  • A

      Isoflurane. When vaporised in a carrier gas such as oxygen, isoflurane is one of the safest gaseous anaesthetic agents currently used in veterinary medicine. Although carrying substantial amounts of bottled oxygen into the field can be unrealistic, simple equipment can be built that allows the vaporisation of isoflurane in air. In the field, isoflurane and oxygen or air can be used to prolong or deepen anaesthesia, and to smooth ataxic (uncoordinated) or stormy inductions or recoveries which may be experienced.

       

  • B

      Ketamine hydrochloride is a “dissociative” anaesthetic drug. It causes a chemical separation between the conscious mind, and the sensory and motor control mechanisms of the brain. It produces rapid anaesthesia, and a trance like state. The eyes remain open, the swallowing reflex is maintained, and when used alone, there can be pronounced muscle rigidity, which can cause an increase in body temperature. Excessive salivation and seizures (convulsions) are common side effects. Recovery from ketamine anaesthesia can be prolonged and characterised by ataxia (in-coordination). Although ketamine alone has a wide margin of safety it is best used in combination with a tranquilizer (such as midazolam or diazepam) or sedative (such as medetomidine or xylazine) to overcome the adverse side effects. There is no specific reversal agent for ketamine.

       

  • C

      I