Cipla Ketalar Injection

Ketamine is a rapid-acting, nonbarbiturate general anaesthetic. It produces an anaesthetic state characterized by profound analgesia. The anaesthetic state produced by Ketamine has been termed “dissociative anaesthesia” (A form of general anaesthesia characterized by catalepsy, catatonia, and amnesia, but not necessarily involving complete unconsciousness).

Ketamine is frequently described as a “unique drug” because it has hypnotic (sleep-producing), analgesic (pain relieving) and amnesic (short-term memory loss) effects- no other drug used in clinical practice combines these three important features. It was first used clinically in 1970, and because of these combined effects, it was thought that it might be the perfect anaesthetic agent.

Onset and Duration: Because of rapid induction following the initial intravenous injection, the patient should be supported during administration. The onset of action of Ketamine is rapid, an intravenous dose of 2 mg/kg of body weight usually produces surgical anaesthesia within 30 seconds after injection, with the anaesthetic effect usually lasting 5 to 10 minutes.

If a longer effect is desired, additional increments can be administered intravenously or intramuscularly to maintain anaesthesia without producing significant cumulative effects. Intramuscular doses, from experience primarily in children, in a range of 9 to 13 mg/kg usually produce surgical anaesthesia within 3 to 4 minutes following injection, with the anaesthetic effect usually lasting 12 to 25 minutes.

Intravenous Route: The initial dose of Ketamine administered intravenously may range from 1 mg/kg to 4.5 mg/kg. The average amount required to produce 5 to 10 minutes of surgical anesthesia has been 2 mg/kg. In adult patients, an induction dose of 1 mg to 2 mg/kg intravenous Ketamine at a rate of 0.5 mg/kg/mm may be used for induction of anaesthesia.

In addition, diazepam in 2 mg to 5 mg doses, administered in a separate syringe over 60 seconds, may be used. In most cases, 15 mg of intravenous diazepam or less will suffice. The incidence of psychological manifestations during emergence, particularly dream-like observations and emergence delirium, may be reduced by this induction dosage program.

Rate of Administration: It is recommended that Ketamine be administered slowly (over 60 seconds). More rapid administration may result in respiratory depression and enhanced pressure response.

Intramuscular Route: The initial dose of Ketamine administered intramuscularly may range from 6.5 to 13 mg/kg. A dose of 10 mg/kg will usually produce 12 to 25 minutes of surgical anaesthesia.

Maintenance of anaesthesia: Increments of one-half to the full induction dose, either IV or IM may be repeated as needed for the maintenance of anaesthesia. Nystagmus, movements in response to stimulation, and vocalization may indicate the lightening of anaesthesia.