Ketamine

Sclerosing cholangitis has been reported in patients on long term ketamine therapy. Ketamine-induced sclerosing cholangitis is potentially reversible with ketamine discontinuation. If signs or symptoms consistent with sclerosing cholangitis (e.g., a cholestatic pattern of increased liver function tests with grossly elevated gamma glutamyl transferase and alkaline phosphatase levels) are observed in a patient receiving ketamine, discontinue ketamine immediately and refer the patient to the appropriate specialist for evaluation. 5.7 Urological Complications Serious renal and urinary complications, including cystitis, reduced bladder capacity, ureteral stenosis, ureteral obstruction, and hydronephrosis have been reported with long-term ketamine use or abuse.

Ureteral stenosis and ureteral obstruction can lead to hydronephrosis and renal impairment and may require emergency interventions such as nephrostomy tube placement, ureteral stenting, or surgical intervention. If signs or symptoms of urinary obstruction or severe lower urinary tract symptoms are observed, discontinue ketamine and refer for urgent urological evaluation. 5.8 Increase in Cerebrospinal Fluid Pressure An increase in intracranial pressure has been reported following administration of ketamine hydrochloride.

Important Dosage and Administration Information Ketamine Hydrochloride Injection should be administered by or under the direction of physicians experienced in the administration of general anesthetics, maintenance of a patent airway, and oxygenation and ventilation. Continuously monitor vital signs in patients receiving Ketamine Hydrochloride Injection.

Emergency airway equipment must be immediately available. Ketamine Hydrochloride Injection is a clear, colorless sterile solution. Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. Discard if product is discolored or contains particulate matter.

Do not administer the 100 mg/mL concentration of Ketamine Hydrochloride Injection intravenously without proper dilution [see Dosage and Administration ] . Must be used immediately after dilution. While some degree of airway protection may be afforded due to active laryngeal-pharyngeal reflexes, vomiting and aspiration may occur with ketamine.

Ketamine Hydrochloride Injection is not recommended for use in patients who have not followed nil per os guidelines. Due to the potential for salivation during Ketamine Hydrochloride Injection administration, administer an antisialagogue prior to induction of anesthesia.

Recommended Dosage and Administration The Ketamine Hydrochloride Injection dosage must be individualized and titrated to the desired clinical effect. If a longer duration of effect is desired, additional increments can be administered intravenously or intramuscularly to maintain anesthesia. However, a higher total dose will result in a longer time to complete recovery.

Induction of Anesthesia Intravenous Route: The initial dose of Ketamine Hydrochloride Injection 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 within 30 seconds following injection is 2 mg/kg. Administer Ketamine Hydrochloride Injection slowly (i.e., over a period of 60 seconds).

Rapid administration may result in respiratory depression and enhanced vasopressor response. The induction dose may be administered as an intravenous infusion at a rate of 0.5 mg/kg/min. Intramuscular Route: The initial dose of Ketamine Hydrochloride Injection administered intramuscularly may range from 6.5 to 13 mg/kg.

A dose of 9 to 13 mg/kg usually produces surgical anesthesia within 3 to 4 minutes following injection, with the anesthetic effect usually lasting 12 to 25 minutes. Administer a benzodiazepine, if clinically indicated, for the prevention of neuropsychological manifestations during emergence from anesthesia. Maintenance of Anesthesia Adjust the maintenance dose according to the patient's anesthetic needs and whether an additional anesthetic agent is administered.

Repeat increments of one-half to the full induction dose as needed for maintenance of anesthesia. Purposeless and tonic-clonic movements of extremities may occur during the course of ketamine anesthesia. These movements do not imply a light plane and are not indicative of the need for additional doses of the anesthetic.

Ketamine Hydrochloride Injection given by slow microdrip infusion technique at a dose of 0.1 to 0.5 mg/minute will maintain general anesthesia in adult patients induced with ketamine. Augment Ketamine Hydrochloride Injection with an intravenous benzodiazepine for the prevention of neuropsychological manifestations during emergence.

Supplement to Other Anesthetic Agents Ketamine Hydrochloride Injection can be administered to supplement other general and local anesthetic agents. Continuously monitor patients for changes in respiratory and hemodynamic parameters. A reduced dose of Ketamine Hydrochloride Injection can be used to produce balanced anesthesia when used in combination with other anesthetic agents.

Preparation of Dilution Induction of Anesthesia : The 100 mg/mL concentration of Ketamine Hydrochloride Injection must be diluted prior to intravenous administration . Dilute the 100 mg/mL concentration of Ketamine Hydrochloride Injection with an equal volume of either Sterile Water for injection, USP, 0.9% Sodium Chloride Injection, USP (Normal Saline), or 5% Dextrose in Water.

Use immediately after dilution. The 50 mg/mL concentration of Ketamine Hydrochloride Injection may be administered intravenously for induction of anesthesia without dilution. The 100 mg/mL concentration of Ketamine Hydrochloride Injection may be administered intramuscularly for induction of anesthesia without dilution. Maintenance of Anesthesia : To prepare a dilute solution containing 1 mg of ketamine per mL, aseptically transfer 10 mL from a 50 mg per mL vial or 5 mL from a 100 mg per mL vial to 500 mL of 5% Dextrose Injection, USP or 0.9% Sodium Chloride Injection, USP (Normal Saline) and mix well.

The resultant solution will contain 1 mg of ketamine per mL. Use immediately after dilution. When fluid restriction is required, Ketamine Hydrochloride Injection can be added to a 250 mL infusion as described above to provide a Ketamine Hydrochloride Injection concentration of 2 mg/mL.