Ketamine avoidance

Hypnotics. Common hypnotics are thiopental, propofol, midazolam, etomidate, ketamine and inhaled anesthetics. The incidence of hypersensitivity reactions with thiopental is rare. Recently, thiopental was involved in less than 1% of allergic reactions in France [9]. Ever since Cremophor EL, used as a solvent for some non-barbiturate hypnotics, has been avoided, many previously reported hypersensitivity reactions have disappeared. In the last French surveys, reactions to propofol accounted for less than 2.5% of allergic reactions, and reactions to midazolam, etomidate or ketamine appear to be really rare [9]. Finally, no immune-mediated immediate hypersensitivity reaction involving isoflurane, desflurane or sevoflurane has been reported despite their wide use. 

Emergence delirium with restlessness, disorientation and unpleasant dreams or hallucinations may occur for up 24 hours following ketamine administration. Their incidence is reduced by psychological preparation of the patient, avoidance of verbal and tactile stimulation during the recovery period, or by concomitant administration of opioids, benzodiazepines, propofol or physostigmine. However, unpleasant dreams may persist. 

INDIRECT ANAESTHETICS-GENERAL 1. Risk of arrhythmias when inhalational anaesthetics are coadministered with methylphenidate 2. Case report of 1 sedative effect of midazolam and ketamine from methylphenidate 1. Uncertain it is possible that inhalational anaesthetics sensitize the myocardium to sympathetic stimulation 2. Uncertain at present Avoid giving methylphenidate on the day of elective surgery... 

MEMANTINE ANAESTHETICS -GENERAL-KETAMINE t CNS side-effects Additive effects on NMDA receptors Avoid co-administration... 

Intranasal drug delivery This drug delivery provides fast and direct access to systemic circulation without first-pass metabolism. Administration is not easy especially with uncooperative children, but small volumes involved, rapidity of execution, feasibility at home has made it more attractive, particularly for no-needle approach to acute Illnesses. Aerosols with an appropriate device can avoid swallowing and is more precise in terms of dose. Drugs such as benzodiazepines, fentanyl, diamorphine, and ketamine have been used successfully via this route (90). 

Over a period of 9 years, tachycardia and extensor-type seizures were observed in 4 patients taking theophylline or aminophylline, who were initially anaesthetised with ketamine, and later with halothane or enllurane." Based on subsequent study in mice, the authors attributed the seizures to an interaction between ketamine and theophylline or aminophylline, and they suggest that the combination should perhaps be avoided in some, or antiseizure premedication be given to patients at risk. However, these cases come from one isolated report. Note that, in mice, ketamine had no effect on aminophylline-induced seizures. ... 

Drugs that make the urine alkaline (e.g. sodium bicarbonate, carbonic anhydrase inhibitors) will reduce the elimination of memantine. Memantine should be used with caution with other NMDA antagonists, such as amantadine, ketamine and dextromethorphan, or concurrent use should be avoided, because of the theoretical increased risk of adverse effects. Memantine is predicted to interact with other drugs eliminated by the same renal secretion mechanism, but no important interaction was seen with glibenclamide, hydrochlorothiazide, metformin or triamterene. 

Memantine is chemically related to amantadine, and the manufacturer advises that concurrent use should be avoided or undertaken with caution because of the increased risk of adverse CNS-related drug reactions such as psychosis. Although there are no data, an increased risk is also predicted for ketamine and dextromethorphan, which are also NMDA antagonists. Avoidance of, or caution with, concurrent use is advised. 

Avoid escaiation of opioid doses. May substitute with methadone (because ofitsadditionai NMDA-biocking properties). Use of ketamine seems promising... 

Ketamine may be ideal to treat post-operative pain after adenotonsillectomy. It avoids the feared risks of bleeding with NSAIDs and respiratory depression with opioids. Ketamine at a dose of 0.5 mg/kg IV reduces post-operative pain and need for other analgesics. Peritonsillar infiltration at the same dose has a similar effect to the intravenous dose. The time of administration either before the start or the conclusion of surgery has no bearing on the analgesic effect. If prolonged pain is anticipated a ketamine infusion of 0.3 6 mg/kg per h can be started after the administration of a loading dose of 0.5 mg/kg. 

Ketamine is an excellent anesthetic, analgesic, and sedative in specialized settings. It can be used in patients who cannot tolerate barbiturates, in settings where cardiovascular depression must be avoided, and in patients with refractory bronchospasm. It is useful in one-lung ventilation, asthmatic patients, or when there is need for an intramuscular route of administration. It is very helpful in specific situations such as the need for anesthesia in uncontrollable, mentally retarded patients. It can be simply mixed with syrup if oral premedication is desired. 

The effect of ketamine on intracranial pressure remains controversial, but the drug should certainly be avoided in patients with refractory intracranial hypertension. Ketamine may cause nystagmus, diplopia, and lacrimation. It may transiently increase intraocular pressure. 

The hi-dose delivery system for our intransal ketamine product candidate provides non-invasive (i.e. needle-free) administration compared to IV or IM injections, via a rugged, simple to use device that can be patient-administered if necessary. Each disposable device delivers a total of 30 mg ketamine with well-characterized, predictable pharmacokinetics. This approach to delivering subanesthetic doses of ketamine may be particularly advantageous in emergency situations where convenience, speed of drug delivery/onset, and avoidance of accidental needle sticks in healthcare providers are desirable. In addition, our intranasal ketamine product candidate was formulated to minimize neurotoxicity, a question that has been raised regarding the differently formulated ketamine product currently approved for anesthesia. 

The back was shaved, taking care to avoid superficial and deep lesions on the skin. All rats underwent anesthesia by an intramuscular injection of 30 mg/kg of ketamine. It was decided to use 0.5 mL of hydrochloric acid (52 %) applied on the back of the rats for 15 s in a circular area of 2 cm in diameter (Fig. 4.46). 

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