Anesthetic which increases intracranial tension
Ref: Ajay Yadav, Short Textbook of Pediatrics 1st edition PG: 76 A Miller Textbook of Anaesthesia. 6th editionExplanation:KetamineCauses Dissociative anesthesiaPhencyclidine derivativeNMDA receptor agonistAnesthetic PropertiesOnset of Action: 30- 60 secondsEarly regain of consciousness after 15- 20 min due to Redistribution Elimination half life: 2-3 hoursStrong analgesic propertyMetabolised in Liver and products exreted in urineNot a muscle relaxantPrimary site of action - Thalamo-neo-cortical projectionsCardiovascular systemIncreases arterial BPIncreases heart rate &Increases cardiac outputIV agent of choice in SHOCKRespiratory systemPotent Bronchodilator,Good induction agent for asthmaticsUpper airway reflexes remain largely intactIncreases salivatory & Tracheo bronchial secretionsUsing glycopyrollate or atropine becomes necessaryCentral Nervous systemIncreases Intracranial pressure and can precipitate seizuresEmergence reactions:These are seen at emergenceVivid dreamingIllusionsExtracorporeal experiences like floatingExcitementConfusionEuphoriaFearHallucinations:Auditory and Visual hallucinations (MC side effect of Ketamine)Treated with Benzodiazepine Other SystemsEye:Increase intraocular tensionPupils dilate moderatelyNystagmusGITIncreases intragastric pressureSalivary secretions increasedMuscluarIncreases muscle toneIncreased non-puposeful movementsDoseCan be given IV. IM. oral. Rectal and intrathecal routeIV - 2mg/kgIM- 5-lGmg/kgAdvantagesInduction Agent of Choice inAsthmaticsShockChildren (Now Sevoflurance is DOC)Constrictive pericarditisCardiac tamponadeCan be used as SOLE agentCan be used safely at remote places and in inexperienced hands since does not depress heart or respirationPreferred agent when patient is in FULL STOMACH (Preserves laryngo-pharyngea! reflexes)Contraindicated inHead injuryICSOLEye injuryOpt hal pathologyIschemic heart diseaseVascular aneurysmPsychiatric diseasesDrug addictsHypertensives
Ketamine
Propofol
Etomidate
Ether
Miscellaneous General Anesthesia