Ver el código de «Ketamine»

==General==
*Type: [[Sedation (main)|Dissociative anesthetic]]
*Dosage Forms: 10, 50, 100mg/ml
*Routes of administration: IV, IM, IN
*Common Trade Names: Ketalar

==Adult Dosing==
===Procedural Sedation or Induction===
'''Options:'''
*1-2mg/kg IV, followed by 0.5-1mg/kg IV PRN
*4-5mg/kg IM → repeat 2-4mg/kg IM after 10 min if first dose unsuccessful

===Subdissociative [[Analgesia]]===
*0.1-0.3mg/kg IV PRN<ref>Morton NS. Ketamine for procedural sedation and analgesia in pediatric emergency medicine: a UK perspective. Paediatr Anaesth. 2008;18:25-29</ref><ref>Ahern TL, et al. The first 500: initial experience with widespread use of low-dose ketamine for acute pain management in the ED. Am J Emerg Med. 2015 Feb;33(2):197-201. PMID: 25488336. </ref>
*Consider giving dose in 100 mL NS bag over 15 min to avoid negative sedation side effects<ref>Motov S, Mai M, Pushkar I, et al. A prospective randomized, double-dummy trial comparing IV push low dose ketamine to short infusion of low dose ketamine for treatment of  pain in the ED. Am J Emerg Med. 2017;35(8):1095-1100</ref>

===[[Combative patient]] and/or [[Excited delirium]]===
*4-6mg/kg IM or 1mg/kg IV<ref>Ketamine as Rescue Treatment for Difficulty-to-Sedate Severe Acute Behavioral Disturbance in the ED. Annals of EM. May 2016 67(5):581-587</ref>

===Ketamine Infusion<ref>Miller AC et al. Continuous intravenous infusion of ketamine for maintenance sedation. Minerva Anesth 2011;77:812-20.</ref>===
*Post-intubation sedation start at 1-2mg/kg/hr
**Titrate by 0.5mg/kg/hr q5 min
**Max dose of 4-6mg/kg/hr
*Field, austere drip<ref>BASIC KETAMINE INFUSION ANAESTHESIA. www.scancrit.com. May 31, 2012. http://www.scancrit.com/2012/05/31/ketamine-infusion-anaesthesia/.</ref>
**Place 500mg ketamine in 500 cc for 1mg/ml
**Standard maxi drip sets between 10-20 ggt/ml
***Usually 20 gtt
***Mini drip set has 60 ggt/ml
**For quick drip set with 20 ggt/ml
***Use patient's weight in kg (70 kg for example)
***Drip in the same number of drops per min (3.5mg/min = 210mg/hr = 3mg/kg/hr)

==Pediatric Dosing==
===Procedural Sedation or Induction===
*1.5-2mg/kg IV '''OR'''
*4-5mg/kg IM<ref>Green S. et al. What is the optimal dose of intramuscular ketamine for pediatric sedation?. Acad Emerg Med. 1999 Jan;6(1):21-6</ref> '''OR'''
*3-6mg/kg IN<ref>Hall, D, et al. Intranasal ketamine for procedural sedation. Emerg Med J. 2014; 31:789-90.</ref> '''OR'''

==Special Populations==
*[[Drug Ratings in Pregnancy|Pregnancy Rating]]: B 
*[[Lactation risk categories|Lactation risk]]: Infant risk cannot be ruled out
*Renal dosing: not defined
*Hepatic dosing: reduce doses, increased duration of action

==Contraindications==
*Allergy to class/drug

===Absolute===
*<3 month old 
*Known or suspected schizophrenia, even if currently stable or controlled with medications

===Relative===
*Major procedures involving posterior pharynx (e.g. endoscopy) 
**Typical minor ED oropharyngeal procedures are okay 
*Airway instability (e.g. tracheal stenosis, tracheal surgery) 
*Active pulmonary infection, including URI or asthma (unless for induction) 
*CAD, hypertension, CHF 
*CNS masses, hydrocephalus (head trauma okay) 
*Glaucoma/acute globe injury 
*Thyroid disorder or on thyroid medication

==Adverse Reactions==
[[File:Larsons_point.png|thumb|Apply pressure inwardly and anteriorly to the point labeled "Pressure Point" (Larson's Point) while applying a jaw thrust to relieve laryngospasm <ref>Larson CP Jr. Laryngospasm--the best treatment. Anesthesiology. 1998 Nov;89(5):1293-4. doi: 10.1097/00000542-199811000-00056. PMID: 9822036.</ref>]]
*[[Laryngospasm]] (0.3%)
**Usually associated with large doses or rapid IV push
**Treatment:
**#Jaw thrust
**#Place pressure on Larson's notch
**#If jaw thrust and pressure are not sufficient, bag valve mask with PEEP
**#If above do not resolve laryngospasm, sedate more deeply (propofol is the traditional choice, 0.5mg/kg)
**#If deeper sedation does not resolve laryngospasm, paralyse and intubate
*Apnea or respiratory depression (0.8%)
**Associated with rapid IV push 
**Transient 
*Hypersalivation (rare)
**Can pretreat with [[atropine]] or [[glycopyrrolate]]<ref>Green SM et al. Anticholinergics and ketamine sedation in children: A secondary analysis of atropine versus glycopyrrolate. Acad Emerg Med 2010 Feb; 17:157.</ref>
*Emesis, usually well into recovery (8.4%)
*Recovery agitation, aka emergence reaction (mild in 6.3%, clinically important in 1.4%)
**Can pretreat with midazolam 0.05mg/kg (2-4mg for most adults)<ref>Sener S, Eken C, Schultz CH, Serinken M, Ozsarac M. Ketamine with and without  midazolam for emergency department sedation in adults: a randomized controlled trial. Ann Emerg Med. 2011 Feb;57(2):109-114.e2</ref>
*Muscular hypertonicity and random, purposeless movements (common)
*Clonus, hiccuping, or short-lived nonallergic rash of face and neck

===Intracranial pressure elevation===
*'''Cerebral perfusion pressure (CPP) was compromised only in the patients with pre-existing intracranial hypertension and obstruction to the flow of cerebral spinal fluid.''' This has, however, led to the persistent belief that ketamine is contraindicated in patients with traumatic head injuries. Studies done subsequently have shown, however, that the effects of ketamine on cerebral haemodynamics and ICP are in fact variable and depend on both the presence of additional anaesthetic agents and PaCO2 values.<ref>Filanovsky, Y., Philip Miller et al. Myth: Ketamine should not be used as an induction agent for intubation in patients with head injury. CJEM 2010;12(2):154-7. [http://cjem-online.ca/sites/cjem-online.ca/files/pg154_0.pdf PDF]</ref> Meta-analysis also suggests that Ketamine does not increase ICP and provides favorable hemodynamics.<ref>Wang X et al. Ketamine does not increase intracranial pressure compared with opioids: meta-analysis of randomized controlled trials. J Anesth 2014. PubMed ID: 24859931</ref>

===Neurologic Injury===
*Metaanalysis has shown that when ketamine is used in the presence of controlled ventilation, in conjunction with anaesthetics which reduce cerebral metabolism such as GABA receptor agonists, '''ICP is not increased'''.<ref>Himmelseher S. et al. Revising a dogma: ketamine for patients with neurological injury? Anesth Analg. 2005 Aug;101(2):524-34 [http://www.researchgate.net/publication/7708550_Revising_a_dogma_ketamine_for_patients_with_neurological_injury/file/72e7e529656bccca4f.pdf PDF]</ref>

==Pharmacology==
*Half-life: 2.5 hours
*Metabolism: Hepatic
*Excretion: Urine
*Mechanism of Action: NMDA receptor antagonist

==Comments==
*Give as a slow IV push bolus over 45-60 seconds (rapid bolus increases risk for apnea)
*IV preferred over IM (faster recovery, less emesis) 
*Nystagmus is seen as an effect of the medication

==See Also==
*[[Sedation (Main)]]
*[[Procedural Sedation]]
*[[Intranasal Sedation]]
*[[Delayed sequence intubation]]
*[[Ketofol]]

==References==
<references/>

[[Category:Pharmacology]] [[Category:Critical Care]]

Ketamine: Drug information. UpToDate. www.uptodate.com. Accessed April 2, 2019.