Ketamine for Prehosptial Use: What Took So Long? · Ketamine for Prehosptial Use: What Took So...
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Ketamine for Prehosptial Use: What Took So Long? Christopher Galton, MD NRP FP - C
Transcript of Ketamine for Prehosptial Use: What Took So Long? · Ketamine for Prehosptial Use: What Took So...
Ketamine for Prehosptial Use:
What Took So Long?
Christopher Galton, MD NRP FP-C
Disclosures
I have no financial disclosures
Ketamine is cheap!
The only bad question . . .
Objectives
Highlight the history of ketamine
Discuss the pharmacodynamics
Discuss the kinetics
Assess the value in EMS
Discuss ketamine in our standards
Determine appropriate patient groups
Your Name
Paramedic
Opening on my Soap Box
In the Beginning
Developed by Calvin Stevens in 1962
Trying to improve or replace PCP
First human use on prisoners in 1964
Broad application in Vietnam
Psychiatry research
in the 1970s
All good intentions …
Non-medical use exploded in the 1990s
Began appearing at raves
Also associated with date rape
Schedule III classification assigned 1999
WHO - List of Essential Medications
Pharmacodynamics
NMDA receptor antagonist
Believed to have AMPA agonist activity
Weak µ and K opioid agonists
D2 agonist activity
Inhibits reuptake of neurotansmitters:
Serotin, dopamine, and norepinephrine
Pharmacodynamics
Truthfully . . . we don’t really
know why it works
CNS Pharmacodynamics
Anesthetic
Amnestic
Dissociation
Hallucinogenic
Euphoria
Antidepressant
Analgseic
Interferes with pain
transmission in the
spinal cord
Inhibits nitric oxide
synthase
PNS Pharmacodynamics
Catecholamine
Reuptake is inhibited
Serotonin reuptake inhibition in GI tract
Nausea and vomiting
ß2 adrenergic reception
Bronchodilation
What does all that mean?
Provides potent pain relief
Very good agent for sedation
Moderately good amnestic agent
Moderately good bronchodilator
Pharmacokinetics
Water and lipid soluble
Administration routes include:
IV (100%)
IM (90%)Oral (15-20%)
Topical
IN (25-50%)
SL (30%)
Rectal (30%)
Pharmacokinetics
Onset time
IV - 30 seconds
IM - 3-4 minutes
IN - 5-10 minutes
PO - 30 minutes
Pharmacokinetics
Duration
Analgesic
IV duration 1-2 hours
IM duration 3-4 hours
Anesthetic
IV duration 5-10 min
IM duration 10-20 min
Metabolized by liver into norketamine
Administration Details
Schedule III controlled substance
Stored at room temperature
Available in following concentrations:
10 mg/mL (20 mL)- $ 20 (IV, analgesia)
50 mg/mL (10 mL) - $ 5 (IV, analgesia, RSI)
100 mg/mL (5 mL) - $ 10 (IM, restraint, RSI)
Lexicomp Online, Adult Lexi-Drugs Online, Hudson, Ohio: Wolters Kluwer Clinical Drug Information, Inc.; 2017; 10 May 2017
Administration Details
No renal adjustments
No hepatic adjustments
Compatible with our formularies
No known problems with pregnancy
Crosses the placenta
Laryngeal reflexes remain intact
Ketamine Contraindications
Hypersensitivity
If hypertension could be hazardous
Suspicion of symptomatic aortic aneurysm
Known cerebral AVM with hypertension
Known intracranial hemorrhage with
compensatory hypertension
Ketamine Side Effects
Induces a dissociative state
Emergence reactions Occurs in 10% of patients
Typically presents with mild agitation
Secretions
Nausea and vomiting
Nystagmus
Ketamine Side Effects
Ketamine (Ketalar) increases MAP
Understand the equations
CPP = MAP – ICP
Brain perfusion is adequate
Increased IOP
Wang, Xin; Ding, Xibing; Tong, Yao; et al. "Ketamine does not increase intracranial pressure compared with opioids: meta-analysis of randomized controlled trials". Journal of Anesthesia. May 2014. 28: 7.
Ketamine Side Effects
Sympathomimetic effects
Direct myocardial depression
Bronchodilation
Lowers seizure threshold
Increases cerebral metabolism
Increases cerebral blood flow
Tonic-clonic movements
Ketamine Dosing
Induction of Anesthesia
IV dosing at 2-4 mg/kg
IM dosing at 4-10 mg/kg
Dissociation
IV dosing at 1-2 mg/kg
IM dosing at 2-4 mg/kg
Ketamine Dosing
Sedation
IV dosing at 0.1 to 0.5 mg/min
IV infusion at 15-30 mcg/kg/min
Pain
IV dosing at 0.1-0.2 mg/kg
IV infusion at 5-10 mcg/kg/min
IN dosing at 0.5-1 mg/kg
What does this mean for EMS?
Provides potent pain relief
Very good sedating agent
Moderately good bronchodilator
Moderately good amnestic agent
Which patients?
Analgesia
Chemical restraint
Sedation
Induction
Analgesia
Standard EMS analgesic
Best if used synergistically with opioids
Safe for just about all patients
Analgesic
Reduced post-operative
nausea/vomiting
Reduce wind-up phenomena
Reduce spinal sensitization
Low doses have few psych side effects
Bell, RF; Dahl, JB; Moore, RA; et al. Perioperative ketamine for acute postoperative
pain". Pain, Palliative and Supportive Care Group. Cochrane Database of Systematic Reviews (1): 25 January 2006.
Chemical Restraint
Excited delirium
Dosing
250 mg IM
0.5-1 mg/kg IV
Faster than
haloperidol
Concern for intubation in the ED?
Sedation
Ketamine
IV versus IM
Re-dose as needed . . .
RSI
Multi-systems trauma Safe when used correctly
Facilitated extraction
Procedures
Induction
Agent of choice for DSI
Primary RSI induction agent
Terrible facilitation agent
Stability is all related to the adrenals
Bronchodilation
Asthma exacerbation
COPD exacerbation
Not a first line agent
May work synergistically due to sedation
Dosing is difficult to determine
Reactive airway disease
Increased secretions
Amnesia
Not the best amnestic agent
Not the choice for amnesia alone
1 mg/kg/hr infusion is fairly consistent
Property exploited by recreational use
Every kiss begins with “K”
