Abstract
Study Objectives
Ketamine is widely used as a procedural sedation agent in pediatrics, where its safety
and efficacy are supported by numerous studies. Emergency physicians use ketamine
infrequently in adults, as it is believed to have a more significant side effect profile
in this population. However, adult data on ketamine use in the emergency medicine
literature are sparse. Our objective was to determine ketamine's adverse effect profile
in adults when used for procedural sedation.
Methods
We performed a literature review based on adverse effect research methodology recommendations.
PubMed, EMBASE, TOXNET, and a variety of specialized databases were queried without
regard to publication date or language. Experts were contacted to locate additional
data.
Inclusion criteria included adult study; ketamine used to facilitate the performance
of painful procedures; dose of at least 1 mg/kg intravenous or at least 2 mg/kg intramuscular;
original data and adverse events reported; spontaneously breathing patient, and no
continuous cotherapies. Studies that met inclusion criteria were abstracted onto structured
forms and their results qualitatively summarized.
Results
Of the 5512 unique citations that were evaluated, 87 met criteria for inclusion. Most
studies were performed in the 1970s and published in the anesthesia literature. Contexts,
end points, and methodological quality varied widely across studies. Ketamine reliably
produces conditions that facilitate the performance of painful procedures. Pharyngeal
reflexes are generally preserved and cardiovascular tone stimulated, including a rise
in blood pressure and myocardial oxygen demand. Laryngospasm and airway obstruction
are reported, and though ketamine is a respiratory stimulant, a brief period of apnea
around the time of injection is common. Reports of significant cardiorespiratory adverse
events are rare, despite ketamine's frequent use in austere, poorly monitored settings.
Dysphoric emergence phenomena occur in 10% to 20% of cases; sedating medications are
effective in preventing and managing these reactions.
Conclusion
When ketamine is used for procedural sedation in adults, emergence phenomena occur
in 10% to 20% of patients. Although providers must be prepared to recognize and manage
airway obstruction, cardiorespiratory adverse events are rare and typically do not
affect outcomes.
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Article Info
Publication History
Accepted:
December 14,
2007
Received:
September 7,
2007
Identification
Copyright
© 2008 Elsevier Inc. Published by Elsevier Inc. All rights reserved.
