MATERIALS AND METHODS

MATERIALS AND METHODS
We assembled a clinical practice guideline update committee
of 4 senior ketamine researchers, including the 2 authors of the
previous version. We limited our panel to emergency physicians
because the ED is the exclusive focus of this guideline,
emergency physicians have a widely accepted leadership role in
procedural sedation and analgesia,10,11,21 and emergency
physicians have a natural reluctance to permit other specialists
to dictate emergency medical practice.22
To perform this update, we searched MEDLINE from
January 2003 to November 2010, using the single search term
“ketamine,” manually searched the tables of contents of the
leading emergency medicine and anesthesiology journals during
the same period, and searched the reference lists of all identified
articles for additional relevant articles. Pertinent resulting articles
were reviewed by the committee, and their merits were debated by
e-mail and during a group meeting on September 12, 2010.
We graded the availability and strength of scientific evidence
from the medical literature, using descriptive terms adapted
from the American Society of Anesthesiologists9:
● Supportive: There is sufficient quantitative information from
adequately designed studies to describe a compelling relationship
between a clinical intervention and a clinical outcome.
● Suggestive: There is enough information from case reports and
descriptive studies to provide a directional assessment of the
relationship between a clinical intervention and a clinical outcome.
● Inconclusive: Published studies are available, but they cannot
be used to assess the relation between a clinical intervention
and a clinical outcome because the studies do not provide a
clear causal interpretation of findings or because of research
design or analytic concerns.

● Insufficient: There are too few published studies to
investigate a relationship between a clinical intervention and
clinical outcome.
● Silent: No studies that address a relationship of interest were
found in the available published literature.