Outpatient Surgery Magazine

Measuring Sedation

Re: “5 Strategies for Better Airway Management” (April, page 49). Dr. Marco’s
admirable article would have been more complete had he included the concept of
measuring as a way to avoid over-sedation. While we have no hard data on what
percentage of anesthesia providers employ benzodiazepines (diazepam or
midazolam) versus propofol for sedation, we know the bispectral index and other level
of consciousness monitors measure propofol. BIS-monitored titration of propofol lets
the anesthesia provider dial up whatever level of sedation is desired for a particular
procedure. At BIS 78-85, you can produce minimal sedation for dental work that
requires the patient to open and close his mouth on command. At BIS 70-78, you can
produce moderate or so-called conscious sedation. At BIS 60-70, you can produce
deep sedation. A differentiating point between moderate and deep sedation hinges
on whether passive or active airway intervention is required to maintain the airway.
Passive maneuvers include extending and laterally rotating the patient’s head as well
as placing a liter IV bag under the patient’s shoulders to increase the degree of jaw
extension. Active airway maneuvers include the LMAs described by Dr. Marco as well
as nasal airways. Patient movement at BIS 60-75 (with a zero EMG) means the patient
is receiving adequate propofol and is an indication for more local. The ability to
provide adequate local analgesia is critical to opioid avoidance.