It's impossible to overstate the importance of that feedback, espe-
cially in the outpatient setting, where many procedures are per-
formed under IV sedation or monitored anesthesia care (MAC). The
primary goal of anesthesia is to minimize risks. Capno-
graphy and pulse oximetry do that during procedures done under
light sedation or major surgeries involving general anesthetics. If
your providers aren't using both, they're not providing safe patient
care. It's that simple.
Here's how each monitoring modality works:
• Pulse oximetry measures the percentage of oxygen that's bound
to hemoglobin. It's usually an accurate, non-invasive and reliable way
to monitor the oxygen saturation level (SpO2) of a patient's blood.
The measure is converted into a percentage that's displayed on the
pulse oximeter, usually along with the patient's heart rate. Acceptable
SpO2 ranges from 95% to 100%. Providers will take notice and begin
to take action when the reading starts to decrease and creep toward
90%.
• Capnography measures the partial pressure of CO
2
in each
expired breath. Providers place a sample line, a very thin tube that's
3 to 4 mm in diameter, in the anesthesia machine's breathing circuit
or the patient's oxygen mask. When patients breathe out, CO
2
is cap-
tured in the line and the capnography monitor provides a relative
reading of end tidal CO
2
(ETCO2).
On a capnography monitor, you see a waveform (capnogram) that
represents the real-time reading of a patient's rate of respiration. A
normal waveform appears as a square-shaped or rectangular box and
a numeric reading (capnometry) shows the measurement of exhaled
CO
2
. "Normal" ETCO2 is in the range of 35 to 45 mmHg. In patients
who are spontaneously breathing during deep sedation, you'd attach
the capnography monitor's sample line to the oxygen mask. In that
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