2006 OPEN FORUM Abstracts
THE MISCONCEPTION OF EXPECTED ARTERIAL BLOOD GAS RESULTS IN THE EMERGENCY DEPARTMENT
Anne Schaer, RRT, Tim Frymyer, BS, RRT, David
Mussetter, BA, RRT, Michael Trevino, MS, RRT, Gary Weinstein, MD, FCCP,
Presbyterian Hospital of Dallas, Dallas, Texas.
Background: We
are a large metropolitan teaching hospital. Our emergency department (ED) has
49 beds with an average daily census between 235 - 250 patients. Included in
the ED list of top 25 DRGs are pneumonia, congestive
heart failure, obstructive lung disease such as chronic bronchitis and asthma,
and chest pain. We perform roughly 33,000 arterial blood gases (ABGs) on our
campus per year with approximately 1,250 of those occurring in the ED. The ED
physicians historically have had varied and unpredictable ABG ordering
practices and do not use a standard protocol or algorithm. Staff therapists
report frustration with the ED physicians who seem liberal with their use of
the ABG assessment. This became the motivation for us to ascertain what
percentage of ABGs drawn in the ED is abnormal and/or critical.
Method: We first
determined what constituted a normal blood gas result in our facility by referring
to our policy and procedure manual for ABG normal ranges: pH 7.35 - 7.45, PCO2 35 - 45, PO2 60 - 100, HCO3 22 - 26, BE ±2, SpO2 > 95%. Critical
values were then described as the following: pH <7.20 or >7.60, PO2 < 50, HCO3 < 12 per our policy and procedure manual, as well. We
retrospectively reviewed 420 consecutive ED ABGs over a four month time period.
Twelve results were excluded leaving 408 ABGs for analysis. ABGs were excluded
if the result was:
a) suspected of not being arterial [7] or b) processed two
or more times by the information system [5]. No neonatal blood gases were drawn
in the ED during this time frame.
Results: We found
that 212 (52%) ABGs drawn in our ED were abnormal per our criteria. Within that
abnormal group, 34 were deemed critical by our facility. The remaining 196 (48%)
were described as normal, which included those characterized as being fully
compensated.
Conclusion: The very nature of ED care implies
there will be a high utilization of healthcare resources, especially as they
relate to diagnostic functions. The ED is a prime example of where the "number to treat" is small enough to
justify the high order frequency. The misconception that we draw more normal
than abnormal ABGs at our facility was proven false,
through this simple evaluation of the data. Therefore, we will focus on educating
the staff as it pertains to the information collected. However, additional
evaluation of individual physician's ordering practice might also prove to be
beneficial. There may be some physician's who order an excessive amount of ABGs which offer little clinical significance. The use of
an algorithm may become a result of such a critical evaluation.
THE MISCONCEPTION OF EXPECTED ARTERIAL BLOOD GAS RESULTS IN THE EMERGENCY DEPARTMENT