Why not go to a policy of SST for everything - which makes it far easier and does away with the problem???
One place I worked with had terrible problems because the renal unit sent sdamples down at all times of the day bu 9-5 creatinine was measured on a DAX and 5pm - 9am it was analysed on an AXON. The 2 creatinine methds had a 10% difference in the renal patients range which caused no end of problems with dialysis. It is far simple to have a single system...
TIM
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Prof. Tim Reynolds,
Clinical chemistry Dept.,
Queen's Hospital,
Belvedere Rd.,
Burton-on-Trent.
tel: +44 (0) 1283 511511 ext 4035
fax: +44 (0) 1283 593064
email: [log in to unmask]
-----Original Message-----
From: c=GB;a=NHS;p=NHS NATIONAL
INT;dda:RFC-822=ACB-CLIN-CHEM-GEN(a)JISCMAIL.AC.UK;
Sent: 16 January 2001 17:23
To: c=GB;a=NHS;p=NHS NATIONAL
INT;dda:RFC-822=ACB-CLIN-CHEM-GEN(a)JISCMAIL.AC.UK;
Subject: Serum vs Plasma Potassium reference ranges
Realizing that Im revisiting an often visited topic, I now have to poll the
group for its opinion.
My institution is going to a written policy of serum specimens (SST) for
outpatient/outreach patients and plasma specimens (PST) for inpatients.
Because of the differences between plasma and serum potassium reference
ranges and because our LIS cannot easily accomodate two reference ranges for
the same orderable, I recommended that the plasma reference range (3.4 - 5.0
mmol/L) be reported with the following comment:
Listed reference range is for inpatient (plasma) specimens.
Reference range for outpatient (serum) specimens is 3.6 - 5.2
mmol/L.
There is a school of thought within the lab that goes since the difference
(0.2 mmol/L) is within the instrument precision, one reference range without
a comment should be sufficient. I disagree with this belief since I feel
that disregard to the difference between serum and plasma potassium values
with a stated policy of serum specimens for one group of patients and plasma
for another would be misleading to clinicians.
Please reply with your opinion to this issue.
Thank you
David Alter, MD
Spectrum Health
MI
