Pathology Associates Of Lexington, P.A.

Delta Check Review Policy

Memo

To: Shirley Hilton, Chief Technologist

From: John B. Carter, M. D., Director of Clinical Laboratories

Subject: Delta Check Review Policy

Date: March 21, 2005

It is my impression that the ability of our LIS to flag significant changes in laboratory values ("Delta Checks") is intended to call attention to clinically significant changes that would not otherwise be flagged by Alert Value limits.

Clinically significant Delta Checks should be of sufficient magnitude to warrant prompt clinical intervention, thus requiring prompt notification of the clinical services; in other words, an additional layer of "Alert Value" reporting.

I understand that our LIS can be set to flag Delta Checks either on basis of a percent change or a specific quantitative change.

Several issues need to be addressed to enable a significant streamlining of this otherwise commendable process. (One day's delta check list tallied last week produced >900 flags. Review of this large number of flagged results hazards the process to become meaningless, incorporates a possibility of overlooking a true significant delta flag, as certainly one cannot individually consider and notify anywhere near this large number of flagged results and, in reality, probably cannot accurately review this large a list.)

Some suggestions following a brief initial review:

Delta Check review should be held to comparison with recent values, either within the present admission, or within the most recent (7-10, etc.) days. Occasionally delta flags come up with a comparison several weeks or even months or years previously.
Delta flags may be unnecessary if both values are within the normal range.
I doubt that delta flags are recorded if the new result also triggers an Alert Value response. This would be redundant.
I doubt the need for Delta Checks on RBC indices (MCV, RDW, etc.) and on absolute neutrophil and lymphocyte (etc.) counts if the total WBC is delta checked.
Delta Checks on serum iron levels are meaningless (with reference to a recent laboratory newsletter noting that serum iron values are extremely variable dependent on many factors).
Reviewing a list of delta flagged PSA levels, I do not see the utility of the delta range that is used, nor the utility of this function at all as we're very unlikely to telephone a changed PSA level, anticipating immediate therapeutic intervention.
I would suggest discontinuing delta checks of serum albumin levels, realizing that the nutrition people may be closely monitoring low levels and we can rely on a reasonable alert value flag for purposes of our rapid notification.
The direct bilirubin delta range needs to be modified. The percent change is not useful; We can determine the change within alert value limits which would warrant an alert notification.
Likewise we will discontinue flags on clinically insignificant changes in BUN and creatinine levels, determining a more realistic delta-alert level.
We must remember that all our lab results are promptly reported to the floor and daily added to the Cumulative Summary Report, and limit our manual technologist Delta Check review to those changes which may be so clinically significant as to warrant prompt notification. Significantly streamlining this process will eliminate some unnecessary work and make possible focused attention to those Delta Checks which may be clinically significant.
While flagged much less frequently, on the brief review that I've personally done, I also question the need to delta flag retic counts, sed rates, alk phos levels, and anion gaps.
I wonder if there may be a concept that Delta Checks may be theoretically used to verify integrity of specimen identification. While this may have some merit which, however, will be lost in the review of several hundred delta flags each day, specimen identity should be verified thru other methods.
This process is, of course, very much related to the commendable efforts underway to facilitate "Autoverification" of test results. Let's discuss whatever cost may involve to outsource some of this Autoverification effort to Sunquest if that may be possible.

On a related topic, let's re-discuss phone calling repeat alert values. For example: Thrombocytopenias in chemotherapy patients who are likely to have sustained low platelet counts for clinically obvious reasons. I hope that we're not calling the clinical service on each and every one of these. Please help me think of other examples of repeat alert values which may not be necessary to call.

This is a small, focal topic -- but I think another example of CQI in which we can eliminate some unproductive effort, enabling more focus on more productive efforts.

(posted 06 April 2005)