Q&A: Hyponatremia query for clinical indicators

Q: When I was trained as a new CDI specialist, I was told that I could query for hyponatremia with two low sodium (NA) values as a clinical indicator as it shows that while it is not necessarily being treated, hyponatremia is being monitored.

A recent conversation with a senior CDI specialist on our team, however, made me question this approach. I know about pseudo-hyponatremia with hyperglycemia and would never query for hyponatremia with a markedly elevated glucose. My question is if I had a NA of 130 yesterday and a NA of 128 today (both with glucose within normal limits), would these clinical findings qualify as valid clinical indicators to query for hyponatremia?

A: A good general rule of thumb is that queries should be based on at least two indicators, as a query based on one indicator could be looked at as a weak justification for the query (of course, there may be exceptions to this rule). In this case, the two lab values would be just one clinical indicator.

Monitoring without “active intervention” is treatment and can justify a query. Monitoring a significant clinical event can demonstrate the medical decision-making process on the part of the clinical team. Per the Uniform Hospital Discharge Data Set, a condition that requires clinical evaluation may be eligible for reporting.

Clinical evaluation means that the medical staff is aware of the condition and is evaluating it in terms of testing, consultation, and clinical observation of the patient’s condition. Noting on the history and physical that a patient has a bunion does not mean a bunion is coded.

On the other hand, noting that the patient has chronic kidney disease (CKD) stage 4 means they have a significant condition that affects treatment in terms of issues such as selection of antibiotics and fluid balance. The CKD stage 4 may not be directly treated in a patient with pneumonia, but if it is something the medical staff is managing and taking into account when treating and caring for the patient, it should be coded. The same can be said for hyponatremia.

As you formulate your query, documentation of the Glasgow Coma Scale may be an additional clinical indicator as hyponatremia is a risk factor for injury to the central nervous system due to cerebral edema. As a diagnosis, hyponatremia effects the severity of illness and risk of mortality scores for a patient, and monitoring this condition is a quality of care issue and should be documented and coded as such.

Editor’s note: This question and answer were adapted from a thread on the ACDIS Forum. To learn more about participating on the Forum, click here.