Overutilization of serum electrolyte determinations in critical care units. Savings may be more apparent than real but what is real is of increasing importance.

Electrolyte (E) utilization by medical and surgical house staff in the critical care units of a community teaching hospital was audited over a two-month period. One hundred forty-five patients involved in 708 patient days had 924 sets of electrolytes (SE). Of the 581 SE that were ordered as an additional set within 24 h, 10% were considered unnecessary and 65% could have had a single E substituted for the complete set. The conclusion of this study and literature review are: (1) Electrolytes are excessively ordered in the management of critical care patients. (2) When additional electrolyte data is required within 24 h, a single electrolyte will usually suffice. (3) Misutilization is equally prevalent among medical house staff and surgical house staff. (4) The cost savings to be realized from improved laboratory utilization are only a small percentage of the potential savings in charges. (5) No single, proven modality has been identified which will consistently, continually, and appropriately decrease laboratory overutilization.