Ordering of laboratory work in the management of pediatric burn patients: technical note

A large number of laboratory tests are often ordered in the management of acutely burned patients. Administration of large volumes of fluid and frequent ventilator changes prompt many facilities to utilize ordering protocols. Forty-five consecutive acutely burned pediatric patients with burns measuring 25% or more of total body surface area (TBSA) sustained within 24 hours before admission were reviewed. Laboratory determinations were made at each shift and as indicated by changes in condition. Abnormal or critical values during the first 5 postinjury days were identified for electrolytes, renal function indices, complete blood counts (CBCs), glucose, and arterial blood gas (ABG) levels. Blood drawn for the laboratory tests was also measured. In the first 5 days postburn a total of 8303 laboratory determinations were made. Of these, 186 produced abnormal values. Four were critical values that were not expected from previous determinations. Of the four unexpected critical values obtained, two would have been picked up by our present standard noninvasive monitors. Six percent of estimated blood volume was used to perform laboratory tests. These results demonstrate that significant abnormal laboratory values are uncommon even in severely injured pediatric burn patients and that the ordering of these tests should be individualized based on patient examination and the use of noninvasive monitoring.