Toxicology test-ordering patterns in a large urban general hospital during five years: an update.

Analytical data from the clinical toxicology laboratory of a large urban hospital, the Los Angeles County--University of Southern California Medical Center, are reported for the year 1976 and are compared to similar data previously documented for the year 1972. Drugs assayed, number of tests requested, and number of positive results are collated. Data on 58 assays show that the overwhelming majority of the requests continue to be for those tests that were originally classified as tests with 4-h turn-around time in the patient-focused concept for a clinical toxicology service in 1972. Total workload increased by 70%. The number of patients on whom some toxicologic assay was requested doubled in spite of a decrease in the number of patients admitted to the hospital during this five-year period. The data show that assays for some socially and clinically significant drugs--ethanol diazepam, tricyclics, and phencyclidine--increased disproportionally while others remained relatively constant, or even decreased.