Cocaine screening of parturients without prenatal care: an evaluation of a rapid screening assay.

Illicit drugs are used widely by inner city patients in our society. Because cocaine ingestion can produce life-threatening arrhythmias and interact with anesthetic drugs, it is potentially useful for the anesthesiologist to know a high-risk patient's cocaine status before administering anesthesia. The commonly used methods to detect cocaine abuse, however, often require 1-3 days for laboratory processing. With these tests, anesthesiologists are unable to test for recent cocaine use in an emergency setting. A new rapid latex agglutination assay for urinary metabolites of cocaine (OnTrak Abuscreen; Roche Diagnostic Systems Inc., Branchburg, NJ) was compared with an assay used by many hospital laboratories. The prevalence of cocaine abuse in the group of unregistered parturients was found to be 68%, with the latex agglutination results exactly matching the hospital laboratory results (kappa = 1.0). A sensitive and specific method now exists that allows anesthesiologists to assess cocaine use rapidly, so that they can use this information when planning a patient's anesthetic.