Good and effective management of emergency unit (EU)-admitted patients is substantial. Qualitative screening is the first step used for clinical intervention protocol. Although immunoassay is reliable and reproducible for detection of opioids, it often does not detect other substances such as tramadol, oxycodone, buprenorphine, or substances that can lead to false negative or positive reports. The present study evaluated the results of commonly used immunoassay test with the GC/MS/MS protocol developed in our lab. The protocol included screening for common substances abused in the country. Thirty-two samples from patients admitted to EU were screened using both techniques, immunoassay and GC/MS/MS. The screening results were tested for false positives and false negatives. Immunoassay screening showed that tramadol was present in 14 samples, tetrahydrocannabinol (THC) in 14, phenobarbital in 1, and benzodiazepines in 3 samples. There were 5 negative samples. GC/MS/MS showed the presence of tramadol in 26 samples, THC in 19, opiates in 5 and phenobarbital in 4 samples. One sample out of 32 was recorded as positive for tramadol by immunoassay technique while lidocaine and paracetamol were confirmed by GC/MS/MS without detection of tramadol. GC/MS/MS showed that immunoassay screening missed out drug detection particularly tramadol and THC in 12% of test samples. This shows that immunoassay is not recommended for testing drugs such as tramadol and THC. GC/MS/MS represents a reliable and reproducible technique with a rapid and comprehensive protocol applied. It detects most common drugs abused with high accuracy in short time. Thus it is better to recommend the application of the presented protocol in EU to avoid misleading results.
View Full Article