Seema Khattri Bhandari, James H Nichols
NicCheck I test strips provide a practical and same-day rapid screening tool for nicotine exposure in clinical settings prior to surgery, but the test is less sensitive than LC-MS/MS. NicCheck I test strip performance may be affected by abnormal urine pH.
BACKGROUND: Tobacco use adversely affects surgical outcomes, prompting guidelines for preoperative smoking cessation. Accurate assessment of smoking status is critical, yet self-reporting is often unreliable. Biochemical verification via nicotine metabolites, particularly cotinine, offers objective evaluation. While mass spectrometry provides high sensitivity, point-of-care (POC) tests offer rapid, accessible alternatives. This study assesses the performance of NicCheck I, a CLIA-waived urine test, by comparing its results to liquid chromatography-tandem mass spectrometry (LC-MS/MS) for detecting tobacco exposure in surgical patients.
METHODS: Twenty-four frozen urine samples (12 cotinine-negative, 12 cotinine-positive) were analyzed using NicCheck I test strips and LC-MS/MS. Sample integrity, and pH were assessed using Siemens Multistix 10 SG reagent strips.
RESULTS: NicCheck I correctly identified all negative samples but detected nicotine metabolites in only 9 of 12 LC-MS/MS-confirmed positive samples. False negatives were associated with metabolite concentrations below the NicCheck I detection threshold (200 ng/mL) or urine pH outside the optimal range (4.5 - 8.5) consistent with manufacturer's package insert. LC-MS/MS demonstrated superior sensitivity.
CONCLUSION: NicCheck I test strips provide a practical and same-day rapid screening tool for nicotine exposure in clinical settings prior to surgery, but the test is less sensitive than LC-MS/MS. NicCheck I test strip performance may be affected by abnormal urine pH.