Analysis of complication risk factors in preoperative computed tomography-guided hookwire location of pulmonary nodules.

BACKGROUND: This study aimed to explore the efficacy of hookwire for computed tomography (CT)-guided pulmonary nodule (PN) localization before video-assisted thoracoscopic surgery (VATS) resection and determine the risk factors for localization-related complications. METHODS: We enrolled 193 patients who underwent preoperative CT-guided PN hookwire localization. The patients were categorized into groups A (103 patients had no complications) and B (90 patients had complications) according to CT and VATS. Uni- and multivariate logistic regression analyses were used to identify risk factors for localization-related complications. A numerical rating scale was used to evaluate hookwire localization-induced pain. RESULTS: We successfully performed localization in 173 (89.6%) patients. Pneumothorax was the main complication in 82 patients (42.5%). Patient gender, age, body mass index, tumor diameter, consolidation tumor ratio, pathologic diagnosis, position adjustment during location, lesion location, waiting time for surgery, and pleural adhesions were not significantly different between the two groups. The number of nodules, number of punctures, scapular rest position, and depth of insertion within the lung parenchyma were significant factors for successful localization. Multivariate regression analysis further validated the number of nodules, scapular rest position, and depth of insertion within the lung parenchyma as risk factors for hookwire-localization-related complications. Hookwire localization-induced pain is mainly mild or moderate pre- and postoperatively, and some patients still experience pain 7 days postoperatively. CONCLUSIONS: Hookwire preoperative PN localization has a high success rate, but some complications remain. Thus, clinicians should be vigilant and look forward to further improvement.

Application of dispersive liquid-liquid microextraction and CE with UV detection for the chiral separation and determination of the multiple illicit drugs on forensic samples.

A new method was developed for pre-concentration, chiral separation and determination of multiple illicit drugs on forensic samples using dispersive liquid-liquid microextraction (DLLME) and capillary electrophoresis (CE) with Ultra Violet (UV) detection. The method was based on the formation of tiny droplets of an organic extractant in the prepared sample solution using water-immiscible organic solvent (chloroform) dissolved in water-miscible organic dispersive solvent (isopropyl alcohol). The organic phase, which extracted heroin, DL-methamphetamine, DL-3, 4-methylenedioxymethamphetamine and dl-ketamine from the prepared sample solution, was separated by centrifuging. The sedimented phase was transferred into a small volume CE auto-sampler vial with 10 µL of 1% HCl methanol solution and evaporated to dryness. The residue was reconstituted in lidocaine hydrochloride aqueous solution (internal standard) and introduced by electrokinetic injection into CE. Parameters affecting extraction efficiency were investigated and optimized. Under optimum conditions, linearity of the method was 0.15-6500 µg/L for all target analytes. The LODs (S/N=3) were 0.05-0.20 µg/L. Excellent repeatability (RSD ≤ 4.4%, n=5) was achieved. The feasibility of this method was demonstrated by analyzing spiked forensic samples. To our knowledge, it is the first time to combine DLLME with CE for chiral separation and determining illicit drugs on forensic samples.

Simultaneous derivatization and extraction of free cyanide in biological samples with home-made hollow fiber-protected headspace liquid-phase microextraction followed by capillary electrophoresis with UV detection.

A new method is reported for the simultaneous derivatization and extraction of free cyanide in biological samples using home-made hollow fiber-protected headspace liquid-phase microextraction (HF-HS-LPME) followed by capillary electrophoresis (CE) determination. The acceptor phase containing Ni(II)-NH(3) (as derivatization agent), sodium carbonate and ammonium pyromellitate (as internal standard) is held within a hollow fiber membrane, affixed to a syringe needle and immersed in the headspace of sample container. The extracted cyanide from the neutral samples forms a stable Ni(CN)(4)(2-) complex which is determined by CE. Parameters affecting extraction efficiency were investigated and optimized. For optimum peak shapes, the capillary was coated with cetyltrimethylammonium bromide (CTAB). The calibration curve was linear for concentrations of CN(-) in the range from 0.1 to 20 micromol L(-1) (R(2)=0.9987). The LOD (S/N=3) was estimated to be 0.01 micromol L(-1) of CN(-) concentration. Such a detection sensitivity is high enough for free cyanide determination in common environmental and biological samples. Excellent repeatability of the extraction (RSD < or = 5.6%, n=5) was achieved. The feasibility of this method was demonstrated by analyzing human urine and saliva samples with spiked recoveries in the range of 92-103.4%. This work provided an efficient alternative to the present headspace microextraction techniques such as headspace solid-phase microextraction (HS-SPME) and headspace single-drop microextraction (HS-SDME).