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Ji-Hee Lee1,*, Goeun Choi1,*, Yeon-Ji Oh1, Je Won Park1, Young Bin Choy3, Mung Chul Park1, Yeo Joon Yoon1, Hwa Jeong Lee2, Hee Chul Chang4, Jin-Ho Choy1 1Center for Intelligent Nano-Bio Materials (CINBM), Department of Bioinspired Science and Department of Chemistry and Nano Science, 2Division of Life and Pharmaceutical Sciences and College of Pharmacy, Ewha Womans University, Seoul, Korea; 3Department of Biomedical Engineering, College of Medicine and Institute of Medical and Biological Engineering, Medical Research Center, Seoul National University, Seoul, Korea; 4Global Strategy Center and Pharmaceutical Research Institute, Daewoong Pharmaceutical Co., Ltd., Seoul, Korea*These authors contributed equally to this workAbstract: A nanohybrid was prepared with an inorganic clay material, montmorillonite (MMT), for taste masking of sildenafil (SDN). To further improve the taste-masking efficiency and enhance the drug-release rate, we coated the nanohybrid of SDN–MMT with a basic polymer, polyvinylacetal diethylaminoacetate (AEA). Powder X-ray diffraction and Fourier transform infrared experiments showed that SDN was successfully intercalated into the interlayer space of MMT. The AEA-coated SDN–MMT nanohybrid showed drug release was much suppressed at neutral pH (release rate, 4.70 ± 0.53%), suggesting a potential for drug taste masking at the buccal cavity. We also performed in vitro drug release experiments in a simulated gastric fluid (pH = 1.2) and compared the drug-release profiles of AEA-coated SDN–MMT and Viagra®, an approved dosage form of SDN. As a result, about 90% of SDN was released from the AEA-coated SDN–MMT during the first 2 hours while almost 100% of drug was released from Viagra®. However, an in vivo experiment showed that the AEA-coated SDN–MMT exhibited higher drug exposure than Viagra®. For the AEA-coated SDN–MMT, the area under the plasma concentration–time curve from 0 hours to infinity (AUC0-∞) and maximum concentration (Cmax) were 78.8 ± 2.32 µg • hour/mL and 12.4 ± 0.673 µg/mL, respectively, both of which were larger than those obtained with Viagra® (AUC0-∞ = 69.2 ± 3.19 µg • hour/mL; Cmax = 10.5 ± 0.641 µg/mL). Therefore, we concluded that the MMT-based nanohybrid is a promising delivery system for taste masking of SDN with possibly improved drug exposure.Keywords: montmorillonite, nanohybrids, polyvinylacetal diethylaminoacetate, sildenafil citrate, taste masking

The aim of this study was to assess whether the Streamlined Liner of the Pharynx Airway (SLIPA) performed as well as an endotracheal tube for positive pressure ventilation in gynaecological laparoscopic surgery in the Trendelenburg position. Forty patients (American Society of Anesthesiologists physical status I to III) were randomly divided into two groups: SLIPA (n = 20) or endotracheal tube group (n = 20). Lung mechanics and severity of postoperative sore throat were assessed in both groups. In the SLIPA group, the oropharyngeal leak pressure was also measured. There were no significant differences between groups in the lung mechanics. In the SLIPA group, oropharyngeal leak pressure and peak inspiratory pressure increased significantly after gas insufflation compared to 10 minutes after patient positioning in the lithotomy position (P < 0.05). The difference between oropharyngeal leak pressure and peak inspiratory pressure (approximately 10 cmH2O throughout the procedure) remained suitable for airway maintenance. The incidence of sore throat was similar in both groups but the severity was less in the SLIPA group 24 hours after surgery (P < 0.05). There were no other complications such as regurgitation noted in either group. In the study population, the SLIPA performed as well as an endotracheal tube in allowing positive pressure ventilation without gas leak during gynaecological laparoscopy. The way in which the SLIPA increases its resistance to gas leak as the inspiratory pressure rises may account for this. [ABSTRACT FROM AUTHOR]

Background and Objective: The axillary vein is another option for central venous catheterisation, with less chance of accidental arterial puncture as there is a greater distance between artery and vein, and from vein to rib cage, compared with other sites. Better success, lower complication rates and faster access can be achieved with ultrasound guidance which is becoming the established technique for central venous catheterisation. We measured two key factors for successful infraclavicular axillary venous catheterisation: depth and diameter of the infraclavicular axillary vein in its medial part using ultrasound. Methods: We recruited 98 patients, classified according to sex, age and BMI. Groups were divided according to BMI as follows: group 1 (≤20 kg m⁻²), group 2 (20.01-25.00 kg m⁻²) and group 3 (>25 kg m⁻²); and these were further subdivided according to age: 20-39 years, 40-59 years and 60-80 years. The depth and diameter of the infraclavicular axillary vein was measured at a point between the medial third and midpoint of the clavicle. Results: Vein diameter was significantly different between men and women (P = 0.005), whereas depth showed no significant difference. In the BMI subgroups, there was a significant difference in depth (P < 0.001), and a trend to significant difference in diameter (P = 0.056). However, age-specific differences in depth and diameter were not observed. Conclusion: During catheterisation of infraclavicular axillary vein, real-time visualisation of the needle tip when using ultrasound to gauge vein depth and diameter may diminish major complications such as pneumothorax and artery puncture. [ABSTRACT FROM AUTHOR]