Laryngeal mask airway insertion in children: comparison between rotational, lateral and standard technique

Background:  The purpose of the study was to compare the success and ease of insertion of three techniques of laryngeal mask airway (LMA) insertion; the standard Brain technique, a lateral technique with cuff partially inflated and a rotational technique with cuff partially inflated.
Methods:  One hundred and sixty-eight ASA I and II children aged 6 months to 6 years undergoing short elective surgical procedures lasting 40–60 min were included in the study. A standard anesthesia protocol was followed for all patients. Patients were randomly allocated into one of the three groups i.e. standard (S), rotational (R) and lateral (L). The primary outcome measure of the study was success rate at the first attempt using three techniques of LMA insertion. Secondary outcomes measures studied were overall success rate, time before successful LMA insertion, complications and maneuvers used to relieve airway obstruction.
Results:  Successful insertion at the first attempt was significantly higher in group R (96%) compared with group L (84%) and group S (80%) ( P  =   0.03). Overall success rate (i.e. successful insertion with two attempts) was 100% for group R, 93% for group L and 87% for group S ( P  =   0.03). Time for successful insertion was significantly lower in group R compared with group L and S ( P  <   0.001). The incidence of complications was lower in group R.
Conclusions:  A rotational technique with partially inflated cuff is associated with the highest success rate of insertion and lowest incidence of complications and could be the technique of first choice for LMA insertion in pediatric patients.     

Total spinal in an infant: can ‘dry taps’ occur with 20G Tuohy needles?

The loss-of-resistance technique was used to place a 20G epidural needle in the lumbar region in an anesthetized and paralyzed infant. There was no cerebrospinal fluid (CSF) leakage and a 24G catheter was inserted through the needle. At end of surgery, when the patient was breathing spontaneously and a bupivacaine bolus was given through the catheter, a total spinal block was identified. A bench test demonstrated that CSF leakage from a 20G needle can be delayed if CSF pressure is low and if air bubbles are present in the needle.     

Reduced injection pressures using a compressed air injection technique (CAIT): an in vitro study

BACKGROUND AND OBJECTIVES: High injection pressures have been associated with intraneural injection and persistent neurological injury in animals. Our objective was to test whether a reported simple compressed air injection technique (CAIT) would limit the generation of injection pressures to below a suggested 1,034 mm Hg limit in an in vitro model. METHODS: After ethics board approval, 30 consenting anesthesiologists injected saline into a semiclosed system. Injection pressures using 30 mL syringes connected to a 22 gauge needle and containing 20 mL of saline were measured for 60 seconds using: (1) a typical "syringe feel" method, and (2) CAIT, thereby drawing 10 mL of air above the saline and compressing this to 5 mL prior to and during injections. All anesthesiologists performed the syringe feel method before introduction and demonstration of CAIT. RESULTS: Using CAIT, no anesthesiologist generated pressures above 1,034 mm Hg, while 29 of 30 produced pressures above this limit at some time using the syringe feel method. The mean pressure using CAIT was lower (636 +/- 71 vs. 1378 +/- 194 mm Hg, P = .025), and the syringe feel method resulted in higher peak pressures (1,875 +/- 206 vs. 715 +/- 104 mm Hg, P = .000). CONCLUSIONS: This study demonstrated that CAIT can effectively keep injection pressures under 1,034 mm Hg in this in vitro model. Animal and clinical studies will be needed to determine whether CAIT will allow objective, real-time pressure monitoring. If high pressure injections are proven to contribute to nerve injury in humans, this technique may have the potential to improve the safety of peripheral nerve blocks.     

小儿睾丸卵黄囊瘤细胞的体外培养及生物学特性研究

目的 采用组织培养技术在体外培养取自人体的睾丸卵黄囊瘤组织,探讨小儿睾丸卵黄囊瘤组织的体外培养方法及生物学特性.方法 采用组织块培养法培养1例睾丸卵黄囊瘤患儿手术的标本,从形态学、细胞生长动力学、肿瘤内分泌、染色体分析、细胞DNA分析等方面初步研究了小儿睾丸卵黄囊瘤细胞的生物学特性.结果 小儿睾丸卵黄囊瘤细胞无论形态学观察,还是功能学测定,均符合卵黄囊瘤细胞的特征,染色体众数39～97条,并具有体外分泌AFP功能.其特有表现为:细胞贴壁生长,呈短梭形或多角形,细胞密集时可多层重叠生长,肿瘤细胞表面有明显的微绒毛,细胞核形态怪异,细胞倍增时间较长.结论 小儿睾丸卵黄囊瘤细胞在体外生长稳定,增殖活跃,肿瘤细胞的纯度较高,可以用于后续的实验研究.

Abstract：

Objective To establish a method for the culture of testicular yolk sac tumor in childhood and then investigate biological characteristics in vitro. Methods One specimen from testicular yolk sac tumor was cultured in vitro. Testicular yolk sac tumor cell lines were studied morphologically and subjected to karyotype analysis, DNA analysis, and tumor formation evaluation. Results Morphological observation and functional analysis show that cell lines have characteristics of testicular yolk sac tumor. The number of chromosomes varied from 39 to 97. Turours were immunostained positively for AFP in vitro and found to form multiple layers with microvilli. The nuclei were variable and bizarre in size and shape. Conclusions Testicular yolk sac tumor cell lines were cultured proliferated in a stable manner in vitro, which provides a convenient and economical object for basic researches on yolk sac tumor in future.     

Dispersive liquid-liquid microextraction,an effective tool for the determination of synthetic cannabinoids in oral fluid by liquid chromatography–tandem mass spectrometry

In the present work, dispersive liquid-liquid microextraction (DLLME) was used to extract six synthetic cannabinoids (JWH-018, JWH-019, JWH-073, JWH-200, or WIN 55,225, JWH-250, and AM-694) from oral fluids. A rapid baseline separation of the analytes was achieved on a bidentate octadecyl silica hydride phase (Cogent Bidentate C₁₈; 4.6 mm × 250 mm, 4 μm) maintained at 37 °C, by eluting in isocratic conditions (water:acetonitrile (25:75, V/V)). Detection was performed using positive electrospray ionization–tandem mass spectrometry. The parameters affecting DLLME (pH and ionic strength of the aqueous phase, type and volume of the extractant and dispersive solvent, vortex and centrifugation time) were optimized for maximizing yields. In particular, using 0.5 mL of oral fluid, acetonitrile (1 mL), was identified as the best option, both as a solvent to precipitate proteins and as a dispersing solvent in the DLLME procedure. To select an extraction solvent, a low transition temperature mixture (LTTM; composed of sesamol and chlorine chloride with a molar ratio of 1:3) and dichloromethane were compared; the latter (100 μL) was proved to be a better extractant, with recoveries ranging from 73% to 101 % by vortexing for 2 min. The method was validated according to the guidelines of Food and Drug Administration bioanalytical methods: intra-day and inter-day precisions ranged between 4 % and 18 % depending on the spike level and analyte; limits of detection spanned from 2 to 18 ng/mL; matrix-matched calibration curves were characterized by determination coefficients greater than 0.9914. Finally, the extraction procedure was compared with previous methods and with innovative techniques, presenting superior reliability, rapidity, simplicity, inexpensiveness, and efficiency.     

红色毛癣菌的基因分型研究

目的 探讨探针与DNA印迹杂交法对红色毛癣菌的基因分型并分析其基因型与来源地区的相关性。方法 用溴化十六烷基三甲铵（CTAB）法提取DNA，以皮肤癣菌的特异性引物NS5[5′-AACTAAAGGAATTGACGGAAG-3′]与ITS4[5′-TCCTCCGCTTATTGATATGC-3′]为引物，以红色毛癣菌的标准菌株为模板，用PCR法扩增出其rDNA部分18S区，ITSI区，5.8S区和ITSⅡ区为探针，用随机引物法将探针标记^32P，用EcoRI酶切基因组DNA，采用DNA印迹的标准流程将酶切的基因组DNA与探针杂交；显示的不同带型，以此作为红色毛癣菌基因分型的依据。结果 所试49株红色毛癣菌（南京21株，大连26株，北京2株）分为20型（A-T型），其中A-C型占48.98%。南京株绝大多数为3条带，大连株大部分为4条带。结论 用ITS区域探针与DNA印迹杂交法对红色毛癣菌基因组分型敏感性强，分辨力高；南京与大连两地区红色毛癣菌DNA分型具有明显差异，DNA分型对红色毛癣菌病的流行病学，临床疗效的判定以及指导用药均具有重要价值。     

Chinese expert consensus on clinical practice of female fertility preservation

Many female fertility preservation-related technologies have recently been developed in response to increasing demand for such treatments. To establish standard...