Relationship between Tourniquet Pressure and a Cross-Section Area of Superficial Vein of Forearm

This study investigated the appropriate tourniquet pressure (TP) and duration of tourniquet application for venipuncture by calculating the venous cross-section (VCS) area on ultrasonography. Twenty healthy volunteers without cardiovascular risk factors were enrolled in this study. A target vein (either a cephalic or median cubital vein) was selected on ultrasonography. The pneumatic tourniquet was inflated using a rapid cuff inflator system at setting pressure for 120sec. TP strength was varied from 20mmHg to 100mmHg, in 20mmHg increments. The order of TP was randomized. Compari-sons among more than 3 groups were performed by one-way repeated-measures ANOVA and the Bonferroni method. The VCS area increased rapidly until 10sec after tourniquet inflation. The VCS area then increased gradually until 30sec after tourniquet inflation. After that, the VCS area did not increase remarkably. The VCS area increased with TP strength up to 80mmHg, but the VCS area at TP 100mmHg decreased to less than that at TP 40mmHg. Based on these results, we recommend a tourniquet pressure of 60mmHg, and duration of tourniquet application is 30 to 60sec for venipuncture

マッショウ ジョウミャク センシ ニ オケル ジョウミャク ドチョウ ヲ エル タメノ ホウホウ ニ カンスル チョウサ ホウコク

本研究では、前腕で静脈穿刺をする際に、静脈怒張を得るために実際に臨床で行われている方法を明らかにする目的で、質問紙を作成して実態調査を行った。回収率は70.5%であり、このうち309名の回答(有効回答率99.4%)を分析対象とした。静脈怒張を得るために最もよく行う方法として、割合が高い順にマッサージ(20.7%)、温める(20.1%)、クレンチング(18.4%)、叩く(15.9%)、手をしっかり握らせる(13.3%)の5つの方法に1割以上の支持が集まり、マッサージ、温める、叩く方法は、標準採血法ガイドラインが推奨する方法と一致していた。この他には、駆血帯をきつく締め直す方法(4.5%)と腕を下してから駆血する方法(3.6%)を提示したが、支持する人は少数であった。一方、これらの方法を行ったことがある人が感じる主観的効果が最も高かったのは、もっともよく行われるマッサージではなく、温める方法であった。このことから、多忙な臨床現場においては、すぐに実施できる方法を優先する傾向があり、それを試してみてから、手間や時間はかかるが効果のある方法を行っているのではないかと考えられる。また、それぞれの方法における手技は、回答者により様々であることが分かり、今後は、静脈怒張の効果を検証した上で、簡便で確実な手技を示すことが必要と考えられた

ジョウミャク センシ ニ ユウコウ ナ ジョウミャク ドチョウ ヲ エルタメノ テキセツ ナ クケツアツ ト ジョウミャク ドチョウ ニ カンヨスル キャッカンテキ シヒョウ ニツイテ

静脈穿刺時に有効な静脈怒張を得るための適切な駆血圧を検討すると共に、静脈怒張度の客観的指標を得ることを目的に、種々の駆血圧における触知静脈怒張度(怒張度)、および静脈断面積等の変化について検討した。対象者は健常成人46名、マンシェットを上腕に装着し、20〜100mmHgで1分間駆血した。駆血圧は順不同とした。駆血後の怒張度は駆血圧80mmHgまでは増加したが、100mmHgではやや減少した。駆血圧60mmHgと80mmHgの間には怒張度に有意な差がみられなかったが、他の駆血圧間では有意な差がみられた。怒張度は圧迫にて静脈が潰れ始める圧力(静脈触知した時の血管抵抗の指標)、静脈拡張比、静脈断面積の順で相関が高く、皮膚表面から静脈までの距離との間にはやや負の相関がみられた。以上より、駆血圧は60mmHgが適切であり、怒張度の客観的指標としては圧迫にて静脈が潰れ始める圧力が最も適切と考えられた。The purpose of this study was to examine appropriate tourniquet pressure to obtain effective vein distention for venipuncture, and discuss the objective indices for vein distention. Several parameters for vein distention, such as vein cross-section area, were calculated under different tourniquet pressures. Subjects (46healthy adults; 23men, 23women), had a pneumatic tourniquet (width 13cm) applied at the upper arm. and the tourniquet was inflated to 20, 40, 60, 80 or 100mmHg for one minute. The tourniquet pressure was randomized. Venous distention grade by palpation (VDGp) was increased up to 80mmHg of tourniquet pressure, but then slightly decreased at 100mmHg. VDGps for 60 and 80mmHg were not significantly different, but both were significantly higher than that of 20 and 40mmHg. VDGp correlated well with outer pressure, which begins to collapse the vein (index of venous resistance at palpation), the expansion ratio of vein cross-section area before and after tourniquet application, and the vein cross-section area successively.These data suggest that a tourniquet pressure of 60mmHg is appropriate for effective vein distention for venipuncture, and outer pressure, which begins to collapse the vein, is useful for an objective index of vein distention

Wetting Induced Oxidation of Pt-based Nano Catalysts Revealed by In Situ High Energy Resolution X-ray Absorption Spectroscopy

In situ high energy resolution fluorescence detection X-ray absorption spectroscopy (HERFD-XAS) was used to systematically evaluate interactions of H2O and O2 adsorbed on Pt and Pt3Co nanoparticle catalysts in different particle sizes. The systematic increase in oxidation due to adsorption of different species (H2O adsorption <O2 adsorption <O2 + H2O coadsorption) suggests that cooperative behavior between O2 and H2O adsorptions is responsible for the overpotential induced by hydrated species in fuel cells. From the alloying and particle size effects, it is found that both strength of O2/H2O adsorption and their cooperative effect upon coadsorption are responsible for the specific activity of Pt catalysts

Plaque REgression with Cholesterol absorption Inhibitor or Synthesis inhibitor Evaluated by IntraVascular UltraSound (PRECISE-IVUS Trial): Study protocol for a randomized controlled trial

AbstractBackgroundAlthough the positive association between achieved low-density lipoprotein cholesterol (LDL-C) level and the risk of coronary artery disease (CAD) has been confirmed by randomized studies with statins, many patients remain at high residual risk of events suggesting the necessity of novel pharmacologic strategies. The combination of ezetimibe/statin produces greater reductions in LDL-C compared to statin monotherapy.PurposeThe Plaque REgression with Cholesterol absorption Inhibitor or Synthesis inhibitor Evaluated by IntraVascular UltraSound (PRECISE-IVUS) trial was aimed at evaluating the effects of ezetimibe addition to atorvastatin, compared with atorvastatin monotherapy, on coronary plaque regression and change in lipid profile in patients with CAD.MethodsThe study is a prospective, randomized, controlled, multicenter study. The eligible patients undergoing IVUS-guided percutaneous coronary intervention will be randomly assigned to receive either atorvastatin alone or atorvastatin plus ezetimibe (10mg) daily using a web-based randomization software. The dosage of atorvastatin will be increased by titration within the usual dose range with a treatment goal of lowering LDL-C below 70mg/dL based on consecutive measures of LDL-C at follow-up visits. IVUS will be performed at baseline and 9–12 months follow-up time point at participating cardiovascular centers. The primary endpoint will be the nominal change in percent coronary atheroma volume measured by volumetric IVUS analysis.ConclusionPRECISE-IVUS will assess whether the efficacy of combination of ezetimibe/atorvastatin is noninferior to atorvastatin monotherapy for coronary plaque reduction, and will translate into increased clinical benefit of dual lipid-lowering strategy in a Japanese population