BACKGROUND: Thiamylal sodium is a common anesthetic barbiturate prepared in alkaline solution for clinical use. There is no previously reported study on the effects of barbiturates on the inflammation and proliferation of vascular smooth muscle cells (VSMCs). Here, we examined the effects of clinical-grade thiamylal sodium solution (TSS) on the inflammation and proliferation of rat VSMCs. METHODS: Expression levels of interleukin (IL)-1α, IL-1β, IL-6, and toll-like receptors in rat VSMCs were detected by quantitative reverse transcription-polymerase chain reaction and microarray analyses. The production of IL-6 by cultured VSMCs or ex vivo-cultured rat aortic segments was detected in supernatants by enzyme-linked immunosorbent assay. VSMC proliferation and viability were determined by the water-soluble tetrazolium-1 assay and trypan blue staining, respectively. RESULTS: TSS increased expression of IL-1α, IL-6, and TLR4 in VSMCs in a dose-dependent manner, and reduced IL-1β expression. Ex vivo TSS stimulation of rat aorta also increased IL-6. Low concentrations of TSS enhanced VSMC proliferation, while high concentrations reduced both cell proliferation and viability. Expression of IL-1 receptor antagonist, which regulates cell proliferation, was not increased by TSS stimulation. Exposure of cells to the TSS additive, sodium carbonate, resulted in significant upregulation of IL-1α and IL-6 mRNA levels, to a greater extent than TSS. CONCLUSIONS: TSS-induced proinflammatory cytokine production by VSMCs is caused by sodium carbonate. However, pure thiamylal sodium has an anti-inflammatory effect in VSMCs. TSS exposure to VSMCs may promote vascular inflammation, leading to the progression of atherosclerosis or in-stent restenosis, resulting in vessel bypass graft failure.
Animals ; Aorta ; Atherosclerosis ; Barbiturates ; Carbon ; Cell Proliferation ; Enzyme-Linked Immunosorbent Assay ; Inflammation* ; Interleukin-1 ; Interleukin-6 ; Interleukins ; Muscle, Smooth, Vascular* ; Rats ; RNA, Messenger ; Sodium ; Thiamylal* ; Toll-Like Receptors ; Transplants ; Trypan Blue ; Up-Regulation

BACKGROUND:Ultrasound guidance is commonly used for accessing difficult peripheral veins.For successful access,a tourniquet is required for venodilation.Tourniquets decrease the compressibility and increase the diameter of veins;they also obfuscate artery-vein differentiation on ultrasound.We aimed to establish the upper limit of sphygmomanometer cuff pressure that facilitates artery-vein differentiation during ultrasound-guided peripheral intravenous access. METHODS:We employed the sphygmomanometer cuff as a tourniquet for venodilation and tested it on seven participants at six different levels as follows:0 mmHg,DBP/2,DBP,(DBP+SBP)/2,SBP,and SBP+20 mmHg.We used an ultrasound probe attached to a pressure-measuring instrument to record cross-sectional images of the cubital artery and vein.During ultrasonography,compression was applied to the blood vessels through the skin.The following day,we measured the wrist pulse pressure and observed the oximeter pulse wave at six different tourniquet pressure levels.Repeated-measures analysis of variance(ANOVA)on ranks and Tukey's post-hoc analysis were used for multiple comparisons. RESULTS:Arterial pulsation was maintained at tourniquet pressures between 0 mmHg and(DBP+SBP)/2.However,arterial pulsation decreased or disappeared when the tourniquet pressure reached or exceeded the SBP.Moreover,at this pressure level,the superior compressibility of veins compared to that of arteries was no longer observed.Compression of the artery to 75%and 50%of its original diameter increased arterial pulsation. CONCLUSION:Arterial pulsation and the superior compressibility are useful indicators for differentiating veins from arteries until the tourniquet pressure reaches(DBP+SBP)/2.However,these indicators are not reliable once the tourniquet pressure exceeds the SBP.

BACKGROUND:Ultrasound guidance is commonly used for accessing difficult peripheral veins.For successful access,a tourniquet is required for venodilation.Tourniquets decrease the compressibility and increase the diameter of veins;they also obfuscate artery-vein differentiation on ultrasound.We aimed to establish the upper limit of sphygmomanometer cuff pressure that facilitates artery-vein differentiation during ultrasound-guided peripheral intravenous access. METHODS:We employed the sphygmomanometer cuff as a tourniquet for venodilation and tested it on seven participants at six different levels as follows:0 mmHg,DBP/2,DBP,(DBP+SBP)/2,SBP,and SBP+20 mmHg.We used an ultrasound probe attached to a pressure-measuring instrument to record cross-sectional images of the cubital artery and vein.During ultrasonography,compression was applied to the blood vessels through the skin.The following day,we measured the wrist pulse pressure and observed the oximeter pulse wave at six different tourniquet pressure levels.Repeated-measures analysis of variance(ANOVA)on ranks and Tukey's post-hoc analysis were used for multiple comparisons. RESULTS:Arterial pulsation was maintained at tourniquet pressures between 0 mmHg and(DBP+SBP)/2.However,arterial pulsation decreased or disappeared when the tourniquet pressure reached or exceeded the SBP.Moreover,at this pressure level,the superior compressibility of veins compared to that of arteries was no longer observed.Compression of the artery to 75%and 50%of its original diameter increased arterial pulsation. CONCLUSION:Arterial pulsation and the superior compressibility are useful indicators for differentiating veins from arteries until the tourniquet pressure reaches(DBP+SBP)/2.However,these indicators are not reliable once the tourniquet pressure exceeds the SBP.

BACKGROUND:Ultrasound guidance is commonly used for accessing difficult peripheral veins.For successful access,a tourniquet is required for venodilation.Tourniquets decrease the compressibility and increase the diameter of veins;they also obfuscate artery-vein differentiation on ultrasound.We aimed to establish the upper limit of sphygmomanometer cuff pressure that facilitates artery-vein differentiation during ultrasound-guided peripheral intravenous access. METHODS:We employed the sphygmomanometer cuff as a tourniquet for venodilation and tested it on seven participants at six different levels as follows:0 mmHg,DBP/2,DBP,(DBP+SBP)/2,SBP,and SBP+20 mmHg.We used an ultrasound probe attached to a pressure-measuring instrument to record cross-sectional images of the cubital artery and vein.During ultrasonography,compression was applied to the blood vessels through the skin.The following day,we measured the wrist pulse pressure and observed the oximeter pulse wave at six different tourniquet pressure levels.Repeated-measures analysis of variance(ANOVA)on ranks and Tukey's post-hoc analysis were used for multiple comparisons. RESULTS:Arterial pulsation was maintained at tourniquet pressures between 0 mmHg and(DBP+SBP)/2.However,arterial pulsation decreased or disappeared when the tourniquet pressure reached or exceeded the SBP.Moreover,at this pressure level,the superior compressibility of veins compared to that of arteries was no longer observed.Compression of the artery to 75%and 50%of its original diameter increased arterial pulsation. CONCLUSION:Arterial pulsation and the superior compressibility are useful indicators for differentiating veins from arteries until the tourniquet pressure reaches(DBP+SBP)/2.However,these indicators are not reliable once the tourniquet pressure exceeds the SBP.

BACKGROUND:Ultrasound guidance is commonly used for accessing difficult peripheral veins.For successful access,a tourniquet is required for venodilation.Tourniquets decrease the compressibility and increase the diameter of veins;they also obfuscate artery-vein differentiation on ultrasound.We aimed to establish the upper limit of sphygmomanometer cuff pressure that facilitates artery-vein differentiation during ultrasound-guided peripheral intravenous access. METHODS:We employed the sphygmomanometer cuff as a tourniquet for venodilation and tested it on seven participants at six different levels as follows:0 mmHg,DBP/2,DBP,(DBP+SBP)/2,SBP,and SBP+20 mmHg.We used an ultrasound probe attached to a pressure-measuring instrument to record cross-sectional images of the cubital artery and vein.During ultrasonography,compression was applied to the blood vessels through the skin.The following day,we measured the wrist pulse pressure and observed the oximeter pulse wave at six different tourniquet pressure levels.Repeated-measures analysis of variance(ANOVA)on ranks and Tukey's post-hoc analysis were used for multiple comparisons. RESULTS:Arterial pulsation was maintained at tourniquet pressures between 0 mmHg and(DBP+SBP)/2.However,arterial pulsation decreased or disappeared when the tourniquet pressure reached or exceeded the SBP.Moreover,at this pressure level,the superior compressibility of veins compared to that of arteries was no longer observed.Compression of the artery to 75%and 50%of its original diameter increased arterial pulsation. CONCLUSION:Arterial pulsation and the superior compressibility are useful indicators for differentiating veins from arteries until the tourniquet pressure reaches(DBP+SBP)/2.However,these indicators are not reliable once the tourniquet pressure exceeds the SBP.

BACKGROUND:Ultrasound guidance is commonly used for accessing difficult peripheral veins.For successful access,a tourniquet is required for venodilation.Tourniquets decrease the compressibility and increase the diameter of veins;they also obfuscate artery-vein differentiation on ultrasound.We aimed to establish the upper limit of sphygmomanometer cuff pressure that facilitates artery-vein differentiation during ultrasound-guided peripheral intravenous access. METHODS:We employed the sphygmomanometer cuff as a tourniquet for venodilation and tested it on seven participants at six different levels as follows:0 mmHg,DBP/2,DBP,(DBP+SBP)/2,SBP,and SBP+20 mmHg.We used an ultrasound probe attached to a pressure-measuring instrument to record cross-sectional images of the cubital artery and vein.During ultrasonography,compression was applied to the blood vessels through the skin.The following day,we measured the wrist pulse pressure and observed the oximeter pulse wave at six different tourniquet pressure levels.Repeated-measures analysis of variance(ANOVA)on ranks and Tukey's post-hoc analysis were used for multiple comparisons. RESULTS:Arterial pulsation was maintained at tourniquet pressures between 0 mmHg and(DBP+SBP)/2.However,arterial pulsation decreased or disappeared when the tourniquet pressure reached or exceeded the SBP.Moreover,at this pressure level,the superior compressibility of veins compared to that of arteries was no longer observed.Compression of the artery to 75%and 50%of its original diameter increased arterial pulsation. CONCLUSION:Arterial pulsation and the superior compressibility are useful indicators for differentiating veins from arteries until the tourniquet pressure reaches(DBP+SBP)/2.However,these indicators are not reliable once the tourniquet pressure exceeds the SBP.

BACKGROUND:Ultrasound guidance is commonly used for accessing difficult peripheral veins.For successful access,a tourniquet is required for venodilation.Tourniquets decrease the compressibility and increase the diameter of veins;they also obfuscate artery-vein differentiation on ultrasound.We aimed to establish the upper limit of sphygmomanometer cuff pressure that facilitates artery-vein differentiation during ultrasound-guided peripheral intravenous access. METHODS:We employed the sphygmomanometer cuff as a tourniquet for venodilation and tested it on seven participants at six different levels as follows:0 mmHg,DBP/2,DBP,(DBP+SBP)/2,SBP,and SBP+20 mmHg.We used an ultrasound probe attached to a pressure-measuring instrument to record cross-sectional images of the cubital artery and vein.During ultrasonography,compression was applied to the blood vessels through the skin.The following day,we measured the wrist pulse pressure and observed the oximeter pulse wave at six different tourniquet pressure levels.Repeated-measures analysis of variance(ANOVA)on ranks and Tukey's post-hoc analysis were used for multiple comparisons. RESULTS:Arterial pulsation was maintained at tourniquet pressures between 0 mmHg and(DBP+SBP)/2.However,arterial pulsation decreased or disappeared when the tourniquet pressure reached or exceeded the SBP.Moreover,at this pressure level,the superior compressibility of veins compared to that of arteries was no longer observed.Compression of the artery to 75%and 50%of its original diameter increased arterial pulsation. CONCLUSION:Arterial pulsation and the superior compressibility are useful indicators for differentiating veins from arteries until the tourniquet pressure reaches(DBP+SBP)/2.However,these indicators are not reliable once the tourniquet pressure exceeds the SBP.

BACKGROUND:Ultrasound guidance is commonly used for accessing difficult peripheral veins.For successful access,a tourniquet is required for venodilation.Tourniquets decrease the compressibility and increase the diameter of veins;they also obfuscate artery-vein differentiation on ultrasound.We aimed to establish the upper limit of sphygmomanometer cuff pressure that facilitates artery-vein differentiation during ultrasound-guided peripheral intravenous access. METHODS:We employed the sphygmomanometer cuff as a tourniquet for venodilation and tested it on seven participants at six different levels as follows:0 mmHg,DBP/2,DBP,(DBP+SBP)/2,SBP,and SBP+20 mmHg.We used an ultrasound probe attached to a pressure-measuring instrument to record cross-sectional images of the cubital artery and vein.During ultrasonography,compression was applied to the blood vessels through the skin.The following day,we measured the wrist pulse pressure and observed the oximeter pulse wave at six different tourniquet pressure levels.Repeated-measures analysis of variance(ANOVA)on ranks and Tukey's post-hoc analysis were used for multiple comparisons. RESULTS:Arterial pulsation was maintained at tourniquet pressures between 0 mmHg and(DBP+SBP)/2.However,arterial pulsation decreased or disappeared when the tourniquet pressure reached or exceeded the SBP.Moreover,at this pressure level,the superior compressibility of veins compared to that of arteries was no longer observed.Compression of the artery to 75%and 50%of its original diameter increased arterial pulsation. CONCLUSION:Arterial pulsation and the superior compressibility are useful indicators for differentiating veins from arteries until the tourniquet pressure reaches(DBP+SBP)/2.However,these indicators are not reliable once the tourniquet pressure exceeds the SBP.

BACKGROUND:Ultrasound guidance is commonly used for accessing difficult peripheral veins.For successful access,a tourniquet is required for venodilation.Tourniquets decrease the compressibility and increase the diameter of veins;they also obfuscate artery-vein differentiation on ultrasound.We aimed to establish the upper limit of sphygmomanometer cuff pressure that facilitates artery-vein differentiation during ultrasound-guided peripheral intravenous access. METHODS:We employed the sphygmomanometer cuff as a tourniquet for venodilation and tested it on seven participants at six different levels as follows:0 mmHg,DBP/2,DBP,(DBP+SBP)/2,SBP,and SBP+20 mmHg.We used an ultrasound probe attached to a pressure-measuring instrument to record cross-sectional images of the cubital artery and vein.During ultrasonography,compression was applied to the blood vessels through the skin.The following day,we measured the wrist pulse pressure and observed the oximeter pulse wave at six different tourniquet pressure levels.Repeated-measures analysis of variance(ANOVA)on ranks and Tukey's post-hoc analysis were used for multiple comparisons. RESULTS:Arterial pulsation was maintained at tourniquet pressures between 0 mmHg and(DBP+SBP)/2.However,arterial pulsation decreased or disappeared when the tourniquet pressure reached or exceeded the SBP.Moreover,at this pressure level,the superior compressibility of veins compared to that of arteries was no longer observed.Compression of the artery to 75%and 50%of its original diameter increased arterial pulsation. CONCLUSION:Arterial pulsation and the superior compressibility are useful indicators for differentiating veins from arteries until the tourniquet pressure reaches(DBP+SBP)/2.However,these indicators are not reliable once the tourniquet pressure exceeds the SBP.