BACKGROUND In recent years, with the popularity of laryngeal mask airway(LMA) for the management of clinical anesthesia, the influence of the LMA on the position and blood flow of the internal jugular vein(IJV) has at...BACKGROUND In recent years, with the popularity of laryngeal mask airway(LMA) for the management of clinical anesthesia, the influence of the LMA on the position and blood flow of the internal jugular vein(IJV) has attracted an increasing amount of attention.AIM To investigate the effect of placement of different types of LMA(Supreme LMA,Guardian LMA, I-gel LMA) on the position and blood flow of the right IJV.METHODS This was a prospective randomized controlled trial. A total of 102 patients aged 18-75 years who were scheduled to undergo laparoscopic abdominal surgery with general anesthesia were randomly assigned to three groups: Supreme LMA(group 1), Guardian LMA(group 2), and I-gel LMA(group 3) groups. The main indicator was the overlap index(OI) of IJV and the common carotid artery(CCA)at the high, middle, and low points before and after the placement of the LMA.The second indicators were the proportion of ultrasound-simulated needle crossing the IJV and CCA, and the cross-sectional area and blood flow velocity of the IJV before and after placement of the LMA at the middle point.RESULTS Data from 100 patients were included in the statistical analysis. The OI increased significantly after placement of the LMA in the three groups at the three points(P< 0.01), except group 2 at the low point. In group 2 and group 3, the OI was lower than that in group 1 after LMA insertion at the high point(P < 0.0167). At the middle point, after LMA insertion, the proportion of simulated needle crossing the IJV significantly decreased in all three groups(P < 0.05), and the proportion in group 2 was higher than that in group 3(P < 0.0167). The proportion of simulated needle crossing the CCA or both the IJV and CCA significantly increased in group 1 and group 2(P < 0.05), which increased with no statistical significance in group 3. After LMA insertion, the cross-sectional area of the IJV significantly increased, while the blood flow velocity significantly decreased(P <0.01). There was no significant difference among the three groups.CONCLUSION The placement of Supreme, Guardian, and I-gel LMA can increase the OI, reduce the success rate of IJV puncture, increase the incidence of arterial puncture, and cause congestion of IJV. Type of LMA did not influence the difficulty of IJV puncture. Therefore when LMA is used, ultrasound is recommended to guide the IJV puncture.展开更多
This research assesses the speed of blood flow across blood vessels and more specifically the veins in terms of Reynold’s number (laminar flow vs. turbulence flow) and in terms of overall speed of the blood when bein...This research assesses the speed of blood flow across blood vessels and more specifically the veins in terms of Reynold’s number (laminar flow vs. turbulence flow) and in terms of overall speed of the blood when being injected with high-speed saline particles. The authors propose a novel technique to generate accelerated-waved particles built from saline solution to enable the unblocking of partially-blocked healthy-walled veins, and to restore normal operations of these veins. The novel technique encompasses a pump that accelerates saline solutions into the blood stream of the vein and these oscillated waves break down the fats or deposits inside the veins in order to help the blood to flow freely without any obstruction. This research simulated the vein with blood stream using characteristics of the vein in terms of vein diameter, blood density, venous blood flow, and the viscosity of the blood at the normal body temperature. The speed of the overall blood flow after the injection of the accelerated saline droplet solution was determined as well as the depth of penetration of the accelerated particles in order to cleanse the inside of the vein. Results are promising in terms of not altering significantly the overall speed of the bloodstream and also in terms of efficacy of the length of the vein which is being cleaned using this accelerated particle method.展开更多
文摘BACKGROUND In recent years, with the popularity of laryngeal mask airway(LMA) for the management of clinical anesthesia, the influence of the LMA on the position and blood flow of the internal jugular vein(IJV) has attracted an increasing amount of attention.AIM To investigate the effect of placement of different types of LMA(Supreme LMA,Guardian LMA, I-gel LMA) on the position and blood flow of the right IJV.METHODS This was a prospective randomized controlled trial. A total of 102 patients aged 18-75 years who were scheduled to undergo laparoscopic abdominal surgery with general anesthesia were randomly assigned to three groups: Supreme LMA(group 1), Guardian LMA(group 2), and I-gel LMA(group 3) groups. The main indicator was the overlap index(OI) of IJV and the common carotid artery(CCA)at the high, middle, and low points before and after the placement of the LMA.The second indicators were the proportion of ultrasound-simulated needle crossing the IJV and CCA, and the cross-sectional area and blood flow velocity of the IJV before and after placement of the LMA at the middle point.RESULTS Data from 100 patients were included in the statistical analysis. The OI increased significantly after placement of the LMA in the three groups at the three points(P< 0.01), except group 2 at the low point. In group 2 and group 3, the OI was lower than that in group 1 after LMA insertion at the high point(P < 0.0167). At the middle point, after LMA insertion, the proportion of simulated needle crossing the IJV significantly decreased in all three groups(P < 0.05), and the proportion in group 2 was higher than that in group 3(P < 0.0167). The proportion of simulated needle crossing the CCA or both the IJV and CCA significantly increased in group 1 and group 2(P < 0.05), which increased with no statistical significance in group 3. After LMA insertion, the cross-sectional area of the IJV significantly increased, while the blood flow velocity significantly decreased(P <0.01). There was no significant difference among the three groups.CONCLUSION The placement of Supreme, Guardian, and I-gel LMA can increase the OI, reduce the success rate of IJV puncture, increase the incidence of arterial puncture, and cause congestion of IJV. Type of LMA did not influence the difficulty of IJV puncture. Therefore when LMA is used, ultrasound is recommended to guide the IJV puncture.
文摘This research assesses the speed of blood flow across blood vessels and more specifically the veins in terms of Reynold’s number (laminar flow vs. turbulence flow) and in terms of overall speed of the blood when being injected with high-speed saline particles. The authors propose a novel technique to generate accelerated-waved particles built from saline solution to enable the unblocking of partially-blocked healthy-walled veins, and to restore normal operations of these veins. The novel technique encompasses a pump that accelerates saline solutions into the blood stream of the vein and these oscillated waves break down the fats or deposits inside the veins in order to help the blood to flow freely without any obstruction. This research simulated the vein with blood stream using characteristics of the vein in terms of vein diameter, blood density, venous blood flow, and the viscosity of the blood at the normal body temperature. The speed of the overall blood flow after the injection of the accelerated saline droplet solution was determined as well as the depth of penetration of the accelerated particles in order to cleanse the inside of the vein. Results are promising in terms of not altering significantly the overall speed of the bloodstream and also in terms of efficacy of the length of the vein which is being cleaned using this accelerated particle method.
