Effect of different types of laryngeal mask airway placement on the right internal jugular vein: A prospective randomized controlled trial

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.