The effect of passive leg elevation and/or trendelenburg position on the cross-sectional area of the internal jugular vein in infants and young children undergoing surgery for congenital heart disease

Effect of passive leg raising on the cross-sectional area of the right internal jugular vein in patients with obesity: a randomised controlled trial protocol

BACKGROUND

Venous access in patients with obesity presents significant challenges. The success of central venous catheterisation largely depends on the cross-sectional area (CSA) of the internal jugular vein (IJV). While techniques like the Trendelenburg position have been traditionally used to increase IJV CSA, recent studies suggest its ineffectiveness in patients with obesity. Conversely, the potential of the effect of passive leg raising (PLR) has not been thoroughly investigated in this group of patients.

METHODS

This protocol outlines a planned randomised controlled trial to evaluate the effect of PLR on the CSA of the IJV in patients with obesity slated for central venous catheterisation. The protocol involves dividing 40 participants into two groups: one undergoing PLR and another serving as a control group without positional change. The protocol specifies measuring the CSA of the IJV via ultrasound as the primary outcome. Secondary outcomes will include the success rates of right IJV cannulation. The proposed statistical approach includes the use of t-tests to compare the changes in CSA between the two groups, with a significance threshold set at p<0.05.

ETHICS APPROVAL

This study has been approved by the Institutional Review Board of Shanghai Tongren Hospital. All the participants will provide informed consent prior to enrolment in the study. Regarding the dissemination of research findings, we plan to share the results through academic conferences and peer-reviewed publications. Additionally, we will communicate our findings to the public and professional communities, including patient advocacy groups.

TRIAL REGISTRATION NUMBER

ChiCTR: ChiCTR2400080513.

Ultrasonographic Assessment of Anatomic Relationship Between the Internal Jugular Vein and the Common Carotid Artery in Infants and Children After ETT or LMA Insertion: A Prospective Observational Study

Background: Central venous catheterization is used for fluid management and infusion of drugs, but it is difficult to perform and carries a high incidence of complications in infants and children. In adults, the anatomic relationship and the overlap index between the internal jugular vein (IJV) and the common carotid artery (CCA) changed significantly after laryngeal mask airway (LMA) placement. However, there are conflicting results regarding the anatomic relationship between the IJV and the CCA after endotracheal tube (ETT) or LMA insertion in pediatric populations. Aim: The aim of this study was to compare the overlap index and anatomic relationship between the IJV and the CCA in infants and children after ETT or LMA insertion by ultrasonography. Method: This single-center, prospective, observational study including 92 infants and children, aged 1 month to 6 years, were grouped according to the airway devices placed: Group ETT (n = 44) and Group LMA (n = 48). The overlap index and anatomic relationship between the IJV and the CCA before and after airway device insertion at neutral and 30° head rotation position were evaluated by ultrasonography. Results: Before airway device insertion, as the head was rotated 30° to the contralateral side, the overlap index increased significantly on the right side of the neck compared to the neutral head position. In Group ETT, there was no significant difference in the overlap index after intubation in the neutral head position or 30° head rotated position on either side. In Group LMA, the overlap indexes were increased significantly after LMA insertion in the neutral head position on both sides. Likewise, the overlap indexes were increased significantly after LMA insertion in the 30° head rotated position on both sides. The most common positional relationship between the IJV and the CCA was anterolateral (AL) in both the right side and left side in the neutral head position. In Group ETT, the AL position was still the most common position relationship between the IJV and the CCA before and after intubation in the 30° head rotated position. In Group LMA, the anterior (A) position increased significantly after LMA insertion in the left side. In the 30° head rotated position, there was a significant increase to the A position after LMA insertion in both the right side and left side. The change from AL to A was increased after LMA insertion, especially in the 30° head rotated position. Conclusions: The overlap indexes of the IJV and the CCA increased significantly in both sides of the neck after LMA placement in the neutral head position, especially in 30° head rotated position. The IJVs after LMA placement had a tendency to become anterior to the CCA when the head of the patient rotated to the opposite direction in infants and children.

The airway device preference may affect the overlapping of the common carotid artery by the internal jugular vein

BACKGROUND

Anatomical variation in the internal jugular vein (IJV), as well as its small size, tendency to collapse, and proximity to the common carotid artery (CCA) makes central venous cannulation via the IJV a technically challenging procedure, especially in pediatric patients.

AIM

We evaluated the effects of laryngeal mask airway insertion and endotracheal intubation (ETT) on the anatomical relationship between the IJV and the CCA in neutral and 40° head away positions.

METHOD

After parental consent 92 patients with ASA physical status I-II, aged 0-17, undergoing elective urological surgery were enrolled and divided into two groups according to the airway management device used for anesthesia: Group laryngeal mask airway (n = 63) and Group ETT (n = 29). An ultrasonographic evaluation was performed before and after airway instrumentation at neutral and 40° head rotation. The IJV position in relation to the CCA was noted, and the overlap percentage of the CCA was calculated as the ratio of the CCA length covering by the internal jugular vein to the transverse diameter of the CCA.

RESULTS

With no airway device insertion, the position of the IJV was found to be anterolateral to the CCA in the majority of patients (48.8% vs 35.3%, right vs left IJV) in the neutral head position. While there was no significant change in the overlap percentages of the CCA after laryngeal mask airway insertion in the neutral head position [48.71% vs 57.30% for the right IJV (difference in median: -21.20; 95% confidence interval (CI) of difference: -56.92 to 14.52; P = 0.133); 52.54% vs 60.36% for the left IJV (difference in median: -10.3; 95% CI of difference: -41.49 to 20.89; P = 0.128)], it increased significantly in the 40° head away position on both sides [50.11% vs 64.83% for the right IJV (difference in median: -55; 95% CI of difference: -84 to -25.24; P = 0.01); 53.82% vs 71.20% for the left IJV (difference in median: -46; 95% CI of difference: -86.85 to -5.15; P = 0.004)]. However, the overlap percentages of CCA decreased significantly on the right side with patients in a neutral head position (31.23% vs 6.27%, difference in median: 19; 95% CI of difference: -5.68 to 43.68; P = 0.002) and on both sides in the 40° head away position [29.50% vs 16.19%, difference in median: 26; 95% CI of difference: 2.84 to 49.16; P = 0.03 and 47% vs 31.94%, difference in median: 9.50; 95% CI of difference: -40.87 to 59.87; P = 0.03 for the right and left sides, respectively] after ETT insertion.

CONCLUSIONS

Laryngeal mask airway with 40° head rotation increases, whereas ETT decreases, the overlap percentage of CCA by IJV. Both head position and airway management methods have an influence on the overlap of the CCA by the IJV in pediatric patients.

The dynamics of changing internal jugular veins diameter based on increasing head elevation angle

CONTEXT

Venous outflow from the cranial cavity occurs mainly through the internal jugular vein (IJV). The increase in venous outflow through IJV is possible by head elevation. IJV collapse may indicate the reduction of blood volume in the vein and show the head elevation effectiveness.

AIMS

The aim of this study is to examine the impact of head elevation on IJV size.

SUBJECTS AND METHODS

IJV ultrasound scanning in 31 healthy volunteers was carried after gradual head elevation at 15°, 30°, and 45°. Maximum and minimum IJV diameters were recorded. Mean ± standard deviation, median, range, and collapsibility index were calculated.

RESULTS

Thirty-one volunteers were involved (19 males), their average age was 37.0 ± 11.5 years. Increasing the head elevation angle by 15°, 30° and 45° resulted in a decrease in IJV diameter in the right and left sides in all patients. The occurrence of the vein walls collapse corresponds to the collapsibility index equal to 100%. The results showed that 100% collapsibility index was recorded in 6 patients (19%) at 15° head elevation, in 12 patients (39%) at 30°, in 11 patients (35%) at 45°. In two volunteers (6%), 100% collapsibility index was not recorded even at maximum 45° head elevation.

CONCLUSIONS

Ultrasound IJV scanning during gradual head elevation together with the collapsibility index calculation could be useful guidance for the venous outflow assessment. In order to prove and extend the study findings, more research is needed.

The Year in Review

Congenital cardiac anesthesiology is a young and rapidly growing subspecialty. It embraces a large spectrum of congenital and acquired heart diseases, which now affect the entire life span of patients from “cradle to grave.” One of the challenges faced by congenital cardiac anesthesiologists is reading the large amount of relevant literature from the fields of cardiology, cardiac surgery, intensive care medicine, and anesthesiology. This review highlights some of the current themes in the literature during the past year.