Comparison of aortic zones for endovascular bleeding control: age and sex differences

PURPOSE

To gain insight into anatomical variations between sexes and different age groups in intraluminal distances and anatomical landmarks for correct insertion of resuscitative endovascular balloon occlusion of the aorta (REBOA) without fluoroscopic confirmation.

MATERIALS

All non-trauma patients receiving a computed tomography angiography (CT-A) scan of the aorta, iliac bifurcation and common femoral arteries from 2017 to 2019 were eligible for inclusion.

METHODS

Central luminal line distances from the common femoral artery (CFA) to the aortic occlusion zones were measured and diameters of mid zone I, II and III were registered. Anatomical landmarks and correlations were assessed. A simulated REBOA placement was performed using the Joint Trauma System Clinical Practice Guideline (JTSCPG).

RESULTS

In total, 250 patients were included. Central luminal line (CLL) measurements from mid CFA to aortic bifurcation (p = 0.000), CLL measurements from CFA to mid zone I, II and III (p = 0.000) and zone I length (p = 0.000) showed longer lengths in men. The length of zone I and III (p = 0.000), CLL distance measurements from the right CFA to mid zone I (p = 0.000) and II (p = 0.013) and aortic diameters measured at mid zone I, II and III increased in higher age groups (p = 0.000). Using the JTSCPG guideline, successful deployment occurred in 95/250 (38.0%) in zone III and 199/250 (79.6%) in zone I. Correlation between mid-sternum and zone I is 100%. Small volume aortic occlusion balloons (AOB) have poor occlusion rates in zone I (0-2.8%) and III (4.4-34.4%).

CONCLUSIONS

Men and older age groups have longer CLL distances to zone I and III and introduction depths of AOB must be adjusted. The risk of not landing in zone III with standard introduction depths is high and balloon position for zone III REBOA is preferably confirmed using fluoroscopy. Mid-sternum can be used as a landmark in all patient groups for zone I. In older patients, balloon catheters with larger inflation volumes must be considered for aortic occlusion.

Anatomy and external landmarks of the superficial temporal artery using 3-dimensional computed tomography

PURPOSE

The purpose of this study was to analyze the anatomical variability of the superficial temporal artery (STA) and to provide an easy visual landmark to find the STA and its branches to facilitate its surgical access.

METHODS

A retrospective study was conducted on 57 patients who underwent a head and neck computed tomography with contrast injection. A visual landmark running from the tragus to the corner of the eye was used: the "eye-tragus-line" (ETL). On the ETL, the distance between the tragus and the STA was measured. The length of the STA main branch, its parietal and frontal branch and the angle of the STA and its branches with the ETL were measured. The division of the STA was studied as above/at the same level/below the zygomatic arch (ZA) and the ETL.

RESULTS

The STA division was located above the ZA in 61.54% of cases, at the same level in 26.92% of cases and below in 11.54% of cases. Regarding the ETL, 93.27% of the STA divisions were located above the ETL, 5.77% at the same level and 0.96% below. On the ETL, the STA was located 15.55 ± 4.5 mm in front of the tragus.

CONCLUSION

This study allowed to define an easy visual landmark: the ETL running from the tragus to the corner of the eye. The STA main branch was located 15.55 ± 4.5 mm of front of the tragus on the ETL. The STA division was nearly always located above the ETL (99.04%). Furthermore, this study provides a statistical representation of the anatomy of the STA and its branches.

Anatomical landmarks for safely implementing resuscitative balloon occlusion of the aorta (REBOA) in zone 1 without fluoroscopy

Background

Resuscitative balloon occlusion of the aorta (REBOA) can maintain hemodynamic stability during hemorrhagic shock after a following torso injury, although inappropriate balloon placement may induce brain or visceral organ ischemia. External anatomical landmarks [the suprasternal notch (SSN) and xiphoid process (Xi)] are empirically used to implement REBOA in zone 1. We aimed to confirm if these landmarks were useful for determining a balloon catheter length for safe implementation of REBOA in zone 1 without using fluoroscopy.

Method

We selected 25 successive adult blunt trauma cases requiring contrast-enhanced chest/abdominal computed tomography (CT) treated at our emergency department (in an urban area of Kyoto city, Japan) between October 1, 2016 and January 31, 2017. We retrospectively evaluated anonymized CT images. We used three-dimensional multiplanar reconstructions to measure the length along the aorta’s central axis, from the bilateral common femoral arteries (FA) to the celiac trunk (CeT) (FA–CeT) and to the origin of the left subclavian artery (LSCA) (FA–LSCA). Volume-rendering reconstruction images were used to measure the external distance from common FAs to SSN (FA–SSN) and to Xi (FA–Xi).

Result

FA–LSCA was significantly longer than FA–SSN. FA–CeT was significantly shorter than FA–Xi.

Discussion

Based on these results, the REBOA balloon catheter should be shorter than FA–SSN, and longer than FA–Xi to avoid placement outside zone 1. The advantages of this method are that it can rapidly and easily predict a safe balloon catheter length, and it reflects each patient’s individual torso height.

Conclusion

To safely implement REBOA, the balloon catheter length should be shorter than FA–SSN and longer than FA–Xi. We believe that these anatomical landmarks are good references for safe implementation of REBOA in zone 1 without radiographic guidance.

Surface Landmarks do not Correspond to Exact Levels of the Cervical Spine: References According to the Sex, Age and Height

Objective

A general orientation along the cervical spine could be estimated by external landmarks, and it was useful, quick and less exposable to radiation, but, sometimes it gave reference confusion of target cervical level. The authors reviewed the corresponding between the neck external landmarks and cervical levels.

Methods

Totally 1,031 cervical lateral radiographs of different patients were reviewed in single university hospital. Its compositions were 534 of males and 497 females; 86 of second decades (10-19 years-old), 169 of third decades, 159 of fourth decades, 209 of fifth decades, 275 of sixth decades, and 133 of more than seventh decades (>60 years-old). Reference external landmarks (mandible, hyoid bone, thyroid cartilage, and cricothyroid membrane) with compounding factors were reviewed.

Results

The reference levels of cervical landmarks were C2.13 with mandible angle, C3.54 with hyoid bone, C5.12 with thyroid cartilage, and C6.01 with cricothyroid membrane. The reference levels of cervical landmarks were differently observed by sex, age, and somatometric measurement (height) accordingly mandible angle from C1 to C3, hyoid bone from disc level of C2 and C3 to C5, thyroid cartilage from disc level of C3 and C4 to C7, and cricothyroid membrane from C4 to disc level of C7 and T1.

Conclusion

Surface landmarks only provide general reference points, but not correspond to exact levels of the cervical spine. Intraoperative fluoroscopy ensures a more precise placement to the targeted cervical level.

The mid-sternal length, a practical anatomical landmark for optimal positioning of long-term central venous catheters

BACKGROUND

Long-term tunneled catheters are used for the hemodialysis or chemotherapy in many patients. Proper placement of the catheter tip could reduce early and late catheter related complications. Aim of the present study was to evaluate a new formula for proper placement of tunneled hemodialysis or infusion port device by using an external anatomic landmark.

MATERIALS AND METHODS

A total of 64 adult patients undergoing elective placement of tunneled Central Venous Catheter (CVC) requiring hemodialysis or chemotherapy were enrolled in this prospective study during 2011-2012 in the university hospital. The catheter length to be inserted in the right internal jugular vein (IJV) was calculated by adding two measurements (the shortest straight length between the insertion point of the needle and the suprasternal notch plus and half of sternal length). The catheter position was considered correct if the tip was positioned in the right atrium (RA) or Superior vena cava (SVC)-RA junction.

RESULTS

The patients were 55.28 ± 19.85 years of age, weighed 5.78 ± 16.62 kg and were 166.07 ± 10.27 cm tall. Catheters were inserted successfully in 88% of patients (n = 56). Catheter tip positions in the failures were SVC (n = 5), tricuspid valve (n = 2), and right ventricle (n = 1) in our patients.

CONCLUSION

Long-term hemodialysis or port CVC could easily insert in the right IJV by using half of the sternal length as an external land marks among adult patients.