Modeling Blood Flow in Veins of Uniform Properties (Giraffe Jugular Vein)

This paper models the giraffe’s jugular veins as a uniform collapsible tube from a rigid skull. The equations governing one-dimensional steady flow through such a tube for various conditions have been developed. The effects of inertial and inclination angles that have not been discussed previously have been included. It has been shown that different flows for a uniform tube (vein) are possible. However, this flow matches that of a jugular vein which is supercritical, and the steady solution has been given by the balance between the driving forces of gravity and the viscous resistance to the flow at the right atrium of the heart must be sub-critical for a fixed right-atrium pressure which means that an elastic jump is required to return the flow to sub-critical from the supercritical flow upstream this type of relationship gives rise to flow limitation at the same time given any right atrium fixed pressure there exists a maximum flow rate which when exceeded the boundary conditions of the flow do not hold boundary conditions at the right atrium are not satisfied hence making the steady flow impossible this mechanism of flow limitation is slightly different from the other one in that causes airways through forced expiration from the observation made it is clearly shown that there is an intravascular pressure difference with a change in height.

Seeing beneath the surface:Harnessing point-of-care ultrasound for internal jugular vein evaluation

Point-of-care ultrasound(POCUS)of the internal jugular vein(IJV)offers a noninvasive means of estimating right atrial pressure(RAP),especially in cases where the inferior vena cava is inaccessible or unreliable due to conditions such as liver disease or abdominal surgery.While many clinicians are familiar with visually assessing jugular venous pressure through the internal jugular vein,this method lacks sensitivity.The utilization of POCUS significantly enhances the visualization of the vein,leading to a more accurate identification.It has been demonstrated that combining IJV POCUS with physical examination enhances the specificity of RAP estimation.This review aims to provide a comprehensive summary of the various sonographic techniques available for estimating RAP from the internal jugular vein,drawing upon existing data.

Application of the “Three Threes” Method in Clinical Teaching of Internal Jugular Vein Puncture

Objective: To clarify the role of the “Three Threes” method in clinical teaching of internal jugular vein puncture and explore improvements in teaching methods. Methods: A doctor was assigned to the induction room of the Second Affiliated Hospital of Naval Medical University (Shanghai Changzheng Hospital) for two months. The time required for catheterization, the first puncture success rate, and occurrence of puncture-related complications were compared before and after learning the “Three Threes” method. Results: Using the “Three Threes” method reduced the catheterization time by 43%, increased the first puncture success rate by 17%, and led to fewer puncture-related complications. Conclusion: The application of the “Three Threes” method not only improves the success rate of internal jugular vein puncture but also reduces complications, making it easier for students to master the technique.

Thoracic duct cannulation during left internal jugular vein cannulation:A case report

BACKGROUND Central venous catheter insertion is an invasive procedure that can cause complications such as infection,embolization due to air or blood clots,pneumothorax,hemothorax,and,rarely,chylothorax due to damage to the thoracic duct.Herein,we report a case of suspected thoracic duct cannulation that occurred during left central venous catheter insertion.Fortunately,the patient was discharged without any adverse events related to thoracic duct cannulation.CASE SUMMARY A 46-year-old female patient presented at our department to undergo cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.During anesthesia,we decided to insert a central venous catheter through the left internal jugular vein because the patient already had a chemoport through the right central vein.During the procedure,blood reflux was observed when the needle tip was not within the ultrasound field of view.We did not try to find the tip;however,a guide wire and a central venous catheter were inserted without any resistance.Subsequently,when inducing blood reflux from the distal port of the central venous catheter,only clear fluid,suspected to be lymphatic fluid,was regurgitated.Further,chest X-ray revealed an appearance similar to that of the path of the thoracic duct.Given that intravenous fluid administration was not started and no abnormal fluid collection was noted on preoperative chest X-ray,we suspected thoracic duct cannulation.CONCLUSION It is important to use ultrasound to confirm the exact position of the needle tip and guide wire path.

Thrombosis of the internal jugular vein,a rare entity:A case report and brief review of the literature

Rationale:Thrombosis of the internal jugular vein is an infrequent and underdiagnosed pathology due to the absence of symptoms.If present,the symptoms are frequently manifested as a sensation of pain and cervical tension.Its etiology is variable,including trauma,central catheterization,and hypercoagulable states,among others.Patient’s Concern:A 41-year-old female,previously healthy,was admitted to the emergency room for worsening pain in the left cervical area of 5 d.Previously,she was treated for suspected acute pharyngotonsillitis yet without improvement.Diagnosis:Physical examination revealed a 2 cm in length cervical mass of hard consistency that was painful on palpation and non-fluctuating.Ultrasound study showed thrombosis of the left internal jugular vein.A computed tomography scan revealed that the thrombosis occurred at the cervical portion of the left internal jugular vein as well as the left transverse sinus.Interventions:Hospital admission and treatment with low molecular weight heparin at a dose of 1.5 mg/kg every 24 h.Outcomes:The patient was discharged after 3 d of treatment with vitamin K antagonists.Lessons:Venous thrombosis at the level of the internal jugular vein is an infrequent entity.Clinical suspicion is necessary for the diagnosis given the possibility of absence of symptoms.

Internal Jugular Vein Graft after Inadvertent Severing of the Internal Carotid Artery during Carotid Endarterectomy and an Urgent Re-Exploration for Immediate Post-Operative Wound Site Bleeding: A Case Report

Carotid endarterectomy is a well-established treatment for preventing stroke in selected patients. Although there is debate over whether patch angioplasty or primary closure should be used to reconstruct the bifurcation after carotid endarterectomy, there is growing evidence in the literature in favor of patch angioplasty. When compared to primary closure, patch angioplasty during conventional carotid endarterectomy is suggested to lower the incidence of restenosis and recurrent ipsilateral stroke. Various materials have been used as a patch in this procedure, including the saphenous vein, synthetic patches, or less frequently, an internal jugular vein patch where extensive narrowing of the internal carotid artery is evident. In our case, we used an internal jugular vein graft after inadvertent severing the internal carotid artery (ICA) during carotid endarterectomy after the failure of reconstruction with a saphenous vein patch. We also encountered immediate postoperative reactionary hemorrhage following anesthetic reversal, necessitating an urgent re-exploration. The purpose of this case report is neither an attempt to suggest all patients need angioplasty nor to state that an internal jugular vein patch or graft is superior to synthetic material or saphenous veins;rather, it is an attempt to emphasize a potentially effective rescue way to reconstruct inadvertent extensive vascular injury during carotid endarterectomy.

Ultrasound based estimate of central venous pressure:Are we any closer?

Central venous pressure(CVP)serves as a direct approximation of right atrial pressure and is influenced by factors like total blood volume,venous compliance,cardiac output,and orthostasis.Normal CVP falls within 8-12 mmHg but varies with volume status and venous compliance.Monitoring and managing disturbances in CVP are vital in patients with circulatory shock or fluid disturbances.Elevated CVP can lead to fluid accumulation in the interstitial space,impairing venous return and reducing cardiac preload.While pulmonary artery catheterization and central venous catheter obtained measurements are considered to be more accurate,they carry risk of complications and their usage has not shown clinical improvement.Ultrasound-based assessment of the internal jugular vein(IJV)offers real-time,non-invasive measurement of static and dynamic parameters for estimating CVP.IJV parameters,including diameter and ratio,has demonstrated good correlation with CVP.Despite significant advancements in non-invasive CVP measurement,a reliable tool is yet to be found.Present methods can offer reasonable guidance in assessing CVP,provided their limitations are acknowledged.

Malignant meningioma with jugular vein invasion and carotid artery extension:A case report and review of the literature

BACKGROUND Grade II and III meningiomas[World Health Organization(WHO)classification]rarely have extracranial metastases via the blood circulation;however,we experienced a case with a metaplastic atypical meningioma and local dedifferentiation that metastasized to the jugular vein,carotid artery and subclavian artery at the cervicothoracic junction.Such cases have seldom been reported before.CASE SUMMARY The patient was a 30-year-old man who developed right neck masses with dysphagia,labored breathing,dizziness,and occasional earaches.Eight months earlier the patient was diagnosed with a right parietal lobe neoplasm and hemorrhage at a local hospital due to the sudden onset of headaches and left limb weakness,and the post-operative pathology was a metaplastic atypical meningioma(WHO grade II)with local de-differentiation(WHO III).Magnetic resonance imaging revealed a calcified mass at the root of the neck on the right and a large cystic mass in the right parapharyngeal space.Head and neck angiography showed that the right common carotid artery was compressed and completely occluded,and the jugular vein was enveloped by the tumor and occluded.A balloon occlusion test showed no perfusion in the right common carotid artery.Tumor resection,carotid artery ligation,and subclavian artery reconstruction were performed.The tumor was a malignant meningioma.Postoperatively,the patient had Horner's syndrome and hoarseness.CONCLUSION This case highlights the importance of the link between a large cervical mass and a primary intracranial tumor.Malignant meningioma should not be considered merely as an intracranial metastasis spread through cerebrospinal fluid,it can also be transferred through the circulation to the parapharyngeal space and the cervical great vessels.

Malignant otitis externa with subsequent internal jugular vein thrombosis and hypoglossal palsy:a report and review of literature

Inflammation of a part or whole of the temporal bone and surrounding soft tissue is termed as malignant otitis externa,which typically spreads to skull base to involve cranial nerves VII.Rarely can it also effect one or more of cranial nerves IX,X,XI,and XII.We present a case of malignant otitis externa which presented with symptomatic palsy of IX and XII nerves sparing the VII cranial nerve.The patient though later on had internal jugular vein thrombosis,which we presume is due to the involvement of the parapharyngeal space that prompted us to reconsider the diagnosis,and later on,to aggravate the therapy.With proper blood sugar control and appropriate long term antibiotics,not only that the patient is disease free at one year follow up,but the cranial nerve deficits also recovered.Apart from sharing the clinical and management details of this patient,we have reviewed the relevant literature in the discussion,which has shed some light onto some of the interesting facts about this condition and its prognosis.

Massive hemothorax following internal jugular vein catheterization under ultrasound guidance:A case report

BACKGROUND Hemothorax is a rare but life-threatening complication of central venous catheterization.Recent reports suggest that ultrasound guidance may reduce complications however,it does not guarantee safety CASE SUMMARY A 75-year-old male patient was admitted for laparoscopic radical nephrectomy.Under ultrasound guidance,right internal jugular vein catheterization was successfully achieved after failure to aspirate blood from the catheter in the first attempt.Sudden hypotension developed after surgical positioning and persisted until the end of the operation,lasting for about 4 h.In the recovery room,a massive hemothorax was identified on chest radiography and computed tomography.The patient recovered following chest tube drainage of 1.6 L blood.CONCLUSION Hemothorax must be suspected when unexplained hemodynamic instability develops after central venous catheterization despite ultrasound guidance.So the proper use of ultrasound is important.

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.

Effect of Head Position Angles on the Blood Flow in the Jugular Vein of Giraffes

The study investigated the effect of the angular position of the head on the blood flow in the jugular vein of giraffes. The vein considered is elastic and collapsible such that its cross-sectional area is not uniform. Transmural pressure causes the blood to move along the vein. Mathematical equations describing the flow were developed, and the vein was considered to be inclined at an angle φ to the horizontal. A finite-difference scheme was used to solve the equations of motion for the flow. The results are presented via relevant tables and plots. Our findings show that a change in the position of the head causes variation in the external pressure, which in turn causes variation in the cross-sectional area of the vein. Moreover, a drop (or increase) in the inertial pressure of the blood may cause the vein to collapse (or distend), which again triggers a change in the pressure.

To improve the mechanical function of bovine jugular vein by external stent

Objective To increase the mechanic characteristic of bovine jugular veins conduit (BJVC) by combined knitted stent outside made of nylon fiber. Methods Got rid of the cells of BJVC by enzymolysis,then combined a fabric stent with a acellular bovine jugular vein

Central venous catheterization-related complications in a cohort of 100 hospitalized patients:An observational study

Objective:To evaluate the complications of central venous catheterization(CVC).Methods:A prospective,observational study was conducted at a tertiary care center in India from December 2018 to September 2020.Critically ill patients(aged≥18 years)in the intensive care unit undergoing CVC procedures were included in the study.Baseline demographics and detailed medical history were recorded.Chest X-rays and electrocardiography were performed on all the patients.Complications associated with CVC were recorded.Results:A total of 100 patients with the indication for central venous catheter insertion were included.The majority(81%)of the patients were inserted with CVC at the right internal jugular vein.Complications such as arterial puncture(2%),hematoma(4%),blood clot formation(4%),catheter kinking(3%),thoracic injury(1%),thrombophlebitis(6%),sepsis(9%)and nerve injury(1%)were reported.Conclusions:Though central venous access is preferred in management of critically ill patients,it has its risks.However,early recognition and prompt management of complications may reduce mortality and morbidity.Physicians and intensive care unit intensivists should be vigilant for central venous catheter-related complications.Suitable site selection,operator experience,and proper catheter maintenance are associated with optimal outcomes.

Impact of central venous port implantation method and access choice on outcomes

BACKGROUND Although the number of patients who need central venous ports for permanent vascular access is increasing,there is still no“gold standard”for the implantation technique.AIM To identify the implantation technique that should be favored.METHODS Two hundred central venous port-implanted patients in a tertiary hospital were retrospectively evaluated.Patients were assigned into two groups according to the access method.The first group comprised patients whose jugular veins were used,and the second group comprised patients whose subclavian veins were used.Groups were evaluated regarding age,sex,application side,primary diagnosis,active follow-up period in the hospital,chemotherapy agents administered,number of complications,and the Clavien-Dindo severity score.The distribution of the variables was tested with the Kolmogorov-Smirnov test and the Mann-Whitney U test.Theχ^(2) test was used to analyze the variables.RESULTS There was no statistically significant difference between the groups regarding age,sex,side,number of chemotherapy drugs,and duration of port usage(P>0.05).Only 2 patients in group 1 had complications,whereas in group 2 we observed 19 patients with complications(P<0.05).No port occlusion was found in group 1,but the catheters of 4 patients were occluded in group 2.One port was infected in group 1 compared to three infected ports in group 2.Two port ruptures,two pneumothorax,one revision due to a mechanical problem,one tachyarrhythmia during implantation,and four suture line problems were also recorded in group 2 patients.We also showed that it would be sufficient to evaluate and wash ports once every 2 mo.CONCLUSION Our results robustly confirm that the jugular vein route is safer than the subclavian vein approach for central venous port implantation.

Anatomic relationship of the internal jugular vein and the common carotid artery in Chinese people

Background Variations in position and relationship between the internal jugular vein （IJV） and the common carotid artery （CCA） may lead to inadvertent artery puncture which could be disastrous during central venous access. We demonstrated the anatomic relationship of the IJV with CCA in order to find the optimal site and avoid damage of CCA. Methods Two hundred and twenty surgical patients were enrolled. We analyzed the distance and relationship between the IJV and CCA at three cross sections （upper border of the thyroid cartilage, cricoid cartilage and second tracheal ring） by ultrasonography and then measured the diameters of the IJV and CCA and the distances from the IJV and CCA to the skin. Results Twenty patients were excluded on the basis of exclusion criteria. From up to down at bilateral neck, the IJV became gradually more superficial while the CCA became deeper. The diameter of the IJV became gradually larger while that of the CCA gradually smaller. The IJV from lateral to the CCA gradually moved to the front of the CCA, so the percent overlap of the IJV and CCA was gradually increased. Compared with the left side at the same transverse scan level, the distance between the CCA and IJV was wider at the right side and the right IJV was wider. The IJV location in 11 patients was medial to the CCA at one or more transverse scan levels. The angle between the IJV and CCA was significantly small in elderly patients. The CCA had already furcated at the level of the upper border of the thyroid cartilage in seven patients at the right side and in 12 patients at the left side. Conclusions There are variations in the position and relationship between the IJV and CCA. It is relatively more difficult to puncture at the left side of the neck, at a lower position or in elderly patients. On the contrary, it is relatively easier to puncture at the right side, at the level of the cricoid cartilage or in younger patients.

Flexible Subclavian Artery Closure for an Inadvertent Injury to the Internal Mammary Artery During Internal Jugular Vein Catheterization

Central vein catheter （CVC） placement, which is widely utilized in clinical departments, is also highly important in preoperative preparations for radiofrequency catheter ablation （RFCA）. The internal jugular vein or subclavian vein is the routine target. Arterial injury is not uncommon during the procedure but is potentially devastating in spite of the safety and advantages of the Seldinger technique. Compressing of the airway by a hematoma, as well as hemothorax, pseudoaneurysm, arteriovenous fistula, stroke, and even death, has been well-described.

One case of guide wire fracture and retention in child＇s internal jugular vein puncture

Central venous catheterization was a common technology in clinical anesthesia and rescue. Guide wire fracture and retention was a very rare and severe complication in central venous catheterization. Here, we reported a case that guide wire was broken and remained in the body in internal jugular vein puncture process in an 8-year-old boy.

Simultaneous Determination of Pinoresinol Di-gluco-pyranoside and Pinoresinol Glucoside in Rat Plasma by HPLC-tandem MS/MS for Pharmacokinetic Study

Objective Pinoresinol di-glucopyranoside（PDG） is one of the main active lignans of Eucommiae Cortex considered to be a high-quality antihypertensive drug. In this study the pharmacokinetic process of PDG and its primary in vivo metabolite pinoresinol glucoside（PG） in the portal and jugular vein were surveyed and evaluated simultaneously. Methods A sensitive high-performance liquid chromatography coupled with tandem quadruple mass spectrometry（HPLC-MS/MS） method and sample preparation protocol were developed and validated in method of selectivity, sensitivity, precision, stability, and extraction recovery for the simultaneous determination of PDG and its primary metabolite PG in rat plasma. The double intubation technique was used to simultaneously collect blood from common jugular vein and hepatic portal vein after single ig administration of PDG. Results Using this method, the quantification linearity ranges of PDG and PG in rat plasma were both 0.05-100 ng/mL. This method was successfully applied to the evaluation of the absolute oral bioavailability of PDG and determination of the pharmacokinetic properties of PDG and PG after ig administration of single dose in rats. The bioavailability of PDG at common jugular vein was 51.3% compared to that of 91.6% at hepatic portal vein. Conclusion We conclude that liver is the major conversion site of PDG to PG.