A Modified Surface Measurement Method to Determine Catheter Length of Totally Implantable Venous Access Port Via the Right Internal Jugular Vein

A Modified Surface Measurement Method to Determine Catheter Length of Totally Implantable Venous Access Port Via the Right Internal Jugular Vein | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article A Modified Surface Measurement Method to Determine Catheter Length of Totally Implantable Venous Access Port Via the Right Internal Jugular Vein Hao Zou, Mengting Chen, Guanguan Luo, Jun Shen, Weijun Fang This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6512487/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background The accurate determination of the optimal length of catheters for Totally Implantable Venous Access Ports (TIVAP) is crucial to prevent complications and improve patient care. This study sought to evaluate the reliability of a modified surface measurement method for determining the ideal tip position of TIVAP catheters inserted via the right internal jugular vein. Methods A retrospective study was conducted, involving a total of 211 patients diagnosed with malignant neoplasms, who underwent TIVAP implantation. A modified surface measurement method was employed to accurately determine the appropriate catheter length for TIVAP placement. This involved measuring the distance from the puncture point (Point A) to the right clavicular notch (Point B), denoted as AB, as well as the distance from the puncture point (Point A) to the portal body (Point C), denoted as AC. The catheter length was then calculated using the equation: catheter length (cm) = AB + AC + 7. The position of the catheter tip was assessed through the use of chest radiography (CXR). Results The mean length of the catheter implanted in all patients was 21.29 ± 1.25 cm (male vs. female, 21.46 ± 1.20 cm vs. 20.99 ± 1.29 cm; p < 0.05). The optimal positioning rate, determined by the vertebral body unit (VBU) measurement, was found to be 94.31%. Additionally, the optimal placement rate based on direct measurement was 92.42%. There were weak but statistically significant associations between the catheter length and the height and weight of patients. Conclusions A revised method for measuring the catheter length of TIVAP via the right internal jugular vein has been developed using surface measurements. This method has been proven to be highly reliable in locating the optimum tip position and was verified by CXR. Totally implantable venous access port Right internal jugular vein Surface measurement Catheter length Figures Figure 1 Figure 2 Figure 3 Figure 4 1 Introduction The totally implantable venous access port (TIVAP) functions as a fully implantable drug delivery system, positioned subcutaneously, notably appropriate for those requiring protracted (over three months) infusion of chemotherapy drugs, parenteral nutrient solutions, and blood products. 1 It improves patients' quality of life, and facilitates the convenient administration of drug treatments while significantly reducing the risk of infection and embolism. 2 Compared to peripherally inserted central catheters (PICC), TIVAP presents a better safety profile, with lower incidence rates of adverse effects, especially regarding catheter-related thrombosis and allergic reactions. 3 The performance of TIVAP is closely linked to the positioning of the catheter tip. If the tip position is suboptimal, there is an increased risk of catheter-related complications such as catheter dysfunction, arrhythmias, venous thrombosis, hydrothorax and cardiac tamponad. 4 – 6 Various methods are utilized to evaluate the most suitable catheter length and ensure optimal tip positioning, encompassing fluoroscopy-guided, intracardiac electrocardiography (IECG)-guided, and measurements via surface landmarks. 7 The surface measurement method stands out amongst these methods as the most effective and convenient means. It is widely used and recommended by the Oncology Nursing Society (ONS) in their guidelines for vascular access. As per the ONS guideline, the length of the catheter is determined by adding the distances from the puncture site to the right sternoclavicular joint and then to the third rib. 8 Based on the ONS method, we have developed a modified method that utilizes the clavicular notch to predict catheter length for TIVAP through the right internal jugular vein. Post-procedural chest radiography (CXR) should be conducted to assess the position of the catheter tip. 7 , 9 , 10 In this study, our primary objective is to evaluate the dependability of our modified surface measurement method in determining the optimal position of the TIVAP catheter tip through post-procedural CXR. 2 Method 2.1 Study Participants This retrospective analysis reviewed patients with malignant neoplasms who received ultrasound-guided TIVAP implantation through the right internal jugular vein at the emergency department of Zhongnan Hospital of Wuhan University between July 2017 and December 2019. Ethical approval for this study was granted by the Institutional Ethics Committee of Zhongnan Hospital of Wuhan University (ethical approval number: 2023063k). All procedures performed in this study involving human participants were conducted in accordance with the ethical standards of the institutional and/or national research committee, and adhered to the 1964 Declaration of Helsinki and its subsequent amendments, or comparable ethical standards. The final analysis included 211 cases, after applying the following inclusion criteria: 1. Patients diagnosed with malignant neoplasms (including those with recurrence and metastasis); 2. In need of chemotherapy; 3. Patients and their families consented to TIVAP implantation; 4. Patients were in good general health and able to tolerate TIVAP implantation. The exclusion criteria encompassed the following: 1. Inability to tolerate or cooperate with the surgical procedure; 2. Obvious coagulation dysfunction; 3. Allergic reactions to materials; 4. Existing thrombosis, stenosis, or other implants affecting the vascular access; 5. Abnormal venous return, such as vena cava compression syndrome; 6. Uncontrolled bacteremia or local infection at the operation site; 7. Patients who had previously undergone radiotherapy at the intended puncture site. 2.2 Data collection The clinical data for this study were obtained by reviewing electronic medical records. These records contained essential patient information such as age, gender, height, weight, diagnosis, TIVAP implantation site, catheter length and imaging information. 2.3 Implantation procedures Before port implantation, written informed consent was obtained from each patient. A PORT-A-CATH system (Smiths Medical, Germany) was used in the study. The procedure was performed by experienced attending physicians, Dr Shen and Dr Fang, in an operating room under strict sterile conditions. We utilized ultrasound to locate the internal jugular vein and mark the puncture site. The needle was placed obliquely towards the ipsilateral nipple within a triangular region formed by the lower end of the sternocleidomastoid muscle and the clavicle. This specific anatomical location, approximately 2 cm above the clavicle, served as a fixed reference point. A guide wire was passed through the needle into the superior vena cava. A peel-away sheath was then passed along the guide wire and the catheter was inserted through the sheath. Once the catheter was in place, an incision was made approximately 2–3 cm below the clavicle. Blunt dissection was performed to reach the subcutaneous tissue. The catheter was then pulled through the subcutaneous tunnel from the puncture site to the port pocket. The catheter was trimmed to the length determined by the modified surface measurement method and connected to the portal body. After the procedure, a CXR was performed to verify the position of the catheter tip. 2.4 Modified surface measurement method Our surface measurement method was modified according to the catheter length prediction method recommended by the ONS in Guidelines for Vascular Access: Nursing Practice and Education in 2011. 8 Before catheter insertion, we meticulously measured the distance from the puncture point (Point A) to the right clavicular notch (Point B), denoted as AB. We also measured the distance from the puncture point (Point A) to the portal body (Point C) as AC (Fig. 1 . A). The equation for determining the catheter length has been expressed as catheter length (cm) = AB + AC + 7. 2.5 Imaging evaluation After the operation, the position of the catheter tip was assessed by CXR. CXR was used to measure the length from the carina to the caval-atrial junction (CAJ), the carina to the catheter tip, and the vertebral body unit (VBU). A VBU represents the space between adjacent vertebral bodies, inclusive of the intervertebral disk space, and is measured from the lower endplate of the vertebra, corresponding to the carina's level, down to the lower vertebra's lower endplate. 11 The distance from the carina to the catheter tip is divided by the VBU length. The location of CAJ was defined at the level corresponding to the plane two VBUs below the carina. 12 As for the carina, its location was defined at the level corresponding to the plane intersecting the bronchial bifurcation (Fig. 1 . B). In both adults and children, the catheter tip is considered optimally positioned in the lower third of the SVC, near or at the CAJ. 7 On CXR, the catheter tip located within 2 VBUs or 40 mm below the carina was identified as the optimal position. 13 , 14 The optimal position rate was calculated based on these defined criteria. 2.6 Statistical analysis Frequency (percentages) were used to present categorical variables whereas continuous variables were presented as mean ± standard deviation (SD). Quantitative data was analyzed using independent samples t-tests. Pearson’s correlation analysis was used to analyze the correlation between demographic information, measured lengths and imaging measurement results. The statistical significance was set at p < 0.05. The statistical analyses were performed using version 29.0 of the SPSS software (IBM Corp, Armonk, NY). The graphical representations in this study were created using the R programming language. Various packages were employed, such as the GGally, rstatix, and ggplot2 packages. 3 Results 3.1 Clinical characteristics of patients During the study period, 263 patients met the inclusion criteria, of whom 211 were included in the final analysis dataset after the exclusion of 52 patients (Fig. 2 ). Table 1 shows patients' clinical characteristics. Among the patients, there were 133 male patients (63.0%) and 78 female patients (37.0%). The median age of all patients at the examination was 62 years (range, 13–80 years). The average height was 166.25 ± 6.50 cm, the average weight was 62.76 ± 9.57 kg, and the average body mass index (BMI) was 22.68 ± 3.07 kg/m 2 . Male patients had an average height and weight higher than that of female patients, but there was no statistically significant difference in BMI. The average catheter length for all patients was 21.29 ± 1.25 cm, with a longer length observed in male patients compared to female patients (21.46 ± 1.20 cm vs. 20.99 ± 1.29 cm; p < 0.05). The mean length of AB was also longer in male patients than in female patients (4.63 ± 0.98 cm vs. 4.26 ± 0.97 cm; p < 0.05). Furthermore, the mean length of VBU was longer in male patients than in female patients (25.80 ± 3.18 mm vs. 24.61 ± 2.61 mm; p < 0.05). However, there were no statistically significant statistical variations in the length of AC, the distance from the carina to the tip, the distance from the carina to the CAJ, and the distance from the carina to the tip measured by the VBU between male and female patients. Table 1 Clinical characteristics of patients Characteristics All (N = 211) Male (n = 133) Female (n = 78) P value Age, years 62 (13–80) 65 (13–80) 57 (19–78) Height, cm 166.25 ± 6.50 168.79 ± 5.73 161.91 ± 5.37 < .001 Weight, kg 62.76 ± 9.57 64.31 ± 9.86 60.12 ± 8.47 .002 BMI, kg/m² 22.68 ± 3.07 22.54 ± 3.13 22.93 ± 2.95 .378 Length of catheter, cm 21.29 ± 1.25 21.46 ± 1.20 20.99 ± 1.29 .008 AB, cm 4.49 ± 0.99 4.63 ± 0.98 4.26 ± 0.97 .008 AC, cm 9.81 ± 1.16 9.86 ± 1.08 9.74 ± 1.29 .470 VBU, mm 25.36 ± 3.04 25.80 ± 3.18 24.61 ± 2.61 .004 Carina-tip, mm 18.76 ± 10.50 18.45 ± 10.82 19.29 ± 9.97 .576 Carina-CAJ, mm 41.31 ± 6.29 41.21 ± 6.16 41.48 ± 6.56 .771 Carina-tip/VBU 0.74 ± 0.41 0.72 ± 0.41 0.78 ± 0.40 .299 BMI, body mass index; AB, the distance from the puncture point (Point A) to the right clavicular notch (Point B); AC, the distance from the puncture point (Point A) to the port (Point C); VBU, vertebral body unit; CAJ, caval-atrial junction. Values are reported as median (range) or mean ± standard deviation. 3.2 Imaging measurement on CXR The CXR images showed that the mean distance between the carina and the catheter tip, as measured by the VBU, was 0.74 ± 0.41 VUBs (95% CI -0.06–1.55; Fig. 3 . A). The VBU measurement also revealed an optimal positioning rate of 94.31% (199/211). Meanwhile, direct measurements in length showed that the mean distance from the carina to the catheter tip was 18.76 ± 10.50 mm (95% CI -1.81–39.33; Fig. 3 . B). The optimal positioning rate based on direct measurements was 92.42% (195/211). 3.3 Characteristics related to catheter length In the multivariate correlation analysis, as depicted in Fig. 4 , weak but statistically significant associations between catheter length and various factors were observed. Specifically, there were weak but significant associations between catheter length and height (r = 0.325, p < 0.001), weight (r = 0.276, p < 0.001), VBU (r = 0.232, p < 0.001), and the distance from the carina to the CAJ (r = 0.167, p < 0.05). The study revealed that there are comparable connections between the length of catheter AC and height (r = 0.185, p < 0.01), weight (r = 0.235, p < 0.001), BMI (r = 0.164, p < 0.05), and VBU (r = 0.171, p < 0.05). Additionally, a minor yet substantial correlation was observed between the length of catheter AB and height (r = 0.206, p < 0.01). Conclusively, these results suggest that the height and weight of patients do have a certain impact on the length of catheters. No significant correlations were found between the distance from the carina to the CAJ and variables such as age, height, weight, or BMI. As a result, we can infer that there is no link between the distance from the carina to the CAJ and factors such as age, height, weight, or sex. 4 Discussion This retrospective study aimed to evaluate the reliability of a modified surface measurement method for determining the optimal catheter length of TIVAP catheters implanted via the right internal jugular vein in a cohort of 211 patients. The results demonstrate that this measurement method for catheter length contributed to a high rate of optimal catheter tip placement, as confirmed by CXR. This demonstrates the method's reliability and its applicability in clinical practice. The optimal location of the catheter tip is still controversial. The American Society for Intravenous Infusion Nursing (INS) recommends placing the central venous catheter tip in the lower third of the SVC, at or near the CAJ, to optimize positioning. 7 The European Society for Medical Oncology (ESMO) guidelines advocate placing the central venous catheter tip at the CAJ. 2 While the European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines suggest that the ideal catheter tip location includes the inferior 1/3 part of the SVC, the CAJ, and the upper region of the right atrium within 2cm below the CAJ. 15 A retrospective study reported by Caers et al in 437 patients found that placing the catheter tip in the inferior 1/3 of the SVC resulted in the lowest incidence of thrombosis and catheter dysfunction. 16 Some prior reports have warned against placing the catheter tip inside the heart, as it may result in serious complications. 17 – 19 In 1989, the US Food and Drug Administration required that the central venous catheter tip should be avoided from being placed or displaced inside the heart. 20 While some studies have reported that locating the catheter tip low in the SVC or the right atrium enhances catheter performance and blood flow. 21 , 22 Therefore, there remains a debate about whether the upper right atrium can be considered an ideal catheter tip location. To prioritize patient safety, we have chosen the lower third of the SVC at or near the CAJ as the preferred catheter tip position. Surface measurements, which involve assessing distances between specific anatomical landmarks, are frequently used to determine the appropriate catheter length for both PICC and TIVAP placement. Nevertheless, no universally recognized and accurate method of surface measurement currently exists. The surface measurement method for catheter length determination, as recommended by ONS, is widely used but can be influenced by factors such as obesity. 8 Previous studies have shown that catheter lengths determined by this surface measurement method tend to be longer than those determined by intracardiac electrocardiogram measurement and are associated with a higher incidence of complications. 23 , 24 To address these concerns, we have modified the surface measurement method based on our clinical experience. Previous studies have demonstrated that using the internal jugular vein route may be associated with a lower risk of mechanical complications compared to the subclavian route. 25 The SVC originates from the convergence of the left and right brachiocephalic veins, with a length of approximately 7 cm. Its starting point is posterior to the first right costal cartilage and the sternum. Given that the right clavicular notch is adjacent to the upper edge of the first right costal cartilage, an additional 7 cm below the right clavicular notch ensures that the catheter tip is positioned in the lower third of the SVC, close to the CAJ, without extending too deeply into the right atrium. And clavicular notch is easily identified by palpation. 26 CXR serves as the primary method for verifying the position of the catheter tip following TIVAP implantation. To establish the CAJ as a sound reference point, it necessitates consistent and repeatable identification of anatomical landmarks on the CXR. Various radiographic landmarks are employed for this purpose, including ribs, vertebral bodies, the right bronchus, cardiac silhouette, and the carina. Among these, the carina has consistently proven to be a reliable landmark for confirming the catheter tip's placement. In all cases, the pericardial sac terminates below the level of the carina. And the carina is readily noticeable, even in lower-quality chest X-ray images. 6 , 27 – 31 Furthermore, the VBU is employed as a quantification unit on CXR. Song et al. measured the distance from the carina to the CAJ in adult patients between 40–88 years old using CXR and found it to be 2.4 VBUs. 11 However, their study did not include adolescent or young adult populations. Baskin et al. carried out research on 100 young patients aged 12–28 years, which suggests that the position of the CAJ can be estimated as 2 VBUs below the carin. 32 Similarly, Johnston et al. arrived at a similar conclusion when studying 499 older adults. 12 Wright et al. proposed a "final tip position window" bordering 2 VBUs below the carina on CXR. 33 In 2023, the Consensus of Central Venous Access Working Group, part of the Chinese Association of Integrative Medicine Peripheral Vascular Disease Committee, recommended the anatomical reference location for the CAJ to be 2 VBUs below the carina. 13 Our study has identified the catheter tip's optimal position as being within 2 VBUs below the carina. Based on this criterion, the majority of participants in our study achieved the optimal position. Additionally, several earlier investigations have consistently found that the distance between the carina and CAJ is approximately 40mm across all age ranges. Notely, this distance displayed no correlation with height, weight, body surface area, or gender. 34 – 37 We also observed no significant associations between the distance from the carina to the CAJ and factors such as sex, age, height, and weight. The consensus of Shanghai experts in 2015 proposed that the catheter should be positioned under the carina at an average distance of 40.3 ± 13.6 mm on CXR. 14 By referring to this recommendation, 92.42% of patients in our study achieved the optimal position, further demonstrating the reliability of our modified surface measurement method. Many researchers advocate using the VBU as a ruler to determine the position of the catheter tip. The spine, which is minimally affected by geometric magnification and adaptable to somatic growth, plays a significant role in ensuring accurate catheter placement and measurements. 11 , 32 We recognize the rationale in this viewpoint, thus we endorse the results measured by VBU as a preferred reference. There are certain limitations associated with CXRs, including the potential for subjectivity in interpreting tip positions, 38 and the dynamic movement of the catheter tip due to factors such as patient positioning, respiration, and arm movements. 39 – 41 These factors can result in measurement discrepancies among different patients. To address these issues and improve result accuracy, various measures were implemented. Specifically, we contracted several experienced radiologists to interpret the chest X-rays. Furthermore, we standardized the patients’ position during the radiographic procedures. Additionally, our multivariate correlation analysis revealed weak but statistically significant correlations between catheter length and patient height and weight. In 1990, Peres developed formulas based on patient height to predict the optimal catheter length of catheters. 42 We also attempted to utilize patient height and weight to estimate catheter length. However, despite applying multiple linear regression analysis, the model demonstrated limited fitting and applicability, suggesting the need for further exploration and adjustment with a larger sample size. 5 Conclusion In conclusion, we have designed and validated a modified surface measurement method for determining the catheter length of the TIVAP inserted via the right internal jugular vein. This method demonstrated a high degree of reliability in locating the optimal tip position and was validated by CXR. Declaration of conflicting interests The Authors declare that there is no conflict of interest. Consent to Publish declaration Not Applicable. Consent to Participate declaration Not Applicable. Declarations Declaration of conflicting interests The Authors declare that there is no conflict of interest. Consent to Publish declaration Not Applicable. Consent to Participate declaration Not Applicable. Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. Ethical approval Ethical approval for this study was granted by the Institutional Ethics Committee of Zhongnan Hospital of Wuhan University (ethical approval number: 2023063k). Contributorship Research Conception and Design: Weijun Fang, Mengting Chen and Hao Zou; Data collection: Weijun Fang, Hao Zou and Guanguan Luo; Data Analysis and Interpretation: Mengting Chen and Jun Shen; Writing the Manuscript: Mengting Chen; Critical Revision: Weijun Fang, Hao Zou and Jun Shen. Acknowledgements We would like to thank the emergency department physicians and radiologists at Zhongnan Hospital of Wuhan University for their contributions to this research. References Zhang K-C, Chen L. Chinese expert consensus and practice guideline of totally implantable access port for digestive tract carcinomas. WJG 2020; 26: 3517–3527. Sousa B, Furlanetto J, Hutka M, et al. 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Variables decreasing tip movement of peripherally inserted central catheters in pediatric patients. Pediatr Radiol 2016; 46: 1532–1538. Connolly B, Amaral J, Walsh S, et al. Influence of arm movement on central tip location of peripherally inserted central catheters (PICCs). Pediatr Radiol 2006; 36: 845–850. Peres PW. Positioning Central Venous Catheters – A Prospective Survey. Anaesth Intensive Care 1990; 18: 536–539. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6512487","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":464618819,"identity":"d58e3d4e-29e9-4425-a15c-97333a6a2bd1","order_by":0,"name":"Hao Zou","email":"","orcid":"","institution":"Zhongnan Hospital of Wuhan University","correspondingAuthor":false,"prefix":"","firstName":"Hao","middleName":"","lastName":"Zou","suffix":""},{"id":464618820,"identity":"c5a7d12c-d244-4be5-aefd-512b6a1313e7","order_by":1,"name":"Mengting Chen","email":"","orcid":"","institution":"Zhongnan Hospital of Wuhan University","correspondingAuthor":false,"prefix":"","firstName":"Mengting","middleName":"","lastName":"Chen","suffix":""},{"id":464618821,"identity":"5bcdef9f-a05a-4ae0-8b01-c56e9283ed82","order_by":2,"name":"Guanguan Luo","email":"","orcid":"","institution":"Zhongnan Hospital of Wuhan University","correspondingAuthor":false,"prefix":"","firstName":"Guanguan","middleName":"","lastName":"Luo","suffix":""},{"id":464618822,"identity":"5aad011e-4bc2-4854-ad23-ea07410ab7b9","order_by":3,"name":"Jun Shen","email":"","orcid":"","institution":"Zhongnan Hospital of Wuhan University","correspondingAuthor":false,"prefix":"","firstName":"Jun","middleName":"","lastName":"Shen","suffix":""},{"id":464618823,"identity":"a3ac6ef8-b9c8-40b9-92ea-308ee5d81f27","order_by":4,"name":"Weijun Fang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAx0lEQVRIiWNgGAWjYBAC9gYQyWPDYACmidHCcwBMppGsheEwKVrYzx5+zSNzPnG7RALjg7dtDPLmBLXw5KVZ8/DcTtw5I4HZcG4bg+HOBgJa7BlyzIxzeG7nbriRwCbN28aQYHCAkC38b0BazoG0sP8mTotEjvHjHJ4DYFuYidTyxoz5D09y/YYzD5sl55yTMNxA2GE5xh9n9tgZGxxPPvjhTZmNPEFbgIBNgrEHRDM2AAkJwuqBgPkDww+iFI6CUTAKRsFIBQBQGT5DT7B9lQAAAABJRU5ErkJggg==","orcid":"","institution":"Zhongnan Hospital of Wuhan University","correspondingAuthor":true,"prefix":"","firstName":"Weijun","middleName":"","lastName":"Fang","suffix":""}],"badges":[],"createdAt":"2025-04-23 12:08:46","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6512487/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6512487/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":83836805,"identity":"6ad7923a-0213-4ad6-83e5-b41daa0dc0c1","added_by":"auto","created_at":"2025-06-03 13:20:45","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":291553,"visible":true,"origin":"","legend":"\u003cp\u003eModified surface measurement method and imaging evaluation. (\u003cstrong\u003eA) \u003c/strong\u003eMeasure points of modified surface measurement method. Point A, Puncture point; Point B, The right clavicular notch; Point C, The portal body. (\u003cstrong\u003eB)\u003c/strong\u003e Post-procedural chest radiography (CXR) of a male patient. The relative position of the trachea, carina, and catheter tip are labeled. The vertebral body unit (VBU) is indicated.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6512487/v1/7e6d1b17594a3a3d3160f9da.png"},{"id":83836803,"identity":"102e41ad-2ab8-4f8c-a1a9-5d2cc3cc512d","added_by":"auto","created_at":"2025-06-03 13:20:45","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":76940,"visible":true,"origin":"","legend":"\u003cp\u003eFlow diagram illustrating the enrolment process.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6512487/v1/7a1119f4c927605a41cd9a92.png"},{"id":83837957,"identity":"2e08c3ae-7669-4194-a551-d76580ce84d9","added_by":"auto","created_at":"2025-06-03 13:28:45","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":196092,"visible":true,"origin":"","legend":"\u003cp\u003ePosition of catheter tips on chest radiography (CXR).\u003cstrong\u003e (A)\u003c/strong\u003e Distance from carina to catheter tips in the vertebral body unit (VBU) on CXR. (\u003cstrong\u003eB) \u003c/strong\u003eDistance from catheter tips to the caval-atrial junction (CAJ) on CXR.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-6512487/v1/784cfaff9597f3cf69286af2.png"},{"id":83836808,"identity":"4eb816b1-a396-49dc-b5f0-01e9b72bbf82","added_by":"auto","created_at":"2025-06-03 13:20:45","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":723291,"visible":true,"origin":"","legend":"\u003cp\u003eMatrix diagram of multivariable correlation analysis between clinical characteristics and imaging measurement results.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-6512487/v1/498ae097f5a70922e5f1250c.png"},{"id":85690471,"identity":"9998d234-aff6-47ab-8b72-dea4ca1ee3f2","added_by":"auto","created_at":"2025-06-30 16:46:48","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1808144,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6512487/v1/3978db92-6a02-479c-bb7f-dfd7d20cbdba.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"A Modified Surface Measurement Method to Determine Catheter Length of Totally Implantable Venous Access Port Via the Right Internal Jugular Vein","fulltext":[{"header":"1 Introduction","content":"\u003cp\u003eThe totally implantable venous access port (TIVAP) functions as a fully implantable drug delivery system, positioned subcutaneously, notably appropriate for those requiring protracted (over three months) infusion of chemotherapy drugs, parenteral nutrient solutions, and blood products.\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e It improves patients' quality of life, and facilitates the convenient administration of drug treatments while significantly reducing the risk of infection and embolism.\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e Compared to peripherally inserted central catheters (PICC), TIVAP presents a better safety profile, with lower incidence rates of adverse effects, especially regarding catheter-related thrombosis and allergic reactions.\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eThe performance of TIVAP is closely linked to the positioning of the catheter tip. If the tip position is suboptimal, there is an increased risk of catheter-related complications such as catheter dysfunction, arrhythmias, venous thrombosis, hydrothorax and cardiac tamponad.\u003csup\u003e\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e Various methods are utilized to evaluate the most suitable catheter length and ensure optimal tip positioning, encompassing fluoroscopy-guided, intracardiac electrocardiography (IECG)-guided, and measurements via surface landmarks.\u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eThe surface measurement method stands out amongst these methods as the most effective and convenient means. It is widely used and recommended by the Oncology Nursing Society (ONS) in their guidelines for vascular access. As per the ONS guideline, the length of the catheter is determined by adding the distances from the puncture site to the right sternoclavicular joint and then to the third rib.\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e Based on the ONS method, we have developed a modified method that utilizes the clavicular notch to predict catheter length for TIVAP through the right internal jugular vein. Post-procedural chest radiography (CXR) should be conducted to assess the position of the catheter tip.\u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e,\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e,\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e In this study, our primary objective is to evaluate the dependability of our modified surface measurement method in determining the optimal position of the TIVAP catheter tip through post-procedural CXR.\u003c/p\u003e"},{"header":"2 Method","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1 Study Participants\u003c/h2\u003e \u003cp\u003e This retrospective analysis reviewed patients with malignant neoplasms who received ultrasound-guided TIVAP implantation through the right internal jugular vein at the emergency department of Zhongnan Hospital of Wuhan University between July 2017 and December 2019. Ethical approval for this study was granted by the Institutional Ethics Committee of Zhongnan Hospital of Wuhan University (ethical approval number: 2023063k). All procedures performed in this study involving human participants were conducted in accordance with the ethical standards of the institutional and/or national research committee, and adhered to the 1964 Declaration of Helsinki and its subsequent amendments, or comparable ethical standards. The final analysis included 211 cases, after applying the following inclusion criteria: 1. Patients diagnosed with malignant neoplasms (including those with recurrence and metastasis); 2. In need of chemotherapy; 3. Patients and their families consented to TIVAP implantation; 4. Patients were in good general health and able to tolerate TIVAP implantation. The exclusion criteria encompassed the following: 1. Inability to tolerate or cooperate with the surgical procedure; 2. Obvious coagulation dysfunction; 3. Allergic reactions to materials; 4. Existing thrombosis, stenosis, or other implants affecting the vascular access; 5. Abnormal venous return, such as vena cava compression syndrome; 6. Uncontrolled bacteremia or local infection at the operation site; 7. Patients who had previously undergone radiotherapy at the intended puncture site.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2 Data collection\u003c/h2\u003e \u003cp\u003eThe clinical data for this study were obtained by reviewing electronic medical records. These records contained essential patient information such as age, gender, height, weight, diagnosis, TIVAP implantation site, catheter length and imaging information.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3 Implantation procedures\u003c/h2\u003e \u003cp\u003eBefore port implantation, written informed consent was obtained from each patient. A PORT-A-CATH system (Smiths Medical, Germany) was used in the study. The procedure was performed by experienced attending physicians, Dr Shen and Dr Fang, in an operating room under strict sterile conditions. We utilized ultrasound to locate the internal jugular vein and mark the puncture site. The needle was placed obliquely towards the ipsilateral nipple within a triangular region formed by the lower end of the sternocleidomastoid muscle and the clavicle. This specific anatomical location, approximately 2 cm above the clavicle, served as a fixed reference point. A guide wire was passed through the needle into the superior vena cava. A peel-away sheath was then passed along the guide wire and the catheter was inserted through the sheath. Once the catheter was in place, an incision was made approximately 2\u0026ndash;3 cm below the clavicle. Blunt dissection was performed to reach the subcutaneous tissue. The catheter was then pulled through the subcutaneous tunnel from the puncture site to the port pocket. The catheter was trimmed to the length determined by the modified surface measurement method and connected to the portal body. After the procedure, a CXR was performed to verify the position of the catheter tip.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.4 Modified surface measurement method\u003c/h2\u003e \u003cp\u003eOur surface measurement method was modified according to the catheter length prediction method recommended by the ONS in Guidelines for Vascular Access: Nursing Practice and Education in 2011.\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e Before catheter insertion, we meticulously measured the distance from the puncture point (Point A) to the right clavicular notch (Point B), denoted as AB. We also measured the distance from the puncture point (Point A) to the portal body (Point C) as AC (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. A). The equation for determining the catheter length has been expressed as catheter length (cm)\u0026thinsp;=\u0026thinsp;AB\u0026thinsp;+\u0026thinsp;AC\u0026thinsp;+\u0026thinsp;7.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e2.5 Imaging evaluation\u003c/h2\u003e \u003cp\u003eAfter the operation, the position of the catheter tip was assessed by CXR. CXR was used to measure the length from the carina to the caval-atrial junction (CAJ), the carina to the catheter tip, and the vertebral body unit (VBU). A VBU represents the space between adjacent vertebral bodies, inclusive of the intervertebral disk space, and is measured from the lower endplate of the vertebra, corresponding to the carina's level, down to the lower vertebra's lower endplate.\u003csup\u003e\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e The distance from the carina to the catheter tip is divided by the VBU length. The location of CAJ was defined at the level corresponding to the plane two VBUs below the carina.\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e As for the carina, its location was defined at the level corresponding to the plane intersecting the bronchial bifurcation (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. B). In both adults and children, the catheter tip is considered optimally positioned in the lower third of the SVC, near or at the CAJ.\u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e On CXR, the catheter tip located within 2 VBUs or 40 mm below the carina was identified as the optimal position.\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e,\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e The optimal position rate was calculated based on these defined criteria.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003e2.6 Statistical analysis\u003c/h2\u003e \u003cp\u003eFrequency (percentages) were used to present categorical variables whereas continuous variables were presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (SD). Quantitative data was analyzed using independent samples t-tests. Pearson\u0026rsquo;s correlation analysis was used to analyze the correlation between demographic information, measured lengths and imaging measurement results. The statistical significance was set at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05. The statistical analyses were performed using version 29.0 of the SPSS software (IBM Corp, Armonk, NY). The graphical representations in this study were created using the R programming language. Various packages were employed, such as the GGally, rstatix, and ggplot2 packages.\u003c/p\u003e \u003c/div\u003e"},{"header":"3 Results","content":"\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Clinical characteristics of patients\u003c/h2\u003e \u003cp\u003eDuring the study period, 263 patients met the inclusion criteria, of whom 211 were included in the final analysis dataset after the exclusion of 52 patients (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows patients' clinical characteristics. Among the patients, there were 133 male patients (63.0%) and 78 female patients (37.0%). The median age of all patients at the examination was 62 years (range, 13\u0026ndash;80 years). The average height was 166.25\u0026thinsp;\u0026plusmn;\u0026thinsp;6.50 cm, the average weight was 62.76\u0026thinsp;\u0026plusmn;\u0026thinsp;9.57 kg, and the average body mass index (BMI) was 22.68\u0026thinsp;\u0026plusmn;\u0026thinsp;3.07 kg/m\u003csup\u003e2\u003c/sup\u003e. Male patients had an average height and weight higher than that of female patients, but there was no statistically significant difference in BMI.\u003c/p\u003e \u003cp\u003eThe average catheter length for all patients was 21.29\u0026thinsp;\u0026plusmn;\u0026thinsp;1.25 cm, with a longer length observed in male patients compared to female patients (21.46\u0026thinsp;\u0026plusmn;\u0026thinsp;1.20 cm vs. 20.99\u0026thinsp;\u0026plusmn;\u0026thinsp;1.29 cm; p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The mean length of AB was also longer in male patients than in female patients (4.63\u0026thinsp;\u0026plusmn;\u0026thinsp;0.98 cm vs. 4.26\u0026thinsp;\u0026plusmn;\u0026thinsp;0.97 cm; p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Furthermore, the mean length of VBU was longer in male patients than in female patients (25.80\u0026thinsp;\u0026plusmn;\u0026thinsp;3.18 mm vs. 24.61\u0026thinsp;\u0026plusmn;\u0026thinsp;2.61 mm; p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). However, there were no statistically significant statistical variations in the length of AC, the distance from the carina to the tip, the distance from the carina to the CAJ, and the distance from the carina to the tip measured by the VBU between male and female patients.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eClinical characteristics of patients\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCharacteristics\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAll (N\u0026thinsp;=\u0026thinsp;211)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMale (n\u0026thinsp;=\u0026thinsp;133)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eFemale\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;78)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge, years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e62 (13\u0026ndash;80)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e65 (13\u0026ndash;80)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e57 (19\u0026ndash;78)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeight, cm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e166.25\u0026thinsp;\u0026plusmn;\u0026thinsp;6.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e168.79\u0026thinsp;\u0026plusmn;\u0026thinsp;5.73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e161.91\u0026thinsp;\u0026plusmn;\u0026thinsp;5.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWeight, kg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e62.76\u0026thinsp;\u0026plusmn;\u0026thinsp;9.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e64.31\u0026thinsp;\u0026plusmn;\u0026thinsp;9.86\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e60.12\u0026thinsp;\u0026plusmn;\u0026thinsp;8.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.002\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI, kg/m\u0026sup2;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22.68\u0026thinsp;\u0026plusmn;\u0026thinsp;3.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22.54\u0026thinsp;\u0026plusmn;\u0026thinsp;3.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e22.93\u0026thinsp;\u0026plusmn;\u0026thinsp;2.95\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.378\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLength of catheter, cm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21.29\u0026thinsp;\u0026plusmn;\u0026thinsp;1.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21.46\u0026thinsp;\u0026plusmn;\u0026thinsp;1.20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e20.99\u0026thinsp;\u0026plusmn;\u0026thinsp;1.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.008\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAB, cm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4.49\u0026thinsp;\u0026plusmn;\u0026thinsp;0.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.63\u0026thinsp;\u0026plusmn;\u0026thinsp;0.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.26\u0026thinsp;\u0026plusmn;\u0026thinsp;0.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.008\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAC, cm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9.81\u0026thinsp;\u0026plusmn;\u0026thinsp;1.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.86\u0026thinsp;\u0026plusmn;\u0026thinsp;1.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e9.74\u0026thinsp;\u0026plusmn;\u0026thinsp;1.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.470\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVBU, mm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25.36\u0026thinsp;\u0026plusmn;\u0026thinsp;3.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25.80\u0026thinsp;\u0026plusmn;\u0026thinsp;3.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e24.61\u0026thinsp;\u0026plusmn;\u0026thinsp;2.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.004\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCarina-tip, mm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18.76\u0026thinsp;\u0026plusmn;\u0026thinsp;10.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18.45\u0026thinsp;\u0026plusmn;\u0026thinsp;10.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e19.29\u0026thinsp;\u0026plusmn;\u0026thinsp;9.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.576\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCarina-CAJ, mm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e41.31\u0026thinsp;\u0026plusmn;\u0026thinsp;6.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e41.21\u0026thinsp;\u0026plusmn;\u0026thinsp;6.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e41.48\u0026thinsp;\u0026plusmn;\u0026thinsp;6.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.771\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCarina-tip/VBU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.74\u0026thinsp;\u0026plusmn;\u0026thinsp;0.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.72\u0026thinsp;\u0026plusmn;\u0026thinsp;0.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.78\u0026thinsp;\u0026plusmn;\u0026thinsp;0.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.299\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e \u003cp\u003eBMI, body mass index; AB, the distance from the puncture point (Point A) to the right clavicular notch (Point B); AC, the distance from the puncture point (Point A) to the port (Point C); VBU, vertebral body unit; CAJ, caval-atrial junction.\u003c/p\u003e \u003cp\u003eValues are reported as median (range) or mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003e3.2 Imaging measurement on CXR\u003c/h2\u003e \u003cp\u003eThe CXR images showed that the mean distance between the carina and the catheter tip, as measured by the VBU, was 0.74\u0026thinsp;\u0026plusmn;\u0026thinsp;0.41 VUBs (95% CI -0.06\u0026ndash;1.55; Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. A). The VBU measurement also revealed an optimal positioning rate of 94.31% (199/211). Meanwhile, direct measurements in length showed that the mean distance from the carina to the catheter tip was 18.76\u0026thinsp;\u0026plusmn;\u0026thinsp;10.50 mm (95% CI -1.81\u0026ndash;39.33; Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. B). The optimal positioning rate based on direct measurements was 92.42% (195/211).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003e3.3 Characteristics related to catheter length\u003c/h2\u003e \u003cp\u003eIn the multivariate correlation analysis, as depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, weak but statistically significant associations between catheter length and various factors were observed. Specifically, there were weak but significant associations between catheter length and height (r\u0026thinsp;=\u0026thinsp;0.325, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), weight (r\u0026thinsp;=\u0026thinsp;0.276, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), VBU (r\u0026thinsp;=\u0026thinsp;0.232, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), and the distance from the carina to the CAJ (r\u0026thinsp;=\u0026thinsp;0.167, p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The study revealed that there are comparable connections between the length of catheter AC and height (r\u0026thinsp;=\u0026thinsp;0.185, p\u0026thinsp;\u0026lt;\u0026thinsp;0.01), weight (r\u0026thinsp;=\u0026thinsp;0.235, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), BMI (r\u0026thinsp;=\u0026thinsp;0.164, p\u0026thinsp;\u0026lt;\u0026thinsp;0.05), and VBU (r\u0026thinsp;=\u0026thinsp;0.171, p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Additionally, a minor yet substantial correlation was observed between the length of catheter AB and height (r\u0026thinsp;=\u0026thinsp;0.206, p\u0026thinsp;\u0026lt;\u0026thinsp;0.01). Conclusively, these results suggest that the height and weight of patients do have a certain impact on the length of catheters. No significant correlations were found between the distance from the carina to the CAJ and variables such as age, height, weight, or BMI. As a result, we can infer that there is no link between the distance from the carina to the CAJ and factors such as age, height, weight, or sex.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"4 Discussion","content":"\u003cp\u003eThis retrospective study aimed to evaluate the reliability of a modified surface measurement method for determining the optimal catheter length of TIVAP catheters implanted via the right internal jugular vein in a cohort of 211 patients. The results demonstrate that this measurement method for catheter length contributed to a high rate of optimal catheter tip placement, as confirmed by CXR. This demonstrates the method's reliability and its applicability in clinical practice.\u003c/p\u003e \u003cp\u003eThe optimal location of the catheter tip is still controversial. The American Society for Intravenous Infusion Nursing (INS) recommends placing the central venous catheter tip in the lower third of the SVC, at or near the CAJ, to optimize positioning.\u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e The European Society for Medical Oncology (ESMO) guidelines advocate placing the central venous catheter tip at the CAJ.\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e While the European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines suggest that the ideal catheter tip location includes the inferior 1/3 part of the SVC, the CAJ, and the upper region of the right atrium within 2cm below the CAJ.\u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e A retrospective study reported by Caers et al in 437 patients found that placing the catheter tip in the inferior 1/3 of the SVC resulted in the lowest incidence of thrombosis and catheter dysfunction.\u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e Some prior reports have warned against placing the catheter tip inside the heart, as it may result in serious complications.\u003csup\u003e\u003cspan additionalcitationids=\"CR18\" citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e In 1989, the US Food and Drug Administration required that the central venous catheter tip should be avoided from being placed or displaced inside the heart.\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e While some studies have reported that locating the catheter tip low in the SVC or the right atrium enhances catheter performance and blood flow.\u003csup\u003e\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e,\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u003c/sup\u003e Therefore, there remains a debate about whether the upper right atrium can be considered an ideal catheter tip location. To prioritize patient safety, we have chosen the lower third of the SVC at or near the CAJ as the preferred catheter tip position.\u003c/p\u003e \u003cp\u003eSurface measurements, which involve assessing distances between specific anatomical landmarks, are frequently used to determine the appropriate catheter length for both PICC and TIVAP placement. Nevertheless, no universally recognized and accurate method of surface measurement currently exists. The surface measurement method for catheter length determination, as recommended by ONS, is widely used but can be influenced by factors such as obesity.\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e Previous studies have shown that catheter lengths determined by this surface measurement method tend to be longer than those determined by intracardiac electrocardiogram measurement and are associated with a higher incidence of complications.\u003csup\u003e\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e,\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u003c/sup\u003e To address these concerns, we have modified the surface measurement method based on our clinical experience. Previous studies have demonstrated that using the internal jugular vein route may be associated with a lower risk of mechanical complications compared to the subclavian route.\u003csup\u003e\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u003c/sup\u003e The SVC originates from the convergence of the left and right brachiocephalic veins, with a length of approximately 7 cm. Its starting point is posterior to the first right costal cartilage and the sternum. Given that the right clavicular notch is adjacent to the upper edge of the first right costal cartilage, an additional 7 cm below the right clavicular notch ensures that the catheter tip is positioned in the lower third of the SVC, close to the CAJ, without extending too deeply into the right atrium. And clavicular notch is easily identified by palpation.\u003csup\u003e\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eCXR serves as the primary method for verifying the position of the catheter tip following TIVAP implantation. To establish the CAJ as a sound reference point, it necessitates consistent and repeatable identification of anatomical landmarks on the CXR. Various radiographic landmarks are employed for this purpose, including ribs, vertebral bodies, the right bronchus, cardiac silhouette, and the carina. Among these, the carina has consistently proven to be a reliable landmark for confirming the catheter tip's placement. In all cases, the pericardial sac terminates below the level of the carina. And the carina is readily noticeable, even in lower-quality chest X-ray images.\u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e,\u003cspan additionalcitationids=\"CR28 CR29 CR30\" citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e\u003c/sup\u003e Furthermore, the VBU is employed as a quantification unit on CXR. Song et al. measured the distance from the carina to the CAJ in adult patients between 40\u0026ndash;88 years old using CXR and found it to be 2.4 VBUs.\u003csup\u003e\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e However, their study did not include adolescent or young adult populations. Baskin et al. carried out research on 100 young patients aged 12\u0026ndash;28 years, which suggests that the position of the CAJ can be estimated as 2 VBUs below the carin.\u003csup\u003e\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u003c/sup\u003e Similarly, Johnston et al. arrived at a similar conclusion when studying 499 older adults.\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e Wright et al. proposed a \"final tip position window\" bordering 2 VBUs below the carina on CXR.\u003csup\u003e\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e\u003c/sup\u003e In 2023, the Consensus of Central Venous Access Working Group, part of the Chinese Association of Integrative Medicine Peripheral Vascular Disease Committee, recommended the anatomical reference location for the CAJ to be 2 VBUs below the carina.\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e Our study has identified the catheter tip's optimal position as being within 2 VBUs below the carina. Based on this criterion, the majority of participants in our study achieved the optimal position. Additionally, several earlier investigations have consistently found that the distance between the carina and CAJ is approximately 40mm across all age ranges. Notely, this distance displayed no correlation with height, weight, body surface area, or gender.\u003csup\u003e\u003cspan additionalcitationids=\"CR35 CR36\" citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e\u003c/sup\u003e We also observed no significant associations between the distance from the carina to the CAJ and factors such as sex, age, height, and weight. The consensus of Shanghai experts in 2015 proposed that the catheter should be positioned under the carina at an average distance of 40.3\u0026thinsp;\u0026plusmn;\u0026thinsp;13.6 mm on CXR.\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e By referring to this recommendation, 92.42% of patients in our study achieved the optimal position, further demonstrating the reliability of our modified surface measurement method. Many researchers advocate using the VBU as a ruler to determine the position of the catheter tip. The spine, which is minimally affected by geometric magnification and adaptable to somatic growth, plays a significant role in ensuring accurate catheter placement and measurements.\u003csup\u003e\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e,\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u003c/sup\u003e We recognize the rationale in this viewpoint, thus we endorse the results measured by VBU as a preferred reference.\u003c/p\u003e \u003cp\u003eThere are certain limitations associated with CXRs, including the potential for subjectivity in interpreting tip positions,\u003csup\u003e\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e\u003c/sup\u003e and the dynamic movement of the catheter tip due to factors such as patient positioning, respiration, and arm movements.\u003csup\u003e\u003cspan additionalcitationids=\"CR40\" citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e\u003c/sup\u003e These factors can result in measurement discrepancies among different patients. To address these issues and improve result accuracy, various measures were implemented. Specifically, we contracted several experienced radiologists to interpret the chest X-rays. Furthermore, we standardized the patients\u0026rsquo; position during the radiographic procedures. Additionally, our multivariate correlation analysis revealed weak but statistically significant correlations between catheter length and patient height and weight. In 1990, Peres developed formulas based on patient height to predict the optimal catheter length of catheters.\u003csup\u003e\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e\u003c/sup\u003e We also attempted to utilize patient height and weight to estimate catheter length. However, despite applying multiple linear regression analysis, the model demonstrated limited fitting and applicability, suggesting the need for further exploration and adjustment with a larger sample size.\u003c/p\u003e"},{"header":"5 Conclusion","content":"\u003cp\u003eIn conclusion, we have designed and validated a modified surface measurement method for determining the catheter length of the TIVAP inserted via the right internal jugular vein. This method demonstrated a high degree of reliability in locating the optimal tip position and was validated by CXR.\u003c/p\u003e \u003cp\u003e \u003cb\u003eDeclaration of conflicting interests\u003c/b\u003e \u003c/p\u003e \u003cp\u003eThe Authors declare that there is no conflict of interest.\u003c/p\u003e \u003cp\u003e \u003cstrong\u003eConsent to Publish\u003c/strong\u003e \u003cp\u003e \u003cb\u003edeclaration\u003c/b\u003e \u003c/p\u003e \u003c/p\u003e \u003cp\u003eNot Applicable.\u003c/p\u003e \u003cp\u003e \u003cstrong\u003eConsent to Participate\u003c/strong\u003e \u003cp\u003e \u003cb\u003edeclaration\u003c/b\u003e \u003c/p\u003e \u003c/p\u003e \u003cp\u003eNot Applicable.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eDeclaration of conflicting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe Authors declare that there is no conflict of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Publish declaration\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot Applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Participate declaration\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot Applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical approval\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEthical approval for this study was granted by the Institutional Ethics Committee of Zhongnan Hospital of Wuhan University (ethical approval number: 2023063k).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eContributorship\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eResearch Conception and Design: Weijun Fang, Mengting Chen and Hao Zou; Data collection: Weijun Fang, Hao Zou and Guanguan Luo; Data Analysis and Interpretation: Mengting Chen and Jun Shen; Writing the Manuscript: Mengting Chen; Critical Revision: Weijun Fang, Hao Zou and Jun Shen.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;Acknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe would like to thank the emergency department physicians and radiologists at Zhongnan Hospital of Wuhan University for their contributions to this research.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eZhang K-C, Chen L. 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The carina as a radiological landmark for central venous catheter tip position. \u003cem\u003eBritish Journal of Anaesthesia\u003c/em\u003e 2006; 96: 335\u0026ndash;340.\u003c/li\u003e\n\u003cli\u003eAlbrecht K, Nave H, Breitmeier D, et al. Applied anatomy of the superior vena cava\u0026mdash;the carina as a landmark to guide central venous catheter placement. \u003cem\u003eBritish Journal of Anaesthesia\u003c/em\u003e 2004; 92: 75\u0026ndash;77.\u003c/li\u003e\n\u003cli\u003eRyu H-G, Bahk J-H, Kim J-T, et al. Bedside prediction of the central venous catheter insertion depth. \u003cem\u003eBritish Journal of Anaesthesia\u003c/em\u003e 2007; 98: 225\u0026ndash;227.\u003c/li\u003e\n\u003cli\u003eCaruso LJ, Gravenstein N, Layon AJ, et al. A better landmark for positioning a central venous catheter. \u003cem\u003eJ Clin Monit Comput\u003c/em\u003e 2002; 17: 331\u0026ndash;334.\u003c/li\u003e\n\u003cli\u003eBaskin KM, Jimenez RM, Cahill AM, et al. 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A retrospective two-center cohort study on the use of routine chest X-ray after peripherally inserted central catheter placement under ultrasound and intracavitary electrocardiography guidance. \u003cem\u003eAnn Transl Med\u003c/em\u003e 2022; 10: 1315\u0026ndash;1315.\u003c/li\u003e\n\u003cli\u003eRidge CA, Litmanovich D, Molinari F, et al. Radiographic Evaluation of Central Venous Catheter Position. \u003cem\u003eJournal of Thoracic Imaging\u003c/em\u003e 2013; 28: 129\u0026ndash;133.\u003c/li\u003e\n\u003cli\u003eChan TY, England A, Meredith SM, et al. Radiologist variability in assessing the position of the cavoatrial junction on chest radiographs. \u003cem\u003eBJR\u003c/em\u003e 2016; 89: 20150965.\u003c/li\u003e\n\u003cli\u003eKowalski CM, Kaufman JA, Rivitz SM, et al. Migration of Central Venous Catheters: Implications for Initial Catheter Tip Positioning. \u003cem\u003eJournal of Vascular and Interventional Radiology\u003c/em\u003e 1997; 8: 443\u0026ndash;447.\u003c/li\u003e\n\u003cli\u003eGnannt R, Connolly BL, Parra DA, et al. Variables decreasing tip movement of peripherally inserted central catheters in pediatric patients. \u003cem\u003ePediatr Radiol\u003c/em\u003e 2016; 46: 1532\u0026ndash;1538.\u003c/li\u003e\n\u003cli\u003eConnolly B, Amaral J, Walsh S, et al. Influence of arm movement on central tip location of peripherally inserted central catheters (PICCs). \u003cem\u003ePediatr Radiol\u003c/em\u003e 2006; 36: 845\u0026ndash;850.\u003c/li\u003e\n\u003cli\u003ePeres PW. Positioning Central Venous Catheters \u0026ndash; A Prospective Survey. \u003cem\u003eAnaesth Intensive Care\u003c/em\u003e 1990; 18: 536\u0026ndash;539.\u003cstrong\u003e\u003c/strong\u003e\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Totally implantable venous access port, Right internal jugular vein, Surface measurement, Catheter length","lastPublishedDoi":"10.21203/rs.3.rs-6512487/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6512487/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eThe accurate determination of the optimal length of catheters for Totally Implantable Venous Access Ports (TIVAP) is crucial to prevent complications and improve patient care. This study sought to evaluate the reliability of a modified surface measurement method for determining the ideal tip position of TIVAP catheters inserted via the right internal jugular vein.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eA retrospective study was conducted, involving a total of 211 patients diagnosed with malignant neoplasms, who underwent TIVAP implantation. A modified surface measurement method was employed to accurately determine the appropriate catheter length for TIVAP placement. This involved measuring the distance from the puncture point (Point A) to the right clavicular notch (Point B), denoted as AB, as well as the distance from the puncture point (Point A) to the portal body (Point C), denoted as AC. The catheter length was then calculated using the equation: catheter length (cm)\u0026thinsp;=\u0026thinsp;AB\u0026thinsp;+\u0026thinsp;AC\u0026thinsp;+\u0026thinsp;7. The position of the catheter tip was assessed through the use of chest radiography (CXR).\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe mean length of the catheter implanted in all patients was 21.29\u0026thinsp;\u0026plusmn;\u0026thinsp;1.25 cm (male vs. female, 21.46\u0026thinsp;\u0026plusmn;\u0026thinsp;1.20 cm vs. 20.99\u0026thinsp;\u0026plusmn;\u0026thinsp;1.29 cm; p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The optimal positioning rate, determined by the vertebral body unit (VBU) measurement, was found to be 94.31%. Additionally, the optimal placement rate based on direct measurement was 92.42%. There were weak but statistically significant associations between the catheter length and the height and weight of patients.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eA revised method for measuring the catheter length of TIVAP via the right internal jugular vein has been developed using surface measurements. This method has been proven to be highly reliable in locating the optimum tip position and was verified by CXR.\u003c/p\u003e","manuscriptTitle":"A Modified Surface Measurement Method to Determine Catheter Length of Totally Implantable Venous Access Port Via the Right Internal Jugular Vein","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-03 13:20:40","doi":"10.21203/rs.3.rs-6512487/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"f89f2bc8-c682-4a8c-aa78-331e3a1c63a7","owner":[],"postedDate":"June 3rd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-06-30T16:38:37+00:00","versionOfRecord":[],"versionCreatedAt":"2025-06-03 13:20:40","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6512487","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6512487","identity":"rs-6512487","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}