Point-of-care ultrasound for vascular access in neonates and children.

Ultrasound plays a major role in neonatal/pediatric vascular access, both for venous access and for arterial access, not only just for the insertion of intravascular catheters, but also for many other issues related to this type of maneuver. This "global use of ultrasound" includes a systematic and consistent adoption of this technology for several steps of vascular access: (a) the pre-procedural assessment/evaluation of the vessels, (b) the ultrasound-guided puncture and cannulation of arteries and veins, (c) the real-time diagnosis of immediate, puncture-related complications, (d) the so-called "tip navigation" (i.e., real-time intra-procedural assessment of the direction and trajectory of the guidewire and/or of the catheter inside the vasculature), (e) the so-called "tip location" (i.e., intra-procedural or post-procedural assessment of the proper position of the tip of the catheter), and (f) the early diagnosis and/or management of most non-infective late complications. CONCLUSION: Therefore, any vascular access expert (nurse or physicians) should have documented competency in the use of ultrasound. This knowledge should include the use of ultrasound for assessment of vessels, for catheter insertion, for proper placement of the tip, and for real-time detection of complications. WHAT IS KNOWN: • Ultrasound is obviously useful for vascular access procedures in neonates and children. WHAT IS NEW: • Recent evidence suggests that ultrasound is useful for many purposes in the field of vascular access (preprocedural scan, ultrasound-guided puncture, tip navigation, tip location, diagnosis of most non-infective complications). • Recent evidence also suggests that radiological methods no longer play any role in the insertion of vascular accesses in neonates and children.

Optimal Insertion Depth of Central Venous Catheter through the Right Internal Jugular Vein, Verified by Transesophageal Echocardiography: A Prospective Observational Study.

This prospective observational study investigated the optimal insertion depth of the central venous catheter through the right internal jugular vein using transesophageal echocardiography. After tracheal intubation, the anesthesiologist inserted a probe for esophageal echocardiography into the patient's esophagus. The investigators placed the catheter tip 2 cm above the superior edge of the crista terminalis with echocardiography, which was defined as the optimal point. We measured the inserted length of the catheter. Pearson correlation tests were performed with the measured optimal depth and some patient parameters. We made a new formula for placing the catheter at the optimal position. A total of 89 subjects were enrolled in this trial. The correlation coefficient between the measured optimal depth and the patient's parameters was the highest for patient height (0.703, p < 0.001). We made a new formula of 'height (cm)/10 - 1.5 cm'. The accuracy rate of this formula for the optimal zone was 71.9% (95% confidence interval; 62.4 - 81.4%), which was the highest among the previous formulas or guidelines when we compared. In conclusion, the central venous catheter tip was evaluated with transesophageal echocardiography, and we could make a new formula of 'height (cm)/10 - 1.5', which seemed to be better than other previous guidelines.

Ultrasound-guided central venous catheterization around the neck: Systematic review and network meta-analysis.

BACKGROUND: Ultrasound-guided central venous catheterization (CVC) has become the standard of care. However, providers use a variety of approaches, encompassing the internal jugular vein (IJV), supraclavicular subclavian vein (SupraSCV), infraclavicular subclavian vein (InfraSCV), proximal axillary vein (ProxiAV), distal axillary vein (DistalAV), and femoral vein. OBJECTIVE: This review aimed to compare the first-pass success rate and arterial puncture rate for different approaches to ultrasound-guided CVC above the diaphragm. METHODS: In May 2023, Embase, MEDLINE, CENTRAL, ClinicalTrials.gov, and World Health Organization International Clinical Trials Platform were searched for randomized controlled trials (RCTs) comparing the 5 CVC approaches. The Confidence in Network Meta-Analysis tool was used to assess confidence. Thirteen RCTs (4418 participants and 13 comparisons) were included in this review. RESULTS: The SupraSCV approach likely increased the proportion of first-attempt successes compared to the other 4 approaches. The SupraSCV first-attempt success demonstrated risk ratios (RRs) > 1.21 with a lower 95% confidence interval (CI) exceeding 1. Compared to the IJV, the SupraSCV approach likely increased the first-attempt success proportion (RR 1.22; 95% confidence interval [CI] 1.06-1.40, moderate confidence), whereas the DistalAV approach reduced it (RR 0.72; 95% CI 0.59-0.87, high confidence). Artery puncture had little to no difference across all approaches (low to high confidence). CONCLUSION: Considering first-attempt success and mechanical complications, the SupraSCV may emerge as the preferred approach, while DistalAV might be the least preferable approach. Nevertheless, head-to-head studies comparing the approaches with the greatest first attempt success should be undertaken.

Macro- and microscopic changes in veins with short-term central venous catheters: an observational autopsy study.

BACKGROUND: Centrally inserted central catheters (CICCs) are indispensable in modern healthcare, but unfortunately, come with complications. Catheter-related thrombosis is a well-known complication reported to occur in 5-30% of patients with CICC. There is a paucity of studies that report the incidence of catheter-related thrombosis after the introduction of real-time ultrasound insertion guidance as clinical practice. This study aimed to demonstrate any pathological macro- or microscopic changes in the vein wall associated with CICCs. METHODS: The study was approved by the Swedish Ethical Review Authority and was conducted at a large university hospital. The study included 12 patients with a short-term CICC who were subject to autopsies. Vessels with inserted catheters were macroscopically and microscopically examined. RESULTS: In total, seven female and five male patients with a median age of 70 (interquartile range 63-76) were included. With one exception, all patients received routine thromboprophylaxis throughout the period with CICC. Most inserted CICCs were 9.5 French (54%) and were inserted in the internal jugular vein (92%). The median time with CICC was seven days (interquartile range 1.8-20). At autopsy, thrombi were observed in all cases (100%), macroscopically and microscopically, attached to the distal portion of the CICC and/or the adjacent vessel wall. Inflammatory changes in the vessel walls were seen in all cases, and varying degrees of fibrosis were demonstrated in eight cases (67%). CONCLUSIONS: This autopsy study demonstrated that catheter-related thrombus formation with adjacent inflammatory and fibrotic vessel wall thickening was very common, despite a limited period of catheter use. The consequences of these findings are important, as thrombi may cause pulmonary embolism and possibly lead to catheter-related infections, and since inflammatory and fibrotic vessel wall thickening may evolve into chronic venous stenosis. Furthermore, the findings are a cause of concern, as CICCs are indispensable in modern healthcare and complications may be masked by the general disease that was the indication for CICC insertion.

Comparison of the Ultrasound-Guided Supraclavicular and Infraclavicular Approaches for Subclavian Vein Cannulation in Children With Congenital Heart Disease.

OBJECTIVES: Central venous catheterization is used widely in critical pediatric patients. The authors sought to compare the success rate and safety of ultrasound-guided subclavian vein cannulation performed via infraclavicular and supraclavicular approaches. DESIGN: The authors compared the success rate of the first puncture and other information for cannulation in the children with congenital heart disease requiring central venous catheterization who were assigned randomly to the supraclavicular approach group (group A) or infraclavicular approach group (group B). SETTING: Medical university hospital pediatric cardiac intensive care units. PARTICIPANTS: Pediatric patients diagnosed with congenital heart disease in the preoperative period who were admitted to the cardiac intensive care unit and required subclavian vein catheterization. INTERVENTIONS: Ultrasound-guided subclavian vein cannulation. MEASUREMENTS AND MAIN RESULTS: Sixty-seven children were included in the study, with 32 in group A and 35 in group B. Notably, there was a significant difference in the success rate of the first puncture between groups A and B (90.6% v 71.4, %, p = 0.047). Furthermore, the access time in group A was 11.8 seconds (3.2-95), which was significantly shorter than that in group B (16.0 [6.5-227] seconds, p = 0.001). In addition, the catheter malposition rate in group A was significantly lower than that in group B (0% v 11.4%, p = 0.049). Conversely, there were no significant differences in the total access time, overall success rate, and complications (eg, pneumothorax, hemorrhage, puncture artery, and nerve injury) between the 2 groups. CONCLUSIONS: For children with congenital heart disease requiring central venous catheterization during the perioperative period, the subclavian vein is a feasible site for catheterization. The supraclavicular approach, especially the left side, has a higher first-puncture success rate, shorter access time, lower complications, and a trend of lower incidence of catheter malposition. However, a larger sample size of a randomized controlled study is expected to verify the advantages of ultrasound-guided subclavian catheterization in children.

Virtual Reality Training for Central Venous Catheter Placement: An Interventional Feasibility Study Incorporating Virtual Reality Into a Standard Training Curriculum of Novice Trainees.

OBJECTIVES: This study assess the feasibility of integrating virtual reality (VR) simulation into the central venous catheter (CVC) placement training curriculum. DESIGN: The study consists of 3 parts: (1) Evaluating current manikin-based training for CVC placement through surveys for senior first-year anesthesia residents and cardiac anesthesia faculty who supervise resident performing the procedure; (2) Interventional study training novice trainees with VR simulator and assessing their reaction satisfaction; and (3) pilot study integrating VR training sessions into CVC training curriculum for first-year anesthesia residents. SETTING: Conducted at a single academic-affiliated medical center from December 2022 to August 2023. PARTICIPANTS: Junior first-year anesthesia residents. INTERVENTIONS: VR training sessions for CVC placements using the Vantari VR system. MEASUREMENTS AND MAIN RESULTS: Primary outcome: novice trainees' satisfaction with VR training for CVC procedure. Satisfaction of resident and faculty with standard manikin-based training was also collected. Faculty expressed concerns about residents' confidence and perceived knowledge in performing CVC placement independently. Novice trainees showed high satisfaction and perceived usefulness with VR training, particularly in understanding procedural steps and developing spatial awareness. Pilot integration of VR training into the curriculum demonstrated comparable training times and emphasized structured stepwise training modules to ensure completion of vital procedural steps. CONCLUSIONS: This study underscores the potential of VR simulation as a complementary training tool for CVC placement rather than a substitution of standard manikin training. VR is offering immersive experiences and addressing limitations of traditional manikin-based training methods. The integration of VR into training curricula warrants further exploration to optimize procedural proficiency and patient safety in clinical practice.

Ultrasound-guided selective supraclavicular nerve block for postoperative pain control in children receiving Hickman catheter or chemoport insertion: A randomized controlled trial.

BACKGROUND: Optimal pain management after insertion of a central venous catheter in children remains unclear. AIM: This study aimed to evaluate the effects of a selective supraclavicular nerve block on postoperative analgesia in pediatric patients undergoing hickman catheter or chemoport insertion. METHODS: Fifty patients aged 3-18 years scheduled for elective Hickman or chemoport insertion were randomized into two groups of 25 each: one group received an ultrasound-guided selective supraclavicular nerve block with 0.1 mL/kg of 0.5% ropivacaine (SSCNB group), and the other group did not receive a nerve block (control group). The primary outcome was the postoperative Wong-Baker Faces Pain Rating Scale score measured between 10 and 30 min after surgery. Secondary outcomes included pain scores at 1, 3, and 24 h after the surgery, block-related complications, length of stay in the postanesthesia care unit, postoperative analgesic consumption, and time to first analgesic use 24 h after surgery. RESULTS: The worst pain score within 30 min in the recovery room was significantly lower in the SSCNB group compared to the control group (6 [5-7] vs. 3 [2-4]; median difference, -3; 95% CI, -4 to -1; p < .001). Pain scores at 1, 3, and 24 h after surgery were also significantly lower in the SSCNB group. The need for both opioid and non-opioid analgesics in the postoperative period was significantly lower in the SSCNB group (36.0% vs. 0%; p = .002 and 44.0% vs. 16.0%; mean difference, -28%; 95% CI, -56 to 0.19; p = .033, respectively), while other secondary outcomes were not significantly different between the two groups. CONCLUSIONS: Ultrasound-guided SSCNB is an effective method for managing postoperative pain in children undergoing Hickman catheter or chemoport insertion, reducing the need for analgesics within 24 h after surgery.

Case series of peripherally inserted central catheter insertion in young children: A new approach to the axillary vein.

BACKGROUND: We have developed a new approach for peripherally inserted central catheter (PICC) insertion that we think has several advantages, including ease of insertion, access to a larger vein and patient comfort. METHODS: In this case series report, the first 19 cases were audited. RESULTS: All PICCs were inserted without complications; 17 on the first attempt. CONCLUSION: We conclude that the novel approach to the axillary vein for PICC insertion is feasible and appears to be safe when performed by an experienced operator.

Implementation frameworks, strategies and outcomes in optimizing central venous access device practice in paediatrics: A scoping review.

Paediatric patients with complex or acute conditions may require a central venous access device, however, almost one-third of these devices have associated complications (e.g. infections). Implementation of evidence-based practices regarding central venous access devices can reduce and potentially prevent complications. AIMS: This scoping review aimed to explore recent interventional research in CVAD management through an implementation lens. DESIGN: This scoping review used the Arksey and O'Malley framework. Studies were included if they were written in English, published in 2012 to July 2023, involved children and were relevant to the study aims. Risk of bias was appraised by the Mixed Methods Appraisal Tool. DATA SOURCES: Searches were undertaken in EMBASE, CINAHL (Ebsco), PubMed, Web of Science and Cochrane Library (CENTRAL). RESULTS: Of the 1769 studies identified in a systematic search, 46 studies were included. Studies mostly focused on health professionals and central venous access device maintenance and had quantitative pre-post study designs. Adherence to implementation frameworks was lacking, with many studies employing quality improvement approaches. Implementation strategies were typically multipronged, using health-professional education, bundles and working groups. Bundle compliance and reductions in central line-associated bloodstream infections were the most featured outcomes, with most studies primarily focusing on effectiveness outcomes. CONCLUSION: Translation of evidence-based practices to the clinical setting is difficult and current adoption of implementation frameworks (apart from 'quality improvement') is limited. Implementation strategies are diverse and dependent on the local context, and study outcomes typically focus on the effectiveness of the physical intervention, rather than measuring the implementation effort itself. IMPLICATIONS FOR PATIENTS: Future intervention research requires a more uniform and deliberate application of implementation frameworks and strategies. IMPACT: Greater exploration of relationships between frameworks and strategies and implementation and service outcomes is required to increase understanding of their role in maximizing resources to improve health care. Adhered to best reporting guidelines as per PRISMA-ScR (Tricco et al., 2018). PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.

Evaluating the effects of comprehensive simulation on central venous catheterization training: a comparative observational study.

BACKGROUND: Simulation-based training (SBT) is vital to complex medical procedures such as ultrasound guided central venous catheterization (US-IJCVC), where the experience level of the physician impacts the likelihood of incurring complications. The Dynamic Haptic Robotic Trainer (DHRT) was developed to train residents in CVC as an improvement over manikin trainers, however, the DHRT and manikin trainer both only provide training on one specific portion of CVC, needle insertion. As such, CVC SBT would benefit from more comprehensive training. An extended version of the DHRT was created, the DHRT + , to provide hands-on training and automated feedback on additional steps of CVC. The DHRT + includes a full CVC medical kit, a false vein channel, and a personalized, reactive interface. When used together, the DHRT and DHRT + systems provide comprehensive training on needle insertion and catheter placement for CVC. This study evaluates the impact of the DHRT + on resident self-efficacy and CVC skill gains as compared to training on the DHRT alone. METHODS: Forty-seven medical residents completed training on the DHRT and 59 residents received comprehensive training on the DHRT and the DHRT + . Each resident filled out a central line self-efficacy (CLSE) survey before and after undergoing training on the simulators. After simulation training, each resident did one full CVC on a manikin while being observed by an expert rater and graded on a US-IJCVC checklist. RESULTS: For two items on the US-IJCVC checklist, "verbalizing consent" and "aspirating blood through the catheter", the DHRT + group performed significantly better than the DHRT only group. Both training groups showed significant improvements in self-efficacy from before to after training. However, type of training received was a significant predictor for CLSE items "using the proper equipment in the proper order", and "securing the catheter with suture and applying dressing" with the comprehensive training group that received additional training on the DHRT + showing higher post training self-efficacy. CONCLUSIONS: The integration of comprehensive training into SBT has the potential to improve US-IJCVC education for both learning gains and self-efficacy.

Competence over confidence: uncovering lower self-efficacy for women residents during central venous catheterization training.

BACKGROUND: While women make up over 50% of students enrolled in medical school, disparities in self-efficacy of medical skills between men and women have been observed throughout medical education. This difference is significant because low self-efficacy can impact learning, achievement, and performance, and thus create gender-confidence gaps. Simulation-based training (SBT) employs assessments of self-efficacy, however, the Dunning-Kruger effect in self-assessment posits that trainees often struggle to recognize their skill level. Additionally, the impact of gender on self-efficacy during SBT has not been as widely studied. The objective of this study was to identify if the gender-confidence gap and the Dunning-Kruger effect exist in SBT for central venous catheterization (CVC) on the dynamic haptic robotic trainer (DHRT) utilizing comparisons of self-efficacy and performance. METHODS: 173 surgical residents (Nwomen=61, Nmen=112) underwent training on the DHRT system over two years. Before and after using the DHRT, residents completed a 14-item Central Line Self-Efficacy survey (CLSE). During training on the DHRT, CVC performance metrics of the number of insertion attempts, backwall puncture, and successful venipuncture were also collected. The pre- and post-CLSE, DHRT performance and their relationship were compared between men and women. RESULTS: General estimating equation results indicated that women residents were significantly more likely to report lower self-efficacy for 9 of the 14 CLSE items (p < .0035). Mann-Whitney U and Fisher's exact tests showed there were no performance differences between men and women for successfully accessing the vein on the DHRT. Regression models relating performance and self-efficacy found no correlation for either gender. CONCLUSIONS: These results indicate that despite receiving the same SBT and performing at the same level, the gender-confidence gap exists in CVC SBT, and the Dunning-Kruger effect may also be evident.

[Venous air embolism following removal of central venous catheters: A case report].

Air embolism is a rare but dreaded complication of medical or surgical procedures with significant mortality. An abnormal air-to-blood pressure gradient and communication between the vein and atmosphere can lead to the venous air embolism. Here, we presented a rare case of venous air embolism just after the removal of the central venous catheters. A 59-year-old female was admitted to Peking University International Hospital suffering from neuromyelitis optica spectrum disorder. After 5 rounds of immunosorbent therapy, her hemodialysis catheter was removed. Five hours later, she suddenly experienced shortness of breath, dizziness, weakness of the lower extremities, transient loss of consciousness and seizures. Ultrasound showed a small amount of gas in the right internal jugular vein and brain CT showed scattered air accumulation in part of venous blood ducts and bilateral cavernous sinuses, which was diagnosed as air embolism. High-flow oxygen inhalation, compression of the right neck extubation site, head down and feet up left decubitus position, intravenous fluid therapy were used. The patient gradually improved and returned to normal activities after one week. To sum up, air embolism is a rare, but serious and life-threatening complication after central catheters removal. Clinicians need to be alerted and take appropriate preventive measures.

Iatrogenic Vertebral Arteriovenous Fistula Involving Brachiocephalic Vein Due to Central Venous Catheterization: A Case Report.

PURPOSE: To report a case of vertebral arteriovenous fistula (VAVF) caused by iatrogenic trauma of central venous catheterization (CVC) involving brachiocephalic vein (BCV). CASE REPORT: A 79-year-old female was referred for assessment of a vertebral artery (VA) aneurysm at the V1 segment. The patient had no signs other than a vascular murmur on the right neck and was diagnosed 20 years after undergoing CVC. Right vertebral angiography revealed a high-flow shunt from the V1 segment of the right VA and draining into the right BCV. The fistula had a single communication between a pseudoaneurysm and large varix. We diagnosed the patient with CVCinduced VAVF (CIVAVF) involving BCV and obliterated the shunt by selective transarterial and transvenous embolization of the pseudoaneurysm under flow control using a balloon catheter with no complications. CONCLUSION: This case highlights the point that CIVAVF involving BCV is rare but possible. In addition, there is a possibility that CIVAVF involving BCV does not demonstrate the findings of arterial steal or retrograde venous drainage and is undiagnosed for a long term due to lack of neurological manifestation and other subjective symptoms. We also showed that endovascular treatment can be feasible and useful for CIVAVF involving BCV.

Single-plane versus real-time biplane approaches for ultrasound-guided central venous catheterization in critical care patients: a randomized controlled trial.

BACKGROUND: Critical care patients often require central venous cannulation (CVC). We hypothesized that real-time biplane ultrasound-guided CVC would improve first-puncture success rate and reduce mechanical complications. The purpose of this study was to compare the success rate and safety of single-plane and real-time biplane approaches for ultrasound-guided CVC. METHODS: From October 2022 to March 2023, 256 participants with critical illness requiring CVC were randomized to either the single-plane (n = 128) or biplane (n = 128) ultrasound-guided cannulation groups. The success rate, number of punctures, procedure duration, incidence of catheterization-related complications, and confidence score of operators were documented. RESULTS: The central vein was successfully cannulated in all 256 participants (163 [64%] man and 93 [36%] women; mean age 69 ± 19 [range 13-104 years]), including 182 and 74 who underwent internal jugular vein cannulation (IJVC) and femoral vein cannulation (FVC), respectively. The incidence of successful puncture on the first attempt was higher in the biplane group than that in the single-plane group (91.6% vs. 74.7%; relative risk (RR), 1.226; 95% confidence interval (CI), 1.069-1.405; P = 0.002 for the IJVC and 90.9% vs. 68.3%; RR, 1.331; 95% CI, 1.053-1.684; P = 0.019 for the FVC). The biplane group was also associated with a higher first-puncture single-pass catheterization success rate (87.4% vs. 69.0% and 90.9% vs. 68.3%), fewer undesired punctures (1[1-1(1-2)] vs. 1[1-2(1-4)] and 1[1-1(1-3)] vs. 1[1-2(1-4)]), shorter cannulation time (205 s [162-283 (66-1,526)] vs. 311 s [243-401 (136-1,223)] and 228 s [193-306 (66-1,669)] vs. 340 s [246-499 (130-944)]), and fewer immediate complications (10.5% vs. 28.7% and 9.1% vs. 34.1%) for both IJVC and FVC (all P < 0.05). CONCLUSION: Real-time biplane imaging of ultrasound-guided CVCs offers advantages over the single-plane approach for critically ill patients. TRIAL REGISTRATION: This prospective RCT was registered at Chinese Clinical Trial Registry (ChiCTR2200064843). Registered 19 October 2022.

Diagnostic Value of Contrast-Enhanced Ultrasonography for Catheter-Related Right Brachiocephalic Vein and Superior Vena Cava Lesions in Patients Undergoing Hemodialysis-A Pilot Study.

OBJECTIVES: To evaluate the diagnostic efficacy of contrast-enhanced ultrasonography (CEUS) for detecting catheter-related right brachiocephalic vein (RBV) and superior vena cava (SVC) obstructions in patients undergoing hemodialysis (HD). METHODS: From June 1, 2021 to December 31, 2022, we enrolled 80 patients undergoing HD who had used or were using a central venous catheter as vascular access. We evaluated the diagnostic efficacy of conventional ultrasonography and CEUS for identifying RBV and SVC obstructions and compared them with that of digital subtraction angiography (DSA). In the stratified analysis, the SVC was divided into the upper and lower segments. In total, we analyzed 240 central venous segments, including the RBV. RESULTS: Among the RBV and SVC visualized by DSA, conventional ultrasonography and CEUS could visualize 67.92 and 100% of the vein segments, respectively; however, the lengths and diameters of the RBV and SVC were smaller than those recorded with DSA (P < .001). The diagnostic efficacy of CEUS for detecting catheter-related central venous obstruction was better than that of conventional ultrasonography, with a higher sensitivity (83.95 vs 41.98%), specificity (89.94 vs 53.46%), accuracy (87.92 vs 49.58%), and F1 score (82.42 vs 49.64%). CEUS showed good agreement (κ = 0.732) with DSA. In the stratified analyses, CEUS also showed higher sensitivity (83.93, 83.33, and 84.62%, respectively) and better agreement with DSA (κ = 0.635, 0.655, and 0.673, respectively) than conventional ultrasonography for detecting the RBV and the upper and lower segments of the SVC. CONCLUSIONS: CEUS had high sensitivity and specificity in diagnosing catheter-related RBV and SVC obstructions.

The value of transthoracic echocardiography and chest X-ray in locating the tip of central venous catheter in dialysis patients: a comparative study with computed tomography imaging.

To determine the tip position of the central venous catheter (CVC) in patients with dialysis, the guidelines recommend that it be determined using chest radiography (CXR) after catheterization, without fluoroscopy. However, some researchers have proposed that transthoracic echocardiography (TTE) can replace CXR, but this has not been widely adopted. This study aimed to determine which of the two aforementioned methods is more suitable for locating the tip position of the CVC. This prospective study included 160 patients who underwent hemodialysis at our hospital from March 2021 to December 2022. After inserting the CVC through the internal jugular vein, we used transthoracic echocardiography and CXR to determine the tip of the CVC and compared the results with those of computed tomography (CT). In the comparison between TTE and CXR for locating the CVC tip, we obtained three main findings. (1) TTE was associated with fewer misdiagnosed cases than CXR. (2) TTE provided higher sensitivity (similar sensitivity in position 2), specificity, positive/negative predictive values, and accuracy than CXR. (3) When comparing the receiver operating characteristic curves of TTE and CXR, the area under the curve (95% confidence interval) for the former was larger. Additionally, we made anatomical discoveries: the "hyperechoic triangle" recognized by TTE was equivalent to the entrance of the superior vena cava into the right atrium shown by transesophageal transthoracic echocardiography. TTE is more suitable than CXR as the first examination for CVC tip localization, as it improves diagnostic accuracy and reduces X-ray radiation damage.

Should Sedillot's triangle be used for central venous cannulation? A cadaveric study.

Central venous access remains an integral part of perioperative and intensive care, and several methods have been described to locate the internal jugular vein (IJV) prior to cannulation. The apex of Sedillot's triangle between the manubrial and clavicular heads of the sternocleidomastoid (SCM) muscle is a commonly used anatomical landmark for a central percutaneous approach to the IJV, but the literature highlights failures and complications when adopting this method. This cadaveric study was designed to investigate the usefulness of Sedillot's triangle to locate the IJV. Sixty-one cadavers were used for investigation at the University of Cambridge Human Anatomy Centre. Sedillot's triangle was dissected and a pin was inserted in a sagittal plane at the apex of the triangle. The location of the pin in relation to the IJV was recorded. The distance between the sternal and clavicular heads of SCM was also measured. In total, the pin inserted at the apex of Sedillot's triangle pierced the IJV in 72/117 (61.5%) of dissections, with 71.4% on the right and 52.5% on the left. There was important variation in SCM anatomy, and there was no gap between its two heads in 12% of the neck dissections. We demonstrate an overall poor success rate of the central percutaneous approach using Sedillot's triangle, although our findings are limited being a simulated cadaveric study. We support education and use of ultrasound in addition to landmark techniques to aid the safe insertion of central venous catheters.

Unexpected Tension Pneumothorax Developed during Anesthetic Induction Aggravated by Positive Pressure Ventilation: A Case Report.

Background and Objectives: Tension pneumothorax is a life-threatening emergency condition that requires immediate diagnosis and intervention. However, due to the non-specific symptoms and the rarity of its occurrence during surgery, anesthesiologists encounter difficulties in promptly diagnosing tension pneumothorax when it arises intraoperatively. Diagnosing tension pneumothorax can become even more challenging in unexpected situations in patients with normal preoperative evaluation for general anesthesia. Materials and Methods, Results: We report the case of a 66-year-old woman who underwent general anesthesia for oblique lateral interbody fusion surgery of her lumbar spine. Though she did not have any respiratory symptoms prior to the induction of anesthesia, auscultation following endotracheal intubation indicated decreased breathing sound in the left hemithorax of the chest. Subsequently, her vital signs showed tachycardia, hypotension, and hypoxemia, and the ventilator indicated a gradual increase in the airway pressure. We verified the proper depth of the endotracheal tube to exclude one-lung ventilation, and, in the meantime, learned that there had been unsuccessful attempts at left subclavian venous catheterization by the surgical department on the previous day. Tension pneumothorax was diagnosed through portable chest radiography in the operating room, and needle thoracostomy and chest tube insertion were performed immediately, which in turn stabilized her vital signs and airway pressure. The surgery was uneventful, and the chest tube was removed one week later after evaluation by the cardiothoracic department. The patient was discharged from hospital on postoperative day 14 without known complications. Conclusions: Anesthesiologists should be aware of the conditions and risk factors that may cause tension pneumothorax and remain vigilant for signs of its development throughout surgery, even for patients who show normal preoperative assessments. An undetected small pneumothorax without any symptoms can progress to tension pneumothorax through positive pressure ventilation during general anesthesia, posing a life-threatening situation. If a tension pneumothorax is highly suspected through clinical assessments, its prompt differentiation and timely diagnosis are crucial, allowing for rapid intervention to stabilize vital signs.

NECK HEMATOMA AFTER CENTRAL VENOUS CATHETERIZATION AND AWAKE INTUBATION AS RESCUE AIRWAY MANAGEMENT TECHNIQUE: A CASE REPORT.

Central venous catheterization (CVC) of the internal jugular vein is an invasive procedure commonly performed in anesthesiology practice. Usually it is an uneventful procedure but complications such as bleeding, infection, and potential damage to the surrounding structures can occur. One of the complications is neck hematoma, which can distort airway anatomy and cause upper airway obstruction. We present a patient who underwent endovascular mitral valve repairment procedure under general anesthesia. Accidental puncture of carotid artery occurred while attempting to place the central line. Later, during awakening in the coronary intensive care unit, the patient developed neck hematoma. The diagnosis was confirmed with multi-slice computed tomography (MSCT) and MSCT angiography showed active arterial blood extravasation. Despite it, the patient was extubated. Awake tracheal intubation (ATI) with video laryngoscopy was the technique of choice for reintubation because of the neck swelling and compression onto laryngeal structures. In this case, rushed extubation put the patient at risk. Video laryngoscopy ATI with appropriate preparation and titrated sedation can enable quick and safe rescue airway management in patients with rapidly developing neck hematoma, along with definitive evacuation and treatment.

Determination of the optimal length of insertion for central venous catheterization via axillary vein cannulation using preoperative chest X-ray- A prospective feasibility study.

Background and Aims: Ensuring safe central venous catheter tip placement is important. Multiple techniques are available to estimate the length of catheter insertion for subclavian and internal jugular approaches. However, the methods to determine the length of insertion for the axillary route have not been validated. The purpose of this feasibility study was to evaluate a simple method for the calculation of catheter length to be inserted and assess whether it accurately predicts the correct tip placement. Material and Methods: A total of 102 patients requiring preoperative central venous cannulation were evaluated, out of which 60 had successful axillary vein (AxV) cannulation. The length of insertion was calculated using the formula: (2/3* A + B) +Y (A: Clavicular length on chest radiograph [CXR], B: Vertical distance between the sternal head and carina on CXR, Y: Perpendicular distance from the skin to the AxV on ultrasound). A postoperative CXR was used to assess the accurate tip placement (2 cm above the carina to 0.5 cm below it). The primary outcome of the study was the rate of successful placement of the central venous catheter (CVC) in terms of the correct position of the tip of the catheter when the length of the catheter inserted was predicted by the formula described previously. Results: Optimal placement was observed in 83.33% of the cases. A higher rate of accuracy was seen in the females (P value = 0.03) and shorter patients (P value = 0.01). A Bland-Altman plot depicted a high degree of agreement. Conclusion: Use of the formula using a CXR and ultrasound allowed P successful placement of the CVC tip at the desired location in 83.33% of the cases.