Percutaneous Central Venous Access for Resuscitation in Trauma

Objective: To determine the safety of percutaneous central venous access when used for trauma resuscitation and whether the initial hemodynamic status of the patient or the site of placement affects the ease or success of line placement. Methods: Consecutive major-trauma patients were managed using a resuscitation protocol guiding intravenous line use. Percutaneous peripheral venous access was initially attempted in all patients. If this approach was unsuccessful or proved to be inadequate for volume resuscitation, venous access was attempted using central venous catheter-introducer sets. The site of the central venous access was determined by protocol. For thoracic injury, access was via the ipsilateral subclavian vein (SCV), the ipsilateral internal jugular vein (IJV), or the femoral vein. For suspected mediastinal injury, access was via the contralateral SCV or IJV, or the femoral vein. For abdominal or flank injury, access was via the SCV or IJV only. Multiple central venous access sites were used at the discretion of the trauma team. Results: Central venous access was successful at 144 of 147 sites (99%) used in 122 patients during the study period. There was only one major complication (rate = 0.7%; 95% CI 0.0–3.8%). Mean catheter placement time was 1.9 minutes, and cannulation occurred with a mean of 1.8 needle passes. Most patients (81/122) were hypotensive (blood pressure ≤90 torr) at the time of line placement, including 44 who were in cardiac arrest and four awake patients who had no obtainable blood pressure. Neither the access site nor the presence of hypotension was associated with the mean time to obtain central venous access, the mean number of attempts, or the complication rate. Conclusion: Percutaneous central venous access is relatively safe and reliable for gaining intravenous access when resuscitating trauma patients, when used in a center where physicians are experienced in the technique. Consideration should be given to expanding the use of central venous access in trauma resuscitation.     

Assessment of a New Model for Femoral Ultrasound-guided Central Venous Access Procedural Training: A Pilot Study

Objectives: Repetitive practice with feedback in residency training is essential in the development of procedural competency. Lightly embalmed cadaver laboratories provide excellent simulation models for a variety of procedures, but to the best of our knowledge, none describe a central venous access model that includes the key psychomotor feedback elements for the procedure, namely intravascular contents that allow for determination of correct needle position by either ultrasonographic imaging and/or aspiration or vascular contents. Methods: A cadaver was lightly embalmed using a technique that preserves tissue texture and elasticity. We then performed popliteal fossa dissections exposing the popliteal artery and vein. Vessels were ligated distally, and 14‐gauge catheters were introduced into the lumen of each artery and vein. The popliteal artery and vein were then infused with 200 mL of icterine/gel and 200 mL of methylene blue/gel, respectively. Physician evaluators then performed ultrasound (US)‐guided femoral central venous line placements and rated the key psychomotor elements on a five‐point Likert scale. Results: The physician evaluators reported a median of 10.5 years of clinical emergency medicine (EM) experience with an interquartile range (IQR) of 16 and a median of 10 central lines placed annually (IQR = 10). Physician evaluators rated the key psychomotor elements of the simulated procedure as follows: ultrasonographic image of vascular elements, 4 (IQR = 0); needle penetration of skin, 4.5 (IQR = 1); needle penetration of vein, 5 (IQR = 1); US image of needle penetrating vein, 4 (IQR = 2); aspiration of vein contents, 3 (IQR = 2); passage of dilator into vein, 4 (IQR = 2); insertion of central venous catheter, 5 (IQR = 1); US image of catheter insertion into vein, 5 (IQR = 1); and overall psychomotor feedback of the simulated procedure compared to the evaluators’ actual patient experience, 4 (IQR = 1). Conclusions: For the key psychomotor elements of central venous access, the lightly embalmed cadaver with intravascular water‐soluble gel infusion provided a procedural model that closely simulated clinicians’ experience with patients. ACADEMIC EMERGENCY MEDICINE 2010; 17:88–92 © 2009 by the Society for Academic Emergency Medicine     

Use of Echocardiography to Identify Appropriate Placement of a Central Venous Catheter Wire in the Vena Cava Prior to Cannulation

Ultrasound guidance is now the standard of care when placing a central venous catheter (CVC), resulting in decreased complications and increased first‐pass success rates. However, even with ultrasound guidance being used for the initial venipuncture, misplacement of a CVC in either an unwanted vein or in an artery still occurs. Here, we discuss a simple technique to assist in the adequate placement of the CVC in the vena cava using bedside echocardiography.     

Evaluation of Central Venous Access with Accelerated Seldinger Technique Versus Modified Seldinger Technique

Background

Central vein catheter (CVC) placement using the modified Seldinger technique is a common procedure in the emergency department, but can be time consuming due to the multiple pieces of equipment included in central line kits and the number of steps in the procedure. Preassembled devices combine a needle, guidewire, dilator, and sheath into one unit and potentially simplify the process and reduce time required for CVC placement using the accelerated Seldinger technique.

Video Analysis of Accidental Arterial Cannulation With Dynamic Ultrasound Guidance for Central Venous Access

Objective. Accidental arterial cannulation during ultrasound‐guided central venous cannulation is rarely reported and should be much less likely with dynamic guidance. Although accidental arterial penetration with the needle may occur periodically without notice and with little harm, actual arterial dilation and line placement may result in serious complications. Methods. This series reports 6 such cases of accidental arterial cannulation and central line insertion under dynamic ultrasound guidance. Results. Two of the arterial cannulations resulted in airway loss, with 1 of these ending in death. The remaining 4 arterial lines led to serious local complications. Ultrasound video analysis of each line placement or postplacement analysis was reviewed, and common pitfalls were extracted. In 3 cases, a central line went directly through the internal jugular vein (IJ) and into the carotid artery. In 1 case, a cordis introducer sheath traveled through the posterior wall of the common femoral vein and into the deep femoral artery branch below. Each patient was hypotensive and hypoxic, making traditional safety checkpoints such as aspiration of bright red blood and pulsatile flow from the syringe hub less reliable in identifying accidental arterial cannulation. All ultrasound‐guided cannulations were performed by a standard short‐axis approach with high‐resolution linear array ultrasound transducers on modern equipment. Conclusions. The short‐axis approach, as seen in this series, can provide a false sense of security to the practitioner and allows for potentially dangerous accidental arterial cannulation. In the setting of critically ill patients, it may be prudent to not only visualize the entire path of the needle with the long‐axis approach but also confirm correct cannulation by tracing the guide wire in the long axis before line placement.     

Effects of Analgesic Use on Inflammation and Hematology in a Murine Model of Venous Thrombosis

Venous thrombosis (VT) is a significant cause of morbidity and mortality in humans. Surgical animal models are crucial in studies investigating the pathogenesis of this disease and evaluating VT therapies. Because inflammation is critical to both the development and resolution of VT, analgesic medications have the potential to adversely affect multiple parameters of interest in VT research. The objective of this study was to determine how several common analgesics affect key variables in a murine ligation model of deep vein thrombosis. Male C57BL/6 mice were randomly assigned to receive either local (bupivacaine) or systemic parenteral analgesia (buprenorphine, tramadol, or carprofen) or 0.9% NaCl (control). All mice underwent laparotomy and ligation of the inferior vena cava, and treatment was continued until euthanasia at 6 or 48 h after surgery. Analysis of harvested tissues and blood included: hematology, thrombus weight, serum and vein-wall cytokines (IL1β, IL6, IL10, TNFα), soluble P-selectin, and vein-wall leukocyte infiltration. Compared with 0.9% NaCl, all of the analgesics affected multiple parameters important to VT research. Carprofen and tramadol affected the most parameters and should not be used in murine models of VT. Although they affected fewer parameters, a single dose of bupivacaine increased thrombus weight at 6 h, and buprenorphine was associated with reduced vein wall macrophages at 48 h. Although we cannot recommend the use of any of the evaluated analgesic dosages in this mouse model of VT, buprenorphine merits additional investigation to ensure the highest level of laboratory animal care and welfare.Abbreviations: hpf, high-power field; IVC, inferior vena cava; IQR, interquartile range; sP-sel, soluble P-selectin; TW, thrombus weight; VT, venous thrombosisVenous thrombosis (VT) is among the most common vascular diseases and is a significant cause of morbidity and mortality in humans. Numerous risk factors have been identified including advanced age,⁴² neoplasia,⁵⁰ and obesity,¹ and approximately 275,000 new cases are diagnosed annually in the United States alone, with a recurrence rate of approximately 30%.²⁰ Historically, the primary contributors toward the development of VT have been summarized as the Virchow Triad and include hypercoagulability, endothelial injury, and vascular stasis.⁴⁵ During the last 4 decades, additional attention has been paid to the role that inflammation plays in the initiation, progression, and eventual resolution of VT, emphasizing endothelial cellular and molecular interactions.⁴⁷ It is now understood that the endothelium plays a key role in maintaining an antithrombotic, vasodilatory state, in part through the production of nitric oxide and IL10, an antiinflammatory cytokine.⁵ After endothelial dysfunction, induced by either direct physical trauma or secondary to systemic proinflammatory conditions, a cascade of changes occurs that fosters a prothrombotic, vasoconstrictive environment. In particular, for VT, the upregulation of cell adhesion molecules like P-selectin on the endothelium lead to the adhesion of activated platelets and leukocytes, contributing to thrombus formation and inflammation. Leukocyte migration across the vascular wall, particularly by polymorphonuclear cells, further contributes to early endothelial injury. Over time, these same cells, acting in concert with monocytes, are important for effective postthrombosis remodeling and eventual resolution.^33,40,47As the underlying mechanisms of thrombus formation have been elucidated and novel antithrombotic therapies have been developed in response, animal models have played an ever increasing role in both basic and applied VT research.²⁷ Although no single species perfectly recapitulates the human disease, and both rodent and nonrodent large animal models are important to the study of VT, murine models serve a crucial role in understanding the mechanisms of VT and evaluating novel therapies headed for clinical trials.^34,44 Characterizing the effects of medications, such as analgesics, on these models is an important aspect of model refinement, particularly when the model has a surgical component.Because of the difficulties in initiating thrombus formation, most models currently used in VT research involve some degree of surgical invasiveness to access the vessel endothelium or to induce partial stasis. Because of the limited utility of minimally invasive methods due to their small body size, the absence of spontaneously occurring disease, and the need to induce thrombus formation in larger vessels, rodents generally require more invasive surgical manipulation than do some large animal models. Although all rodent models used to study VT involve some degree of surgical intervention, only 2 techniques have been shown to produce consistent, reproducible thrombus formation with minimal postoperative mortality, the electrolytic injury model¹² and ligation of the inferior vena cava⁴⁹ (IVC), both of which require laparotomy. Consistent with the Guide for the Care and Use of Laboratory Animals,²⁴ PHS policy,³⁵ and the Animal Welfare Act,³ these surgical models warrant the use of analgesia to minimize postoperative discomfort and distress unless there is compelling scientific justification for the omission of pain-relieving medication. Historically, the use of analgesics has been questioned in several laparotomy models of diseases in which inflammation plays a significant role, including sepsis and VT. The justification for withholding analgesics in these scenarios may reflect concerns that these compounds alter inflammation, immune function, and coagulation and thereby introduce a confounding experimental variable.Although these are valid and important considerations in preserving the integrity of study results, generalizations about an individual drug may ignore the variability seen among compounds within the same analgesic class.³⁹ The routine clinical use of analgesics in human patients afflicted with these conditions further complicates the ethical dilemma when weighing the evidence against analgesic administration in laboratory species. Despite the widespread use of animal surgical models in VT research, very few species-specific data regarding the effects of analgesia on inflammation and thrombus formation are currently available in the literature, particularly in regard to the most commonly used VT surgical models. This type of work, as it relates to analgesic use in various species and specific models with a high potential for pain and distress, is crucial if IACUC and investigators are to ensure ethical care without compromise of study data. The current study characterized the effects of 4 analgesics with varied mechanisms of action on specific endpoints of the commonly used mouse IVC ligation model of deep vein thrombosis and compared these findings with data from other species and models in the published literature.     

经外周静脉穿刺中心静脉置管与植入式静脉输液港在化疗患者中应用效果的系统评价

目的 系统评价经外周静脉穿刺中心静脉置管(peripherally inserted central catheter,PICC)与植入式静脉输液港(venous port access,VPA)两种中心静脉置管方式在化疗患者治疗中应用的差异。方法 全面检索Cochrane、JBI、PubMed、EMBASE、CINAHL、CBM、维普等数据库,收集所有讨论PICC与VPA对化疗患者应用效果的随机对照试验(randomized controlled trial,RCT)、受控的临床试验(controlled clinical trial,CCT)和队列研究,按照JBI文献评价标准对文献进行质量评价,使用RevMan 5.3进行Meta分析或描述性分析。结果 共纳入13篇文献。研究结果显示PICC导管留置时间低于VPA(RR:9.06,95%CI:5.82~14.09);PICC一次性置管成功率高于VPA,但其差别无统计学意义(RR:0.97,95%CI:0.92~1.03),P0.05;PICC并发症发生率大于VPA(RR:0.30,95%CI:0.22~0.41),P0.05;描述性分析显示VPA组生活质量优于PICC组,且留置时间大于1年时,VPA的总费用低于PICC。结论 VPA与PICC相比,并发症发生率低,留置时间长,患者生活质量高,且维护成本相对较低。但由于高质量文献较少,仍需进一步论证研究。     

Transvenous Removal of an Entangled Central Venous Line Following Complex Cardiac Surgery

Unintended internal suturing of central venous lines or pulmonary artery catheters in the superior caval vein or the right atrium following cardiac surgery remains a rare but troublesome complication. The line is normally entangled in safety or hemostasis sutures after the removal of the superior caval cannulation. If mild tension is unsuccessful, the patient normally undergoes resternotomy. The objective of this brief communication is to describe of a simple and safe removal method using a transvenous rotational cutting device to divide the hemostasis suture. In order to avoid complicating bleeding, a time delay between initial placement and removal is highly recommended. For extraction, a fully equipped cardiovascular operating room with central venous and arterial lines, attached defibrillator pads, transesophageal echo monitoring, fluoroscopy, and a surgical team, including a heart and lung machine and a perfusionist standby, is mandatory.     

高频超声引导经锁骨下静脉中心静脉置管术的临床应用价值

临床推广应用.     

Predicting Peripheral Venous Access Difficulty in the Emergency Department Using Body Mass Index and a Clinical Evaluation of Venous Accessibility

Background

Peripheral venous (PV) cannulation, one of the most common technical procedures in Emergency Medicine, may prove challenging, even to experienced Emergency Department (ED) staff. Morbid obesity (body mass index [BMI] ≥ 40) has been reported as a risk factor for PV access failure in the operating room.

Objectives

We investigated PV access difficulty in the ED, across BMI categories, focusing on patient-related predicting factors.

Methods

Prospective, observational study including adult patients requiring PV lines. Operators were skilled nurses and physicians. PV accessibility was clinically evaluated before all cannulation attempts, using vein visibility and palpability. Patient and PV placement characteristics were recorded. Primary outcome was failure at first attempt. Outcome frequency and comparisons between groups were examined. Predictors of difficult cannulation were explored using logistic regression. A p-value <0.05 was considered significant.

Results

PV lines were placed in 563 consecutive patients (53 ± 23 years, BMI: 26 ± 7 kg/m²), with a success rate of 98.6%, and a mean attempt of 1.3 ± 0.7 (range 1–7). Failure at the first attempt was recorded in 21% of patients (95% confidence interval [CI] 17.6–24.4). Independent risk factors were: a BMI ≥ 30 (odds ratio [OR] 1.98, 95% CI 1.09–3.60), a BMI < 18.5 (OR 2.24; 95% CI 1.07–4.66), an unfavorable (OR 1.66, 95% CI 1.02–2.69), and very unfavorable clinical assessment of PV accessibility (OR 2.38, 95% CI 1.15–4.93).

Conclusion

Obesity, underweight, an unfavorable, and a very unfavorable clinical evaluation of PV accessibility are independent risk factors for difficult PV access. Early recognition of patients at risk could help in planning alternative approaches for achieving rapid PV access.     

A Model for Increasing Access to Preexposure Prophylaxis (PrEP) Services in the Substance Use Population

In 2017, a low-resource substance use treatment center in Baltimore, Maryland, noted that at least 38% of patients, ranging from 18 to 76 years old, with substance use disorders (SUD) met the criteria for preexposure prophylaxis (PrEP) therapy. PrEP therapy consists of a daily medication to prevent transmission of human immunodeficiency virus. A conceptual framework model was developed linking eligible patients with SUD to PrEP services based on current Centers for Disease Control and Prevention PrEP recommendations. Three tools were developed for PrEP service planning, implementation, and evaluation. The focus of this report is to increase access to and uptake of comprehensive PrEP services in those with SUD who are at risk for acquiring human immunodeficiency virus.     

Central Venous Catheter Rupture in a Pediatric Patient: A Case Study

Thorough assessment of a central venous catheter (CVC) is essential before use in radiology to prevent infiltration or extravasation of fluids, medications, and contrast media. Although rare, reports of pain during injection of an established and properly positioned CVC can be a critical finding associated with catheter rupture. Early identification is necessary to reduce potential harm to the patient.