SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: Subclavian vein

170

BACKGROUND: Takayasu arteritis is a large vessel vasculitis occurring in young females. We report a rare presentation of Takayasu arteritis in a Sri Lankan woman. She presented with bronchiectasis and left recurrent laryngeal nerve palsy prior to the onset of vascular symptoms. This case illustrates an atypical presentation of this disease and the diagnostic dilemma that the physician may be faced with. CASE PRESENTATION: A 39-year-old woman presented with chronic cough, haemoptysis and hoarseness of voice. She had left recurrent laryngeal nerve palsy and high inflammatory markers on investigation. CT thorax revealed aortic wall thickening and traction bronchiectasis. 2 D echocardiogram revealed grade 1 aortic regurgitation compatible with aortitis. She did not have weak peripheral pulses or a blood pressure discrepancy and did not meet American College of Rheumatology (ACR) criteria for diagnosis of Takayasu arteritis at this stage. Tuberculosis, syphilis and sarcoidosis was excluded. While awaiting angiography, she developed left arm claudication and a pericardial effusion. Angiography revealed evidence of Takayasu arteritis and absence of flow in the left subclavian artery. Takayasu arteritis was diagnosed at this stage after a period of eight months from the onset of initial symptoms. She is currently on prednisolone, azathioprine and aspirin. CONCLUSION: Bronchiectasis and recurrent laryngeal nerve palsy is a rare presentation of Takayasu arteritis. Atypical presentations can occur in Takayasu arteritis prior to the onset of vascular symptoms. Elevation of inflammatory markers are an early finding. A high degree of suspicion is needed to identify these patients in the early course of the disease.

Concepts: Cardiology, Common carotid artery, Brachiocephalic artery, Subclavian vein, Vertebral artery, Subclavian artery

28

A 36-year old woman presented with a 5-year history of progressive dysphagia. The barium swallow of the oesophagus revealed an oblique extrinsic defect consistent with an aberrant right subclavian artery. A computed tomography angiogram confirmed the diagnosis. Surgical correction is indicated for dysphagia lusoria in association with an aberrant right subclavian artery. The patient underwent surgical repair through the right supraclavicular approach, which provided a good exposure. We describe the use of this approach, which avoids the possible complications of thoracotomy or sternotomy in the surgical management of dysphagia lusoria.

Concepts: Medical imaging, Common carotid artery, Brachiocephalic artery, Subclavian vein, Vertebral artery, Subclavian artery, Aberrant subclavian artery

28

OBJECTIVE: The axillary vein is an easily accessible vessel that can be used for ultrasound-guided central vascular access and offers an alternative to the internal jugular and subclavian veins. The objective of this study was to identify which transducer orientation, longitudinal or transverse, is better for imaging the axillary vein with ultrasound. METHODS: Emergency medicine physicians at an inner-city academic medical center were asked to cannulate the axillary vein in a torso phantom model. They were randomized to start with either the longitudinal or transverse approach and completed both sequentially. Participants answered questionnaires before and after the cannulation attempts. Measurements were taken regarding time to completion, success, skin punctures, needle redirections, and complications. RESULTS: Fifty-seven operators with a median experience of 85 ultrasound procedures (interquartile range, 26-120) participated. The frequency of first-attempt success was 39 (0.69) of 57 for the longitudinal method and 21 (0.37) of 57 for the transverse method (difference, 0.32; 95% confidence interval [CI], 0.12-0.51 [P = .001]); this difference was similar regardless of operator experience. The longitudinal method was associated with fewer redirections (difference, 1.8; 95% CI, 0.8-2.7 [P = .0002]) and skin punctures (difference, 0.3; 95% CI, -2 to +0.7 [P = .07]). Arterial puncture occurred in 2 of 57 longitudinal and 7 of 57 transverse attempts; no pleural punctures occurred. For successful attempts, the time spent was 24 seconds less for the longitudinal method (95% CI, 3-45 [P = .02]). CONCLUSIONS: The longitudinal method of visualizing the axillary vein during ultrasound-guided venous access is associated with greater first-attempt success, fewer needle redirections, and a trend of fewer arterial punctures compared with the transverse orientation.

Concepts: Blood vessel, Artery, Vein, Internal jugular vein, Subclavian vein, Subclavian artery, Axillary vein

28

Aberrant right subclavian artery (ARSA) is an uncommon congenital anomaly that often becomes aneurysmal. The ARSAs are often asymptomatic but aneurysms arising in this location are potentially lethal. Due to the high morbidity and mortality rates associated with the traditional open repair methods, less invasive endovascular methods are becoming more popular. This is a case describing a unique hybrid repair of an aneurysmal ARSA in an asymptomatic male.

Concepts: Common carotid artery, Brachiocephalic artery, Subclavian vein, Vertebral artery, Subclavian artery, Aberrant subclavian artery

27

Snake bites are leading causes of morbidity and mortality worldwide, especially in rural areas. Therapeutic plasma exchange has been used in the treatment of many different conditions such as immunologic diseases, toxicologic disorders, and snake envenomation. The aim of this study is to evaluate the efficacy of plasma exchange treatment on clinical status, outcomes, and discharge of patients who were bitten by venomous snakes. The study was conducted retrospectively in the Emergency Department of Gaziantep University from January 2002 to December 2011. Thirty-seven patients were included in the present study. Routine biochemical and hematologic laboratory parameters were studied before and after plasma exchange. Demographic data, clinical status, and outcomes of patients were recorded. Plasma exchange was performed by using centrifugation technology via an intravenous antecubital or subclavian vein catheter access. Human albumin/fresh frozen plasma was used as replacement fluids. A significant correlation was seen between therapeutic plasma exchange and improvement of laboratory results. None of the study patients lost their limbs. Eight patients were sent to the intensive care unit. The mean length of the hospital stay was 12.2days (4-28). All patients were discharged with good recovery. No complications were seen during the 3months following discharge. Plasma exchange appears to be an effective treatment intervention for snake bite envenomations, especially in the management of hematologic problems and in limb preservation/salvage strategies. In addition to traditional treatment methods, plasma exchange should be considered by emergency physicians in cases of snake bite envenomation as a therapeutic approach to facilitate rapid improvement.

Concepts: Medicine, Hospital, Central venous catheter, Subclavian vein, Snakebite, Viperidae, Snake, Bite

26

Different methods for venous access are used for permanent pacemaker or implantable cardioverter defibrillator (ICD), of which subclavian vein puncture technique is the most widely practised. Although this approach is relatively easy to learn, quick and offers high success rates, it may be associated with potential serious acute complications including pneumothorax, emopneumothorax, brachial plexus injury and longer-term complications such as lead fracture, loss of lead insulation and subclavian crush syndrome especially in young patients with ICD leads. Axillary vein approach seems to be a favourable technique not only for the prevention of acute complications but also to reduce lead failure including lead insulation and lead fracture prevention with a consequently better long-term lead survival compared with the classical subclavian approach. Although randomized studies are lacking, recent reports not only evaluated the safety and effectiveness of new fluoroscopic axillary venous puncture technique, but also compared it with the conventional intrathoracic subclavian venous puncture technique for the implantation of leads in permanent pacing. Various techniques of axillary vein puncture have been proposed ranging from a blind percutaneous puncture to the use of different tools such as contrast venography and ultrasound. In this article, we report a case of subclavian crush syndrome, the use of a modified Bellot’s technique of axillary vein puncture that we currently use and the potential benefits of axillary vein puncture for pacemaker and ICD leads implantation compared with subclavian approach to avoid acute and long-term lead complications.

Concepts: Implantable cardioverter-defibrillator, Magnetic resonance imaging, Subclavian vein, Artificial pacemaker, Brachial plexus, Subclavian artery, Axillary artery, Axillary vein

4

Although ultrasound guidance for subclavian vein catheterization has been well described, evidence for its use has not been comprehensively appraised. Thus, we conducted a systematic review and metaanalysis to determine whether ultrasound guidance of subclavian vein catheterization reduces catheterization failures and adverse events compared to the traditional “blind” landmark method. All forms of ultrasound were included (dynamic 2D ultrasound, static 2D ultrasound, and Doppler).

Concepts: Evidence-based medicine, Systematic review, Central venous catheter, Meta-analysis, Subclavian vein, Subclavian artery

3

1

The primary objective was to estimate the prevalence of aberrant right subclavian artery (ARSA) in fetuses with Down syndrome. Secondary objectives were to assess the prevalence of ARSA in euploid fetuses, the feasibility of ultrasound evaluation of the right subclavian artery (RSA) in the first and second trimesters of pregnancy, the performance of ARSA in screening for trisomy 21 and its association with other abnormalities.

Concepts: Common carotid artery, Brachiocephalic artery, Down syndrome, Subclavian vein, Vertebral artery, Subclavian artery, Aberrant subclavian artery

1

The objective of this prospective, randomised study was to examine the impact of a multi-angle needle guide for ultrasound-guided, in-plane, central venous catheter placement in the subclavian vein. One hundred and sixty patients were randomly allocated to two groups, freehand or needle-guided, and then 159 catheterisations were analysed. Cannulation of the first examined access site was successful in 96.9% of cases with no significant difference between groups. There were three arterial punctures and no other severe injuries. Catheter misplacements did not differ between the groups. Higher success rates within the first and second attempts in the needle-guided group were observed (p = 0.041 and p = 0.019, respectively). Use of the needle guide reduced the access time from a median (IQR [range]) of 30 (18-76 [6-1409]) s to 16 (10-30 [4-295]) s; p = 0.0001, and increased needle visibility from 31.8% (9.7%-52.2% [0-96.67]) to 86.2% (62.5%-100% [0-100]); p < 0.0001. A multi-angle needle guide significantly improved aligning the needle and ultrasound plane compared with the freehand technique when cannulating the subclavian vein. Use of the guide resulted in faster access times and increased success at the first and second attempts.

Concepts: Blood, Artery, Vein, Internal jugular vein, Central venous catheter, Subclavian vein, Catheter, Peripheral venous catheter