Maurizio Cariati

Percutaneous ultrasound-guided central venous catheters: the lateral in-plane technique for internal jugular vein access

Purpose To describe the possible ultrasound guidance techniques for the insertion of central venous catheters (CVCs), with emphasis particularly to the lateral short axis in-plane technique. Methods Numerous articles have shown significant benefits of using ultrasound guidance for venous access. Two main approaches to vein puncture are available, when considering visualization of the needle during its entry into the vein under the ultrasound beam: in-plane and out-of-plane, which can be combined with two types of vein visualization, placing the ultrasound probe on the vein long axis or short axis. Results Advantages and limitations in internal jugular vein (IJV) cannulation for long-term dialysis CVCs are described for the above-mentioned approaches and visualizations. The lateral short axis in-plane technique has virtually no limitations, ensuring most benefits. Conclusions The lateral short axis in-plane technique should be considered the first-line technique for IJV cannulation.

Optimization of dialysis catheter function

Central venous catheters (CVCs) are essential in the management of hemodialysis patients, but they also carry unintended negative consequences and in particular thrombosis and infection, adversely affecting patient morbidity and mortality. This review will focus on the etiology, prevention, and management of CVC-related dysfunction, which is mainly associated with inadequate blood flow. CVC dysfunction is a major cause of inadequate depuration. Thrombus, intraluminal and extrinsic, as well as fibrous connective tissue sheath (traditionally indicated as fibrin sheath) formation play a central role in establishing CVC dysfunction. Thrombolysis with urokinase or recombinant tissue plasminogen activator (rTPA) can be undertaken in the dialysis unit, restoring adequate blood flow in most patients, preserving the existing catheter, and avoiding an interventional procedure. If thrombolytics fail, mainly because of the presence of fibrous connective tissue sheath, catheter exchange with fibrin sheath disruption may be successful and preserve the venous access site. Prevention of CVC dysfunction is important for containing costly pharmacologic and interventional treatments, which also affect patients’ quality of life. Prevention is based on the use of anticoagulant and/or thrombolytic CVC locks, which are only partially effective. Chronic oral anticoagulation with warfarin has also been proposed, but its use for this indication is controversial and its overall risk-benefit profile has not been clearly established.

Congenital anomalies of superior vena cava and their implications in central venous catheterization

Congenital anomalies of superior vena cava (SVC) are generally discovered incidentally during central venous catheter (CVC) insertion, pacemaker electrode placement, and cardiopulmonary bypass surgery. Persistent left SVC (PLSVC) is a rare (0.3%) anomaly in healthy subjects, usually asymptomatic, but when present and undiagnosed, it may be associated with difficulties and complications of CVC placement. In individuals with congenital heart anomalies, its prevalence may be up to 10 times higher than in the general population. In this perspective, awareness of the importance of the incidental finding of PLSV during CVC placement is crucial. To improve knowledge of this rare but potentially dangerous condition, we describe the embryological origin of SVC, its normal anatomy, and possible congenital anomalies of the venous system and of the heart, including the presence of a right to left cardiac shunt. Diagnosis of PLSVC as well as the clinical complications and technical impact of SVC congenital anomalies for CVC placement are emphasized.

Trans-thoracic biopsy of lung lesions: FNAB or CNB? Our experience and review of the literature

PurposeThis study was performed to determine the type and incidence of complications of fine-needle aspiration biopsy (FNAB) and core biopsy (CNB) performed under computed tomography (CT) guidance to characterise lung lesions, and assess the diagnostic accuracy of the two techniques.Materials and methodsIn 2009–2011, we performed 124 lung biopsies (66 CNB and 56 FNAB) on 121 patients with a mean age of 72.4xa0years. Exclusion criteria were pulmonary resection, pleural lesions and/or effusions, and inadequate blood-coagulation profile. All examinations were acquired after contrast-agent administration in a craniocaudal direction from the lung apex to base during a single inspiratory breath-hold, with standardised parameters. Each lesion was scanned with 13–15 slices that could be repeated whenever necessary to document the needle track and for lesion centring, by positioning a metallic marker perpendicular to the centring light to indicate the point of needle access. Unless otherwise clinically indicated, 4xa0h after the procedure chest radiography was performed.ResultsAge was found to be a factor influencing the complications: pneumothorax in young subjects (31xa0%) and parenchymal haemorrhage in the elderly (30xa0%), with CNB but not with FNAB. We had more complications with the right lung: 50xa0% of pneumothorax cases in the upper lobe with CNB and 40xa0% of cases of haemorrhage in the lower lobe with FNAB. The anterior approach gave rise to more complications with CNB, while the posterior approach with FNAB. CNB had more complications than FNAB for lesions ≤3.5xa0cm (31 vs. 18xa0% pneumothorax), and >3.5xa0cm (34 vs. 9xa0% haemorrhage). There was no significant correlation with lesion histology, needle calibre or number of passes (probably due to the small number of procedures done with needles other than 18xa0G in CNB or 22xa0G in FNAB or involving more than one needle pass). The diagnostic accuracy of FNAB, done with a pathologist’s extemporaneous assessment of sample adequacy, was 94.83xa0% against 81.82.xa0% of CNB.ConclusionsFNAB under CT guidance is subject to a lower rate of complications and, if performed in the presence of the pathologist, has a greater diagnostic accuracy compared to CNB.

Tunneled central venous catheter exchange: techniques to improve prevention of air embolism

Malfunctioning tunneled hemodialysis central venous catheters (CVCs), because of thrombotic or infectious complications, are frequently exchanged. During the CVC exchanging procedure, there are several possible technical complications, as in first insertion, including air embolism. Prevention remains the key to the management of air embolism. Herein, we emphasize the technical tricks capable of reducing the risk of air embolism in long-term CVC exchange. In particular, adoption of a 5 to 10 degrees Trendelenburg position, direct puncture of the previous CVC venous lumen for guide-wire insertion, as opposed to guide-wire introduction after cutting the CVC, a light manual compression of the internal jugular vein venotomy site after catheter removal. The Valsalva maneuvre in collaborating patients, valved introducers, and correction of hypovolemia are also useful precautions. Principles of air embolism diagnosis and treatment are also outlined in the article.

Migraine with aura and white matter lesions: an MRI study

Several studies report the presence of white matter lesions on brain magnetic resonance imaging in patients with migraine. The aim of our study was to detect the entity of white matter T2-hyperintensities in 90 high selected patients affected by migraine with aura, compared to a group of 90 healthy controls. We found no significant difference of incidence of white matter alterations comparing these two groups.

Bladder cancer diagnosis: the role of CT urography.

Aims and Background To evaluate the diagnostic performance of computed tomography urography (CTU), we first compared it with cystoscopy and subsequently analyzed which CTU phase of acquisition has the highest diagnostic accuracy in identifying bladder cancer. Methods In 2013, 177 patients underwent both cystoscopy and CTU. For all acquisition phases, we calculated sensitivity, specificity, diagnostic accuracy, and positive and negative predictive value (PPV and NPV, respectively). We also evaluated the Cohen K coefficient. Results Computed tomography urography sensitivity, specificity, diagnostic accuracy, PPV, and NPV were as follows: 96.3%, 86.4%, 92.8%, 92.9%, and 92.7%; concordance calculated with Cohen K was good: 0.8413. The arterial acquisition phase showed the highest diagnostic accuracy, identifying 93.4% of all lesions. Conclusions Computed tomography urography is an accurate examination for the diagnosis of bladder cancer, and the arterial acquisition phase provides the best diagnostic information.

Placement of port-a-cath through the right internal jugular vein under ultrasound guidance

PurposeThis study was undertaken to demonstrate the effectiveness of ultrasound (US)-guided placement of porta-cath (PC) through the right internal jugular vein (RIJV) by evaluating the onset of early and late complications.Materials and methodsFrom 30 June 2008 to 30 June 2011, we placed 695 port-a-caths in 694 patients with a mean age of 58 years. Exclusion criteria were active infection, bleeding disorders and life expectancy <6 months. The procedures were performed in the angiography suite under local anaesthesia. After US-guided puncture of the RIJV, the subcutaneous pocket was prepared, followed by tunnelling of the vein and closure of the surgical wound. In order to evaluate pneumothorax (PNX), all patients underwent chest X-ray a few hours after the end of the procedure unless there were clinical indications. We evaluated the technical success of the procedure and the rate of complications.ResultsTechnical success was achieved in all cases. The device was kept in place for an average of 168 days. There was one case of PNX (0.14%) as shown on chest X-ray and five cases of late complications (0.70%): one case of intracatheter thrombosis (0.14%), two cases of disconnection between the reservoir and catheter (0.28%) and two cases of PC infection (0.28%).ConclusionsThis procedure incurs very small number of complications compared with other positioning techniques using accesses such as the subclavian vein. Complications recorded in our study are comparable, in type and incidence, to those found by other authors, with the most frequent being device infection.RiassuntoObiettivoScopo del presente lavoro è stato dimostrare l’efficacia del posizionamento di port-a-cath (PC) attraverso la vena giugulare interna destra (VGID) sotto guida ecografica (US) valutando l’insorgenza di complicanze.Materiali e metodiDal 30 giugno 2008 al 30 giugno 2011 abbiamo posizionato 695 PC in 694 pazienti con età media di 58 anni. I criteri di esclusione sono: infezione in atto, coagulopatie e aspettativa di vita inferiore ai 6 mesi. Le procedure sono state eseguite in sala angiografica previa anestesia locale. Abbiamo effettuato la puntura sottoguida US delle VGID, poi è stata preparata la tasca sottocutanea e tunnelizzazione del tramite e chiusura della ferita chirurgica. Per valutare lo pneumotorace (PNX) abbiamo eseguito un radiogramma del torace dopo qualche ora dalla procedura salvo diversa indicazione clinica. Abbiamo valutato la riuscita della procedura e il tasso di complicanze.RisultatiLa riuscita tecnica dell’impianto è stata ottenuta nella totalità dei casi. Il dispositivo è stato mantenuto in sede per una media di 168 giorni/paziente. Abbiamo registrato uno PNX (0,14%) evidenziato all’Rx di controllo e 5 casi di complicanze tardive (0,70%): 1 caso di trombosi intra-catetere (0,14%), 2 casi di deconnessioni tra il reservoir ed il catetere (0,28%) e 2 casi di infezioni del port (0,28%).ConclusioniLe complicanze che abbiamo osservato sono paragonabili sia in termini di incidenza che di tipologia a quelle riscontrate da altri autori; infatti anche dal nostro studio emerge che l’infezione del dispositivo risulta essere la complicanza più frequente.

Response to: Central venous catheterization in fragile patients: which is the best approach?

1. Pescatori LC, Carrafiello G. Central venous catheterization in fragile patients: which is the best approach? J Vasc Access. 2017;18(2):e24. 2. Rossi UG, Rigamonti P, Tichà V, et al. Percutaneous ultrasoundguided central venous catheters: the lateral in-plane technique for internal jugular vein access. J Vasc Access. 2014;15(1):56-60. 3. Rossi UG, Rigamonti P, Torcia P, et al. Congenital anomalies of superior vena cava and their implications in central venous catheterization. J Vasc Access. 2015;16(4):265-268. 4. Gallieni M, Giordano A, Rossi U, Cariati M. Optimization of dialysis catheter function. J Vasc Access. 2016;17(Suppl 1):S42-S46. 5. Rossi UG, Torcia P, Rigamonti P, et al. Tunneled central venous catheter exchange: techniques to improve prevention of air embolism. J Vasc Access. 2016;17(2):200-203.

Type of peritoneal dialysis catheter and outcomes

In peritoneal dialysis (PD), a well-functioning catheter is of great importance, because a dysfunctional catheter may be associated with incidence of peritonitis, efficiency of dialysis, and to the overall quality of treatment, representing one of the main barriers to optimal use of PD. When considering the relationship between PD catheter type and outcomes, we should keep in mind the different types of available PD catheters, those that are most commonly used in clinical practice, and the available head-to-head comparisons in the literature. The main differences in PD catheter design include the number of cuffs, the shape of subcutaneous tract (straight vs. swan neck), and the shape of intraperitoneal tract (straight vs. coiled). The availability of the best catheter design and materials, along with a skillful management of PD access, may have the greatest impact on long-term patient outcome on PD. It is now established that the use of straight catheters may improve outcomes and technique survival, but further advances in PD catheter technology can potentially improve technique survival. The self-locating PD catheter is a well established device that has not been fully studied and it may represent, based on the available observational evidence and on the clinical experience, an already existing technological advance deserving further studies.