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Previous research suggested that supervised machine learning can be utilized to detect information operations (IO) on social media. Most of the related research assumes that the new data will always be available in the exact timing that models set to be updated. In practice, however, the detection and attribution of IO accounts is time-consuming. There is thus a mismatch between the performance assessment procedures in existing work and the real-world problem they seek to solve. We bridge this gap by demonstrating how active learning approaches can extend the application of classifiers by reducing their dependence on new data. We evaluate the performance of an existing classifier when it gets updated according to five active learning strategies. Using state-sponsored information operation Twitter data, the results show that if querying from Twitter is possible, the best active learning strategy requires 5–10 times less tweets than the original model while only showing 1–3% reduction in the average monthly F1 scores across countries and prediction tasks. If querying from Twitter is not possible, the corresponding active learning strategy requires 5–10 times less tweets while showing 1–9% reduction in the average monthly F1 scores. Depending on the country, a hand-full to few hundred new ground-truth examples would suffice to achieve a reasonable performance.

Background: PICC-ports may be defined as totally implantable central venous devices inserted in the upper limb using the current state-of-the-art techniques of PICC insertion (ultrasound-guided venipuncture of deep veins of the arm, micro-puncture kits, proper location of the tip preferably by intracavitary ECG), with placement of the reservoir at the middle third of the arm. A previous report on breast cancer patients demonstrated the safety and efficacy of these devices, with a very low failure rate. Methods: This retrospective multicenter cohort study—developed by GAVeCeLT (the Italian Group of Long-Term Venous Access Devices)—investigated the outcomes of PICC-ports in a large cohort of unselected patients. The study included 4480 adult patients who underwent PICC-port insertion in five Italian centers, during a period of 60 months. The primary outcome was device failure, defined as any serious adverse event (SAE) requiring removal. The secondary outcome was the incidence of temporary adverse events (TAE) not requiring removal. Results: The median follow-up was 15.5 months. Device failure occurred in 52 cases (1.2%), the main causes being local infection (n = 7; 0.16%) and CRBSI (n = 19; 0.42%). Symptomatic catheter-related thrombosis occurred in 93 cases (2.1%), but removal was required only in one case (0.02%). Early/immediate and late TAE occurred in 904 cases (20.2%) and in 176 cases (3.9%), respectively. Conclusions: PICC-ports are safe venous access devices that should be considered as an alternative option to traditional arm-ports and chest-ports when planning chemotherapy or other long-term intermittent intravenous treatments.

In the last decade, a new type of brachial port has been introduced in clinical practice, the so-called “PICC-port.” This is a brachial port, but inserted according to the methodologies and technologies currently adopted for the insertion of peripherally inserted central catheters (PICCs). Several studies have shown that PICC-port insertion is safe, not associated with any relevant immediate or early complication, and that the expected incidence of late complications is significantly lower if compared to “traditional” brachial ports (i.e. inserted without ultrasound guidance). Furthermore, PICC-ports yield excellent esthetic results and are associated with optimal patient compliance. This paper describes an insertion bundle—developed by GAVeCeLT, the Italian Group of Long Term Venous Access Devices, and nicknamed “SIP-Port” (Safe Insertion of PICC-Ports)—which consists of few evidence-based strategies aiming to further minimize all immediate, early, or late complications potentially associated with PICC-port insertion. Also, this insertion bundle has been developed for the purpose of defining more closely the differences between a traditional brachial port and a PICC-port. The SIP-Port bundle is currently adopted by all training courses on PICC-port insertion held by GAVeCeLT. It includes eight steps: (1) preprocedural ultrasound assessment utilizing the RaPeVA (Rapid Peripheral Venous Assessment) protocol; (2) appropriate skin antiseptic technique and maximal barrier precautions; (3) choice of appropriate vein, in terms of caliber and site; (4) clear identification of the median nerve and of the brachial artery during the venipuncture; (5) ultrasound-guided puncture and cannulation of the vein; (6) ultrasound-guided tip navigation; (7) intra-procedural assessment of tip location by intracavitary ECG or by trans-thoracic echocardiography; (8) appropriate creation and closure of the subcutaneous pocket.

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.

We read with great interest the study recently published by Wu et al., investigating the incidence of catheter- related thrombosis (CRT) in the largest cohort of criti- cally ill patients thus far [1]. The authors screened by ultrasound (US) the venous district immediately before and daily after the placement of a central venous cath- eter (CVC), and reported a CRT incidence of 16.9% (213/1262), mostly affecting the left side and the internal jugular vein, which accounted for the 54% of CVCs.

In the past 5 years, non-dialysis femoral venous access has changed in terms of indications, techniques of insertion, and expected incidence of complications. To the traditional non-emergency indication for femoral catheters—obstruction of the superior vena cava—many other indications have been added, both in intensive and non-intensive care. The insertion technique has evolved, thanks to ultrasound guided venipuncture, tunneling, and ultrasound based intraprocedural tip location. Insertion of femorally inserted central catheters may be today regarded as a procedure with an extremely low intraprocedural and post-procedural risk. The risk of infection is reduced by the possibility of the exit site at mid-thigh, by the use of cyanoacrylate glue for sealing the exit site, and by appropriate intraprocedural strategies of infection prevention. The risk of catheter-related thrombosis is low, due to several concomitant strategies: a proper match between vein diameter and catheter caliber; an accurate intraprocedural assessment of tip location by ultrasound and/or intracavitary ECG; the consistent use of ultrasound guided venipuncture and micro-introducer kits; an adequate stabilization of the catheter at the exit site. The risk of mechanical complications and the risk of lumen occlusion are minimized when using polyurethane, power injectable catheters. All these novelties have brought a revolution in the field of femoral venous access, so that this route may be considered as safe and effective as other approaches to central venous catheterization.

Purpose: Ultrasound-guided peripherally inserted central catheters (PICCs) are increasingly used in children, though their insertion may be limited by the small caliber of the deep veins of the arm. Previous studies have suggested to use age or weight as a guide to the feasibility of PICC insertion. We have planned an observational study with the purpose of identifying the actual feasibility of PICC insertion based on the ultrasound evaluation of the deep veins of the arm in groups of children of different weight range. Methods: We have studied 252 children weighing between 2.5 and 20 kg, divided in five different groups (group 1: 2.5-4 kg; group 2: 4.1-7 kg; group 3: 7.1-10 kg; group 4: 10.1-15 kg; group 5: 15.1-20 kg): the caliber of brachial vein, basilic vein, and cephalic vein at mid-upper arm + the caliber of the axillary vein at the axilla were measured by ultrasound scan. Results: Veins of caliber >3 mm (appropriate for insertion of a 3 Fr non-tunneled PICC) were found at mid-upper arm in no child of group 1 or 2, in 13% of group 3, in 28% of group 4, and in 54% of group 5. An axillary vein >3 mm (appropriate for insertion of a 3 Fr tunneled PICC) were found in 5.8% of group 1, 30.6% of group 2, 67% of group 3, 82% of group 4, and 94% of group 5. Conclusions: The age and the weight of the child have a small role in predicting the caliber of the veins of the arm. Veins should be measured case by case through a proper and systematic ultrasound evaluation; however, the clinician can expect that insertion of a 3 Fr PICC may be feasible in one third of children weighing between 4 and 7 kg, and in most children weighing more than 7 kg, especially if adopting the tunneling technique.

Physical exercise is often encouraged in cancer patients, mainly for the purpose of rehabilitation and for its psychological benefit. Some authors also suggest that exercise—specially in patient with peripherally inserted central venous access devices—may contribute to reduce the risk of catheter-related thrombosis. Still, the impact of physical exercise on the risk of device-related complications is not yet defined. We report a case of secondary migration of the tip of an arm port, caused by high-intensity exercise in a woman undergoing chemotherapy because of ovarian cancer. Tip migration was suspected because of malfunction (persistent withdrawal occlusion) and diagnosis established after ultrasound examination and chest x-ray. Even if exercise may yield benefit in the cancer patient on chemotherapy, the risk of mechanical complication of the venous access device—such as tip migration—should be considered in the case of high-intensity exercise.

Muscle wasting (sarcopenia) is one of the hallmarks of critical illness. Patients admitted to intensive care unit develop sarcopenia through increased protein catabolism, a decrease in protein syntheses, or both. Among the factors known to promote wasting are chronic inflammation and cytokine imbalance, insulin resistance, hypermetabolism, and malnutrition. Moreover, muscle wasting, known to develop in chronic kidney disease patients, is a harmful consequence of numerous complications associated with deteriorated renal function. Plenty of published data suggest that serum creatinine (SCr) reflects increased kidney damage and is also related to body weight. Based on the concept that urea and creatinine are nitrogenous end products of metabolism, the urea:creatinine ratio (UCR) could be applied but with limited clinical usability in case of kidney damage, hypovolemia, excessive, or protein intake, where UCR can be high and independent of catabolism. Recent data suggest that the sarcopenia index should be considered an alternative to serum creatinine. It is more reliable in estimating muscle mass than SCr. However, the optimal biomarker of catabolism is still an unresolved issue. The SCr is not a promising biomarker for renal function and muscle mass based on the influence of several factors. The present review highlights recent findings on the limits of SCr as a surrogate marker of renal function and the assessment modalities of nutritional status and muscle mass measurements.

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Background: Chest-to-arm (CTA) tunneling has been described recently as a technique that allows an optimal exit site at mid-arm even in chronically ill patients with complex clinical issues and challenging problems of vascular access. Method: We adopted CTA tunneling in oncologic and in non-oncologic patients, in totally implanted and in external devices, for both medium and long-term intravenous treatments. We report our experience with 60 cases of CTA tunneling: 19 patients requiring a totally implantable device, who had bilateral contraindication to venous access at the arm and bilateral contraindication to placement of the pocket in the infra-clavicular area; 41 patients requiring an external central venous catheter, who had bilateral contraindication to insertion of peripherally inserted central catheters or femoral catheters, as well as contraindication to an exit site in the infraclavicular area. All venous access devices were inserted with ultrasound guidance and tip location by intracavitary electrocardiography, under local anesthesia. Results: There were no immediate or early complications. Patients with CTA-ports had no late complications. In patients with CTA-tunneled external catheters, there were two dislodgments, four episodes of central line associated blood stream infections, and one local infection. There were no episodes of venous thrombosis or catheter malfunction. Conclusion: Our experience suggests that CTA tunneling is a safe maneuver, with very low risk of complications, and should be considered as an option in patients with complex venous access.

The aims of our systematic review were to quantify the expected rate of procedural success, early and late complications during CIED implantation using US-guided puncture of the axillary vein and to perform a meta-analysis of those studies that compared the US technique (intervention) versus conventional techniques (control) in terms of complication rates. MEDLINE, ISI Web of Science, and EMBASE were searched for eligible studies. Pooled Odds Ratio (OR) and Pooled Mean Difference (PMD) for each predictor were calculated. The quality of evidence (QOE) was evaluated according to the GRADE guidelines. Thirteen studies were included a total of 2073 patients. The overall success of US-guided venipuncture for CIED implantation was 96.8%. As regards early complications, pneumothorax occurred in 0.19%, arterial puncture in 0.63%, and severe hematoma/bleeding requiring intervention in 1.1%. No cases of hemothorax, brachial plexus, or phrenic nerve injury were reported. As regards late complications, the incidence of pocket infection, venous thromboembolism, and leads dislodgement was respectively 0.4%, 0.8%, and 1.2%. In the meta-analysis (five studies), the intervention group (US-guided venipuncture) had a trend versus a lower likelihood of having a pneumothorax (0.19% vs 0.75%, p = 0.21), pocket hematoma (0.8% vs 1.7%, p = 0.32), infection (0.28% vs 1.05%, p = 0.29) than the control group, but this did not reach statistical significance. The overall QOE was low or very low. In conclusions we found that the US-guided axillary venipuncture for CIEDs implantation was associated with a low incidence of early and late complications and a steep learning curve.

Persistent withdrawal occlusion is a specific catheter malfunction characterized by inability to withdraw blood through the device while infusion is maintained. The main causes are fibroblastic sleeve and tip malposition (associated or not to venous thrombosis around the tip). All current guidelines recommend infusing vesicant/antiblastic drugs through a central venous port only after assessment of blood return. In PWO, blood return is impossible. We have recently started to assess the intravascular position of the tip and the delivery of the infusion in the proximity of the cavo-atrial junction utilizing transthoracic/subxiphoid ultrasound with the ‘bubble test’. We found that this is an easy, real-time, accurate and safe method for verifying the possibility of using a port for chemotherapy even in the absence of blood return, as it occurs with persistent withdrawal occlusion.

Background: Intraprocedural catheter tip location is currently recommended. Intracavitary EGC and ultrasound are the preferred methods of tip location for catheters with their tip in the superior vena cava or in the right atrium. Though, the best method of intraprocedural tip location for catheters with their tip in the inferior vena cava is still uncertain. One possibility is to visualize the subdiaphragmatic inferior vena cava by ultrasound, using either the transhepatic or the subxiphoid view. Methods: In this prospective study, we compared two different ultrasound windows for the visualization of the inferior vena cava (transhepatic vs subxiphoid) for the purpose of localizing the catheter tip during the insertion of femorally inserted central catheters. Results: We studied 249 consecutive insertions of central catheters via the superficial femoral vein. Intraprocedural location of the catheter tip was performed by ultrasound, using both transhepatic and subxiphoid view. Visualization of the inferior vena cava was possible only in 81 cases (32.5%) with the subxiphoid view, but it was always possible in all 249 cases with the transhepatic view. The catheter tip was localized in 15 patients out of 81 with the subxiphoid view (18.5%); the transhepatic view allowed the visualization of the tip in all 249 patients. Conclusions: The applicability of the subxiphoid window has several limitations, both in terms of visualization of the inferior vena cava and localization of the catheter tip. The transhepatic view should be the preferred method for intraprocedural ultrasound localization of the catheter tip in the inferior vena cava.

Background: The ideal intraprocedural method for tip location during insertion of femorally inserted central catheters (FICCs) is still a matter of debate. When the catheter tip is meant to be in the right atrium or in the supradiaphragmatic inferior vena cava (IVC), tip location by either intracavitary electrocardiography or transthoracic echocardiography may be accurate and easy to perform. When the catheter tip is planned to be placed in the subdiaphragmatic IVC, fluoroscopy—though inaccurate and unsafe—has been regarded as the only option for intraprocedural tip location. Methods: We have investigated prospectively the applicability and feasibility of transhepatic ultrasound as intraprocedural method for assessing the location of the catheter tip in the subdiaphragmatic tract of IVC, during FICC insertion. Results: We enrolled 169 consecutive patients undergoing FICC insertion by ultrasound guided puncture of the superficial femoral vein. In 165 out of 169 patients, the subdiaphragmatic IVC was visualized by the transhepatic ultrasound view. In all cases of IVC visualization, the catheter tip could be identified by ultrasound, either directly (direct evidence of the tip inside the vein) or indirectly (enhanced visualization of the tip after “bubble test”). There was no immediate or early complication, and very few late complications. Conclusion: The intraprocedural method of tip location of FICCs by transhepatic ultrasound was applicable in 97.6% of cases and feasible in 100%. When the position of the catheter tip is planned to be in the subdiaphragmatic IVC, this method of tip location is accurate, safe, and inexpensive, and should be considered as an alternative to fluoroscopy.

This report presents tabulations from Census 2000 data on people enumerated at emergency and transitional shelters. This includes shelters for people experiencing homelessness; shelters for children who are runaways, neglected, or without conventional housing; transitional shelters for people without conventional housing; and hotels and motels used to provide shelter for people without conventional housing. The report provides data on the following issues: who the people are without conventional housing in Census 2000; how people experiencing homelessness are included in Census 2000; to what extent the service-based enumeration operation provides a count of the population experiencing homelessness or of the population using services; important issues to consider when reviewing the population data for emergency and transitional shelters; Census 2000 data on the emergency and transitional shelter population; characteristics of the population in emergency and transitional shelters in Census 2000; and information for counties and census tracts on the population in emergency and transitional shelters that is available on the Internet. (SM)