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As the global toll on human lives and ecosystems exacted by urban pollution grows, planning tools still lack the resolution to identify priority sites where toxic pollution can be most efficiently averted at a spatial scale that matches funding and management. Here we tackle this gap by demonstrating novel scalable methods to monitor and predict urban metal pollution at high resolution (<5 m) across large areas (10,000-100,000 km 2 ) to guide pollution reduction and stormwater management. We showcase and calibrate predictive models of Zn, Cu, and a synthetic index of pollution for the Puget Sound region of Washington State, U.S., a densely urbanized yet important ecosystem of conservation interest, and exemplify their transferability across the entire United States. We leveraged widely and freely available datasets of car traffic characteristics and land use as predictor variables and trained the models with biological monitoring data of metal concentrations in epiphytic moss from >100 trees based on new rapid and low-cost protocols introduced in this study. Our model predictions, showing that 50% of the total Cu and Zn pollution across the Puget Sound watershed is deposited over only 3.3% of the land area, will allow cities to effectively and efficiently target toxic hotspots., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Objective: To assess the role of the computerized tomography (CT) scanner in cross-transmission of carbapenem-resistant Acinetobacter baumannii between hospitalized patients undergoing CT scan., Methods: A single-centre retrospective observational analysis of inpatients undergoing CT scans. Patient-unique CT scans were defined as 'index cases' (patients undergoing CT scan with carbapenem-resistant Acinetobacter baumannii (CRAB) colonization documented during the previous 60 days), 'incident cases' (patients found colonized with CRAB within 14 days following CT scan), and 'negative cases' (negative for CRAB before and after CT scan). CRAB acquisition was analysed by time interval between CT scan and CT scan of the prior index-case patient., Results: Amongst 73 047 CT scans performed over 5 years, 4834 scans were performed within 12 hours of an index case. CRAB acquisition was detected in 20 patients (incident cases), including 16/2725 (5.8/1000 scans) who underwent CT scan within 6 hours of an index-case CT scan and 4/2109 (1.9/1000 scans) who had their CT scan 7-12 hours after the CT scan of an index-case patient (p 0.033, risk ratio 3.1, 95%CI 1.03-9.25). Patient characteristics for the two time periods were similar. While not the only significant predictor of CRAB acquisition (others included age and length of hospital stay prior to the CT scan), the time elapsed from an index case remained a significant predictor for CRAB acquisition on multivariate analysis (OR 0.84, 95%CI 0.74-0.95, p 0.007)., Conclusions: Performing a CT scan within 6 hours of a CT scan performed in a CRAB-positive patient was an independent predictor of CRAB acquisition, approximately tripling the risk. This probably reflects poor infection control practice in the CT suite., (Copyright © 2021 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Background: In vitro studies suggested that circulating inflammatory cytokines cause septic myocardial dysfunction. However, no in vivo clinical study has investigated whether serum inflammatory cytokine concentrations correlate with septic myocardial dysfunction., Methods: Repeated echocardiograms and concurrent serum inflammatory cytokines (IL-1β, IL-6, IL-8, IL-10, IL-18, tumor necrosis factor-α, and monocyte chemoattractant protein-1) and cardiac biomarkers (high-sensitivity [hs] troponin-T and N-terminal pro-B-type natriuretic peptide [NT-proBNP]) were examined in 105 patients with severe sepsis and septic shock. Cytokines and biomarkers were tested for correlations with systolic and diastolic dysfunction, sepsis severity, and mortality., Results: Systolic dysfunction defined as reduced left ventricular ejection fraction (LVEF) < 50% or < 55% and diastolic dysfunction defined as e'-wave < 8 cm/s on tissue-Doppler imaging (TDI) or E/e'-ratio were found in 13 (12%), 24 (23%), 53 (50%), and 26 (25%) patients, respectively. Forty-four patients (42%) died in-hospital. All cytokines, except IL-1, correlated with Sequential Organ Failure Assessment and APACHE (Acute Physiology and Chronic Health Evaluation) II scores, and all cytokines predicted mortality. IL-10 and IL-18 independently predicted mortality among cytokines (OR = 3.1 and 28.3, P = .006 and < 0.0001). However, none of the cytokines correlated with LVEF, end-diastolic volume index (EDVI), stroke-volume index (SVI), or s'-wave and e'-wave velocities on TDI (Pearson linear and Spearman rank [ρ] nonlinear correlations). Similarly, no differences were found in cytokine concentrations between patients dichotomized to high vs low LVEF, EDVI, SVI, s'-wave, or e'-wave (Mann-Whitney U tests). In contrast, NT-proBNP strongly correlated with both reduced LVEF and reduced e'-wave velocity, and hs-troponin-T correlated mainly with reduced e'-wave., Conclusions: Unlike cardiac biomarkers, none of the measured inflammatory cytokines correlates with systolic or diastolic myocardial dysfunction in severe sepsis or septic shock.

Over 1.3 billion people live on tropical coasts, primarily in developing countries. Many depend on adjacent coastal seas for food, and livelihoods. We show how trends in demography and in several local and global anthropogenic stressors are progressively degrading capacity of coastal waters to sustain these people. Far more effective approaches to environmental management are needed if the loss in provision of ecosystem goods and services is to be stemmed. We propose expanded use of marine spatial planning as a framework for more effective, pragmatic management based on ocean zones to accommodate conflicting uses. This would force the holistic, regional-scale reconciliation of food security, livelihoods, and conservation that is needed. Transforming how countries manage coastal resources will require major change in policy and politics, implemented with sufficient flexibility to accommodate societal variations. Achieving this change is a major challenge - one that affects the lives of one fifth of humanity., (Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Study Objectives: To assess the ability of anesthesiologists to calculate weight-specific drug concentrations for continuous drug administration in children, and to evaluate the acceptance of an inhouse-developed, computer-based application for calculating drug infusions for pediatric cardiac surgery., Design: Observational study., Setting: Anesthesiology department of a tertiary-care medical center in Israel., Participants: 45 anesthesiology department staff members (attendings and residents)., Measurements: Anesthesiologists were asked to calculate the weight-based amount of drug and the corresponding amount in mL to be drawn from a standard vial and added to a 50-mL syringe in order to reach an infusion rate, where 1 mL/hr corresponds to 1 μg x kg(-1) x min(-1). The time it took to reach the result was measured. Staff members were also asked to rate the user-friendliness and usability of the program., Main Results: 41 of the original 42 participants returned the completed questionnaire. Only 6 (15%) of 41 anesthesiologists provided all the correct answers. The mean calculation time required was 205 (±53) seconds. There was no difference in success rate between attendings and residents. Incorrect calculations ranged from a drug concentration 50 times too low up to 56 times too high. Most staff members believed that the computer-based application to perform these calculations reduced errors (65%) and workload (81%), and improved patient treatment (71%). This application was rated as very user-friendly., Conclusions: Anesthesiologists have difficulty calculating pediatric drug concentrations for continuous drug infusions. The correct calculations are time-consuming. Incorrect calculations may lead to dangerously high or low doses. A computer-based application to calculate drug concentrations was rated as very useful and user-friendly., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: The sterile conditions used when inserting a central venous catheter (CVC) might be thought to decrease the contamination rate of blood cultures taken at CVC insertion; however, a previous retrospective study showed the opposite, that such blood cultures are contaminated more frequently than peripheral venipuncture blood cultures. The current study explored whether use of the CVC nonwire hub as a source of blood cultures decreased contamination while maintaining detection of true pathogens., Methods: A prospective, observational study was performed from June 2010 to May 2011 in the general ICU of an academic, tertiary referral center. The proportions of blood cultures taken from wire and nonwire CVC hubs growing contaminants and true pathogens were compared. Risk factors for blood culture contamination were identified, and multivariate analysis was used to identify independent predictors of blood culture contamination., Results: Among 313 blood cultures taken from 227 CVCs in 139 patients, 27 of 141 wire hub (19%) vs nine of 172 nonwire hub (5%) cultures were contaminated (P &lt; .001). Only hub of blood culture origin was associated with contamination on multivariate analysis (OR, 4.3; 95% CI, 1.9-9.5; P &lt; .001). True pathogens grew in 19 of 141 wire hub (13%) vs 27 of 172 nonwire hub (16%) cultures (P = .581)., Conclusions: A higher proportion of blood cultures taken from the CVC lumen exposed to the guidewire were contaminated when compared with nonwire hub cultures; detection of true pathogens was equivalent. To limit detrimental sequelae of blood culture contamination, blood cultures obtained at CVC insertion should be taken from the nonwire hub.

Background: Great variability exists in the occurrence of antibiotic-resistant bacteria in ICUs around the world. The contribution of specific ICU care variables to these geographic variations is unknown., Methods: ICU patients from two ICUs (in Jerusalem and Toronto) who were admitted for > 48 h and who grew a resistant bacteria in any culture during ICU admission were compared with those without resistant organisms across a range of demographic and ICU care interventions. Significant variables were investigated with logistic regression to identify factors predictive of infection/colonization with a resistant organism., Results: Resistant organisms were acquired by 82/423 (19%) patients. Patients acquiring a resistant organism had a higher incidence of diabetes mellitus (21/82, 26% vs 52/341, 15%; P = .026), were more frequently admitted from another ICU (17/82, 21% vs 33/341, 10%; P = .005), received more antibiotics in the ICU (19 +/- 17 vs 14 +/- 14 days; P = .005), and had more ventilator (10 +/- 10 vs 7 +/- 8; P = .031) and central line days (10 +/- 8 vs 7 +/- 8; P < .001). These patients had a lower incidence of limitation-of-therapy orders (9/82, 11% vs 78/341, 23%; P = .015). Only the absence of a limitation-of-therapy order (odds ratio, 2.62; 95% CI, 1.21-5.68; P = .014) was independently associated with the acquisition of resistant organisms. Further, among ICU fatalities, 5/45 (11%) patients acquired a resistant organism prior to withdrawal vs 17/44 (39%) nonwithdrawal fatalities (P = .003). Nonwithdrawal fatalities received significantly more third-line antibiotics (7 +/- 14 vs 2 +/- 4; P = .031) despite similar ICU lengths of stay (15 +/- 21 days for nonwithdrawal fatalities vs 10 +/- 11 for withdraw fatalities; P = .210), Conclusions: End-of-life treatment is independently associated with acquisition of resistant bacteria. Patients dying without withdraw orders receive more antibiotics and develop more resistant organisms. These patients may represent a reservoir of resistant bacteria in the ICU.

Background: Approximately 15% of nosocomial infections in the ICU result from spread of bacteria on caregivers' hands. The routine chest radiograph provides an unexamined opportunity for bacterial spread: close contact with each patient and sequential examination of ICU patients. This study examined infection control procedures performed during routine chest radiographs, assessed whether resistant bacteria were transferred to the radiograph machine, and determined whether improved infection control practices by radiograph technicians could reduce bacterial transfer., Methods: Radiograph technicians were observed performing chest radiographs on all ICU patients. Culture specimens were taken from the radiograph machine. An educational intervention directed at technicians was instituted, and its effect on infection control and machine contamination was measured., Results: Surveillance of 173, 113, and 120 chest radiographs during observation, intervention, and follow-up periods was performed. Adequate infection control was practiced during the performance of 2 of 173 observation period radiographs (1%), 48 of 113 intervention period radiographs (42%; p < 0.001), and 12 of 120 follow-up period radiographs (10%; (p < 0.001) [follow-up vs intervention and observation periods]. Radiograph machine surface culture samples yielded resistant Gram-negative bacteria on 12 of 30 occasions (39%), 0 of 29 occasions, and 7 of 14 occasions (50%), respectively, for the observation, intervention, and follow-up periods (p < 0.001)., Conclusion: Multiresistant bacteria are frequently transferred from patients to the radiograph machine in the presence of poor infection control practices, and may be a source of cross-infection/colonization. Improved infection control practices decrease the occurrence of resistant organisms on the radiograph equipment. Radiograph technicians should be included in efforts to improve infection control measures.

The hyperperfusion syndrome is a rare delayed postoperative complication of carotid endarterectomy (CEA) characterized by headache and seizure, with or without intracranial edema or hemorrhage. Between January 1996 and December 2003, 1,602 CEAs were performed. Six patients (0.4%) developed symptoms of hyperperfusion within 2 weeks of surgery. All patients had critical stenoses, five > or =90% and one 80-90%, with poor backbleeding from the distal internal carotid artery noted at operation in all cases. Five patients were asymptomatic prior to operation; one had a hemispheric transient ischemic attack. Three patients had severe contralateral internal carotid disease (two occlusions and one severe stenosis). Two patients developed severe, self-limiting headache that prolonged hospitalization. Three patients had ipsilateral intracranial bleeding, two occurring after an uneventful postoperative course. After initial discharge from the hospital, severe intracranial hemorrhage caused death in two patients. One patient experienced focal seizures 1 week after discharge. Hypertension did not appear to be related to the symptoms in any case. During the study period, the hyperperfusion syndrome caused three of five perioperative strokes (60%) and two of seven deaths (29%) in the entire endarterectomy population. Although rare, the hyperperfusion syndrome accounts for a significant percentage of the neurological morbidity and mortality following CEA.

Radiofrequency ablation of the greater saphenous vein (GSV) has been proposed as an alternative to conventional ligation and stripping in the treatment of varicose veins. We have reviewed our initial experience with this new technology in 28 procedures on 24 patients. Preoperative duplex scans confirmed venous valvular incompetence of the GSV in all patients. Intraoperative ultrasound was used to measure the depth of the GSV, to precisely place the radiofrequency catheter adjacent to the saphenofemoral junction, and to confirm the results of the ablative procedure. Occlusion of the GSV was seen on 96% of completion scans and in all patients within 1 week of the procedure. Duplex scans were available for 21 limbs at 3 months and for 3 at 1 year. Persistent occlusion was documented in all cases. No patient had paresthesias or thermal skin injury. Two patients had transient superficial thrombophlebitis around the knee in a treated segment of the GSV. One patient was found to have extension of an asymptomatic, nonocclusive thrombus into the common femoral vein on a routine scan 3 days after surgery. Postoperative patient questionnaires showed that 96% of respondents were very satisfied with the procedure. Radiofrequency ablation of the GSV appears to be a safe alternative to conventional stripping and ligation. Subjective assessment by the surgeons suggests an earlier return to work and active lifestyle compared to traditional extirpative techniques. Longer follow-up is required to establish the durability of the procedure.

Spontaneous infrarenal abdominal aortic dissection (SIAAD) is rare. Patients with SIAAD may be asymptomatic or may present with abdominal pain or lower extremity ischemia. We describe a case report of a patient with SIAAD who presented with claudication. We reviewed the English literature on this disorder and specifically evaluated the differences between patients on the basis of their presenting symptoms. Patients who had SIAAD and lower extremity ischemia were more likely to have the dissection process extend into the iliac or femoral artery and were less likely to have an associated abdominal aortic aneurysm. Aortic rupture in the presence of SIAAD was associated with increased risk of death.

Carotidynia is a term that is best defined by neck pain associated with tenderness over the carotid artery. The differential diagnosis of this entity is broad and includes vascular disorders such as carotid dissection, aneurysm, occlusion, and arteritis. We describe the first reported case of carotidynia caused by septic embolization to the carotid bulb and offer a logical plan for its management.

Introduction: Arterial dissection commonly affects the thoracic aorta and is associated with high morbidity and mortality rates. Although dissection of the abdominal aorta is considered rare, liberal use of diagnostic computed tomographic scan imaging for evaluation of abdominal pain has identified this process with increasing frequency. Because the clinical features and therapeutic options of isolated abdominal aortic dissection are not well characterized, we reviewed our recent experience and provide an algorithm for treatment., Patients and Results: Since 1996, we have treated 10 patients with abdominal aortic dissection. The mean age was 62 +/- 17 years, and 40% were female. Presentation included abdominal pain in seven patients and lower extremity ischemia in one patient. Dissection was asymptomatic in two of the patients. Hypertension, smoking history, remote trauma, and claudication were noted in four, three, two, and two of the patients, respectively. Three patients had abdominal tenderness, three had a pulsatile mass, and five had a benign abdominal examination. The diagnosis of dissection was made on abdominal computed tomographic scan in eight cases, on arteriogram in one case, and at operation in one case. No patient had an associated thoracic aortic dissection. The dissection flap originated below or at the renal arteries in nine of the cases and at the superior mesenteric artery in one case. Length of the dissection ranged between 21 and 110 mm, and in three patients, the dissection flap extended beyond the aortic bifurcation into the common iliac arteries. In three patients who had an aortogram, evidence of flow limitation was found on the basis of the presence of aortic stenosis or occlusion. Treatment consisted of aortic stent graft deployment in one patient, direct aortic reconstruction in three patients, and observation in the remaining six patients., Conclusion: Although the natural history of isolated abdominal aortic dissection has not been well defined, our experience adds to the understanding of this rare process. Because aneurysmal degeneration can occur, close surveillance is indicated if definitive treatment is not used initially. Patients with ischemic symptoms and those with intractable pain need intervention, the nature of which should be based on risk profile and aortoiliac anatomy.

Transvenous placement of inferior vena cava (IVC) filters has become commonplace in selected patients with deep venous thrombosis (DVT) and pulmonary embolism (PE). IVC filters have been shown to have excellent therapeutic efficacy and low complication rates. Penetration of the IVC by filter hooks or struts has been reported and commonly noted to be inconsequential. We report a laceration of a lumbar artery by a stainless steel Greenfield (SSG) filter strut that resulted in a near fatal hemorrhage, and review the world literature on caval perforation by IVC filters.