Prevention of catheter related blood stream infections (CRBSI) and salvage of infected central venous catheters (CVC) are vital to maintaining long term venous access in patients needing home ...parenteral nutrition (HPN). It remains unclear as to whether patients are best trained for catheter care at home or in hospital or whether CRBSIs are lower if the patient self-cares for the CVC. Furthermore, there is minimal data on the longer term outcome following salvage of infected catheter and limited consensus on agreed protocols for catheter salvage.
We conducted a retrospective 5-year evaluation of CRBSI occurrence and CVC salvage outcomes in adult patients requiring HPN managed at a national UK Intestinal Failure Unit from 2012 to 2016. Prior to 2012, patients were primarily trained to administer PN in hospital; thereafter, patients underwent training at home.
A total of 134 CRBSI were recorded in 92 patients (62 patients with a single CRBSI and 30 patients with more than 1 CRBSI) in a cohort of 559 HPN patients, with a total of 1163 HPN years. The overall CRBSI rate was 0.31 per 1000 catheter days. CNS were the most common isolates (41/134 (30.5%)), followed by polymicrobial infections (14/134 (10.4%)), Klebsiella spp. (16/134 (11.9%)) and methicillin – sensitive Staphylococcus aureus (MSSA) 5/134 ((3.7%)). Salvage was not attempted in 34 cases due to methicillin – resistant (MRSA) infection (1/34), fungal infection (13/34) or clinical instability due to sepsis (20/34). Of the 100 cases where salvage was attempted, 67% were successful. 82.8% of CNS salvage attempts were successful; there was no difference in salvage rates between CNS CRBSIs salvaged with a 10-day (22/26) or 14-day protocol (7/9) (p = 0.4). CRBSI rate, in those cared for by trained home care nurses was the lowest at 0.270 (self care: 0.342 and non-medical carer (e.g. family member): 0.320) (p = 0.03).
We previously reported a sustained very low CRBSI rate in a large cohort of HPN patients in a national unit; we now further report that this is not influenced by training patients at home rather than in hospital but is influenced by the individual managing the catheter at home. CNS remains the primary cause of CRBSIs and can be successfully salvaged with a reduced duration of antibiotic therapy compared to our previous experience.
These evidence-based guidelines are an updated version of those published in 2006. They have been produced after a literature review of the treatment and prophylaxis of methicillin-resistant ...Staphylococcus aureus (MRSA). The guidelines aim to complement those recently published for the antibiotic treatment of common and emerging community-onset MRSA infections in the UK. The guidelines have reviewed and updated, where appropriate, previous recommendations, taking into account any changes in the UK epidemiology of MRSA, ongoing national surveillance data and the value of new antistaphylococcal agents licensed for use in UK practice. Emerging therapies that have not been licensed for UK use are not reviewed, but their future potential role has been mentioned where deemed appropriate. Recommendations are given for the treatment of common infections caused by MRSA, elimination of MRSA from carriage sites and prophylaxis of surgical site infection.
Extraordinary video and hydrophone observations of a submarine explosive eruption were made with a remotely operated vehicle in April 2006 at a depth of 550–560 m on NW Rota‐1 volcano in the Mariana ...arc. The observed eruption evolved from effusive to explosive, while the eruption rate increased from near zero to 10–100 m3/h. During the peak in activity, cyclic explosive bursts 2–6 min long were separated by shorter non‐eruptive pauses lasting 10–100 s. The size of the ejecta increased with the vigor of the explosions. A portable hydrophone deployed near the vent recorded sounds correlated with the explosive bursts; the highest amplitudes were ∼50 dB higher than ambient noise at frequencies between 10 and 50 Hz. The acoustic data allow us to quantify the durations, amplitudes, and evolution of the eruptive events over time. The low eruption rate, high gas/lava ratio, and rhythmic eruptive behavior at NW Rota‐1 are most consistent with a Strombolian eruptive style. We interpret that the eruption was primarily driven by the venting of magmatic gases, which was also the primary source of the sound recorded during the explosive bursts. The rhythmic nature of the bursts can be explained by partial gas segregation in the conduit and upward migration in a transitional regime between bubbly flow and fully developed slug flow. The strongest explosive bursts were accompanied by flashes of red glow and oscillating eruption plumes in the vent, apparently caused by magma‐seawater interaction and rapid steam formation and condensation. This is the first time submarine explosive eruptions have been witnessed with simultaneous near‐field acoustic recordings.
Submarine landslides are an important process in volcano growth yet are rarely observed and poorly understood. We show that landslides occur frequently in association with the eruption of West Mata ...volcano in the NE Lau Basin. These events are identifiable in hydroacoustic data recorded between ~5 and 20 km from the volcano and may be recognized in spectrograms by the weak and strong powers at specific frequencies generated by multipathing of sound waves. The summation of direct and surface‐reflected arrivals causes interference patterns in the spectrum that change with time as the landslide propagates. Observed frequencies are consistent with propagation down the volcano's north flank in an area known to have experienced mass wasting in the past. These data allow us to estimate the distance traveled by West Mata landslides and show that they travel at average speeds of ~10–25 m/s.
Key Points
Submarine landslides occurred frequently during the West Mata eruptionSubmarine landslide speed can be estimated from hydroacoustic data
Summary Between December 2007 and July 2008, three neonates in a neonatal intensive care unit (NICU) in Salford, UK, were diagnosed with primary cutaneous aspergillosis (PCA) due to Aspergillus ...fumigatus . The first PCA case, in December 2007, developed multi-organ failure leading to death within a short time frame: the other two cases survived after treatment with intravenous antifungal therapy followed by oral posaconazole. Air, surface, and water samples were collected within the NICU and from the incubators that were occupied by the neonates. All recovered fungal isolates were confirmed as A. fumigatus by sequencing the beta-tubulin region. Microsatellite strain typing demonstrated genotypically related A. fumigatus isolates from the neonates and the humidity chambers (HCs) of the neonates’ incubators, suggesting that the source of the infection may have been the HCs/incubators used in the NICU. Aspergillus strain typing may be a useful tool in clinical outbreak settings to help understand the source of exposure and to design targeted environmental interventions to prevent future infections.
The management of intestinal failure (IF) requires safe and sustained delivery of parenteral nutrition (PN). The long-term maintenance of central venous catheter (CVC) access is therefore vital, with ...meticulous catheter care and salvage of infected CVCs being of prime importance. CVC-related infection and loss of intravenous access are important causes of morbidity and mortality in IF. Avoidance, prompt recognition and appropriate management of CVC-related infections are crucial components of IF care. However, there are few, if any, data on the occurrence of CVC-related infections in patients with acute, type 2, IF managed on a dedicated IF unit and no data on the salvage outcomes of infected CVCs in this group of patients.
This is a retrospective observational study conducted between January 2011 and July 2017. All patients with acute, type 2 IF newly admitted to a national U.K. IF unit (IFU) during these dates were included. All patients admitted to the unit with a CVC in place underwent immediate ‘screening’ paired central and peripheral blood cultures on arrival before the CVC was used for any infusate. A prospectively maintained database was used to record all confirmed catheter-related blood stream infections (BSI)/colonisations, demographic and clinical data. Diagnosis of catheter-related BSI/colonisation was based on quantitative and qualitative analysis of paired central and peripheral blood cultures. A standardized 10–14-day catheter salvage treatment protocol involving antibiotic and urokinase CVC locks and systemic antibiotic administration was used to salvage any infected or colonised CVCs, as appropriate. The CVC was not used for PN until successful salvage had been confirmed by negative blood cultures drawn 48 h after antibiotic completion. The development of a subsequent catheter-related BSI was recorded for all patients, both during the remaining in-patient stay on the IFU and after discharge home on PN.
Of the 509 patients with type 2 IF admitted to the IFU during the study period, 341 (54% female; mean age 54.6 (range 16–86 years)) had an indwelling CVC that had been placed in the referring hospital. Surgical complications and mesenteric ischaemia were the most common underlying disease aetiologies. Sixty-five of 341 (19.1%) patients had an infected/colonised CVC on the initial screening set of blood cultures. A successful CVC salvage rate of 91% was achieved in this cohort after antibiotic therapy. The subsequent in-patient catheter-related BSI rate for those admitted with a CVC (n = 341) on the IFU was 0.042 per 1000 catheter days, over a total of 23,548 in-patient catheter days. Two hundred and seventy nine of 341 patients were discharged on home PN (HPN); with a subsequent catheter-related BSI rate on HPN of 0.22 per 1000 catheter days (mean duration of HPN = 778 catheter days (range:)) over a follow-up period of 216,944 out-patient catheter days. There was no increased risk of HPN-related catheter-related BSI (p = 0.09) or mortality (p = 0.4) in those admitted with an infected CVC.
This is the first study to report catheter-related BSI/colonisation rates and salvage outcomes in patients with type 2 IF newly admitted to a dedicated IF Unit. We report that nearly one-fifth of all patients were referred with evidence of a catheter related BSI/colonisation; despite this, successful catheter salvage is possible and, with stringent CVC care, an extremely low subsequent catheter related BSI rates can be achieved and maintained during in-patient stay on a dedicated IF Unit and after discharge on HPN. These data provide novel evidence to support ESPEN recommendations that patients with type 2 IF are managed on a dedicated IF Unit.
Urine patches deposited in pasture by grazing animals are sites of reactive nitrogen (N) loss to the environment due to high concentrations of N exceeding pasture uptake requirements. In order to ...upscale N losses from the urine patch, several urination parameters are required, including where, when and how often urination events occur as well as the volume and chemical composition. There are limited data available in this respect, especially for sheep. Here, we seek to address this knowledge gap by using non-invasive sensor-based technology (accelerometers) on ewes grazing in situ, using a Boolean algorithm to detect urination events in the accelerometer signal. We conducted an initial study with penned Welsh Mountain ewes (n = 5), with accelerometers attached to the hind, to derive urine flow rate and to determine whether urine volume could be estimated from ewe squat time. Then accelerometers attached to the hind of Welsh Mountain ewes (n = 30 at each site) were used to investigate the frequency of sheep urination events (n = 35 946) whilst grazing two extensively managed upland pastures (semi-improved and unimproved) across two seasons (spring and autumn) at each site (35–40 days each). Sheep urinated at a frequency of 10.2 ± 0.2 and 8.1 ± 0.3 times per day in the spring and autumn, respectively, while grazing the semi-improved pasture. Urination frequency was greater (19.0 ± 0.4 and 15.3 ± 0.3 times per day in the spring and autumn, respectively) in the unimproved pasture. Ewe squat duration could be reliably used to predict the volume of urine deposited per event and was thus used to estimate mean daily urine production volumes. Sheep urinated at a rate of 16.6 mL/s and, across the entire dataset, sheep squatted for an average of 9.62 ± 0.03 s per squatting event, producing an estimated average individual urine event volume of 159 ± 1 mL (n = 35 946 events), ranging between 17 and 745 mL (for squat durations of 1 to 45 s). The estimated mean daily urine volume was 2.15 ± 0.04 L (n = 2 669 days) across the entire dataset. The data will be useful for modelling studies estimating N losses (e.g. ammonia (NH3) volatilisation, nitrous oxide (N2O) emission via nitrification and denitrification and nitrate (NO3−) leaching) from urine patches.
Coral reef symbioses are well-established models for studying multi-level networks of species interactions that provide nutritional benefits to partners. While the contributions of endosymbionts to ...cnidarian hosts have been extensively documented, relatively little is known about how exosymbionts contribute to nutrient cycling in coral reef cnidarians. We investigated exosymbiotic sources of ammonia and their contributions to physiological processes in Caribbean corkscrew sea anemones Bartholomea annulata. In laboratory experiments, anemones absorbed ammonia from seawater, which significantly enhanced the mitotic index of their endosymbiotic microalgae Symbiodinium, while anemone shrimp presence alone had no effect. Anemone shrimps excreted ammonia at much slower rates than anemones were able to absorb it, indicating that shrimp alone were not able to meet host nitrogen demand. Client fishes excreted ammonia ~10× more rapidly than did associated shrimps. On Caribbean coral reefs, anemone shrimps attract diverse client fishes through their parasite-cleaning behavior; these fishes excrete substantial ammonia near anemones while being cleaned. Exosymbiotic anemone shrimps thus may provide nutritional benefits to host anemones and microalgae indirectly, through their attraction of nitrogen-excreting fishes. This multi-level mutualistic network facilitates tight nutrient cycling among diverse species belonging to several phyla on coral reefs. While we assessed the rates and benefits of nutrient transfer under laboratory conditions, further research is needed to quantify the contributions of ammonia and other nutrients from client fishes through cleaner shrimps to host sea anemones in the field.
West Mata is a 1200 m deep submarine volcano where explosive boninite eruptions were observed in 2009. The acoustic signatures from the volcano's summit eruptive vents Hades and Prometheus were ...recorded with an in situ (~25 m range) hydrophone during ROV dives in May 2009 and with local (~5 km range) moored hydrophones between December 2009 and August 2011. The sensors recorded low frequency (1–40 Hz), short duration explosions consistent with magma bubble bursts from Hades, and broadband, 1–5 min duration signals associated with episodes of fragmentation degassing from Prometheus. Long‐term eruptive degassing signals, recorded through May 2010, preceded a several month period of declining activity. Degassing episodes were not recorded acoustically after early 2011, although quieter effusive eruption activity may have continued. Synchronous optical measurements of turbidity made between December 2009 and April 2010 indicate that turbidity maxima resulted from occasional south flank slope failures triggered by the collapse of accumulated debris during eruption intervals.
Key Points
Different eruption styles at summit vents observed acoustically
Intensity of explosive degassing decreased during a period of several months
Ash plumes likely originated from slope failures and not summit eruptions
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