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1.
Heart Lung Circ ; 33(4): 518-523, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38365499

RESUMEN

BACKGROUND: Blood transfusion in the perioperative cardiothoracic setting has accepted risks including deep sternal wound infection, increased intensive care unit length of stay, lung injury, and cost. It has an immunomodulatory effect which may cause allo-immunisation. This may influence long-term survival through immune-mediated factors. Targeting coagulation defects to reduce unnecessary or inappropriate transfusions may reduce these complications. METHODS: In 2012, an institution-wide patient blood management evidence-based algorithmic bleeding management protocol was implemented at The Prince Charles Hospital, Brisbane, Australia. The benefit of this has been previously reported in our lung transplant and cardiac surgery (excluding transplants) cohorts. This study aimed to investigate the effect of this on our orthotopic heart transplant recipients. RESULTS: After the implementation of the protocol, despite no difference in preoperative haemoglobin levels and higher risk patients (EuroSCORE 20 vs 26; p=0.013), the use of packed red blood cells (13.0 U vs 4.4 U; p=0.046) was significantly lower postoperatively and fresh frozen plasma was significantly lower both intra- and postoperatively (7.4 U vs 0.6 U; p<0.001, and 3.3 U vs 0.6 U; p=0.011 respectively). Concurrently, the use of prothrombin complex concentrate (33% vs 78%; p<0.001) and desmopressin (5% vs 22%; p=0.0028) was significantly higher in the post-protocol group, while there was less use of recombinant factor VIIa (15% vs 4%; p=0.058). Intraoperative units of cryoprecipitate also rose from 0.9 to 2.0 (p=0.006). CONCLUSIONS: We have demonstrated that a targeted patient blood management protocol with point-of-care testing for heart transplant recipients is correlated with fewer blood products used postoperatively, with some increase in haemostatic products and no evidence of increased adverse events.


Asunto(s)
Trasplante de Corazón , Humanos , Trasplante de Corazón/efectos adversos , Estudios Retrospectivos , Femenino , Masculino , Persona de Mediana Edad , Transfusión Sanguínea/estadística & datos numéricos , Transfusión Sanguínea/métodos , Factores de Coagulación Sanguínea/uso terapéutico , Anciano , Adulto
2.
Environ Sci Technol ; 55(23): 16246-16256, 2021 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-34797046

RESUMEN

We investigated interfacial reactions of U(VI) in the presence of Suwannee River natural organic matter (NOM) at acidic and neutral pH. Laboratory batch experiments show that the adsorption and precipitation of U(VI) in the presence of NOM occur at pH 2 and pH 4, while the aqueous complexation of U by dissolved organic matter is favored at pH 7, preventing its precipitation. Spectroscopic analyses indicate that U(VI) is mainly adsorbed to the particulate organic matter at pH 4. However, U(VI)-bearing ultrafine to nanocrystalline solids were identified at pH 4 by electron microscopy. This study shows the promotion of U(VI) precipitation by NOM at low pH which may be relevant to the formation of mineralized deposits, radioactive waste repositories, wetlands, and other U- and organic-rich environmental systems.


Asunto(s)
Residuos Radiactivos , Uranio , Adsorción , Materia Orgánica Disuelta , Concentración de Iones de Hidrógeno , Uranio/análisis
3.
Chem Geol ; 524: 345-355, 2019 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-31406388

RESUMEN

We investigated the effect of bicarbonate and oxidizing agents on uranium (U) reactivity and subsequent dissolution of U(IV) and U(VI) mineral phases in the mineralized deposits from Jackpile mine, Laguna Pueblo, New Mexico, by integrating laboratory experiments with spectroscopy, microscopy and diffraction techniques. Uranium concentration in solid samples from mineralized deposit obtained for this study exceeded 7000 mg kg-1, as determined by X-ray fluorescence (XRF). Results from X-ray photoelectron spectroscopy (XPS) suggest the coexistence of U(VI) and U(IV) at a ratio of 19:1 at the near surface region of unreacted solid samples. Analyses made using X-ray diffraction (XRD) and electron microprobe detected the presence of coffinite (USiO4) and uranium-phosphorous-potassium (U-P-K) mineral phases. Imaging, mapping and spectroscopy results from scanning transmission electron microscopy (STEM) indicate that the U-P-K phases were encapsulated by carbon. Despite exposing the solid samples to strong oxidizing conditions, the highest aqueous U concentrations were measured from samples reacted with 100% air saturated 10 mM NaHCO3 solution, at pH 7.5. Analyses using X-ray absorption spectroscopy (XAS) indicate that all the U(IV) in these solid samples were oxidized to U(VI) after reaction with dissolved oxygen and hypochlorite (OCl-) in the presence of bicarbonate (HCO3 -). The reaction between these organic rich deposits, and 100% air saturated bicarbonate solution (containing dissolved oxygen), can result in considerable mobilization of U in water, which has relevance to the U concentrations observed at the Rio Paguate across the Jackpile mine. Results from this investigation provide insights on the reactivity of carbon encapsulated U-phases under mild and strong oxidizing conditions that have important implication in U recovery, remediation and risk exposure assessment of sites.

4.
Water Res ; 58: 102-10, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24747141

RESUMEN

Advanced treatment to remove trace constituents and emerging contaminants is an important consideration for wastewater treatment for potable reuse, and reverse osmosis (RO) can be a suitable technology to provide the necessary level of treatment. However, membrane fouling by biological and organic matter is a concern. This research examined the development of the RO membrane fouling layer using a bench-scale membrane bioreactor operating at different solids retention times (SRTs), followed by a custom-designed RO test cell. The RO test cell contained stacked plates that sandwich five sheets of RO membrane material, which can be extracted for autopsy at separate times over the course of an experiment without disturbing the remaining membranes. The MBR-RO system was run continuously for 2 weeks at each SRT. The RO membranes were stained for live and dead cells, protein, and carbohydrate-like materials, and visualized using confocal laser scanning microscopy. Images of the stained foulant layers were obtained at different depths within the foulant layer at each time point for all SRT conditions. As the RO foulant layer developed, changes occurred in the distribution and morphology of the live cells and carbohydrates, but not the proteins. These trends were similar for all three SRT conditions tested. RO membrane fouling increased with increased MBR SRT, and the highest SRT had the highest ratios of live to dead cells and carbohydrate-like material to dead cells. The autopsied membranes were also analyzed for protein and carbohydrate content, and it was found that the carbohydrate concentration on the membranes after 14 days increased as the SRT increased.


Asunto(s)
Eliminación de Residuos Líquidos/métodos , Purificación del Agua/instrumentación , Purificación del Agua/métodos , Incrustaciones Biológicas , Carbohidratos/química , Análisis de Falla de Equipo , Membranas Artificiales , Microscopía Confocal , Ósmosis , Proteínas/química , Eliminación de Residuos Líquidos/instrumentación , Aguas Residuales
5.
Water Res ; 49: 53-61, 2014 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-24316181

RESUMEN

The effect of the solids retention time (SRT) in a membrane bioreactor (MBR) on the fouling of the membranes in a subsequent reverse osmosis (RO) process used for wastewater reuse was studied experimentally using a pilot-scale treatment system. The MBR-RO pilot system was fed effluent from the primary clarifiers at a large municipal wastewater treatment plant. The SRT in the MBRs was adjusted to approximately 2, 10, and 20 days in three experiments. The normalized specific flux through the MBR and RO membranes was evaluated along with inorganic and organic constituents in the influent and effluent of each process. Increasing the SRT in the MBR led to an increase in the removal of bulk DOC, protein, and carbohydrates, as has been observed in previous studies. Increasing the SRT led to a decrease in the fouling of the MBR membranes, which is consistent with previous studies. However, the opposite trend was observed for fouling of the RO membranes; increasing the SRT of the MBR resulted in increased fouling of the RO membranes. These results indicate that the constituents that foul MBR membranes are not the same as those that foul RO membranes; to be an RO membrane foulant in a MBR-RO system, the constituents must first pass through the MBR membranes without being retained. Thus, an intermediate value of SRT may be best choice of operating conditions in an MBR when the MBR is followed by RO for wastewater reuse.


Asunto(s)
Incrustaciones Biológicas , Reactores Biológicos , Ósmosis , Reciclaje , Aguas del Alcantarillado/química , Aguas Residuales/química , Purificación del Agua/instrumentación , Carbohidratos/análisis , Carbono/análisis , Membranas Artificiales , Compuestos Orgánicos/aislamiento & purificación , Proyectos Piloto , Proteínas/análisis , Factores de Tiempo , Eliminación de Residuos Líquidos , Calidad del Agua
6.
Environ Geochem Health ; 36(3): 477-87, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24135898

RESUMEN

The objectives of the study are to present a critical review of the (238)U, (234)U, (235)U, (226)Ra and (210)Pb levels in water samples from the EPA studies (U.S. EPA in Abandoned uranium mines and the Navajo Nation: Red Valley chapter screening assessment report. Region 9 Superfund Program, San Francisco, 2004, Abandoned uranium mines and the Navajo Nation: Northern aum region screening assessment report. Region 9 Superfund Program, San Francisco, 2006, Health and environmental impacts of uranium contamination, 5-year plan. Region 9 Superfund Program, San Franciso, 2008) and the dose assessment for the population due to ingestion of water containing (238)U and (234)U. The water quality data were taken from Sect. "Data analysis" of the published report, titled Abandoned Uranium Mines Project Arizona, New Mexico, Utah-Navajo Lands 1994-2000, Project Atlas. Total uranium concentration was above the maximum concentration level for drinking water (7.410-1 Bq/L) in 19 % of the water samples, while (238)U and (234)U concentrations were above in 14 and 17 % of the water samples, respectively. (226)Ra and (210)Pb concentrations in water samples were in the range of 3.7 × 10(-1) to 5.55 × 102 Bq/L and 1.11 to 4.33 × 102 Bq/L, respectively. For only two samples, the (226)Ra concentrations exceeded the MCL for total Ra for drinking water (0.185 Bq/L). However, the (210)Pb/(226)Ra ratios varied from 0.11 to 47.00, and ratios above 1.00 were observed in 71 % of the samples. Secular equilibrium of the natural uranium series was not observed in the data record for most of the water samples. Moreover, the (235)U/(total)U mass ratios ranged from 0.06 to 5.9 %, and the natural mass ratio of (235)U to (total)U (0.72 %) was observed in only 16 % of the water samples, ratios above or below the natural ratio could not be explained based on data reported by U.S. EPA. In addition, statistical evaluations showed no correlations among the distribution of the radionuclide concentrations in the majority of the water samples, indicating more than one source of contamination could contribute to the sampled sources. The effective doses due to ingestion of the minimum uranium concentrations in water samples exceed the average dose considering inhalation and ingestion of regular diet for other populations around the world (1 µSv/year). The maximum doses due to ingestion of (238)U or (234)U were above the international limit for effective dose for members of the public (1 mSv/year), except for inhabitants of two chapters. The highest effective dose was estimated for inhabitants of Cove, and it was almost 20 times the international limit for members of the public. These results indicate that ingestion of water from some of the sampled sources poses health risks.


Asunto(s)
Agua Subterránea/química , Radioisótopos de Plomo/análisis , Minería , Radio (Elemento)/análisis , Uranio/análisis , Contaminantes Radiactivos del Agua/análisis , Arizona , Estados Unidos , United States Environmental Protection Agency
7.
Pulm Circ ; 2(3): 359-64, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23130104

RESUMEN

The objective of this study was to report the outcome of pulmonary endarterectomy (PEA) surgery performed for chronic thromboembolic pulmonary hypertension (CTEPH) at a single tertiary center. The prospective study consisted of 35 patients with surgically amenable CTEPH undergoing PEA between September 2004 and September 2010. The main outcome measures were Functional (New York Heart Association [NYHA] class, 6-Minute Walk Distance), hemodynamic (echocardiography, right heart catheterization, and cardiac MRI), and outcome data (morbidity and mortality). Following PEA, there were significant improvements in NYHA class (pre 2.9±0.7 vs. post 1.3±0.5, P < 0.0001), right ventricular systolic pressure (pre 77.4±24.8 mmHg vs. post 45.1±24.9 mmHg, P = 0.0005), 6-Minute Walk Distance (pre 419.6±109.4 m vs. post 521.6±83.5 m, P = 0.0017), mean pulmonary artery pressure (pre 41.8±15.3 mmHg vs. post 24.7±8.8 mmHg, P = 0.0006), and cardiac MRI indices (end diastolic volume pre 213.8±49.2 mL vs. post 148.1±34.5 mL, P < 0.0001; ejection fraction pre 40.7±9.8 mL vs. post 48.1±8.9 mL, P = 0.0069). The mean cardiopulmonary bypass time was 258.77±26.16 min, with a mean circulatory arrest time of 43.83±28.78 min, a mean ventilation time of 4.7±7.93 days (range 0.2-32.7), and a mean intensive care unit stay of 7.22±8.71 days (range 1.1-33.8). Complications included reperfusion lung injury (20%), persistent pulmonary hypertension (17.1%), slow respiratory wean (25.7%), pericardial effusion (11.4%), and cardiac tamponade (5.7%). 1-year mortality post-procedure was 11.4%. Pulmonary endarterectomy can be performed safely with relatively low mortality.

8.
Water Res ; 46(4): 1005-14, 2012 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-22202904

RESUMEN

This pilot-scale research project investigated and compared the removal of pharmaceuticals and personal care products (PPCPs) and other micropollutants from treated wastewater by ozone/biofiltration and reverse osmosis (RO). The reduction in UV254 absorbance as a function of ozone dose correlated well with the reduction in nonbiodegradable dissolved organic carbon and simultaneous production of biodegradable dissolved organic carbon (BDOC). BDOC analyses demonstrated that ozone does not mineralize organics in treated wastewater and that biofiltration can remove the organic oxidation products of ozonation. Biofiltration is recommended for treatment of ozone contactor effluent to minimize the presence of unknown micropollutant oxidation products in the treated water. Ozone/biofiltration and RO were compared on the basis of micropollutant removal efficiency, energy consumption, and waste production. Ozone doses of 4-8 mg/L were nearly as effective as RO for removing micropollutants. When wider environmental impacts such as energy consumption, water recovery, and waste production are considered, ozone/biofiltration may be a more desirable process than RO for removing PPCPs and other trace organics from treated wastewater.


Asunto(s)
Cosméticos/aislamiento & purificación , Filtración/métodos , Ósmosis , Ozono/química , Preparaciones Farmacéuticas/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Biodegradación Ambiental , Reactores Biológicos , Carbono/aislamiento & purificación , Límite de Detección , Membranas Artificiales , Compuestos Orgánicos/aislamiento & purificación , Termodinámica , Eliminación de Residuos Líquidos
9.
J Thorac Cardiovasc Surg ; 141(2): 383-7, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20471039

RESUMEN

OBJECTIVE: Pulmonary endarterectomy is the treatment of choice for chronic thromboembolic pulmonary hypertension. In many patients hemodynamics are normalized early after surgical intervention. However, the effect of residual pulmonary hypertension on postoperative clinical status and survival is unknown. METHODS: Data were collected prospectively on all patients who underwent pulmonary endarterectomy in a continuous national series between 1997 and December 2007. Postoperatively, patients underwent scheduled reinvestigation, including functional testing and right heart catheterization, at 3 months after the operation. They were divided into 2 groups based on mean pulmonary artery pressure: group 1, less than 30 mm Hg; group 2, 30 mm Hg or greater. RESULTS: Three hundred fourteen patients underwent pulmonary endarterectomy, survived to hospital discharge, and completed the 3-month follow-up period. At 3 months after pulmonary endarterectomy, there was a significant reduction in mean pulmonary artery pressure for the whole cohort (48±12 to 26±10 mm Hg, P<.001). However, 31% of the patients had residual pulmonary hypertension. Group 1 patients enjoyed significantly better exercise capacity and improved symptoms compared with group 2 patients. In addition, there were significantly fewer patients receiving targeted medical therapy in group 1 versus group 2 (0% vs 25%, P<.001). Conditional survival after discharge from the hospital for the whole cohort was 90.0% at 5 years and was not different between groups (90.3% for group 1 vs 89.9% for group 2, P=.36). CONCLUSIONS: For patients undergoing pulmonary endarterectomy, survival after hospital discharge is excellent. Residual pulmonary hypertension significantly compromised symptom status and functional capacity but did not appear to adversely affect medium-term survival. The effect of targeted medical therapy in patients with residual pulmonary hypertension after pulmonary endarterectomy needs to be evaluated further.


Asunto(s)
Endarterectomía/mortalidad , Hipertensión Pulmonar/cirugía , Arteria Pulmonar/cirugía , Trombectomía/mortalidad , Tromboembolia/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antihipertensivos/uso terapéutico , Presión Sanguínea , Distribución de Chi-Cuadrado , Enfermedad Crónica , Inglaterra , Tolerancia al Ejercicio , Femenino , Humanos , Hipertensión Pulmonar/etiología , Hipertensión Pulmonar/mortalidad , Hipertensión Pulmonar/fisiopatología , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Arteria Pulmonar/fisiopatología , Medición de Riesgo , Factores de Riesgo , Tasa de Supervivencia , Tromboembolia/complicaciones , Tromboembolia/mortalidad , Tromboembolia/fisiopatología , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
10.
Eur J Cardiothorac Surg ; 34(3): 525-9; discussion 529-30, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18501623

RESUMEN

OBJECTIVE: Chronic thromboembolic pulmonary hypertension (CTEPH) results in severe symptoms and impaired survival. Pulmonary thromboendarterectomy (PTE) is considered the gold standard treatment. Many units have reported excellent early results post PTE, but there is less information on whether benefit is sustained. We sought to determine the medium-term functional and haemodynamic outcome for patients following PTE and the longer-term survival after discharge from hospital. METHODS: Data were collected prospectively on all patients who underwent PTE in the UK between 1997 and June 2006. Patients were reassessed at 3 and 12 months after operation. Follow-up over time was assessed using repeated measures ANOVA, the Friedman test or Wilcoxon signed ranks test as appropriate. RESULTS: Two hundred and twenty-nine patients underwent PTE, survived to hospital discharge, and completed follow-up. At 3 months following operation, there was a significant reduction in mean pulmonary artery pressure (47+/-14 to 25+/-14mmHg, p<0.001), a significant increase in cardiac index (1.9+/-0.7 to 2.5+/-0.6l/minm(2), p<0.001) and a significant increase in 6-min walk distance (269+/-123 to 375+/-104m, p<0.001). At 12-month follow-up, the haemodynamic improvements were sustained and there was a further increase in 6-min walk distance (375+/-104 to 392+/-108m, p=0.004). NYHA class was significantly reduced at 3 months, with the improvement sustained at 12 months. Conditional survival following discharge from hospital was 92.5% at 5 years and 88.3% at 10 years. CONCLUSIONS: PTE is a very effective therapy for CTEPH. This is the first report from a continuous national series to fully characterise haemodynamic and functional outcome 1 year after PTE. Patients enjoy continued improvement in haemodynamic status that translates into better exercise capacity, reduced symptoms and excellent survival.


Asunto(s)
Endarterectomía/métodos , Hipertensión Pulmonar/cirugía , Arteria Pulmonar/cirugía , Embolia Pulmonar/cirugía , Presión Sanguínea/fisiología , Gasto Cardíaco , Enfermedad Crónica , Métodos Epidemiológicos , Prueba de Esfuerzo/métodos , Femenino , Humanos , Hipertensión Pulmonar/etiología , Hipertensión Pulmonar/fisiopatología , Masculino , Persona de Mediana Edad , Arteria Pulmonar/fisiopatología , Embolia Pulmonar/complicaciones , Embolia Pulmonar/fisiopatología , Resultado del Tratamiento
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