Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
1.
J Vasc Surg Venous Lymphat Disord ; 12(3): 101856, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38551528

RESUMO

OBJECTIVE: The objective of this study is to systemically review the literature on Anterior Saphenous Vein (ASV) reflux treatment and insurance impediments to treatment coverage. METHODS: A literature search was performed using a PRISMA framework. In addition, a cross-sectional analysis of insurance policies for ASV treatment was evaluated. RESULTS: Published evidence and treatment considerations in the literature for ASV treatment are discussed. In 155 of 226 (68.6%) insurance policies reviewed coverage of ASV ablation was allowed while 62/226 (27.4%) did not specify coverage and 9/226 (4.0%) specified ASV treatment was not covered. Of the 155 that provide ASV coverage, 98 (62.2%) provide coverage with criteria such as requiring prior treatment of the great saphenous vein. CONCLUSIONS: Vein treatment experts should continue to advocate to insurance carriers to update their varicose vein treatment policies to reflect the substantial clinical evidence so that patients with ASV reflux can be appropriately treated.

2.
J Vasc Surg Venous Lymphat Disord ; 12(3): 101857, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38551526

RESUMO

BACKGROUND: The decision to treat a refluxing anterior saphenous vein (ASV) should be a clinical decision based on the assessment on the ASV's contribution to patient's signs and symptoms. Once the decision to treat has been made, there are anatomic, clinical, and technical considerations in treatment planning. METHODS: Clinical scenarios were discussed by a panel of experts and common anatomic, clinical, and technical considerations were identified. RESULTS: There are unique clinical considerations such as whether both the great saphenous vein (GSV) and ASV should be concomitantly treated, if a normal ASV should be treated when treating a refluxing GSV and when and how to treat the associated tributary varicose tributaries. Being aware of the anatomic, clinical, and technical considerations allows development of a treatment plan that optimizes long-term outcomes in patients with ASV reflux. CONCLUSIONS: Ultimately the treatment plan should be tailored to address these types of variables in a patient-centered discussion.


Assuntos
Varizes , Insuficiência Venosa , Humanos , Estados Unidos , Veia Safena , Varizes/terapia , Insuficiência Venosa/terapia , Resultado do Tratamento , Veia Femoral
3.
J Vasc Surg Venous Lymphat Disord ; 12(3): 101855, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38551527

RESUMO

BACKGROUND: The term Anterior Accessory of the Great Saphenous Vein suggests this is a branch tributary vein despite this vessel's anatomic features of a truncal vein. A multisocietal group suggested to designate this the anterior saphenous vein (ASV). This study was aimed to evaluate its ultrasound anatomy in normal and varicose limbs. METHODS: The clinical anatomy of the ASV was evaluated by narrative review of the literature. Additionally, the course of the ASV was evaluated in 62 limbs with no evidence of venous disease and 62 limbs with varicosities. RESULTS: The ASV length, patterns of origin and termination are reported in both normal and patients with varicose veins. Discussion of the patterns is supported by the narrative review of the literature. CONCLUSIONS: The ASV must be considered a truncal vein and its treatment modalities should be the same that for the great and small saphenous veins rather than a tributary vein.


Assuntos
Varizes , Insuficiência Venosa , Humanos , Estados Unidos , Veia Safena/diagnóstico por imagem , Varizes/terapia , Veia Femoral , Veia Poplítea , Ultrassonografia Doppler Dupla , Insuficiência Venosa/terapia , Resultado do Tratamento
4.
Innovations (Phila) ; 19(2): 143-149, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38504149

RESUMO

OBJECTIVE: This study evaluated the efficacy of the Minimally Invasive Targeted Resection (MiTR) device, a novel electrosurgical instrument that allows for targeted excision of a lung abnormality while using bipolar radiofrequency (RF) energy to seal blood vessels and airways. METHODS: The MiTR system was evaluated in 7 acute and 2 chronic porcine (7-day) models to evaluate the efficacy of tissue excision with bipolar RF sealing of blood vessels and airways and application of an autologous blood patch into the excised tissue cavity. Air leak was recorded for all evaluations. The study was approved by the institutional ethical board. RESULTS: Nineteen lung tissue samples, measuring 2.5 cm long × 1.2 cm diameter, were excised. In 8 of 9 animals (89%), hemostasis and pneumostasis were observed visually at the completion of the procedure. In 2 of 2 chronic animals (100%), hemostasis and pneumostasis persisted for the 7-day observation period. Histologic examination of the excised samples showed preservation of the core parenchymal architecture without evident tissue damage of the samples that would impair pathologic analysis. CONCLUSIONS: Percutaneous resection of targeted lung tissue with the MiTR system demonstrated hemostasis and pneumostasis while obtaining a histologically intact sample. After regulatory approval, the use of this device could offer more tissue for analysis than a transthoracic needle biopsy or bronchoscopy and a far less invasive alternative to video-assisted thoracic surgery or thoracotomy. This may also expand patient and physician options for the early diagnosis and treatment of lung cancer.


Assuntos
Pulmão , Animais , Suínos , Pulmão/cirurgia , Pulmão/patologia , Pneumonectomia/instrumentação , Pneumonectomia/métodos , Eletrocirurgia/instrumentação , Eletrocirurgia/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Hemostasia Cirúrgica/instrumentação , Hemostasia Cirúrgica/métodos , Cirurgia Assistida por Computador/métodos , Cirurgia Assistida por Computador/instrumentação
5.
J Vasc Surg Venous Lymphat Disord ; 12(3): 101721, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38008181

RESUMO

BACKGROUND: There is a lack of clarity regarding the terminology of the anterior accessory saphenous vein (AASV) that can impact treatment outcomes. Although use of the word "accessory" implies that the vein is a superficial tributary, evidence supports its role as a truncal vein, similar to the great and small saphenous veins, and warranting a change in terminology. METHODS: A multisocietal panel was convened by the American Vein and Lymphatic Society (AVLS), the Union International of Phlebology (UIP), and the American Venous Forum (AVF). The group was charged with reviewing the existing anatomic and clinical literature pertaining to the term "anterior accessory saphenous vein" and to consider the need for alternative terminology. CONCLUSIONS: Based on the insights gathered from the literature review and extensive discussions, the panel recommends changing the terminology such that the "anterior accessory saphenous vein" (AASV) now be designated the anterior saphenous vein (ASV).


Assuntos
Varizes , Insuficiência Venosa , Humanos , Estados Unidos , Veia Safena , Varizes/terapia , Veia Femoral , Resultado do Tratamento , Insuficiência Venosa/terapia
6.
J Cardiothorac Surg ; 17(1): 298, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36476289

RESUMO

BACKGROUND: Pleural effusions commonly occur in patients recovering from cardiac surgery; however, the impact on outcomes is not well characterized. The purpose of this study is to characterize the clinical outcomes of cardiac surgery patients with pleural effusion. METHODS: All patients undergoing cardiac surgery between 2006 and 2019 at a tertiary care university hospital were included in this observational, cross-sectional analysis using propensity matching. RESULTS: Of 11,037 patients that underwent cardiac surgery during the study period, 6461 (58.5%) had no pleural effusion (Group 0), 3322 (30.1%) had pleural effusion only (Group 1), and 1254 (11.4%) required at least one secondary drainage procedure after the index operation (Group 2). After propensity matching, the mortality of patients who underwent secondary drainage procedures was 6.1% higher than in Group 1 (p < 0.001). Intensive care unit (ICU) stay was longer for those with pleural effusions (18 [IQR 9-32] days in Group 2, 10 [IQR 6-17] days for Group 1, and 7 [IQR 4-11] days for Group 0, p < 0.001). Patients with pleural effusions had a higher incidence of hemodialysis (246 [20.0%] in Group 2, 137 [11.1%] in Group 1, 98 [7.98%] in Group 0), and a longer ventilation time in the ICU (57 [IQR 21.0-224.0] hours in Group 2, 25.0 [IQR 14.0-58.0] hours in Group 1, 16.0 [IQR 10.0-29.0] hours in Group 0). CONCLUSION: Pleural effusions, especially those that require a secondary drainage procedure during recovery, are associated with significantly worse outcomes including increased mortality, longer length of stay, and higher complication rates. These insights may be of great interest to scientists, clinicians, and industry leaders alike to foster research into innovative methods for preventing and treating pleural effusions with the aim of improving outcomes for patients recovering from cardiac surgery.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Derrame Pleural , Humanos , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Estudos Transversais , Período Pós-Operatório
7.
World J Surg ; 45(4): 917-925, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33521878

RESUMO

BACKGROUND: Despite the emergence of Enhanced Recovery Protocols (ERPs) in cardiac surgery, there is no consensus on the essential elements for data reporting for quality improvement efforts, as well as accountability and standardization of outcome reporting across institutions. The aim of this study was to establish a consensus on essential data elements for cardiac ERAS®. METHODS: A 2-round modified Delphi technique was utilized based on existing recommendations from the recently published ERAS® cardiac surgery consensus guidelines. Round 1 included a steering committee of 10 experts who oversaw formulation of a focused list of data elements into 3 main areas: Preoperative, intraoperative and postoperative. Round 2 consisted of a multidisciplinary, multinational, heterogenous group of 50 voting experts from across the United States and Europe. All participants evaluated their level of agreement with each data element using a 5-point Likert scale with consensus threshold of 70%. RESULTS: In round 1, 17 data elements were considered essential (consensus > = 70%, either positive or negative) and 6 were considered marginal (consensus < = 70%, either positive or negative). In round 2, positive consensus was achieved for 15/17 (88.2%) data elements in the essential category, and all six data elements (100%) in the marginal category, indicating a high level of overall agreement. CONCLUSION: This initial study, which identified 21 key data elements for collection in an ERAS® cardiac program, will aid clinicians in establishing a framework for evaluating the quality of their contemporary ERP processes and will allow acquisition of data to help benchmark performance metrics between hospitals.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Consenso , Técnica Delphi , Europa (Continente) , Humanos , Período Pós-Operatório
10.
J Cardiothorac Surg ; 14(1): 192, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703606

RESUMO

BACKGROUND: Chest tubes are routinely used to evacuate shed mediastinal blood in the critical care setting in the early hours after heart surgery. Inadequate evacuation of shed mediastinal blood due to chest tube clogging may result in retained blood around the heart and lungs after cardiac surgery. The objective of this study was to compare if active chest tube clearance reduces the incidence of retained blood complications and associated hospital resource utilization after cardiac surgery. METHODS: Propensity matched analysis of 697 consecutive patients who underwent cardiac surgery at a single center. 302 patients served as a baseline control (Phase 0), 58 patients in a training and compliance verification period (Phase 1) and 337 were treated prospectively using active tube clearance (Phase 2). The need to drain retained blood, pleural effusions, postoperative atrial fibrillation, ICU resource utilization and hospital costs were assessed. RESULTS: Propensity matched patients in Phase 2 had a reduced need for drainage procedures for pleural effusions (22% vs. 8.1%, p < 0.001) and reduced postoperative atrial fibrillation (37 to 25%, P = 0.011). This corresponded with fewer hours in the ICU (43.5 [24-79] vs 30 [24-49], p = < 0.001), reduced median postoperative length of stay (6 [4-8] vs 5 [4-6.25], p < 0.001) median costs reduced by $1831.45 (- 3580.52;82.38, p = 0.04) and the mean costs reduced by an average of $2696 (- 6027.59;880.93, 0.116). CONCLUSIONS: This evidence supports the concept that efforts to actively maintain chest tube patency in early recovery is useful in improving outcomes and reducing resource utilization and costs after cardiac surgery. TRIAL REGISTRATION: Clinicaltrial.gov, NCT02145858, Registered: May 23, 2014.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Tubos Torácicos , Drenagem/métodos , Custos Hospitalares/estatística & dados numéricos , Complicações Pós-Operatórias/prevenção & controle , Idoso , Drenagem/economia , Drenagem/instrumentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , New Hampshire , Complicações Pós-Operatórias/economia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Pontuação de Propensão , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento
11.
J Vasc Surg Cases Innov Tech ; 5(3): 372-374, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31440717

RESUMO

The VenaSeal (Medtronic, Minneapolis, Minn) cyanoacrylate closure system is a nonthermal technique for ablating saphenous veins using a proprietary n-butyl cyanoacrylate. One possible side effect is an allergic reaction to cyanoacrylate. We report the case of a 49-year-old woman treated with cyanoacrylate closure who developed a persistent type IV hypersensitivity reaction. The patient elected to have the vein excised, and the histologic features were consistent with a type IV hypersensitivity reaction.

12.
JAMA Surg ; 154(8): 755-766, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31054241

RESUMO

Enhanced Recovery After Surgery (ERAS) evidence-based protocols for perioperative care can lead to improvements in clinical outcomes and cost savings. This article aims to present consensus recommendations for the optimal perioperative management of patients undergoing cardiac surgery. A review of meta-analyses, randomized clinical trials, large nonrandomized studies, and reviews was conducted for each protocol element. The quality of the evidence was graded and used to form consensus recommendations for each topic. Development of these recommendations was endorsed by the Enhanced Recovery After Surgery Society.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Consenso , Recuperação Pós-Cirúrgica Melhorada/normas , Assistência Perioperatória/normas , Guias de Prática Clínica como Assunto , Humanos
13.
Ann Thorac Surg ; 105(1): 321-328, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29174782

RESUMO

BACKGROUND: Prevention strategies have long been sought to reduce the incidence and burden of postoperative atrial fibrillation (POAF) after heart surgery. However, none has emerged as a dominant and widely applicable prophylactic measure. The purpose of this review is to consider the biological mechanisms by which shed mediastinal blood leads to oxidation and inflammation within the postoperative pericardial environment and how this might trigger POAF in susceptible persons, as well as how it could represent a new target for prevention of POAF. METHODS: We conducted a structured research of literature using PubMed and MEDLINE databases to May 2016. Biomolecular and clinical articles focused on assessing the contribution of pericardial blood, or the resulting inflammation within the pericardial space and its potential role in triggering POAF, were included in this review. RESULTS: Evidence suggests that shed mediastinal blood through breakdown products, activation of coagulation cascade, and oxidative burst contributes to a highly pro-oxidant and proinflammatory milieu found within the pericardial space that can trigger postoperative atrial fibrillation in susceptible persons. The extent of this reaction could be blunted by reducing the exposition of pericardium to blood either through posterior pericardiotomy or improved chest drainage. CONCLUSIONS: Shed mediastinal blood undergoing transformation within the pericardium appears to be an important contributing factor to POAF. Strategies to prevent shed mediastinal blood from pooling around the heart might be considered in developing future paradigms for prevention of POAF.


Assuntos
Fibrilação Atrial/etiologia , Sangue , Procedimentos Cirúrgicos Cardíacos , Pericárdio , Complicações Pós-Operatórias/etiologia , Fibrilação Atrial/prevenção & controle , Fenômenos Fisiológicos Sanguíneos , Humanos , Mediastino , Complicações Pós-Operatórias/prevenção & controle
15.
J Thorac Cardiovasc Surg ; 152(2): 595-601.e4, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27210474

RESUMO

OBJECTIVES: Evacuation of shed blood from around the heart and lungs is a critical requirement for patients in early recovery after cardiac surgery. Incomplete evacuation of shed blood can result in retained blood, which may require subsequent reinterventions to facilitate recovery. The purpose of this study was to determine the incidence of retained blood requiring reintervention and examine the impact on outcomes. METHODS: We performed a cross-sectional, observational study of all adult patients undergoing cardiac surgery between 2006 and 2013. Subjects who required an intervention to remove blood, blood clot, or bloodily fluid were attributed to the retained blood group. These patients were compared with those not presenting with any of the defined criteria for retained blood. Multivariate regression was performed to account for confounders. RESULTS: Of 6909 adult patients who underwent cardiac surgery, 1316 (19%) presented with a retained blood-related condition. Retained blood was associated with increased in-hospital mortality (odds ratio [OR], 4.041; 95% confidence interval [CI], 2.589-6.351, P < .001) and a length of stay more than 13 days in the hospital (OR, 3.853; 95% CI, 2.882-5.206; P < .001) and 5 days in the intensive care unit (OR, 4.602; 95% CI, 3.449-6.183; P < .001). The OR for a time of ventilation greater than 23 hours was 3.596 (95% CI, 2.690-4.851; P < .001) and for incidence of renal replacement therapy was 4.449 (95% CI, 3.188-6.226; P < .001). CONCLUSIONS: Postoperative retained blood is a common outcome and associated with higher in-hospital mortality, longer intensive care unit and hospital stay, and higher incidence of renal replacement therapy. Further research is needed to validate these results and explore interventions to reduce these complications.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Drenagem/efeitos adversos , Hemorragia Pós-Operatória/terapia , Idoso , Procedimentos Cirúrgicos Cardíacos/mortalidade , Tubos Torácicos , Distribuição de Qui-Quadrado , Estudos Transversais , Bases de Dados Factuais , Drenagem/instrumentação , Drenagem/mortalidade , Feminino , Mortalidade Hospitalar , Humanos , Tempo de Internação , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Hemorragia Pós-Operatória/sangue , Hemorragia Pós-Operatória/diagnóstico , Hemorragia Pós-Operatória/mortalidade , Terapia de Substituição Renal , Respiração Artificial , Retratamento , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
16.
Innovations (Phila) ; 10(5): 296-303, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26575376

RESUMO

Retained blood occurs when drainage systems fail to adequately evacuate blood during recovery from cardiothoracic surgery. As a result, a spectrum of mechanical and inflammatory complications can ensue in the acute, subacute, and chronic setting. The objectives of this review were to define the clinical syndrome associated with retained blood over the spectrum of recovery and to review existing literature regarding how this may lead to complications and contributes to poor outcomes. To better understand and prevent this constellation of clinical complications, a literature review was conducted, which led us to create a new label that better defines the clinical entity we have titled retained blood syndrome. Analysis of published reports revealed that 13.8% to 22.7% of cardiac surgical patients develop one or more components of retained blood syndrome. This can present in the acute, subacute, or chronic setting, with different pathophysiologic mechanisms active at different times. The development of retained blood syndrome has been linked to other clinical outcomes, including the development of postoperative atrial fibrillation and infection and the need for hospital readmission. Grouping multiple objectively measurable and potentially preventable postoperative complications that share a common etiology of retained blood over the continuum of recovery demonstrates a high prevalence of retained blood syndrome. This suggests the need to develop, implement, and test clinical strategies to enhance surgical drainage and reduce postoperative complications in patients undergoing cardiothoracic surgery.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Complicações Pós-Operatórias/etiologia , Perda Sanguínea Cirúrgica , Drenagem/efeitos adversos , Humanos , Complicações Pós-Operatórias/prevenção & controle , Síndrome , Falha de Tratamento
17.
Proc Natl Acad Sci U S A ; 111(47): 16654-61, 2014 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-25349389

RESUMO

Until recently, hydrothermal vents were not considered to be an important source to the marine dissolved Fe (dFe) inventory because hydrothermal Fe was believed to precipitate quantitatively near the vent site. Based on recent abyssal dFe enrichments near hydrothermal vents, however, the leaky vent hypothesis [Toner BM, et al. (2012) Oceanography 25(1):209-212] argues that some hydrothermal Fe persists in the dissolved phase and contributes a significant flux of dFe to the global ocean. We show here the first, to our knowledge, dFe (<0.4 µm) measurements from the abyssal southeast and southwest Pacific Ocean, where dFe of 1.0-1.5 nmol/kg near 2,000 m depth (0.4-0.9 nmol/kg above typical deep-sea dFe concentrations) was determined to be hydrothermally derived based on its correlation with primordial (3)He and dissolved Mn (dFe:(3)He of 0.9-2.7 × 10(6)). Given the known sites of hydrothermal venting in these regions, this dFe must have been transported thousands of kilometers away from its vent site to reach our sampling stations. Additionally, changes in the size partitioning of the hydrothermal dFe between soluble (<0.02 µm) and colloidal (0.02-0.4 µm) phases with increasing distance from the vents indicate that dFe transformations continue to occur far from the vent source. This study confirms that although the southern East Pacific Rise only leaks 0.02-1% of total Fe vented into the abyssal Pacific, this dFe persists thousands of kilometers away from the vent source with sufficient magnitude that hydrothermal vents can have far-field effects on global dFe distributions and inventories (≥3% of global aerosol dFe input).

18.
Sci Total Environ ; 491-492: 148-53, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-24444513

RESUMO

Surficial sediment samples were obtained from 25 locations within Kuwait Bay and outside the Bay, in the Northwestern Arabian Gulf, to access recent pollution in Kuwait. The historical deposition of PBDEs to this portion of the Arabian Gulf was reconstructed by collecting a sediment core at the entrance of Kuwait Bay. The mean (and range) in concentrations of ∑11PBDEs in surficial sediments was 0.164±0.09 (0.06-0.44) pg/g dw. The concentrations measured in Kuwait Bay were generally higher than those measured in the open Gulf. When the concentrations were normalized to organic carbon, the average ∑11PBDEs concentrations measured in Kuwait Bay were seven times higher than average concentrations outside the Bay. The historical record, reconstructed from a sediment core collected at the entrance of Kuwait Bay, showed that Σ11PBDE concentrations were generally low in deeper sediment sections. The concentrations started to increase above background in the mid-1950s and increased sharply to a maximum Σ11PBDE concentration of ca 1,100 pg/g in the late 1980s. Concentrations decreased thereafter until another pulse in concentrations was observed around the early 2000 followed by a decrease in subsequent years. It is likely that the initial pulse in concentration recorded in sediments is related to inputs from the Gulf war of 1991. The penta congeners were observed throughout the length of the core although the concentrations were low. The congeners present in the Deca-PBDE technical mixture, particularly BDE 209 which is the main congener in the Deca-BDE mixture, occurred in sediment cores around the 1980s, and the concentrations increased rapidly thereafter being the most dominant congener since their first detection in sediments. The presence of nona-BDE congeners in proportions exceeding those in commercial mixtures may be suggestive of debromination of BDE 209 in sediments.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Éteres Difenil Halogenados/análise , Poluentes Químicos da Água/análise , Kuweit , Água do Mar/química , Análise Espaço-Temporal , Poluição Química da Água/estatística & dados numéricos
20.
Anal Chem ; 85(9): 4357-62, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23544623

RESUMO

Organic ligands dominate the speciation of iron in the ocean. Little is known, however, about the chemical composition and distribution of these compounds. Here, we describe a method to detect low concentrations of organic Fe ligands using reverse-phase high-performance liquid chromatography (HPLC) tandem multicollector inductively coupled plasma mass spectrometry. This technique can be used to screen seawater and marine cultures for target compounds that can be isolated and structurally characterized. Sensitive detection (<1 picomole Fe) is achieved using an iron-free HPLC system to reduce background Fe levels, minimizing (40)Ar(16)O(+) interferences on (56)Fe with a hexapole collision cell, and introducing oxygen into the sample carrier gas to prevent the formation of reduced carbon deposits that decrease sensitivity. This method was tested with a chromatographic separation of five trace metal complexes that represent the polarity range likely found in seawater. Good separation was achieved with a 20 min water/methanol gradient, although sensitivity decreased by a factor of 2 at high organic solvent concentrations. Finally, Fe ligand complexes were detected from the organic extract of surface South Pacific seawater and from culture media of the siderophore producing cyanobacteria Synechococcus sp. PCC 7002.


Assuntos
Compostos Férricos/análise , Água do Mar/química , Synechococcus/química , Cromatografia Líquida de Alta Pressão , Ligantes , Espectrometria de Massas , Espectrofotometria Atômica , Synechococcus/crescimento & desenvolvimento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA