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1.
Light Res Technol ; 55(4-5): 474-486, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37469656

RESUMO

This article describes the development of a device to investigate the non-visual responses to light: The Light-Dosimeter (lido). Its multidisciplinary team followed a user-centred approach throughout the project, that is, their design decisions focused on researchers' and participants' needs. Together with custom-made mountings and the software Lido Studio, the lidos provide researchers with a holistic solution to record participants' light exposure in the near-corneal plane in laboratory settings and under real-world conditions. Validation measurements with commercial equipment were deemed satisfying, as was the combining with data from other devices. The handling of the lidos and mountings and the use of the software Lido Studio during the trial period by various researchers and participants were successful. Despite some limitations, the lidos can help advance research on the non-visual responses to light over the coming years.

2.
Infection ; 48(1): 51-56, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31203513

RESUMO

BACKGROUND: Seasonal influenza outbreaks are associated with increased mortality and hospitalisation rates. Herein we tried to identify predictors of mortality in hospitalised patients with influenza virus infection. MATERIALS/METHODS: In this exploratory retrospective observational single-centre-study we included all influenza-positive patients older than 18 years who were hospitalised and treated at the flu-isolation-ward during the influenza season 2017/18. Diagnosis was based on point-of-care-test with the Alere™ i. First we performed χ2 tests and Mann-Whitney U tests to identify predictors of mortality. Significant variables were used in a stepwise-forward-logistic-regression-model to predict in-hospital and 90-day mortality. RESULTS: Of the 396 patients who tested positive for influenza 96 (24.2%) had influenza A and 300 (75.8%) influenza B. Twenty-two (5.6%) died in hospital and the 90-day mortality rate was 9.4%. In the stepwise logistic regression older age (OR 1.1 per year 95% CI 1.03-1.17), history of atrial fibrillation (OR 5.91 95% CI 1.91-18.34), dementia (OR 3.98 95% CI 1.24-12.78), leucocyte count (OR 1.11 per G/L 95% CI 1.03-1.20), pneumonia (OR 4.39 95% CI 1.44-13.39) and acute heart failure (OR 23.15 95% CI 4.33-123.76) increased the risk of in-hospital mortality. The risk for 90-day mortality was increased by older age (OR 1.04 per year 95% CI 1.01-1.07), history of atrial fibrillation (OR 3.1, 95% CI 1.36-7.05), history of congestive heart failure (OR 4.7 95% CI 1.94-11.48), pneumonia (OR 3.2 95% CI 1.45-6.91) and decreased by statin use (OR 0.28 95% CI 0.10-0.78). CONCLUSIONS: Older age, history of atrial fibrillation and pneumonia are associated with increased risk of influenza-associated in-hospital and 90-day mortality. Statin use may decrease 90-day mortality.


Assuntos
Mortalidade Hospitalar , Influenza Humana/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Áustria/epidemiologia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Orthomyxoviridae/fisiologia , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Adulto Jovem
3.
Herz ; 43(3): 197-206, 2018 May.
Artigo em Alemão | MEDLINE | ID: mdl-29188356

RESUMO

Arterial hypertension is the most common modifiable risk factor for cerebrovascular and cardiovascular morbidity and mortality in old age. The prevention of cognitive brain disorders is also a therapeutic goal of long-term treatment of hypertension. Older patients also have a higher risk of developing cardiovascular diseases and therefore benefit from a relatively moderate reduction in blood pressure. With respect to the high prevalence of hypertension in old age and the increasing incidence with time, the therapy of hypertension is becoming increasingly more important to achieve an improved prognosis for patients along with a reduction of costs. The accurate blood pressure measurement for elderly patients includes repeated measurements while standing and sitting. Additionally, the measurements should also be conducted by the patient or by a family member. The most accurate method for assessing the daily blood pressure level, e.g. practice hypertension, non-dipping and intermittent hypertension, is the 24-h blood pressure measurement by ambulatory blood pressure monitoring (ABPM). General measures and lifestyle interventions are effective for reducing blood pressure of elderly patients with hypertension and a low salt diet is scientifically proven to be superior. The same drugs used for young people are also recommended for older patients and most give preference to diuretics, renin-angiotensin-aldosterone system (RAAS) inhibitors and calcium antagonists. The target blood pressure in elderly patients is repeatedly the focus of scientific discussions. The current recommendations are presented in the text and the characteristics which must be particularly considered in the therapy of elderly patients are presented in detail.


Assuntos
Anti-Hipertensivos , Monitorização Ambulatorial da Pressão Arterial , Hipertensão , Idoso , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Determinação da Pressão Arterial , Humanos , Hipertensão/tratamento farmacológico
4.
Pharmacogenomics J ; 14(3): 272-80, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23979174

RESUMO

Despite the clinical benefit of statin therapy and the numerous strategies used to improve adherence, no strategy has used direct communication of genetic test results to the patient as an adherence and persistence motivator. We investigated in a real-world setting the effect of a process of providing KIF6 test results and risk information directly to 647 tested patients on 6-month statin adherence (proportion of days covered (PDC)) and persistence compared with concurrent non-tested matched controls. Adjusted 6-month statin PDC was significantly greater in tested patients: 0.77 (95% confidence interval (CI) 0.72-0.82) vs controls 0.68 (95% CI 0.63-0.73), P<0.0001. Significantly more tested patients were adherent (PDC⩾0.80) (63.4% (59.6-67.1%) vs 45.0% (41.1-48.8%), P<0.0001) and persisted on therapy (69.1% (65.4-72.5%) vs 53.3% (49.4-57.1%), P<0.0001). Similar results were observed in a secondary comparison with 779 unmatched patients who declined testing. The Additional KIF6 Risk Offers Better Adherence to Statins trial provides the first evidence that pharmacogenetic testing may modify patient adherence.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Cooperação do Paciente , Farmacogenética , Idoso , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Masculino , Pessoa de Meia-Idade
5.
J Am Coll Cardiol ; 19(5): 1060-4, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1552096

RESUMO

The hemodynamic effects of intravenously administered adenosine, a potent vasodilator, were examined in 15 patients with pulmonary hypertension. All patients were given adenosine, 50 micrograms/kg per min, increased by 50 micrograms/kg per min at 2 min intervals to a maximum of 500 micrograms/kg per min or until the development of untoward side effects. The patients were then given oral nifedipine, 20 mg every hour, until a greater than or equal to 20% decrease in pulmonary vascular resistance or systemic hypotension occurred. The administration of maximal doses of adenosine, 256 +/- 46 micrograms/kg per min, produced a 2.4% reduction in pulmonary artery pressure (p = NS), a 37% decrease in pulmonary vascular resistance (p less than 0.001) and a 57% increase in cardiac index (p less than 0.001). The administration of maximally effective doses of nifedipine (91 +/- 36 mg) produced a 15% reduction in the mean pulmonary artery pressure (p less than 0.05), a 24% decrease in pulmonary vascular resistance (p less than 0.01) and an 8% increase in cardiac index (p = NS). There was a significant correlation (r = 0.714, p = 0.01) between the reduction in pulmonary vascular resistance that resulted from adenosine administration and that achieved with the administration of nifedipine. Six patients had substantial reductions in pulmonary vascular resistance with adenosine but not with nifedipine. Thus, adenosine is an effective vasodilator in patients with pulmonary hypertension and can be used for safe and rapid assessment of vasodilator reserve in these patients.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Adenosina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Hipertensão Pulmonar/diagnóstico , Nifedipino/farmacologia , Resistência Vascular/efeitos dos fármacos , Adenosina/administração & dosagem , Adulto , Relação Dose-Resposta a Droga , Feminino , Humanos , Hipertensão Pulmonar/fisiopatologia , Masculino , Nifedipino/administração & dosagem , Vasodilatação/efeitos dos fármacos
6.
J Am Coll Cardiol ; 21(2): 413-8, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8426006

RESUMO

OBJECTIVES: The purpose of this study was to evaluate the effects of vasodilator combination therapy in patients with primary pulmonary hypertension. BACKGROUND: Calcium channel blockers and adenosine have each been shown to be effective in reducing pulmonary artery pressure and pulmonary vascular resistance in patients with primary pulmonary hypertension. However, the effects of combining these vasodilators have not been studied. METHODS: To test the combination, 12 patients were placed on oral nifedipine and 3 on diltiazem therapy, using a dose titrated to maximal effect (mean nifedipine dose 103 +/- 24 mg, mean diltiazem dose 300 +/- 49 mg). Patients were then given maintenance doses of the calcium channel blocker at half the cumulative loading dose at 6-h intervals. One hour after the maintenance dose of calcium blocker, all patients received an infusion of adenosine, starting with 50 micrograms/kg per min and increasing by 50 micrograms/kg per min at 2-min intervals to a maximally tolerated dose (180 +/- 63 micrograms/kg per min). RESULTS: Ten patients responded to calcium channel blockers (defined as a > or = 20% decrease in pulmonary vascular resistance), with a 16% decrease in mean pulmonary artery pressure (p = 0.057), a 39% decrease in pulmonary vascular resistance (p = 0.002) and a 24% increase in stroke volume (p = 0.007). Five patients were nonresponders, with no significant changes in pulmonary artery pressure, pulmonary vascular resistance, cardiac index or stroke volume. In the calcium channel blocker responders, the combination of adenosine and calcium blocker reduced pulmonary vascular resistance by 49%, increased stroke volume by 33% and decreased mean pulmonary artery pressure by 14% compared with drug-free baseline values. In nonresponders, combination therapy resulted in nonsignificant changes in pulmonary artery pressure and pulmonary vascular resistance. CONCLUSIONS: Adenosine has the ability to further decrease pulmonary artery pressure and pulmonary vascular resistance in patients with primary pulmonary hypertension who respond to calcium channel blockers. Those who fail to respond to these agents have little added effect from adenosine.


Assuntos
Adenosina/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Hipertensão Pulmonar/tratamento farmacológico , Circulação Pulmonar/efeitos dos fármacos , Adenosina/administração & dosagem , Adulto , Bloqueadores dos Canais de Cálcio/administração & dosagem , Cateterismo de Swan-Ganz , Diltiazem/administração & dosagem , Diltiazem/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Masculino , Nifedipino/administração & dosagem , Nifedipino/uso terapêutico , Volume Sistólico/efeitos dos fármacos , Termodiluição , Resistência Vascular/efeitos dos fármacos
7.
Acta Neurochir Suppl ; 93: 105-11, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15986738

RESUMO

Deep brain stimulation has gained increasing interest in the treatment of movement disorders. Presenting our clinical series of 179 patients operated upon since 1999, the indications, risks and benefits for the patients are discussed in order to further improve the techniques and their applications.


Assuntos
Estimulação Encefálica Profunda/métodos , Transtornos dos Movimentos/etiologia , Transtornos dos Movimentos/reabilitação , Doença de Parkinson/complicações , Doença de Parkinson/reabilitação , Medição de Risco/métodos , Estimulação Encefálica Profunda/efeitos adversos , Humanos , Prognóstico , Fatores de Risco , Resultado do Tratamento
8.
Neurology ; 57(1): 144-6, 2001 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-11445647

RESUMO

Gait analysis was carried out to assess the effects of L-dopa and bilateral subthalamic nucleus stimulation on gait velocity, cadence, stride length, and gait kinematics in nine patients with PD. Substantial effects of bilateral subthalamic nucleus stimulation on gait, with an increase in gait velocity and stride length comparable to that of a suprathreshold L-dopa dose, were found. Interestingly, stride length was more improved by L-dopa and cadence more by subthalamic nucleus stimulation. In two patients with freezing during the "on" period, subthalamic nucleus stimulation failed to reduce this symptom effectively.


Assuntos
Terapia por Estimulação Elétrica , Marcha , Doença de Parkinson/fisiopatologia , Doença de Parkinson/terapia , Núcleo Subtalâmico/fisiopatologia , Antiparkinsonianos/uso terapêutico , Fenômenos Biomecânicos , Humanos , Levodopa/uso terapêutico , Pessoa de Meia-Idade , Fatores de Tempo
9.
Am J Cardiol ; 77(11): 996-9, 1996 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-8644652

RESUMO

In patients with primary pulmonary hypertension who respond to nifedipine during acute drug testing, there is a significant linear correlation of serum nifedipine concentration with pulmonary artery pressure and resistance. Although most demonstrate an initial response at readily attainable nifedipine concentrations with conventional dosages, a subset of patients seem to display delayed or incomplete oral absorption; these results may facilitate the clinical use of nifedipine in patients with primary pulmonary hypertension.


Assuntos
Hipertensão Pulmonar/tratamento farmacológico , Nifedipino/administração & dosagem , Nifedipino/sangue , Vasodilatadores/administração & dosagem , Vasodilatadores/sangue , Adulto , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Hipertensão Pulmonar/fisiopatologia , Masculino , Pessoa de Meia-Idade
10.
Chest ; 107(1): 54-7, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7813311

RESUMO

Vasodilators have been a main focus of therapy for primary pulmonary hypertension. Adenosine and prostacyclin have been shown to reduce pulmonary vascular resistance acutely in these patients. In order to compare the acute hemodynamic effects of adenosine and prostacyclin, ten patients with severe primary pulmonary hypertension, unresponsive to medical therapy, were studied. After baseline hemodynamics were obtained, an adenosine infusion, 50 to 100 ng/kg/min, was begun and titrated to the maximum tolerated dose. Hemodynamics were allowed to return to baseline, and thereafter, a prostacyclin infusion was begun at 2 ng/kg/min, and titrated to the maximum tolerated dose. Overall, adenosine (200 +/- 53 ng/kg/min) produced a 33 +/- 18% (p < 0.001) fall in pulmonary vascular resistance and a 52 +/- 25% (p < 0.001) increase in cardiac output with no effect on pulmonary or systemic arterial pressures. Prostacyclin (8 +/- 4 ng/kg/min) caused a 22 +/- 18% (p < 0.01) fall in pulmonary vascular resistance and a 25 +/- 26% (p < 0.05) increase in cardiac output with a 14 +/- 6% (p < 0.001) decrease in systemic arterial pressure, but no change in pulmonary arterial pressure. The effects of adenosine and prostacyclin on pulmonary vascular resistance were similar (r = 0.70, r2 = 0.49, p = 0.02). Adenosine and prostacyclin have similar hemodynamic effects acutely in primary pulmonary hypertension. Adenosine may be useful as a test of the potential for long-term prostacyclin therapy in patients with primary pulmonary hypertension.


Assuntos
Adenosina/farmacologia , Epoprostenol/farmacologia , Hemodinâmica/efeitos dos fármacos , Hipertensão Pulmonar/fisiopatologia , Adulto , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Circulação Pulmonar/efeitos dos fármacos , Resistência Vascular/efeitos dos fármacos
11.
J Clin Pharmacol ; 31(12): 1126-31, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1662232

RESUMO

Digoxin-like immunoreactive substance (DLIS) has been detected in several patient populations that were not receiving digoxin, including those patients with end-stage renal disease. The structure and physiologic significance of this compound are unknown, and the fate of DLIS after renal transplantation has not been studied. The authors prospectively evaluated 163 patients (not receiving digoxin) before and after transplantation for the presence of DLIS. Three different assays were used: radioimmunoassay (RIA), affinity mediated immunoassay (ACA), and fluorescence polarization immunoassay (TDX I). Depending on the assay method used, 11% (RIA), 6% (ACA), and 9% (TDX) of patients had detectable DLIS pretransplant. Using all 3 assays, a total of 34 patients (21%) were found to have DLIS. The mean serum digoxin concentration was 0.41 +/- 0.13 ng/mL (range: 0.2-1.2 ng/mL) and DLIS was detectable by greater than 1 assay method in seven patients. DLIS persisted longer in patients who had delayed allograft function (13.7 +/- 7 days) than in those who did not (3 +/- 1.9 days), P less than .05. In summary, detection of DLIS in renal transplant recipients appears to be an infrequent occurrence when using a single digoxin assay method. When detected, the concentration of DLIS is often below the usual therapeutic range for digoxin and disappears once allograft function is established. The authors conclude that the presence of DLIS is unlikely to be clinically significant in the renal transplant population.


Assuntos
Proteínas Sanguíneas/análise , Digoxina , Transplante de Rim , Saponinas , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Adulto , Cardenolídeos , Feminino , Humanos , Falência Renal Crônica/metabolismo , Falência Renal Crônica/cirurgia , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
12.
J Neurol ; 247 Suppl 2: II122-34, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10991659

RESUMO

Levodopa is a highly effective treatment of all motor symptoms of Parkinson's disease. However, long-term treatment with levodopa can lead to motor fluctuations and levodopa-induced dyskinesias. Motor side effects can become so disabling as to warrant surgical treatment. Both ablative surgery and deep brain stimulation (DBS) for Parkinson's disease (PD) can be performed in different target areas. Thalamic surgery mainly improves tremor, and to a lesser extent also rigidity and dyskinesias, whereas pallidal and subthalamic nucleus surgery improves all motor symptoms and levodopa-induced dyskinesias. The efficacy and safety of unilateral pallidotomy is well established. DBS has a lower morbidity and is safe enough to be performed bilaterally. The subthalamic nucleus (STN) presently seems to be the most promising target for DBS in advanced stage PD.


Assuntos
Globo Pálido/cirurgia , Doença de Parkinson/cirurgia , Núcleo Subtalâmico/cirurgia , Tálamo/cirurgia , Globo Pálido/fisiopatologia , Humanos , Doença de Parkinson/fisiopatologia , Complicações Pós-Operatórias , Núcleo Subtalâmico/fisiopatologia , Tálamo/fisiopatologia
13.
Pharmacotherapy ; 6(2): 83-6, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3086849

RESUMO

The acceptance, preference, and side effects of the 3 commercially available nitroglycerin patches were examined in 30 patients with chronic, stable angina pectoris. Patients were serially interviewed after each treatment period regarding patch comfort, aesthetics, discomfort upon removal, adhesiveness, efficacy, and side effects. They were also interviewed and examined for adverse skin reactions. There were significant differences among the 3 patches with respect to comfort, aesthetics, discomfort, and adhesiveness. Skin reactions (mostly mild) occurred in 83% of patients: patch A, 70%; patch B, 43%; and patch C, 57%. Intolerable reactions, which would have caused patch discontinuation, were noted in 40% of patients: patch A, 30%; patch B, 7%; and patch C, 10%. Most patients had an intolerable reaction to only 1 patch. Significant differences were present only between patches A and B with respect to total and intolerable skin reactions. Thus the systems differed in terms of patient preference and skin reactions. Skin reactions are probably more prevalent than previously reported but usually occur with just one of the patches. Physicians and hospitals should probably individualize nitrate patch therapy within formulary and budgetary constraints.


Assuntos
Angina Pectoris/tratamento farmacológico , Dermatite de Contato/etiologia , Nitroglicerina/administração & dosagem , Adesividade , Administração Tópica , Adulto , Idoso , Doença Crônica , Preparações de Ação Retardada , Dermatite de Contato/fisiopatologia , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Nitroglicerina/efeitos adversos , Aceitação pelo Paciente de Cuidados de Saúde , Distribuição Aleatória
14.
Anal Bioanal Chem ; 355(3-4): 233-9, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15045370

RESUMO

Raman spectroscopy has enjoyed a dramatic improvement during the last years: The interference by the fluorescence of impurities is virtually eliminated, the sample preparation is considerably easier as for infrared spectroscopy and many applications in routine analytics, quality control and process control in various branches of industry are now possible. It is shown that the up-to-date near-infrared Raman spectrometers now meet most demands for a modern analytical instrument concerning applicability, analytical information and convenience. It can be anticipated that Raman spectroscopy will catch up infrared spectroscopy, the current workhorse of vibrational spectroscopy.

15.
J Agric Food Chem ; 51(9): 2475-81, 2003 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-12696923

RESUMO

The potential of vibrational spectroscopy methods (attenuated total reflectance/Fourier-transform-infrared (ATR/FT-IR), FT-Raman and near infrared (NIR) spectroscopy) for the identification and quantification of valuable as well as carcinogenic substances in different basil chemotypes is described. It is shown that all main volatile components occurring in different basil accessions can be reliably determined in the isolated essential oils or solvent extracts but also in the air-dried herbs. While NIR data can be interpreted only by chemometric methods, IR and Raman spectra present characteristic key bands of the individual volatiles; therefore, in the latter case, a discrimination of basil chemotypes is frequently possible without applying chemometric algorithms. NIR calibrations are successfully established for various terpenoids and phenylpropanoids; on the basis of these data, the content of the two carcinogenic compounds methyleugenol (range: 2-235 microg/100 g) and estragole (range: 34-138 microg/100 g) can be reliably predicted in air-dried basil leaves (R (2) (coefficient of determination) = 0.951; SECV (standard error of cross validation) = 19.1 microg/100 g and R (2) = 0.890; SECV = 12.8 microg/100 g, respectively). The described methods were found to be very useful tools for the efficient selection of special basil single plants, adapted to the new demands set by the legislator and the consumer. Furthermore, they can be applied in industry to very easily control the purifying, blending, and redistilling processes of basil oil.


Assuntos
Carcinógenos/análise , Ocimum basilicum/química , Óleos Voláteis/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Análise Espectral Raman/métodos , Calibragem , Ocimum basilicum/classificação
16.
J Pharm Biomed Anal ; 15(9-10): 1319-24, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9226559

RESUMO

The constitutional isomers of biliverdin dimethyl ester, IX alpha and XIII alpha, were studied by resonance Raman spectroscopy. The far-reaching spectral similarities suggest that despite the different substitution patterns, the compositions of the normal modes are closely related. This conclusion does not hold only for the parent state (ZZZ, sss configuration) but also for the configurational isomers which were obtained upon double-bond photoisomerization. Based on a comparison of the resonance Raman spectra, a EZZ configuration is proposed for one of the two photoisomers of biliverdin dimethyl ester IX alpha, while a ZZE, ssa configuration has been assigned previously to the second isomer.


Assuntos
Biliverdina/análogos & derivados , Análise Espectral Raman , Biliverdina/análise , Estrutura Molecular , Fotoquímica , Estereoisomerismo , Vibração
17.
Health Phys ; 81(2 Suppl): S33-5, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11480863

RESUMO

Radioactively contaminated laundry is normally sent off site for processing. Laundry is defined as radiologically contaminated anti-cs and respirators. This laundry is shipped as "limited quantity," in accordance with 49CFR173.421. This requires that 95% of the radionuclides shipped are characterized and quantified. In addition, the total quantity must be 10(-3) below the A2 limits specified in 49CFR173. In any facility evaluated, the most conservative (highest activity) waste stream was used as the source term. If a new waste stream is established for a facility, its normalized activity should be compared to the evaluated waste stream to ensure the limits are not exceeded. This article documents a method used for estimating the radionuclide content in contaminated laundry. The maximum values were compared to 49CFR173. Itwas determined that if the contaminated laundry/respirators are shipped in an Interstate Nuclear Services (INS), L-59, limited quantity shipping container and the highest contact radiation level on any side, as measured with an ion chamber, does not exceed 0.5 mR h(-1), the container complies with the requirements of 49CFR173 and could be shipped "limited quantity" from any of the facilities evaluated.


Assuntos
Lavanderia , Resíduos Radioativos , Radioisótopos , Humanos
18.
Biomed Instrum Technol ; 33(4): 373-82, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10459425

RESUMO

Partial Liquid Ventilation (PLV), a treatment for acute respiratory failure in which the lungs are filled, either partially or to functional residual capacity (FRC), with perfluorochemical (PFC) liquid while the patient is on mechanical gas ventilation, has progressed to clinical trials using the PFC perflubron (PFB). Because gas expired during PLV is laden with PFB vapor, PFB is lost via evaporation, which increases dose consumption and necessitates periodic redosing. A device has been developed to minimize evaporative loss by confining PFC vapor to a gas volume breathed by the patient, which is isolated from the ventilator. This closed rebreathing system works with the ventilator such that after the lung is filled with PFB, the patient is connected to the rebreathing system, with breathing still "driven" by the ventilator. The rebreathing system consists of two gas circuits, or compartments, separated by a flexible bag (in a box) partition. One compartment is in gas communication with the lung, while the second communicates with the ventilator. The O2 level on the patient side is matched to that on the ventilator side by sensing gas concentrations and by feedback control of O2 introduction. Similarly, air is introduced into the patient side under pressure-based feedback control to maintain a constant gas volume. On inspiration, the ventilator delivers the tidal volume (breath) into the box surrounding the bag, which, in turn, is transmitted through the bag to the lung. On expiration, the process is reversed. Unidirectional circulation of gas in the rebreathing circuit is achieved via check valves, and expired CO2 is removed by a barium hydroxide lime cartridge. Airway humidification is maintained by captive water vapor in the system and water vapor from the CO2 absorber. It is recommended that flow, pressure, O2, and CO2 levels be monitored at the patient "Y," i.e., the proximal end of the endotracheal tube. Performance data from both in-vitro experiments and in-vivo PLV experiments in pigs are presented. The authors conclude that with the closed rebreathing system, the dose can be safely maintained with fewer redosing procedures, and an approximately 90% savings in dose is achieved.


Assuntos
Emulsões/administração & dosagem , Fluorocarbonos/administração & dosagem , Troca Gasosa Pulmonar/fisiologia , Ventiladores Mecânicos , Animais , Calibragem , Desenho de Equipamento , Feminino , Humanos , Hidrocarbonetos Bromados , Técnicas In Vitro , Masculino , Modelos Biológicos , Oxigênio/fisiologia , Pressão , Suínos , Volume de Ventilação Pulmonar
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