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Endothelial dysfunction, one of many causes of arterial changes in end-stage kidney disease (kidney failure), is a likely link between early vascular aging and the risk of thrombosis or bleeding in this condition. To evaluate this, we compared links between arterial stiffness and endothelial/coagulation factors in 55 patients receiving hemodialysis therapy and 57 age-/sex-matched control individuals. Arterial stiffness was assessed from carotid-femoral pulse wave velocity, and coagulation status from the endogenous thrombin generating potential. Markers of endothelial dysfunction (von Willebrand factor, tissue factor pathway inhibitor), neutrophil extracellular traps and tissue factor-positive extracellular vesicles were higher in patients with kidney failure. Prothrombin fragments 1 and 2, and D-dimer markers of in vivo coagulation activation were also higher. However, in vitro in the presence of platelets, endogenous thrombin generating potential was lower and its downregulation by activated protein C impaired. Antiplatelet drugs did not affect these parameters. In multiple regression analysis, prothrombin fragments 1 and 2, D-dimer, factor VIII and monocyte-derived tissue factor-positive extracellular vesicles correlated with higher carotid-femoral pulse wave velocity. In patients with kidney failure, in vivo hypercoagulability occurred with reduced thrombin generation in platelet-rich plasma, likely explaining the opposing thrombotic and bleeding tendencies in patients with kidney failure. Importantly, arteriosclerosis is more closely related to a prothrombotic state. Thus, coagulation changes plus arterial stiffness highlight a major therapeutic challenge for anticoagulant and antiplatelet drug use.
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Arteriosclerose , Insuficiência Renal , Coagulação Sanguínea , Estudos de Casos e Controles , Humanos , Análise de Onda de Pulso , Insuficiência Renal/etiologia , TrombinaRESUMO
BACKGROUND: The use of a 'do not interrupt' vest during medication administration rounds is recommended but there have been no controlled randomized studies to evaluate its impact on reducing administration errors. We aimed to evaluate the impact of wearing such a vest on reducing such errors. The secondary objectives were to evaluate the types and potential clinical impact of errors, the association between errors and several risk factors (such as interruptions), and nurses' experiences. METHODS: This was a multicenter, cluster, controlled, randomized study (March-July 2017) in 29 adult units (4 hospitals). Data were collected by direct observation by trained observers. All nurses from selected units were informed. A 'Do not interrupt' vest was implemented in all units of the experimental group. A poster was placed at the entrance of these units to inform patients and relatives. The main outcome was the administration error rate (number of Opportunities for Error (OE), calculated as one or more errors divided by the Total Opportunities for Error (TOE) and multiplied by 100). RESULTS: We enrolled 178 nurses and 1346 patients during 383 medication rounds in 14 units in the experimental group and 15 units in the control group. During the intervention period, the administration error rates were 7.09% (188 OE with at least one error/2653 TOE) for the experimental group and 6.23% (210 OE with at least one error/3373 TOE) for the control group (p = 0.192). Identified risk factors (patient age, nurses' experience, nurses' workload, unit exposition, and interruption) were not associated with the error rate. The main error type observed for both groups was wrong dosage-form. Most errors had no clinical impact for the patient and the interruption rates were 15.04% for the experimental group and 20.75% for the control group. CONCLUSIONS: The intervention vest had no impact on medication administration error or interruption rates. Further studies need to be performed taking into consideration the limitations of our study and other risk factors associated with other interventions, such as nurse's training and/or a barcode system. TRIAL REGISTRATION: The PERMIS study protocol (V2-1, 11/04/2017) was approved by institutional review boards and ethics committees (CPP Ile de France number 2016-A00211-50, CNIL 21/03/2017, CCTIRS 11/04/2016). It is registered at ClinicalTrials.gov (registration number: NCT03062852 , date of first registration: 23/02/2017).
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OBJECTIVE: To compare the costs and benefits of an automated-drug dispensing cabinet (ADC) versus traditional floor stock storage (TFSS). DESIGN: A quasi-experimental multicenter study conducted during 2015. SETTING: A teaching hospital (814 beds) equipped with 43 ADCs and a not-for-profit teaching hospital (643 beds) equipped with 38 TFSS systems, in Paris, France. PARTICIPANTS: All the wards of the two hospitals were included in the study. INTERVENTION(S): ADC versus TFSS. MAIN OUTCOME MEASURE(S): A composite outcome composed of cost and benefits. RESULTS: The total cost with payback period was substantially higher for the ADCs (574 006 for 41 ADCs) than TFSS (190 305 for 30 TFSS systems). The mean number of costly drugs and units were significantly higher for ADCs (P < 0.001). There was no significant difference in the mean number of overall drugs and units. There were significantly fewer urgent global deliveries with ADCs than TFSS units. Nurses' satisfaction with ADCs was high and the prevalence of medication process errors related to ADCs was low. No event due to storage errors was reported for ADCs and nine events were reported for TFSS units. On the contrary, informatic-related events increased with the use of ADCs, as expected. CONCLUSIONS: Overall, ADCs are well-established in wards and are particularly appreciated by nurses. A significant difference in the initial investment cost was confirmed, but it must be adjusted over time. This difference is offset in the long-term by gains in preparation time and fewer medication process errors, securing the medication process.
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Armazenamento de Medicamentos/economia , Erros de Medicação/estatística & dados numéricos , Sistemas de Medicação no Hospital/economia , Serviço de Farmácia Hospitalar/economia , França , Hospitais de Ensino , Humanos , Erros de Medicação/economia , Recursos Humanos de Enfermagem Hospitalar/psicologia , Robótica/instrumentaçãoRESUMO
Central artery stiffening is recognized as a cardiovascular risk. The effects of hypertension and aging have been shown in human and animal models but the effect of salt is still controversial. We studied the effect of a high-salt diet on aortic stiffness in salt-sensitive spontaneously hypersensitive stroke-prone rats (SHRSP). Distensibility, distension, and ß-stiffness were measured at thoracic and abdominal aortic sites in the same rats, using echotracking recording of the aortic diameter coupled with blood pressure (BP), in SHRSP-salt (5% salted diet, 5 weeks), SHRSP, and normotensive Wistar-Kyoto (WKY) rats. Hemodynamic parameters were measured at BP matched to that of WKY. Histological staining and immunohistochemistry were used for structural analysis. Hemodynamic isobaric parameters in SHRSP did not differ from WKY and only those from the abdominal aorta of SHRSP-salt presented decreased distensibility and increased stiffness compared with WKY and SHRSP. The abdominal and thoracic aortas presented similar thickening, increased fibrosis, and remodeling with no change in collagen content. SHRSP-salt presented a specific increased elastin disarray at the abdominal aorta level but a decrease in elastin content in the thoracic aorta. This study demonstrates the pro-stiffening effect of salt in addition to hypertension; it shows that only the abdominal aorta presents a specific pressure-independent stiffening, in which elastin disarray is likely a key mechanism.
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Aorta Abdominal/fisiopatologia , Aorta Torácica/fisiopatologia , Pressão Arterial , Hipertensão/fisiopatologia , Cloreto de Sódio na Dieta , Rigidez Vascular , Animais , Aorta Abdominal/metabolismo , Aorta Abdominal/patologia , Aorta Torácica/metabolismo , Aorta Torácica/patologia , Modelos Animais de Doenças , Elastina/metabolismo , Fibrose , Hipertensão/etiologia , Hipertensão/metabolismo , Hipertensão/patologia , Masculino , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Remodelação VascularRESUMO
Background Medication review is time-consuming and not exhaustive in most French hospitals. We routinely use an innovative hybrid decision support system using Artificial Intelligence to prioritize medication review by scoring prescriptions by their risk of containing at least one drug related problem (DRP). Aim Our aim was to attest that the prescriptions with low risk of DRPs ruled out by the tool in everyday practice were effectively free of any DRPs with potentially severe clinical impact. Methods We conducted a randomized single-blinded study to compare the rate of pharmaceutical interventions (PI) between low and high-risk prescriptions defined by the tool's calculated score. Prescriptions were reviewed daily by a clinical pharmacist. Proportion of prescriptions with at least one severe DRP was calculated in both groups. Severe DRPs were characterized through a multidisciplinary approach. Results Four hundred and twenty (107 low score and 313 high score) prescriptions were analyzed. The percentage of prescriptions with severe DRPs was dramatically decreased in low score prescriptions (2.8% vs. 15.3% for high-risk; p = 0.0248). A significant difference was found (94% vs. 20%; p < 0.001) in the percentage of severe DRPs detected by the hybrid approach compared to a CDSS. During the study period, the hybrid tool allowed to rule out 55% of all prescriptions in our hospital.Conclusion This hybrid decision support tool has shown to be accurate to detect DRPs in daily practice. Despite some limitations, it offers the best possible solution to prioritized medication review, considering the shortage of clinical pharmacists in France and considerably improves the safety of patients' care.
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Inteligência Artificial , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Aprendizado de Máquina , Revisão de Medicamentos , Farmacêuticos , PrescriçõesRESUMO
OBJECTIVE: To improve patient safety and clinical outcomes by reducing the risk of prescribing errors, we tested the accuracy of a hybrid clinical decision support system in prioritizing prescription checks. MATERIALS AND METHODS: Data from electronic health records were collated over a period of 18 months. Inferred scores at a patient level (probability of a patient's set of active orders to require a pharmacist review) were calculated using a hybrid approach (machine learning and a rule-based expert system). A clinical pharmacist analyzed randomly selected prescription orders over a 2-week period to corroborate our findings. Predicted scores were compared with the pharmacist's review using the area under the receiving-operating characteristic curve and area under the precision-recall curve. These metrics were compared with existing tools: computerized alerts generated by a clinical decision support (CDS) system and a literature-based multicriteria query prioritization technique. Data from 10 716 individual patients (133 179 prescription orders) were used to train the algorithm on the basis of 25 features in a development dataset. RESULTS: While the pharmacist analyzed 412 individual patients (3364 prescription orders) in an independent validation dataset, the areas under the receiving-operating characteristic and precision-recall curves of our digital system were 0.81 and 0.75, respectively, thus demonstrating greater accuracy than the CDS system (0.65 and 0.56, respectively) and multicriteria query techniques (0.68 and 0.56, respectively). DISCUSSION: Our innovative digital tool was notably more accurate than existing techniques (CDS system and multicriteria query) at intercepting potential prescription errors. CONCLUSIONS: By primarily targeting high-risk patients, this novel hybrid decision support system improved the accuracy and reliability of prescription checks in a hospital setting.
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Sistemas de Apoio a Decisões Clínicas , Aprendizado de Máquina , Sistemas de Registro de Ordens Médicas , Erros de Medicação/prevenção & controle , Sistemas Inteligentes , Hospitais Filantrópicos , Humanos , Paris , Segurança do Paciente , Farmacêuticos , Prescrições , Curva ROCRESUMO
BACKGROUND: Coronaviruses can induce the production of interleukin (IL)-1ß, IL-6, tumour necrosis factor, and other cytokines implicated in autoinflammatory disorders. It has been postulated that anakinra, a recombinant IL-1 receptor antagonist, might help to neutralise the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-related hyperinflammatory state, which is considered to be one cause of acute respiratory distress among patients with COVID-19. We aimed to assess the off-label use of anakinra in patients who were admitted to hospital for severe forms of COVID-19 with symptoms indicative of worsening respiratory function. METHODS: The Ana-COVID study included a prospective cohort from Groupe Hospitalier Paris Saint-Joseph (Paris, France) and a historical control cohort retrospectively selected from the Groupe Hospitalier Paris Saint-Joseph COVID cohort, which began on March 18, 2020. Patients were included in the prospective cohort if they were aged 18 years or older and admitted to Groupe Hospitalier Paris Saint-Joseph with severe COVID-19-related bilateral pneumonia on chest x-ray or lung CT scan. The other inclusion criteria were either laboratory-confirmed SARS-CoV-2 or typical lung infiltrates on a lung CT scan, and either an oxygen saturation of 93% or less under oxygen 6 L/min or more, or aggravation (saturation ≤93% under oxygen 3 L/min) with a loss of 3% of oxygen saturation in ambient air over the previous 24 h. The historical control group of patients had the same inclusion criteria. Patients in the anakinra group were treated with subcutaneous anakinra (100 mg twice a day for 72 h, then 100 mg daily for 7 days) as well as the standard treatments at the institution at the time. Patients in the historical group received standard treatments and supportive care. The main outcome was a composite of either admission to the intensive care unit (ICU) for invasive mechanical ventilation or death. The main analysis was done on an intention-to-treat basis (including all patients in the anakinra group who received at least one injection of anakinra). FINDINGS: From March 24 to April 6, 2020, 52 consecutive patients were included in the anakinra group and 44 historical patients were identified in the Groupe Hospitalier Paris Saint-Joseph COVID cohort study. Admission to the ICU for invasive mechanical ventilation or death occurred in 13 (25%) patients in the anakinra group and 32 (73%) patients in the historical group (hazard ratio [HR] 0·22 [95% CI 0·11-0·41; p<0·0001). The treatment effect of anakinra remained significant in the multivariate analysis (HR 0·22 [95% CI 0·10-0·49]; p=0·0002). An increase in liver aminotransferases occurred in seven (13%) patients in the anakinra group and four (9%) patients in the historical group. INTERPRETATION: Anakinra reduced both need for invasive mechanical ventilation in the ICU and mortality among patients with severe forms of COVID-19, without serious side-effects. Confirmation of efficacy will require controlled trials. FUNDING: Groupe Hospitalier Paris Saint-Joseph.
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The spontaneously hypertensive rat model with reduced NO synthesis (SHRLN) shares features with aging and hypertension in humans, among other a severe aortic stiffening. The present in vivo study aimed to compare thoracic (TA) and abdominal (AA) aortic stiffness in the SHRLN (treated 5 weeks with L-NAME), SHR, and normotensive Wistar Kyoto (WKY). Dynamic properties of TA and AA were measured in the same rats, using echotracking recording of aortic diameter coupled with blood pressure (BP). Measurements were performed first at operating BP and then after BP reduction in hypertensive rats, thus in isobaric conditions. Histological staining and immunohistochemistry were used for structural analysis at both sites. At operating pressure, BP and pulse pressure (PP) were higher in SHRLN compared with SHR. Stiffness index was also increased and distensibility decreased in both TA and AA in SHRLN. At WKY-matched blood pressure, isobaric AA parameters remained specifically altered in SHRLN, whereas TA recovered to values identical to WKYs. Collagen, fibronectin, α5-selectin, and FAK were increased in SHRLN compared with SHR or WKY. Nevertheless, only the strong accumulations of fibronectin and collagen at the AA site in SHRLN were associated with intrinsic stiffening. In conclusion, we confirm that NO restriction associated with hypertension induces a severe pathological phenotype and shows that L-NAME induced stiffening is more pronounced in AA than in TA as a result of greater fibrosis.
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In many individuals, blood pressure varies between clinic visits conducted days, weeks, or months apart. This visit-to-visit variability (VVV) of blood pressure has been recently related with an increased risk of coronary heart disease, stroke, and mortality, independently of mean blood pressure. As for other chronical diseases, patients' adherence to hypertensive therapies remains low and partial adherence to antihypertensive treatment may constitute a source of VVV, as suggested by recent studies. This data should lead to a new clinical approach for hypertension care, based on patients' real adherence to treatment. Therapeutic strategies should include patients' adherence. In this context, the role of community pharmacists for patients' follow-up of hypertension should be reinforced, as they represent efficient and easily accessible health professionals.
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Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Adesão à Medicação , Farmacêuticos/normas , Papel Profissional , Humanos , Hipertensão/fisiopatologia , Hipertensão/psicologia , Adesão à Medicação/psicologia , Metanálise como Assunto , Equipe de Assistência ao Paciente/normas , Ensaios Clínicos Controlados Aleatórios como Assunto/normasRESUMO
Lacosamide, one of the last antiepileptic drugs marketed, can cause extension of PR interval. Precautions are recommended when used in elderly and with other drugs extending PR interval. Cases of severe third-degree atrioventricular block have been reported only in post-marketing case reports when used at high-doses and remain rare. We report the case of an 88-year-old woman treated with bisoprolol, who experienced a complete atrioventricular block after initiation of lacosamide for epilepsy associated with neurodegenerative disease. This dramatic event required a pacemaker implementation. Not being dose-dependent (initiation dosage used), it seemed partially explained by drug-drug interaction with bisoprolol.
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Anticonvulsivantes/efeitos adversos , Bloqueio Atrioventricular/induzido quimicamente , Nó Atrioventricular/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Lacosamida/efeitos adversos , Antagonistas de Receptores Adrenérgicos beta 1/efeitos adversos , Idoso de 80 Anos ou mais , Bloqueio Atrioventricular/diagnóstico , Bloqueio Atrioventricular/fisiopatologia , Bloqueio Atrioventricular/terapia , Nó Atrioventricular/fisiopatologia , Bisoprolol/efeitos adversos , Estimulação Cardíaca Artificial , Interações Medicamentosas , Eletrocardiografia , Feminino , Humanos , Fatores de Risco , Resultado do TratamentoRESUMO
Background Clinical pharmacists' involvement has improved patients' care, by suggesting therapeutic optimizations. However, budget restrictions require a prioritization of these activities to focus resources on patients more at risk of medication errors. Objective The aim of our study was to identify variables influencing the formulation of pharmaceutical to improve medication review efficiency. Setting This study was conducted in medical wards of a 643-acute beds hospital in Paris, France. Methods All hospital medical prescriptions of all patients admitted within four medical wards (cardiology, rheumatology, neurology, vascular medicine) were analyzed. The study was conducted in each ward for 2 weeks, during 4 weeks. For each patient, variables prospectively collected were: age, gender, weight, emergency admission, number of high-alert medications and of total drugs prescribed, care unit, serum creatinine. Number of pharmaceutical interventions (PIs) and their type were reported. Main outcome measures Variables influencing the number of pharmaceutical interventions during medication review were identified using simple and multiple linear regressions. Results A total of 2328 drug prescriptions (303 patients, mean age 70.6 years-old) were analyzed. Mean number of hospital drug prescriptions was 7.9. A total of 318 PIs were formulated. Most frequent PIs were drug omission (n = 88, 27.7%), overdosing (n = 69, 21.7%), and underdosing (n = 51, 16.0%). Among variables studied, age, serum creatinine level, number of high-alert medications prescribed and total number of drugs prescribed were significantly associated with the formulation of pharmaceutical interventions (adjusted R2 = 0.34). Conclusions This study identified variables (age, serum creatinine level, number of high-alert medication, number of prescribed drugs) that may help institutions/pharmacists target their reviews towards patients most likely to require pharmacist interventions.
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Erros de Medicação/prevenção & controle , Conduta do Tratamento Medicamentoso/organização & administração , Farmacêuticos/organização & administração , Serviço de Farmácia Hospitalar/organização & administração , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , França , Humanos , Modelos Lineares , Masculino , Conduta do Tratamento Medicamentoso/normas , Pessoa de Meia-Idade , Padrões de Prática Médica/normas , Padrões de Prática Médica/estatística & dados numéricos , Papel Profissional , Estudos Prospectivos , Adulto JovemRESUMO
Background The benefits of educational programs are recognized in chronic diseases. An education program was designed in our hospital, for hypertensive patients after an acute episode of stroke to prevent stroke recurrence. Objective Evaluate the effects of such program on patient knowledge and blood pressure management. Setting The 12-bed stroke center of the Groupe Hospitalier Paris Saint-Joseph, France. Method An individual educational session was provided to all the patients by the pharmacist a few days after admission. The effectiveness of the session was evaluated using a questionnaire completed by each patient before and after education. The patients had to identify the correct responses and to judge their answer's self-confidence. The answers were ranked based on their accuracy and the surety of the respondent. Reported medication adherence and self-measurement of blood pressure were analyzed as part of the survey. Patient satisfaction with the intervention was also measured by means of a separate questionnaire. Main outcome measure Evolution of response correctness and self-confidence as well as medication adherence and blood pressure self-measurement practice. Results 64 patients were enrolled. Correct response rate increased from 77.9 to 94.1% and the absolutely sure response rate raised from 52.9 to 80.8%. Patient self-confidence was improved mainly for correct responses. Patients reported a better medication adherence and a more frequent practice of blood pressure self-measurement. They were highly satisfied. A negative correlation was found between knowledge evolution and baseline knowledge. Conclusion Education can improve stroke patient knowledge, which may enhance medication adherence and blood pressure control. Such programs should be developed even early after a stroke.
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Hipertensão/terapia , Educação de Pacientes como Assunto , Acidente Vascular Cerebral/terapia , Idoso , Idoso de 80 Anos ou mais , Monitorização Ambulatorial da Pressão Arterial , Estudos de Coortes , Gerenciamento Clínico , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Ataque Isquêmico Transitório/terapia , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Cooperação do Paciente , Satisfação do Paciente , Farmacêuticos , Estudos Prospectivos , Autocuidado , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: To study the frequency and circumstances of patients' use of outpatient medications prescribed by their GP during hospitalization and to assess means of reducing this use. METHOD: A prevalence study of medication use was conducted at Saint Joseph's Hospital in Paris. On one day, we used a specific questionnaire to interview 151 patients in 11 different units about the type and amount of medications they had brought with them to the hospital and the type and amount they had used. RESULTS: Overall, 61% had brought their prescription medication with them, and 36% had used some of it, sometimes without informing the medical staff. In 75% of these cases, these drugs were available from the hospital pharmacy. DISCUSSION: Possible corrective steps include both technological improvements (computerized prescription) and organizational measures: systematic inquiry about and consideration of outpatient prescriptions at admission, use of validated prescription/substitution aids (Comedims), and patient information and education about drug substitutions and interactions.
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Prescrições de Medicamentos/estatística & dados numéricos , Hospitalização , Autoadministração/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Uso de Medicamentos , Feminino , França , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e QuestionáriosRESUMO
RATIONALE, AIMS, AND OBJECTIVES: Intravenous (IV) to oral (PO) drug switch is a challenge for tertiary care institutions for several reasons: catheter-related infections, patient's pain and discomfort or higher costs, and overuse of IV drugs considered as an irrational use of medicines. The objective was to evaluate yearly acetaminophen and proton-pump inhibiters' (PPIs) IV/PO ratios from 2011 to 2015 and to determine their correlation with all drugs IV/PO ratios and their relevance as drug tracers. A secondary objective was to estimate costs savings associated with a IV to PO switch improvement. METHODS: Data on IV and PO consumptions and impact on costs were presented to physicians yearly, followed by the development of a computerized tool and pharmaceutical validation of prescriptions. Intravenous and PO drug consumptions were extracted yearly for all drugs, acetaminophen, and PPIs from 2011-01-01 to 2015-12-31. Acetaminophen and PPIs' IV/PO ratios were compared to IV/PO consumptions for all drugs. Costs savings associated with this switch were calculated yearly by multiplying the difference in average cost per dose by the total number of doses delivered (fixed purchase prices, euros) for both routes. RESULTS: All drugs IV/PO ratio decreased every year to achieve a 16.3% reduction between 2011 and 2015. Acetaminophen and PPIs also decreased respectively by 35.5% and 16.5%. Same tendency of decrease of ratios year by year was noted for all drugs, PPIs, and acetaminophen. Savings for both acetaminophen and PPIs IV/PO switch were over 98 000 for 5 years. CONCLUSIONS: This study demonstrated that acetaminophen IV/PO ratio, easily produced in routine, was a relevant tracer to follow IV/PO switch improvement as it was correlated with all drugs IV/PO ratio. Direct cost savings associated with IV/PO switch improvements were consequent and illustrate well the impact of our approach on the efficiency of therapeutics' management.
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Acetaminofen/administração & dosagem , Acetaminofen/economia , Vias de Administração de Medicamentos , Inibidores da Bomba de Prótons/administração & dosagem , Inibidores da Bomba de Prótons/economia , Administração Intravenosa , Administração Oral , Custos e Análise de Custo , HumanosRESUMO
BACKGROUND: Enhanced aortic stiffness and blood pressure variability (BPV) are independent risk factors for cardiovascular disease and all-cause mortality in man. They are also correlated with increased blood pressure (BP) and/or arterial remodeling. However, the interplay between BP and BPV on the stiffening process is still unclear. Our objectives were to determine the temporal evolution of both BPV and pulse wave velocity (PWV), a surrogate measure of arterial stiffness, using an animal model of remodeling-dependent aortic stiffening. METHOD: We thus, developed a new telemetric technique allowing continuous measurement of PWV in conscious, unrestrained rats. Studies were performed in spontaneously hypertensive rats (SHR) treated for 2 weeks with N-nitro-L-arginine methyl ester, a nitric oxide synthase inhibitor (SHR-LN). BPV was evaluated conventionally or with a new device composed of two pressure transducers in two different sets of rats. This allowed a continuous monitoring of telemetered PWV, systolic (SPV), diastolic (DPV), and pulse pressure variability (PPV). Aortic structure was then characterized by immunohistochemical analysis. RESULTS: SPV, DPV, and PPV were increased in SHR-LN, when calculated by 24-h SD or using average real variability a parameter used to assess short-term variability in man. We observed rapid and simultaneous increases in BP, SPV, and PWV. Interestingly, PPV was the most increased parameter resulting mainly from different time course of SPV and DPV. Structural alterations of the aortic wall were observed, with a eutrophic inward remodeling and accumulation of fibronectin and its two main receptors (α5 and αv integrins). CONCLUSION: This offers unequivocal evidence of a significant relationship between PWV, BPV, and arterial structure.
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Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Rigidez Vascular/fisiologia , Animais , Modelos Cardiovasculares , Análise de Onda de Pulso , RatosRESUMO
We aimed to develop an animal model of long-term blood pressure variability (BPV) and to investigate its consequences on aortic damage. We hypothesized that day-to-day BPV produced by discontinuous treatment of spontaneously hypertensive rats (SHR) by valsartan may increase arterial stiffness. For that purpose, rats were discontinuously treated, 2 days a week, or continuously treated by valsartan (30 mg/kg/d in chow) or placebo. Telemetered BP was recorded during 2 min every 15 min, 3 days a week during 8 weeks to cover the full BP variations in response to the treatment schedule. Pulse wave velocity (PWV) and aortic structure evaluated by immunohistochemistry were investigated in a second set of rats treated under the same conditions. Continuous treatment with valsartan reduced systolic BP (SBP) and reversed the aortic structural alterations observed in placebo treated SHR (decrease of medial cross-sectional area). Discontinuous treatment with valsartan decreased SBP to a similar extent but increased the day-to-day BPV, short term BPV, diastolic blood pressure (DBP), and PWV as compared with continuous treatment. Despite no modifications in the elastin/collagen ratio and aortic thickness, an increase in PWV was observed following discontinuous treatment and was associated with a specific accumulation of fibronectin and its αv-integrin receptor compared with both groups of rats. Taken together the present results indicate that a discontinuous treatment with valsartan is able to induce a significant increase in day-to-day BPV coupled to an aortic phenotype close to that observed in hypertension. This experimental model should pave the way for future experimental and clinical studies aimed at assessing how long-term BPV increases aortic stiffness.
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RATIONALE: Sinoaortic denervated (SAD) and chemically sympathectomized (SNX) rats are characterized by a decrease in arterial distensibility without hypertension and would, thus, be relevant for analyzing arterial wall stiffening independently of blood pressure level. The fibronectin network, which plays a pivotal role in cell-matrix interactions, is a major determinant of arterial stiffness. We hypothesized that in SAD and SNX rats, arterial stiffness is increased, due to alterations of cell-matrix anchoring leading to spatial reorganization of the extracellular matrix. METHODS: The intrinsic elastic properties of the arterial wall were evaluated in vivo by the relationship between incremental elastic modulus determined by echotracking and circumferential wall stress. The changes of cell-extracellular matrix links in the abdominal aorta were evaluated by studying fibronectin, vascular integrin receptors, and ultrastructural features of the aorta by immunochemistry. RESULTS: In both experimental conditions, wall stiffness increased, associated with different modifications of cell-extracellular matrix adhesion. In SAD rats, increased media cross-sectional area was coupled with an increase of muscle cell attachments to its extracellular matrix via fibronectin and its α5-ß1 integrin. In SNX rats, reduced media cross-sectional area was associated with upregulation of αv-ß3 integrin and more extensive connections between dense bands and elastic fibers despite the disruption of the elastic lamellae. CONCLUSION: In aorta of SNX and SAD rats, a similar arterial stiffness is associated to different structural alterations. An increase in αvß3 or α5ß1 integrins together with the already reported increase in the proportion of less distensible (collagen) to more distensible (elastin) components in both models contributes to remodeling and stiffening of the abdominal aorta.
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Aorta Abdominal/inervação , Aorta Abdominal/fisiopatologia , Fibronectinas/metabolismo , Nó Sinoatrial/inervação , Nó Sinoatrial/fisiopatologia , Rigidez Vascular/fisiologia , Animais , Aorta Abdominal/patologia , Denervação , Modelos Animais de Doenças , Matriz Extracelular/fisiologia , Hemodinâmica , Hipertensão/patologia , Hipertensão/fisiopatologia , Integrina alfa5/metabolismo , Masculino , Ratos , Ratos Wistar , Simpatectomia QuímicaRESUMO
BACKGROUND: In France, the proportion of MRSA has been over 25% since 2000. Prevention of hospital-acquired (HA) MRSA spread is based on isolation precautions and antibiotic stewardship. At our institution, before 2000, the Infection Disease and the Infection Control teams had failed to reduce HA-MRSA rates. OBJECTIVES AND METHODS: We implemented a multifaceted hospital-wide prevention program and measured the effects on HA-MRSA colonization and bacteremia rates between 2000 and 2009. From 2000 to 2003, active screening and decontamination of ICU patients, hospital wide alcohol based hand rubs (ABHR) use, control of specific classes of antibiotics, compliance audits, and feed-backs to the care providers were successively implemented. The efficacy of the program was assessed by HA-MRSA colonized and bacteremic patient rates per 1000 patient-days in patients hospitalized for more than twenty-four hours. RESULTS: Compliance with the isolation practices increased between 2000 and 2009. Consumption of ABHR increased from 6.8 L to 27.5 L per 1000 patient-days. The use of antibiotic Defined Daily Doses (DDD) per 1000 patient-days decreased by 31%. HA-MRSA colonization decreased by 84% from 1.09 to 0.17 per 1000 patient-days and HA-MRSA bacteremia by 93%, from 0.15 to 0.01 per 1000 patient-days (p < 10-7 for each rate). CONCLUSIONS: In an area highly endemic for MRSA, a multifaceted prevention program allows for sustainable reduction in HA-MRSA bacteremia rates.
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BACKGROUND: Meta-analyses of antihypertensive therapy suggest that, independently of blood pressure (BP) level, stroke prevention is influenced mainly by calcium-entry blockers (CEB) and cardiac risk prevention by angiotensin-converting enzyme inhibitors (ACEIs). The possibility that central systolic and pulse pressure (PP) reduction differs between the two drug classes for the same mean BP (MBP) has never been explored. Our aim was to compare carotid PP at the same MBP obtained with the CEB, amlodipine, and the ACEI, trandolapril, in spontaneously hypertensive rats (SHR), and to evaluate the resulting changes of fibronectin (Fn) and its integrin alpha5beta1 receptor on central PP and arterial stiffness. METHODS: Amlodipine and trandolapril were administered chronically to achieve the same MBP. Carotid arterial systolic BP (SBP) and PP, diameter and incremental elastic modulus (E(inc)) were determined using echo Doppler techniques, and complemented with vascular histomorphometry, and Fn and alpha5beta1-integrin immunolabeling. RESULTS: Both drugs produced the same MBP, carotid wall thickness, and stress. Trandolapril reduced PP and E(inc) significantly more than amlodipine, while both agents comparably lowered EIIIA-Fn. Total Fn and alpha-subunit were lowered significantly by trandolapril, but unaffected by amlodipine, indicating that ACEI alone contributed to both diminished carotid stiffness and decrease of the Fn-integrin complex. CONCLUSIONS: Results showed that amlodipine and trandolapril have different effects on carotid mechanical properties for comparable MBP reduction. Changes in Fn-integrin complex not only modify consistently ACEI mechanotransduction but also are associated with selective central PP reduction. Whether this property has consequences on cardiovascular (CV) risk remains to be investigated.