Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
1.
Rev Esp Quimioter ; 37(1): 88-92, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37937523

RESUMO

The new automated systems designed for rapid performance of AST have significantly reduced the response time for susceptibility testing of microorganisms causing bacteremia and sepsis. The Accelerate Pheno® system (AAC) is one such system. Our objective for this study was to determine whether the AAC system is capable of providing an accurate susceptibility profile to infer resistance mechanisms in different carbapenemase-producing isolates when compared to the MicroScan WalkAway System (MWS). Disk diffusion method was also performed on all isolates as a reference method. Additionally, we compared the results obtained with the routine AST production system. We selected 19 isolates from the cryobank of the Microbiology department, all of which were carbapenemase-producing gram-negative bacilli. AAC was able to identify and infer the resistance of a total of 10 isolates, with an EA and CA of 84.2% for meropenem and 88.2% and 64.7% for ertapenem EA and CA, respectively. If we consider the disk diffusion technique, the CA was 57.9% and 76.5% for meropenem and ertapenem. However, in the presence of carbapenemases, AAC was not able to provide adequate MICs or infer the resistance mechanisms of the isolates accurately. Further studies with a larger number of isolates, including the new antibiotics ceftolozane/tazobactam and ceftazidime/avibactam, are needed for a more comprehensive comparison.


Assuntos
Antibacterianos , Bactérias Gram-Negativas , Humanos , Meropeném , Ertapenem , Antibacterianos/farmacologia , beta-Lactamases/genética , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa
2.
Plant Sci ; 337: 111870, 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37722506

RESUMO

Ageing in dry chlorophyllous propagules is leaded by photooxidation through the photosynthetic machinery, but why species differ in longevity and the ageing mechanisms of when light and oxygen are absent are unknown. We hypothesize that the cellular antioxidant capacity is key for the inter- and intra-specific differences in the ageing process. We have tested this hypothesis in chlorophyllous spores of two ferns. They were subjected to four different storage regimes resulting from light/dark and normoxia/hypoxia combinations. Lipophilic and hydrophilic antioxidants, reactive oxygen species (ROS), and photosynthetic pigments were analysed in parallel to germination and the recovery of Fv/Fm over a storage period of up to 22-months. We show that light and oxygen accelerate the ageing process, but their mechanisms (ROS, increase, antioxidant capacity decrease, loss of efficiency of the photosystem II, pigment degradation) appear the same under all conditions tested. The end of the asymptomatic phase of longevity, when a sudden drop of germination occurs, seems to be determined by a threshold in the depletion of antioxidants. Our results support the hypothesis that ageing kinetics in dry plant propagules is determined by the antioxidant system, but also suggests an active role of the photosynthetic machinery during ageing, even in darkness and hypoxia.

3.
Med Intensiva (Engl Ed) ; 46(4): 192-200, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35227639

RESUMO

OBJECTIVE: To analyze the variables associated with ICU refusal decisions as a life support treatment limitation measure. DESIGN: Prospective, multicentrico. SCOPE: 62 ICU from Spain between February 2018 and March 2019. PATIENTS: Over 18 years of age who were denied entry into ICU as a life support treatment limitation measure. INTERVENTIONS: None. MAIN INTEREST VARIABLES: Patient comorities, functional situation as measured by the KNAUS and Karnosfky scale; predicted scales of Lee and Charlson; severity of the sick person measured by the APACHE II and SOFA scales, which justifies the decision-making, a person to whom the information is transmitted; date of discharge or in-hospital death, destination for hospital discharge. RESULTS: A total of 2312 non-income decisions were recorded as an LTSV measure of which 2284 were analyzed. The main reason for consultation was respiratory failure (1080 [47.29%]). The poor estimated quality of life of the sick (1417 [62.04%]), the presence of a severe chronic disease (1367 [59.85%]) and the prior functional limitation of patients (1270 [55.60%]) were the main reasons for denying admission. The in-hospital mortality rate was 60.33%. The futility of treatment was found as a risk factor associated with mortality (OR: 3.23; IC95%: 2.62-3.99). CONCLUSIONS: Decisions to limit ICU entry as an LTSV measure are based on the same reasons as decisions made within the ICU. The futility valued by the intensivist is adequately related to the final result of death.


Assuntos
Unidades de Terapia Intensiva , Qualidade de Vida , APACHE , Adolescente , Adulto , Mortalidade Hospitalar , Humanos , Estudos Prospectivos
4.
Rev Esp Quimioter ; 35(3): 284-287, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35355046

RESUMO

OBJECTIVE: Bloodstream infections (BSI) caused by extended-spectrum beta-lactamases Enterobacteriaceae (ESBL-E) are associated with high rates of treatment failure and increased mortality, especially when appropriate antimicrobial therapy is delayed. Our aim was to evaluate the anticipation of ESBLs detection and the potential improvement of the time response of the Vitek 2 System (BioMérieux; France). METHODS: We compared this lateral flow immunoassay when used directly on fluid from positive blood cultures to the VITEK2 AST system. We evaluated 80 isolates, 61 tested directly on fluid from positive blood cultures and 19 tested on fluid from blood cultures spiked with known ESBL positive and negative organisms. RESULTS: The concordance between the CTX-LFIA and the reference method (Vitek 2) had a Cohen´s Kappa coefficient of 0.97, indicating a particularly good correlation between both compared methods. CONCLUSIONS: This lateral flow immunoassay can be more rapid than the Vitek 2 for earlier presumptive identification of CTX-M ESBLs and can be useful to anticipate results and the adjustment of antimicrobial therapy.


Assuntos
Gestão de Antimicrobianos , Infecções por Enterobacteriaceae , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Hemocultura , Infecções por Enterobacteriaceae/tratamento farmacológico , Humanos , Imunoensaio , Testes de Sensibilidade Microbiana , beta-Lactamases
5.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33386143

RESUMO

OBJECTIVE: To analyze the variables associated with ICU refusal decisions as a life support treatment limitation measure. DESIGN: Prospective, multicentrico SCOPE: 62 ICU from Spain between February 2018 and March 2019. PATIENTS: Over 18 years of age who were denied entry into ICU as a life support treatment limitation measure. INTERVENTIONS: None. MAIN INTEREST VARIABLES: Patient comorities, functional situation as measured by the KNAUS and Karnosfky scale; predicted scales of Lee and Charlson; severity of the sick person measured by the APACHE II and SOFA scales, which justifies the decision-making, a person to whom the information is transmitted; date of discharge or in-hospital death, destination for hospital discharge. RESULTS: A total of 2312 non-income decisions were recorded as an LTSV measure of which 2284 were analyzed. The main reason for consultation was respiratory failure (1080 [47.29%]). The poor estimated quality of life of the sick (1417 [62.04%]), the presence of a severe chronic disease (1367 [59.85%]) and the prior functional limitation of patients (1270 [55.60%]) were the main reasons for denying admission. The in-hospital mortality rate was 60.33%. The futility of treatment was found as a risk factor associated with mortality (OR: 3.23; IC95%: 2.62-3.99). CONCLUSIONS: Decisions to limit ICU entry as an LTSV measure are based on the same reasons as decisions made within the ICU. The futility valued by the intensivist is adequately related to the final result of death.

6.
Med Intensiva (Engl Ed) ; 43(2): 73-78, 2019 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29428185

RESUMO

OBJECTIVE: To assess the correlation between left ventricular outflow tract velocity time integral (LVOT VTI) and stroke volume index (SVI) calculated by thermodilution methods in ventilated critically ill patients. DESIGN: A prospective, descriptive, multicenter study was performed. SETTING: Five intensive care units from university hospitals. PATIENTS: Patients older than 17 years needing mechanical ventilation and invasive hemodynamic monitoring were included. INTERVENTIONS: LVOT VTI was measured by pulsatile Doppler echocardiography. Calculations of SVI were performed through a floating pulmonary artery catheter (PAC) or a Pulse index Contour Cardiac Output (PiCCO®) thermodilution methods. MAIN VARIABLES: The relation between LVOT VTI and SVI was tested by linear regression analysis. RESULTS: One hundred and fifty-six paired measurements were compared. Mean LVOT VTI was 20.83±4.86cm and mean SVI was 41.55±9.55mL/m2. Pearson correlation index for these variables was r=0.644, p<0.001; ICC was 0.52 (CI 95% 0.4-0.63). When maximum LVOT VTI was correlated with SVI, Pearson correlation index was r=0.62, p<0.001. Correlation worsened for extreme values, especially for those with higher LVOT VTI. CONCLUSIONS: LVOT VTI could be a complementary hemodynamic evaluation in selected patients, but does not eliminate the need for invasive monitoring at the present time. The weak correlation between LVOT VTI and invasive monitoring deserves additional assessment to identify the factors affecting this disagreement.


Assuntos
Respiração Artificial , Volume Sistólico , Função Ventricular Esquerda , Idoso , Velocidade do Fluxo Sanguíneo , Correlação de Dados , Feminino , Humanos , Masculino , Estudos Prospectivos
7.
Folia Morphol (Warsz) ; 78(2): 394-400, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30299534

RESUMO

BACKGROUND: The accessory head of the flexor pollicis longus (AHFPL) has an oblique trajectory from medial to lateral aspect of the forearm below the flexor digitorum superficialis muscle and then joins the flexor pollicis longus muscle. When the anterior interosseous nerve (AIN) courses underneath the muscle belly of the AHFPL an entrapment neuropathy may occur, known as anterior interosseous nerve syndrome (AINS). MATERIALS AND METHODS: This descriptive cross-sectional study evaluated 106 fresh upper extremities. When the AHFPL was present, its fascicle was traced up to evaluate the origin site. The morphometric variables were measured using a digital micrometre (Mitutoyo, Japan). The relationship between the AHFLP and the AIN was evaluated. RESULTS: The AHFPL was found in 34 (32.1%) of the 106 forearms. The AHFPL arose from the flexor digitorum superficialis muscle in 16 (47.1%) forearms, the medial epicondyle of the humerus in 10 (29.4%) forearms and the coronoid process of ulna in 8 (23.5%) forearms. The average total length of the AHFPL was 94.11 ± ± 10.33 mm. The AIN was located lateral to the AHFPL in 3 (8.8%) forearms, posterolateral in 7 (20.6%) forearms and posterior in 24 (70.6%) forearms. CONCLUSIONS: This study performed in a South American population sample revealed a prevalence of the AHFPL in a lower range compared to previous studies in North Americans and Asians. The AIN coursed more frequently underneath the muscle belly of AHFPL. This finding has clinical significance in the onset of the AINS and the subsequent surgical procedure for the AIN decompression.


Assuntos
Músculo Esquelético/anatomia & histologia , Animais , Membro Anterior/anatomia & histologia , Humanos , Masculino
8.
Rev. mex. ing. bioméd ; 38(1): 54-75, ene.-abr. 2017. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-902328

RESUMO

Resumen: En este trabajo se presenta, la caracterización mediante las técnica de Infrarrojo, Microscopía de Fuerza Atómica, Microscopía Electrónica de Barrido y ángulo de contacto de los recubrimientos poliméricos de la mezcla binaria de policaprolactona-quitosano y su modificación tras la adición de colágeno que fueron depositados mediante la técnica de Dip Coating sobre la aleación de Ti6Al4V; además, se evaluó mediante la técnica de Espectroscopía de Impedancia Electroquímica la aleación Ti6Al4V recubierta por las mezclas de polímeros a cero días de inmersión en Fluido Corporal Simulado y la capacidad de adsorción de calcio a 21 días de inmersión. De esta manera, se encontraron efectos representativos sobre el papel del colágeno para el aumento de la rugosidad superficial, mayores valores en la resistencia a la polarización del Ti6Al4V, mejor comportamiento en los parámetros de energía libre, adsorción atómica de calcio y la consolidación de una nueva interfase asociada a la monocapa de calcio simulada mediante circuitos equivalentes y observada por Microscopía Electrónica de Barrido.


Abstract: This paper presents the characterization by the infrared technique, atomic force microscopy, scanning electron microscopy and contact angle of the polymer coatings of the binary mixture of polycaprolactone-chitosan and its modification after addition of collagen were deposited by the technique of Dip Coating on Ti6Al4V alloy; also by the technique of Electrochemical Impedance Spectroscopy were evaluated the Ti6Al4V alloy coated by polymer blends zero days immersion in Simulate Bode Fluid and of adsorptivity calcium to 21 days immersion. Thus, representative effects on the role of collagen to increase the surface roughness, higher values in the polarization resistance of Ti6Al4V, better behavior parameters free energy, atomic adsorption of calcium and the consolidation of a found new interface associated with the monolayer calcium simulated by equivalent circuits and observed by Scanning Electron Microscopy.

9.
Cryo Letters ; 38(4): 278-289, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29734429

RESUMO

BACKGROUND: The low temperature of liquid nitrogen is assumed to stop ageing and preserve viability indefinitely, however there are few validating data sets. The use of seeds to test these assumptions is important because other cryopreserved systems lack quantitative measures of viability to allow comparisons among timed points. OBJECTIVE: To evaluate survival of a collection of seeds with short lifespans stored 12-20 years in liquid nitrogen. MATERIALS AND METHODS: Seeds from 11 species (26 accessions) were removed from cryostorage and evaluated for germination and normal growth. RESULTS: Germination of Plantago cordata and Betula spp. seeds did not decrease significantly during cryostorage. However, Populus deltoides and most Salix spp. accessions showed a significant decrease in germination, with further loss observed when P. deltoides seedlings were followed to the young plant stage. Seeds of initial low quality showed greater deterioration during cryostorage. CONCLUSION: Cryostorage maintained viability of Salix and Populus seeds longer than other temperatures. However, ageing was not completely stopped and seed longevity was shorter than that predicted for many other species. A high initial seed quality is important in order to obtain the maximum benefit of cryostorage.


Assuntos
Criopreservação/métodos , Nitrogênio/farmacologia , Plantas/metabolismo , Sementes/fisiologia , Dessecação , Germinação/efeitos dos fármacos , Desenvolvimento Vegetal/efeitos dos fármacos , Plântula/efeitos dos fármacos , Plântula/fisiologia , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Temperatura , Fatores de Tempo , Sobrevivência de Tecidos/efeitos dos fármacos
10.
Int. j. morphol ; 34(1): 404-409, Mar. 2016. ilus
Artigo em Espanhol | LILACS | ID: lil-780524

RESUMO

Se presenta un raro caso de múltiples variaciones en la cavidad abdominal de un espécimen cadavérico de 50 años de género masculino, del laboratorio de anatomía de la Universidad Industrial de Santander (Bucaramanga-Colombia). Se observó variaciones arteriales (arteria renal adicional derecha y origen de la rama hepática derecha desde la arteria mesentérica superior), venosa (vena renal derecha adicional) y de vía urinaria (doble uréter en el lado derecho). Estas diversas variantes anatómicas además de suscitar interés académico, deben ser consideradas y descritas correctamente por los clínicos durante la realización de procedimientos quirúrgicos, radiológicos y de imágenes diagnósticas en la cavidad abdominal.


Here we present a rare case of multiple abdominal cavity variations in a 50-year-old male cadaveric specimen of the anatomy laboratory of the Universidad Industrial de Santander (Bucaramanga, Colombia). The anatomical dissection revealed arterial variations (right additional renal artery and origin of the right hepatic branch from the superior mesenteric artery), venous (right additional renal vein) and urinary tract (duplicated ureter on the right side). These multiple anatomic variations in addition to raising academic interest, should be considered and described correctly by clinicians while performing surgical, radiological and imaging procedures in the abdominal cavity.


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Cavidade Abdominal/irrigação sanguínea , Variação Anatômica , Artéria Hepática/anormalidades , Artéria Renal/anormalidades , Veias Renais/anormalidades
11.
Med Intensiva ; 40(3): 139-44, 2016 Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26725105

RESUMO

OBJECTIVES: Due to the increase in isolation of Candida spp. in critically ill patients, and the high mortality and economic costs which this infection entails, a study was made of the risk factors associated to candidemia in critically ill patients from 7 intensive care units in Colombia. MATERIALS AND METHODS: A multicenter matched case-control study was conducted in 7 intensive care units of 3 university hospitals. Data on overall length of hospital stay (including both general wards and the intensive care unit) were recorded. RESULTS: A total of 243 subjects (81 cases and 162 controls) between January 2008 and December 2012 were included. In order of frequency, C. albicans, C. tropicalis and C. parapsilosis were isolated. The main identified risk factors were: overall length of hospital stay>25 days (OR 5.33, 95% CI 2.6-10.9), use of meropenem (OR 3.75, 95% CI 1.86-7.5), abdominal surgery (OR 2.9, 95% CI 1.39-6.06) and hemodialysis (OR 3.35, 95% CI 1.5-7.7). No differences in mortality between patients with candidemia and controls were found (39.5 vs. 36.5%, respectively, P=.66) were found. CONCLUSIONS: In Colombia, a long hospital stay, abdominal surgery, the use of meropenem and hemodialysis were identified as risk factors for candidemia.


Assuntos
Candidemia/etiologia , Candidíase/etiologia , Estado Terminal , Antifúngicos/uso terapêutico , Candidíase/tratamento farmacológico , Estudos de Casos e Controles , Colômbia , Infecção Hospitalar , Humanos , Incidência , Tempo de Internação , Fatores de Risco
12.
Med Intensiva ; 39(7): 405-11, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25499901

RESUMO

BACKGROUND: Intermittent glycemic measurements in patients admitted to the intensive care unit (ICU) can result in episodes of severe hypoglycemia or in a poor control of glycemia range. We designed a study to assess accuracy and reliability of continuous monitoring of tissue glucose for patients with distributive shock. METHODS: Consecutive patients admitted to the ICU with a diagnosis of distributive shock and the need of insulin infusion for glycemic control were included in the study. These patients were implanted a Continuous Glucose Control Monitoring System (CGMS) with the sensor inserted subcutaneously into the abdominal wall. CGMS values were recorded every 5min. Capillary glucose (CG) was monitored for adjusting insulin perfusion according to the ICU protocol. Correlation between both methods was assessed. RESULTS: A total of 11,673 CGMS and 348 CG values were recorded. In five patients, CGMS failed to detect tissue glucose. A glucose value <3.33mmol/l (<60mg/dl) was observed in 3.6% of CGMS and in 0.29% CG values. 295 pairs of measurements were included in the statistical analysis for correlation assessment. The intraclass correlation coefficient was 0.706. The Pearson correlation coefficient was 0.71 (p<0.0001, 95% CI 0.65-0.76). The mean of differences between both measurement methods was 0.22mmol/l (3.98mg/dl) (95% CI 0.66-7.31). CONCLUSIONS: When the Continuous Glucose Control Monitoring System (CGMS) is able to obtain data (75% of the patients), there is correlation between the values obtained by this method and capillary blood glucose in patients with distributive shock. CGMS can detect more episodes of glycemic excursions outside the normal range than intermittent capillary glucose monitoring. Variables that may impair glucose metabolism and peripheral soft tissues perfusion could impair CGMS measurements.


Assuntos
Cuidados Críticos/métodos , Líquido Extracelular/química , Glucose/análise , Monitorização Fisiológica/métodos , Choque Séptico/sangue , Parede Abdominal , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Glicemia/análise , Capilares , Eletrodos Implantados , Feminino , Humanos , Hiperglicemia/sangue , Hiperglicemia/diagnóstico , Hiperglicemia/tratamento farmacológico , Hiperglicemia/etiologia , Hipoglicemia/sangue , Hipoglicemia/induzido quimicamente , Hipoglicemia/diagnóstico , Hipoglicemia/prevenção & controle , Insulina/efeitos adversos , Insulina/uso terapêutico , Unidades de Terapia Intensiva , Pessoa de Meia-Idade , Monitorização Fisiológica/instrumentação , Pancreatite/sangue , Pancreatite/complicações , Reprodutibilidade dos Testes , Choque Séptico/complicações , Tela Subcutânea , Adulto Jovem
13.
Med Intensiva ; 38(9): 533-40, 2014 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-25438874

RESUMO

OBJECTIVE: To determine tolerance, pain intensity, percentage of tests completed successfully and complications of deep sedation controlled by intensivists during gastrointestinal endoscopic procedures. DESIGN: A one-year, prospective observational study was carried out. SETTING: Department of Intensive Care intervention in the Endoscopy Unit of Hospital Universitario del Tajo (Spain). PATIENTS: Subjects over 15 years of age subjected to endoscopic procedures under deep sedation. RESULTS: A total of 868 patients were sedated during the study period, with the conduction of 1010 endoscopic procedures. The degree of tolerance was considered adequate («Very good¼/«Good¼) in 96.9% of the patients (95%CI: 95.7-98.1%), with a median score of 0 on the pain visual analog scale. A total of 988 endoscopic procedures were successfully completed (97.8%; 95%CI: 96.9-98.8%): 675 colonoscopies (97.1%) and 305 endoscopies (99.7%). Complications were recorded in 106 patients (12.2%; 95%CI: 10.0-14.5%). The most frequent being desaturation (6.1%), rhythm disturbances (5.1%) and hypotension (2.4%). CONCLUSION: Gastrointestinal endoscopic procedures under sedation controlled by intensivists are well tolerated and satisfactory for the patient, and are successfully completed in a very large percentage of cases. The procedures are associated with frequent minor complications that are resolved successfully.


Assuntos
Cuidados Críticos , Sedação Profunda , Endoscopia Gastrointestinal , Endoscopia Gastrointestinal/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
14.
Cryo Letters ; 32(2): 89-98, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21766138

RESUMO

Green spores of ferns lose viability quickly, and need specialized treatment for long-term conservation in germplasm banks. Dry storage at different temperatures was studied in green spores of Osmunda regalis and Equisetum ramosissimum. Changes in germination percentage, time to 50 percent of maximum germination (T50) and tendency for normal growth of the gametophyte were assayed during 24 months of storage. Spores stored at 25 degree C died within 1 month. Spores stored at 4 degree C maintained high viability for about 3 months, and then aging was evident by a decrease of final germination percentage, an increase in T50, and abnormal development of the gametophyte. Germination of spores stored at -25 degree C was highly variable during the storage period. Spores cryopreserved at -80 degree C and -196 degree C maintained high viability, rapid germination and normal growth throughout the study period. Cryopreservation of green spores is a feasible method to preserve viability and ensure normal gametophyte development for several years.


Assuntos
Criopreservação , Congelamento , Esporos/crescimento & desenvolvimento , Bancos de Espécimes Biológicos , Sobrevivência Celular , Senescência Celular , Temperatura Baixa , Gleiquênias/citologia , Gleiquênias/crescimento & desenvolvimento , Células Germinativas Vegetais/citologia , Células Germinativas Vegetais/crescimento & desenvolvimento , Germinação , Esporos/citologia
15.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 2195-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17946503

RESUMO

One of the challenges in intensive care is the process of weaning from mechanical ventilation. We studied the differences in respiratory pattern variability between patients capable of maintaining spontaneous breathing during weaning trials and patients that fail to maintain spontaneous breathing. In this work, neural networks were applied to study these differences. 64 patients from mechanical ventilation are studied: Group S with 32 patients with Successful trials and Group F with 32 patients that Failed to maintain spontaneous breathing and were reconnected. A performance of 64.56% of well classified patients was obtained using a neural network trained with the whole set of 35 features. After the application of a feature selection procedure (backward selection) 84.56% was obtained using only 8 of the 35 features.


Assuntos
Diagnóstico por Computador/métodos , Redes Neurais de Computação , Testes de Função Respiratória/métodos , Insuficiência Respiratória/diagnóstico , Insuficiência Respiratória/reabilitação , Terapia Assistida por Computador/métodos , Desmame do Respirador/métodos , Humanos , Reconhecimento Automatizado de Padrão/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 5587-90, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17947151

RESUMO

One of the most frequent reasons for instituting mechanical ventilation is to decrease patient's work of breathing. Many attempts have been made to increase the effectiveness of the evaluation of the respiratory pattern with the analysis of the respiratory signals. This work proposes a method for the study of the differences in respiratory pattern variability in patients on weaning trials. The proposed method is based on a support vector machine using 35 features extracted from the respiratory flow signal. In this paper, a group of 146 patients with mechanical ventilation were studied: group S of 79 patients with successful weaning trials and group F of 67 patients that failed to maintain spontaneous breathing and were reconnected. Applying a feature selection procedure based on the use of the support vector machine with a leave-one-out cross-validation, it was obtained 86.67% of well classified patients on group S and 73.34% on group F, using only 8 of the 35 features. Therefore, support vector machine can be a classification method of the respiratory pattern variability useful in the study of patients on weaning trials.


Assuntos
Insuficiência Respiratória/terapia , Desmame do Respirador/métodos , Algoritmos , Análise por Conglomerados , Técnicas de Apoio para a Decisão , Desenho de Equipamento , Humanos , Modelos Estatísticos , Modelos Teóricos , Reprodutibilidade dos Testes , Respiração , Respiração Artificial , Software , Fatores de Tempo , Desmame do Respirador/instrumentação , Trabalho Respiratório
17.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 4576-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17281258

RESUMO

Assessing autonomic control provides information about patho-physiological imbalances. Measures of variability of the cardiac interbeat duration RR(n) and the variability of the breath duration TTot(n) are sensitive to those changes. The interactions between RR(n) and TTot(n) are complex and strongly non-linear. A study of joint symbolic dynamics is presented as a new short-term non-linear analysis method to investigate these interactions in patients on weaning trials. 78 patients from mechanical ventilation are studied: Group A (patients that failed to maintain spontaneous breathing and were reconnected) and Group B (patients with successful trials). Using the concept of joint symbolic dynamics, cardiac and respiratory changes were transformed into a word series, and the probability of occurrence of each word type was calculated and compared between both groups. Significant differences were found in 13 words, and the most significant pn(Wc010, r010): 0.0041 ± 0.0036 (group A) against 0.0012 ± 0.0024 (group B), p-value = 0.00001. The number of seldom occurring word types (forbidden words) also presents significant differences fwcr: 6.9 ± 6.6 against 13.5 ± 5.3, p-value = 0.00004. Joint symbolic dynamics provides an efficient non-linear representation of cardiorespiratory interactions that offers simple physiological interpretations.

18.
J Hosp Infect ; 56(3): 175-83, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15003664

RESUMO

A prospective trial was undertaken to assess the effectiveness and safety of enteral vancomycin in controlling methicillin-resistant Staphylococcus aureus (MRSA) in an endemic setting. Over the 49 month period patients aged >14 years were enrolled, following admission to a medical/surgical intensive care unit (ICU) and expected to require ventilation for three days or more. A total of 799 patients were included in the trial. Period one, 1 July 1996-30 April 1997, (N=140), was observational. During period two, 1 May 1997-30 September 1998, (N=258), surveillance samples were obtained. MRSA carriers were isolated and received enteral vancomycin. During period three, 1 October 1998-31 July 2000, (N=400), all ventilated patients were given selective digestive decontamination (SDD) with polymyxin E, tobramycin, amphotericin B and vancomycin and four days of intravenous cefotaxime. The primary endpoints were: (1) incidence of patients with diagnostic samples positive for MRSA acquired on the ICU; (2) incidence of patients with vancomycin-resistant enterococci (VRE) in surveillance or diagnostic samples; (3) incidence of patients with samples positive for S. aureus with intermediate sensitivity to glycopeptides (GISA). The incidence of patients with MRSA in diagnostic samples were 31%, 14%, and 2% in periods one, two and three, respectively (P<0.001). There was a VRE outbreak involving 13 patients during period three. VRE disappeared with no change in policy. GISA was not detected. These findings support the effectiveness and safety of enteral vancomycin in the control of MRSA.


Assuntos
Antibacterianos/administração & dosagem , Doenças Endêmicas/prevenção & controle , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus , Vancomicina/administração & dosagem , Idoso , Vias de Administração de Medicamentos , Feminino , Humanos , Controle de Infecções/métodos , Unidades de Terapia Intensiva , Masculino , Resistência a Meticilina , Pessoa de Meia-Idade , Estudos Prospectivos , Respiração Artificial , Infecções Estafilocócicas/epidemiologia , Resultado do Tratamento
19.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 3909-12, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-17271151

RESUMO

Mechanical ventilators are used to provide life support in patients with respiratory failure. One of the challenges in intensive care is the process of weaning from mechanical ventilation. We studied the differences in respiratory pattern variability between patients capable of maintaining spontaneous breathing during weaning trials and patients that fail to maintain spontaneous breathing. The respiratory pattern was characterized by the following time series: inspiratory time (T(I)), expiratory time (T(E)), breath duration (T(Tot)), tidal volume (V(T)), fractional inspiratory time (T(I)/T(Tot)), mean inspiratory flow (V(T)/T(I)), respiratory frequency (f), and rapid shallow breathing index (f/V(T)). The variational activity of breathing was partitioned into autoregressive, periodic and white noise fractions. Patients with unsuccessful trial presented a tendency to higher values of gross variability of V(T)/T(I) and f/V(T), and lower values of T(I). The autocorrelation coefficients tended to present higher values for T(I), T(I)/T(Tot) and V(T)/T(I). During both successful and unsuccessful T-tube test uncorrelated random behavior constituted > 75% of the variance of each time breath components and represented 50 to 70% in the breath component related to V(T). Correlated behavior represented 6 to 21% in time components and 28 to 50% in component related to V(T).

20.
Resuscitation ; 48(2): 111-6, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11426472

RESUMO

OBJECTIVE: To assess the impact (defined not only with regard to patient outcome but also to record keeping for evaluation of care) of a formal, structured resuscitation team for in-hospital cardiopulmonary resuscitation over the year following its creation. METHODS: This is a "before and after" study in which charts of all patients needing resuscitation during the two-year period were reviewed and data arranged in the Utstein Style of in-hospital reporting of cardiac arrests. The review was limited to adults (> or = 18 years of age) in nonICU settings. RESULTS: A total of 220 events were identified. Demographics and presenting rhythms for the two periods under review were similar. For the period of August 1996-August 1997 (group 1), there were 70 resuscitation events recorded with a return of spontaneous circulation (ROSC) rate of 21/70 (30%). For the period of August 1997-August 1998 (group 2), 150 events were recorded and the ROSC rate was significantly higher 87/150 (58%)) (P=0.0002). ROSC after ventricular fibrillation and ventricular tachycardia was similar in both groups (50 vs 57%) (P = 1.00) but an improvement in survival was seen in group 2 from events of bradycardia perfusing rhythm (25% vs 84%) (P = 0.0003). Survival from PEA/Asystole was also improved during period 2 (18 vs 48%) (P = 0.013). Survival to discharge was seen in 3/50 (6%) of patients in period 1 and 18/102 (18%) of patients in period 2 (P = 0.09). CONCLUSIONS: The formation of a structured, formalized hospital resuscitation team was associated with an increase in the number of recorded events, in the number of patients experiencing ROSC and in the percentage of patients who were discharged from the hospital. Facilities with no formal resuscitation team or with no skilled, practiced resuscitator on their current team should consider implementation of a similar strategy.


Assuntos
Reanimação Cardiopulmonar/mortalidade , Reanimação Cardiopulmonar/métodos , Causas de Morte , Parada Cardíaca/mortalidade , Parada Cardíaca/terapia , Mortalidade Hospitalar/tendências , Equipe de Assistência ao Paciente/organização & administração , Adulto , Distribuição por Idade , Idoso , California/epidemiologia , Feminino , Humanos , Incidência , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Probabilidade , Estudos Retrospectivos , Sensibilidade e Especificidade , Distribuição por Sexo , Análise de Sobrevida
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA