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1.
N Engl J Med ; 375(25): 2446-2456, 2016 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-28002709

RESUMEN

BACKGROUND: Limiting the duration of antimicrobial treatment constitutes a potential strategy to reduce the risk of antimicrobial resistance among children with acute otitis media. METHODS: We assigned 520 children, 6 to 23 months of age, with acute otitis media to receive amoxicillin-clavulanate either for a standard duration of 10 days or for a reduced duration of 5 days followed by placebo for 5 days. We measured rates of clinical response (in a systematic fashion, on the basis of signs and symptomatic response), recurrence, and nasopharyngeal colonization, and we analyzed episode outcomes using a noninferiority approach. Symptom scores ranged from 0 to 14, with higher numbers indicating more severe symptoms. RESULTS: Children who were treated with amoxicillin-clavulanate for 5 days were more likely than those who were treated for 10 days to have clinical failure (77 of 229 children [34%] vs. 39 of 238 [16%]; difference, 17 percentage points [based on unrounded data]; 95% confidence interval, 9 to 25). The mean symptom scores over the period from day 6 to day 14 were 1.61 in the 5-day group and 1.34 in the 10-day group (P=0.07); the mean scores at the day-12-to-14 assessment were 1.89 versus 1.20 (P=0.001). The percentage of children whose symptom scores decreased more than 50% (indicating less severe symptoms) from baseline to the end of treatment was lower in the 5-day group than in the 10-day group (181 of 227 children [80%] vs. 211 of 233 [91%], P=0.003). We found no significant between-group differences in rates of recurrence, adverse events, or nasopharyngeal colonization with penicillin-nonsusceptible pathogens. Clinical-failure rates were greater among children who had been exposed to three or more children for 10 or more hours per week than among those with less exposure (P=0.02) and were also greater among children with infection in both ears than among those with infection in one ear (P<0.001). CONCLUSIONS: Among children 6 to 23 months of age with acute otitis media, reduced-duration antimicrobial treatment resulted in less favorable outcomes than standard-duration treatment; in addition, neither the rate of adverse events nor the rate of emergence of antimicrobial resistance was lower with the shorter regimen. (Funded by the National Institute of Allergy and Infectious Diseases and the National Center for Research Resources; ClinicalTrials.gov number, NCT01511107 .).


Asunto(s)
Combinación Amoxicilina-Clavulanato de Potasio/administración & dosificación , Antiinfecciosos/administración & dosificación , Otitis Media/tratamiento farmacológico , Enfermedad Aguda , Combinación Amoxicilina-Clavulanato de Potasio/efectos adversos , Antiinfecciosos/efectos adversos , Esquema de Medicación , Farmacorresistencia Bacteriana , Femenino , Haemophilus influenzae/aislamiento & purificación , Humanos , Lactante , Masculino , Nasofaringe/microbiología , Pronóstico , Streptococcus pneumoniae/aislamiento & purificación , Insuficiencia del Tratamiento
3.
J Vasc Surg ; 74(6): 1956-1957, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34809811
7.
J Vasc Surg ; 71(6): 2107, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32446514
8.
J Vasc Surg ; 61(3): 683-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25499711

RESUMEN

OBJECTIVE: Rapid and objective preoperative assessment of patients undergoing carotid endarterectomy (CEA) remains problematic. Preoperative variables correlate with increased morbidity and mortality, yet no easily implemented tool exists to stratify patients. We determined the relationship between our fully implemented frailty-based bedside Risk Analysis Index (RAI) and complications after CEA. METHODS: Patients undergoing CEA in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database from 2005 to 2011 were included. Variables of frailty RAI were matched to preoperative NSQIP variables, and outcomes including stroke, mortality, myocardial infarction (MI), and length of stay were analyzed. We further analyzed patients who were symptomatic and asymptomatic before CEA. RESULTS: With use of the NSQIP database, 44,832 patients undergoing CEA were analyzed (17,696 [39.5%] symptomatic; 27,136 [60.5%] asymptomatic). Increasing frailty RAI score correlated with increasing stroke, death, and MI (P < .0001) as well as with length of stay. RAI demonstrated increasing risk of stroke and death on the basis of risk stratification (low risk [0-10], 2.1%; high risk [>10], 5.0%). Among patients undergoing CEA, 88% scored low (<10) on the RAI. In symptomatic patients, the risk of stroke and death for patients with a score of ≤10 is 2.9%, whereas if the RAI score is 11 to 15, it is 5.0%; 16 to 20, 6.9%; and >21, 8.6%. In asymptomatic patients, the risk of stroke and death for patients with a score of ≤10 is 1.6%, whereas if the RAI score is 11 to 15, it is 2.9%; 16 to 20, 5.2%; and >21, 6.2%. CONCLUSIONS: Frailty is a predictor of increased stroke, mortality, MI, and length of stay after CEA. An easily implemented RAI holds the potential to identify a limited subset of patients who are at higher risk for postoperative complications and may not benefit from CEA.


Asunto(s)
Enfermedades de las Arterias Carótidas/cirugía , Técnicas de Apoyo para la Decisión , Endarterectomía Carotidea/efectos adversos , Indicadores de Salud , Estado de Salud , Anciano , Anciano de 80 o más Años , Enfermedades Asintomáticas , Enfermedades de las Arterias Carótidas/complicaciones , Enfermedades de las Arterias Carótidas/diagnóstico , Enfermedades de las Arterias Carótidas/mortalidad , Bases de Datos Factuales , Endarterectomía Carotidea/mortalidad , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Infarto del Miocardio/etiología , Infarto del Miocardio/mortalidad , Selección de Paciente , Valor Predictivo de las Pruebas , Medición de Riesgo , Factores de Riesgo , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/mortalidad , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos
9.
Ann Surg ; 260(1): 65-71, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24263326

RESUMEN

OBJECTIVE: This report describes the development, initial implementation, and reliability of American College of Surgeons Resident Objective Structured Clinical Examination (ACS OSCE). BACKGROUND: Variability in clinical knowledge and skills of entering surgery residents has been demonstrated. The ACS OSCE was developed to evaluate and help remediate residents' knowledge and skills in managing patients with life-threatening conditions. METHODS: A task force of surgeons and professional educators developed 10 standardized clinical case stations, evaluation checklists, and rating scales. Standardized patients (SPs) evaluated each resident's clinical skills (history taking, physical examination, communication, and SP-global scores). Residents completed checklists on diagnosis and management. Coefficient alpha and item-total correlations were used, respectively, to assess internal consistency of metrics and station validity. The resident's overall performance for each station was calculated by combining scores of the individual skills. Analysis of variance compared performance across different institutions. RESULTS: A total of 103 postgraduate year 1 residents from 7 institutions completed the OSCE. Reliability coefficients of skills ranged from 0.38 for diagnosis to 0.68 for global scores. For overall performance on individual stations, the reliability coefficients ranged from 0.51 to 0.82. Using total percent correct scores from highly reliable stations (α > 0.8), wide variability in resident performance was demonstrated within and between the 7 institutions. CONCLUSIONS: The ACS OSCE was successfully implemented across diverse institutions. It had moderate reliability and demonstrated variability among entering surgery residents. The ACS OSCE is now available for broader implementation. It should help reduce resident variability and address the requirements of Accreditation Council for Graduate Medical Education for resident supervision.


Asunto(s)
Competencia Clínica , Educación Médica Continua/métodos , Cirugía General/educación , Internado y Residencia/métodos , Médicos/estadística & datos numéricos , Evaluación de Programas y Proyectos de Salud , Especialidades Quirúrgicas/educación , Evaluación Educacional , Humanos , Reproducibilidad de los Resultados , Estados Unidos
10.
J Vasc Surg ; 69(2): 515-516, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30683198
11.
Ann Surg ; 258(6): 1096-102, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23511839

RESUMEN

OBJECTIVE: The objective of this study was to assess the impact of preoperative anemia (hematocrit <39%) on postoperative 30-day mortality and adverse cardiac events in patients 65 years or older undergoing elective vascular procedures. BACKGROUND: Preoperative anemia is associated with adverse outcomes after cardiac surgery, but its association with postoperative outcomes after open and endovascular procedures is not well established. Elderly patients have a decreased tolerance to anemia and are at high risk for complications after vascular procedures. METHODS: Patients (N = 31,857) were identified from the American College of Surgeons' 2007-2009 National Surgical Quality Improvement Program-a prospective, multicenter (>250) database maintained across the United States. The primary and secondary outcomes of interest were 30-day mortality and a composite end point of death or cardiac event (cardiac arrest or myocardial infarction), respectively. RESULTS: Forty-seven percent of the study population was anemic. Anemic patients had a postoperative mortality and cardiac event rate of 2.4% and 2.3% in contrast to the 1.2% and 1.2%, respectively, in patients with hematocrit within the normal range (P < 0.0001). On multivariate analysis, we found a 4.2% (95% confidence interval, 1.9-6.5) increase in the adjusted risk of 30-day postoperative mortality for every percentage point of hematocrit decrease from the normal range. CONCLUSIONS: The presence and degree of preoperative anemia are independently associated with 30-day death and adverse cardiac events in patients 65 years or older undergoing elective open and endovascular procedures. Identification and treatment of anemia should be important components of preoperative care for patients undergoing vascular operations.


Asunto(s)
Anemia/complicaciones , Procedimientos Quirúrgicos Electivos/mortalidad , Cardiopatías/epidemiología , Complicaciones Posoperatorias/epidemiología , Procedimientos Quirúrgicos Vasculares/mortalidad , Anciano , Femenino , Humanos , Masculino , Periodo Preoperatorio , Pronóstico , Estudios Prospectivos , Factores de Riesgo
12.
J Vasc Surg ; 57(6): 1589-96, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23395207

RESUMEN

OBJECTIVE: Recent single-center reports demonstrate a high (up to 10%) incidence of postoperative venous thromboembolism (VTE) after major vascular surgery. Moreover, vascular patients rarely receive prolonged prophylaxis despite evidence that it reduces thromboembolic events after discharge. This study used a national, prospective, multicenter database to define the incidence of overall and postdischarge VTE after major vascular operations and assess risk factors associated with VTE development. METHODS: Patients with VTE who underwent elective vascular procedures (n = 45,548) were identified from the 2007-2009 National Surgical Quality Improvement Program (NSQIP) database. The vascular procedures included carotid endarterectomy (CEA; n = 20,785), open thoracoabdominal aortic aneurysm (TAAA) repair (n = 361), thoracic endovascular aortic repair (TEVAR; n = 732), open abdominal aortic (OAA) surgery (n = 6195), endovascular aneurysm repair (EVAR; n = 7361), and infrainguinal bypass graft (BPG; n = 10,114). Univariable and multivariable analyses were performed to ascertain risk factors associated with VTE. RESULTS: VTE was diagnosed in 187 patients (1.3 %) who underwent aortic surgery, with TAAA repair having the highest rate of VTE (4.2%), followed by TEVAR (2.2%), OAA surgery (1.7%), and EVAR (0.7%). In this subgroup, pulmonary embolisms (PE) were diagnosed in 52 (0.4%) and deep venous thrombosis (DVT) in 144 (1%). VTE rates were 1.0% and 0.2% for patients who underwent a BPG or CEA, respectively. Forty-one percent of all VTEs were diagnosed after discharge. The median (interquartile range) number of days from surgery to PE and DVT were 10 (5-15) and 10 (4-18), respectively. On multivariable analyses, type of surgical procedure, totally dependent functional status, disseminated cancer, postoperative organ space infection, postoperative cerebrovascular accident, failure to wean from ventilator ≤48 hours, and return to the operating room were significantly associated with development of VTE. In those experiencing a DVT or PE, overall mortality increased from 1.5% to 6.2% and from 1.5% to 5.7% respectively (P < .05 for both). CONCLUSIONS: Postoperative VTE is associated with the type of vascular procedure and is highest after operations in the chest and abdomen/pelvis. About 40% of VTE events in elective vascular surgery patients were diagnosed after discharge, and the presence of VTE was associated with a quadrupled mortality rate. Future studies should evaluate the benefit of DVT screening and postdischarge VTE prophylaxis in high-risk patients.


Asunto(s)
Hospitalización , Alta del Paciente , Procedimientos Quirúrgicos Vasculares/efectos adversos , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiología , Anciano , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Medición de Riesgo
13.
J Vasc Surg ; 58(4): 871-8, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23676190

RESUMEN

OBJECTIVE: Open infrarenal abdominal aortic aneurysm (oAAA) repair is associated with significant morbidity and mortality. Although there has been a shift toward endovascular repair, many patients continue to undergo an open repair due to anatomic considerations. Tools currently existing for estimation of periprocedural risk in patients undergoing open aortic surgery have certain limitations. The objective of this study was to develop a risk index to estimate the risk of 30-day perioperative mortality after elective oAAA repair. METHODS: Patients who underwent elective oAAA repair (n = 2845) were identified from the American College of Surgeons' 2007 to 2009 National Surgical Quality Improvement Program (NSQIP), a prospective database maintained at >250 centers. Univariable and multivariable analyses were performed to evaluate risk factors associated with 30-day mortality after oAAA repair and a risk index was developed. RESULTS: The 30-day mortality after oAAA repair was 3.3%. Multivariable analysis identified six preoperative predictors of mortality, and a risk index was created by assigning weighted points to each predictor using the ß-coefficients from the regression analysis. The predictors included dyspnea (at rest: 8 points; on moderate exertion: 2 points; none: 0 points), history of peripheral arterial disease requiring revascularization or amputation (3 points), age >65 years (3 points), preoperative creatinine >1.5 mg/dL (2 points), female gender (2 points), and platelets <150,000/mm(3) or >350,000/mm(3) (2 points). Patients were classified as low (<7%), intermediate (7%-15%), and high (>15%) risk for 30-day mortality based on a total point score of <8, 8 to 11, and >11, respectively. There were 2508 patients (88.2%) patients in the low-risk category, 278 (9.8%) in the intermediate-risk category, and 59 (2.1%) in the high-risk category. CONCLUSIONS: This risk index has excellent predictive ability for mortality after oAAA repair and awaits validation in subsequent studies. It is anticipated to aid patients and surgeons in informed patient consent, preoperative risk assessment, and optimization.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Técnicas de Apoyo para la Decisión , Procedimientos Quirúrgicos Vasculares/mortalidad , Anciano , Aneurisma de la Aorta Abdominal/mortalidad , Distribución de Chi-Cuadrado , Procedimientos Quirúrgicos Electivos , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos/epidemiología , Procedimientos Quirúrgicos Vasculares/efectos adversos
14.
Circulation ; 124(4): 381-7, 2011 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-21730309

RESUMEN

BACKGROUND: Perioperative myocardial infarction or cardiac arrest is associated with significant morbidity and mortality. The Revised Cardiac Risk Index is currently the most commonly used cardiac risk stratification tool; however, it has several limitations, one of which is its relatively low discriminative ability. The objective of the present study was to develop and validate a predictive cardiac risk calculator. METHODS AND RESULTS: Patients who underwent surgery were identified from the American College of Surgeons' 2007 National Surgical Quality Improvement Program database, a multicenter (>250 hospitals) prospective database. Of the 211 410 patients, 1371 (0.65%) developed perioperative myocardial infarction or cardiac arrest. On multivariate logistic regression analysis, 5 predictors of perioperative myocardial infarction or cardiac arrest were identified: type of surgery, dependent functional status, abnormal creatinine, American Society of Anesthesiologists' class, and increasing age. The risk model based on the 2007 data set was subsequently validated on the 2008 data set (n=257 385). The model performance was very similar between the 2007 and 2008 data sets, with C statistics (also known as area under the receiver operating characteristic curve) of 0.884 and 0.874, respectively. Application of the Revised Cardiac Risk Index to the 2008 National Surgical Quality Improvement Program data set yielded a relatively lower C statistic (0.747). The risk model was used to develop an interactive risk calculator. CONCLUSIONS: The cardiac risk calculator provides a risk estimate of perioperative myocardial infarction or cardiac arrest and is anticipated to simplify the informed consent process. Its predictive performance surpasses that of the Revised Cardiac Risk Index.


Asunto(s)
Algoritmos , Paro Cardíaco/diagnóstico , Modelos Cardiovasculares , Infarto del Miocardio/diagnóstico , Complicaciones Posoperatorias/diagnóstico , Procedimientos Quirúrgicos Operativos/efectos adversos , Adulto , Anciano , Femenino , Paro Cardíaco/etiología , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/etiología , Periodo Perioperatorio , Complicaciones Posoperatorias/etiología , Curva ROC , Medición de Riesgo/métodos
15.
J Vasc Surg ; 65(1): 261-262, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-28010864
16.
J Vasc Surg ; 55(3): 666-73, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22209613

RESUMEN

OBJECTIVE: The use of fenestrated and branched stent graft technology for paravisceral abdominal aortic aneurysms (PAAA) is on the rise; however, its application is limited in the United States to only a few selected centers. Most PAAAs are currently repaired using an open approach. The objective of this study was to determine which patients are at highest risk with open PAAA repair and might benefit most from endovascular repair using fenestrated or branched stent grafts. METHODS: This was a retrospective cohort study using data from American College of Surgeons National Surgical Quality Improvement Program (NSQIP) hospitals. We identified 598 patients (27.5% women) who underwent elective open PAAA repair from the 2007 to 2009 NSQIP, a prospective database maintained at >250 centers. The main outcome measure was 30-day postoperative mortality. RESULTS: The median patient age was 73 years. The 30-day major morbidity rate was 30.1%, and the mortality rate was 4.5%. Major complications included reintubation (10.0%), sepsis (10.7%), return to operating room (9.2%), new dialysis requirement (5.9%), cardiac arrest or myocardial infarction (4.5%), and stroke (1.2%). Multivariate analyses identified four predictors of postoperative mortality after open PAAA repair: peripheral arterial disease (PAD) requiring revascularization or amputation, chronic obstructive pulmonary disease (COPD), anesthesia time, and female sex. PAD and COPD were present in only 5.2% and 20.4% of patients but were associated with a 16.1% and 9.0% mortality rate, respectively. The mortality rate in women was 7.3% vs 3.5% for men (P = .045). CONCLUSIONS: PAD, COPD, and female sex are major risk factors for postoperative mortality after open PAAA repair. Fenestrated or branched stent graft repair may be a more valuable alternative to open repair for patients with one or more of these characteristics who have suitable access vessels.


Asunto(s)
Aneurisma de la Aorta Abdominal/mortalidad , Aneurisma de la Aorta Abdominal/cirugía , Implantación de Prótesis Vascular/mortalidad , Complicaciones Posoperatorias/mortalidad , Anciano , Anestesia/mortalidad , Distribución de Chi-Cuadrado , Bases de Datos Factuales , Procedimientos Quirúrgicos Electivos , Femenino , Mortalidad Hospitalaria , Humanos , Modelos Logísticos , Masculino , Análisis Multivariante , Selección de Paciente , Enfermedad Arterial Periférica/mortalidad , Enfermedad Arterial Periférica/cirugía , Complicaciones Posoperatorias/cirugía , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Reoperación , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores Sexuales , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos/epidemiología
17.
J Vasc Surg ; 56(2): 372-9, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22632800

RESUMEN

OBJECTIVE: For peripheral arterial disease, infrainguinal bypass grafting (BPG) carries a higher perioperative risk compared with peripheral endovascular procedures. The choice between the open and endovascular therapies is to an extent dependent on the expected periprocedural risk associated with each. Tools for estimating the periprocedural risk in patients undergoing BPG have not been reported in the literature. The objective of this study was to develop and validate a calculator to estimate the risk of perioperative mortality ≤30 days of elective BPG. METHODS: We identified 9556 patients (63.9% men) who underwent elective BPG from the 2007 to 2009 National Surgical Quality Improvement Program data sets. Multivariable logistic regression analysis was performed to identify risk factors associated with 30-day perioperative mortality. Bootstrapping was used for internal validation. The risk factors were subsequently used to develop a risk calculator. RESULTS: Patients had a median age of 68 years. The 30-day mortality rate was 1.8% (n = 170). Multivariable logistic regression analysis identified seven preoperative predictors of 30-day mortality: increasing age, systemic inflammatory response syndrome, chronic corticosteroid use, chronic obstructive pulmonary disease, dependent functional status, dialysis dependence, and lower extremity rest pain. Bootstrapping was used for internal validation. The model demonstrated excellent discrimination (C statistic, 0.81; bias-corrected C statistic, 0.81) and calibration. The validated risk model was used to develop an interactive risk calculator using the logistic regression equation. CONCLUSIONS: The validated risk calculator has excellent predictive ability for 30-day mortality in a patient after an elective BPG. It is anticipated to aid in surgical decision making, informed patient consent, preoperative optimization, and consequently, risk reduction.


Asunto(s)
Arteriopatías Oclusivas/mortalidad , Arteriopatías Oclusivas/cirugía , Conducto Inguinal/irrigación sanguínea , Modelos Estadísticos , Mortalidad Hospitalaria , Humanos , Modelos Logísticos , Análisis Multivariante , Medición de Riesgo
18.
J Surg Res ; 176(1): 329-36, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22099586

RESUMEN

BACKGROUND: The mechanical environment and properties of the carotid artery play an important role in the formation and progression of atherosclerosis in the carotid bifurcation. The purpose of this work was to measure and compare the range and variation of circumferential stress and tangent elastic moduli in the human common (CCA), external (ECA), and internal (ICA) carotid arteries over the cardiac cycle in vivo. METHODS: Measurements were performed in the surgically exposed proximal cervical CCA, distal ECA, and distal ICA of normotensive patients (n = 16) undergoing carotid endarterectomy. All measurements were completed in vivo over the cardiac cycle in the repaired carotid bifurcation after the atherosclerotic plaque was successfully removed. B-mode Duplex ultrasonography was used for measurement of arterial diameter and wall thickness, and an angiocatheter placed in the CCA was used for concurrent measurement of blood pressure. A semiautomatic segmentation algorithm was used to track changes in arterial diameter and wall thickness in response to blood pressure. These measurements were then used to calculate the variation of circumferential (hoop) stresses, tangent elastic moduli (the slope of the stress-strain curve at specified stresses), and strain-induced stiffness of the arterial wall (stiffening in response to the increase of intraluminal blood pressure) for each patient. RESULTS: The diameter and wall thickness of the segments (CCA, ECA, and ICA) of the carotid bifurcation were found to decrease and strain-induced stiffness to increase from proximal CCA to distal ECA and ICA. The circumferential stress from end-diastole (minimum pressure) to peak-systole (maximum pressure) varied nonlinearly from 25 ± 7 to 63 ± 23 kPa (CCA), from 22 ± 7 to 57 ± 19 kPa (ECA), and from 28 ± 8 to 67 ± 23 kPa (ICA). Tangent elastic moduli also varied nonlinearly from end-diastole to peak-systole as follows: from 0.40 ± 0.25 to 1.50 ± 2.05 MPa (CCA), from 0.49 ± 0.34 to 1.14 ± 0.52 MPa (ECA), and from 0.68 ± 0.31 to 1.51 ± 0.69 MPa (ICA). The strain-induced stiffness of CCA and ECA increased more than 3-fold and the stiffness of ICA increased more than 2.5-fold at peak-systole compared with end-diastole. CONCLUSIONS: The in vivo mechanical behavior of the three segments of the carotid bifurcation was qualitatively similar, but quantitatively different. All three arteries--CCA, ECA and ICA--exhibited nonlinear variations of circumferential stress and tangent elastic moduli within the normal pressure range. The variability in the properties of the three segments of the carotid bifurcation indicates a need for development of carotid models that match the in vivo properties of the carotid segments. Finally, the observed nonlinear behavior of the artery points to the need for future vascular mechanical studies to evaluate the mechanical factors of the arterial wall over the entire cardiac cycle.


Asunto(s)
Arteria Carótida Común/fisiología , Arteria Carótida Externa/fisiología , Arteria Carótida Interna/fisiología , Elasticidad/fisiología , Dinámicas no Lineales , Anciano , Fenómenos Biomecánicos , Presión Sanguínea/fisiología , Arteria Carótida Común/diagnóstico por imagen , Arteria Carótida Externa/diagnóstico por imagen , Arteria Carótida Interna/diagnóstico por imagen , Grosor Intima-Media Carotídeo , Endarterectomía Carotidea , Humanos , Masculino , Persona de Mediana Edad , Ultrasonografía Doppler Dúplex
19.
J Surg Res ; 167(2): 182-91, 2011 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-21109261

RESUMEN

BACKGROUND: The benefit of carotid endarterectomy (CEA) is heavily influenced by the risk of perioperative stroke. Our objective was to use the American College of Surgeons' 2007 and 2008 National Surgical Quality Improvement Program (NSQIP) database to assess the postoperative stroke and death rate after CEA among the more than 180 NSQIP participating hospitals, and to identify the preoperative risk factors. MATERIALS AND METHODS: Univariate analysis included 56 preoperative variables. Outcomes were studied for 30 d. Multivariate logistic regression was used for assessment of risk factors. RESULTS: Of 13,316 patients, 7503 (56.5%) were asymptomatic, while 5770 (43.5%) were symptomatic. Combined stroke or death was seen in 262 patients (2.0%). Postoperative stroke occurred in 186 patients (1.4%). One hundred patients (0.8%) died within 30 d. In asymptomatic and symptomatic patients, stroke or death was seen in 1.3% and 2.9% of patients; stroke in 0.9% and 2% of patients; and death in 0.5% and 1.1% of patients, respectively (all P < 0.001). On multivariate analysis for symptomatic patients, dialysis dependence, chronic open wound, impaired sensorium, and dependent functional status were risk factors for stroke or death (all P < 0.05). Among asymptomatic patients, acute renal failure, corticosteroid use, COPD, paraplegia, and dependent functional status were risk factors for stroke or death (all P < 0.05). CONCLUSIONS: This prospective database confirms that CEA is currently performed with low peri-procedural stroke rate in participating ACS NSQIP hospitals and provides a contemporary framework for comparison of other treatment modalities to CEA. Identification of the above risk factors may help with risk stratification and patient counseling for CEA.


Asunto(s)
Bases de Datos como Asunto , Endarterectomía Carotidea/efectos adversos , Periodo Perioperatorio , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/mortalidad , Anciano , Anciano de 80 o más Años , Enfermedades de las Arterias Carótidas/cirugía , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Prospectivos , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos
20.
J Vasc Surg ; 51(1): 80-8, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19837536

RESUMEN

OBJECTIVES: Symptomatic peripheral arterial disease (PAD) results in significant gait impairment. In an attempt to fully delineate and quantify these gait alterations, we analyzed joint kinematics, torques (rotational forces), and powers (rotational forces times angular velocity) in patients with PAD with unilateral claudication for both the affected and nonaffected legs. METHODS: Twelve patients with unilateral PAD (age, 61.69 +/- 10.53 years, ankle-brachial index [ABI]: affected limb 0.59 +/- 0.25; nonaffected limb 0.93 +/- 0.12) and 10 healthy controls (age, 67.23 +/- 12.67 years, ABI >1.0 all subjects) walked over a force platform to acquire gait kinetics, while joint kinematics were recorded simultaneously. Data were collected for the affected and nonaffected limbs during pain free (PAD-PF) and pain induced (PAD-P) trials. Kinetics and kinematics were combined to quantify torque and powers during the stance period from the hip, knee, and ankle joints. RESULTS: The affected limb demonstrated significantly (P <.05) reduced ankle plantar flexion torque compared to controls during late stance in both PAD-PF and PAD-P trials. There were significant reductions in ankle plantar flexion power generation during late stance for both the affected (P <.05) and nonaffected limbs (P <.05) compared to control during PAD-PF and PAD-P trials. No significant differences were noted in torque comparing the nonaffected limbs in PAD-PF and PAD-P conditions to control for knee and hip joints throughout the stance phase. Significant reductions were found in knee power absorption in early stance and knee power generation during mid stance for both limbs of the patients with PAD as compared to control (P <.05). CONCLUSION: Patients with PAD with unilateral claudication demonstrate significant gait impairments in both limbs that are present even before they experience any claudication symptoms. Overall, our data demonstrate significantly reduced ankle plantar flexion torque and power during late stance with reduced knee power during early and mid stance for the affected limb. Further studies are needed to determine if these findings are dependent on the location and the severity of lower extremity ischemia and whether the changes in the nonaffected limb are the result of underlying PAD or compensatory changes from the affected limb dysfunction.


Asunto(s)
Marcha , Claudicación Intermitente/fisiopatología , Articulaciones/fisiopatología , Extremidad Inferior/irrigación sanguínea , Fuerza Muscular , Músculo Esquelético/fisiopatología , Enfermedades Vasculares Periféricas/fisiopatología , Caminata , Adaptación Fisiológica , Anciano , Articulación del Tobillo/fisiopatología , Fenómenos Biomecánicos , Estudios de Casos y Controles , Prueba de Esfuerzo , Articulación de la Cadera/fisiopatología , Humanos , Claudicación Intermitente/etiología , Articulación de la Rodilla/fisiopatología , Masculino , Persona de Mediana Edad , Enfermedades Vasculares Periféricas/complicaciones , Rango del Movimiento Articular , Torque
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