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1.
J Pediatr Urol ; 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32698984

RESUMO

BACKGROUND: Surgical correction of undescended testes is a common surgical procedure which can be performed via a two-incision technique or a single high scrotal incision (Bianchi technique). The Bianchi technique requires less surgical time and may be associated with less pain in the initial postoperative period, however it has been adopted slowly due to a lack of familiarity and perceived technical challenges of the technique. Traditionally postoperative orchiopexy pain is managed with a caudal or ilioinguinal/iliohypogastric nerve block. As urologists at our site adopted the Bianchi technique, the anesthesiologists stopped performing caudals or ilioinguinal/iliohypogastric nerve blocks as local infiltration appeared sufficient. Therefore, this quality improvement (QI) project endeavoured to assess Alberta Children's Hospital's care pathway in its effectiveness to control pain in the first 24 h following pediatric orchiopexy using the Bianchi technique. METHODS: We completed a prospective QI project examining a care pathway for patients undergoing orchiopexy using the Bianchi technique. Eligible patients were healthy and aged 6 months to 12 years. A multimodal analgesic approach including local anesthetic surgical infiltration was used. Pain scores (FLACC) were recorded for up to 2 h postoperatively and a PPPM was completed at 24 h postoperatively. RESULTS: Sixty-four patients were included in the final analysis. The median discharge FLACC score was 0 (range 0-2) (Table 2). Median intraoperative morphine administered was 0.09 mg/kg with no significant correlations between the amount of morphine administered and postoperative pain measures. Median PPPM scores were 4 and 3.5 for unilateral and bilateral procedures, respectively. CONCLUSIONS: We have demonstrated that orchiopexies repaired using the Bianchi technique following the care pathway established at Alberta Children's Hospital are associated with minimal pain scores. Our QI project suggests that combining a Bianchi technique with a simple multimodal analgesic approach including local infiltration, negates the need for regional anesthesia techniques, yet still provides adequate analgesia.

3.
Circ Heart Fail ; 13(5): e006746, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32354281

RESUMO

BACKGROUND: Hospitalization is a common adverse event in people with heart failure and reduced ejection fraction, yet is often not primarily due to decompensated heart failure (HF). We investigated the long-term prognosis following infection-related hospitalization. METHODS: We conducted a prospective observational cohort study of 711 people with heart failure and reduced ejection fraction recruited from 4 specialist HF clinics in the United Kingdom. All hospitalization episodes (n=1568) were recorded and categorized as primarily due to decompensated HF, other cardiovascular disease, infection-related, or other noncardiovascular disease. Survival was determined after the first hospitalization. RESULTS: During 2900 patient-years of follow-up, there were a total of 14 686 hospital days. At least one hospitalization occurred in 467 people (66%); 25% of first hospitalizations were primarily due to infection and these were not associated with typical signs including tachycardia and pyrexia. Compared with other categories of hospitalization, infection-related was associated with older age, lower serum albumin, higher blood neutrophil counts, and greater prevalence of chronic obstructive pulmonary disease at recruitment. Median survival after first infection-related hospitalization was 18.6 months, comparable to that after first decompensated HF hospitalization, even after age-sex adjustment. The burden of all-cause rehospitalization was comparable irrespective of the category of first hospitalization, but infection more commonly caused re-hospitalization after index infection hospitalization. CONCLUSIONS: Infection is a common driver of hospitalization in heart failure and reduced ejection fraction and often presents without classical signs. It is associated with high mortality rates, comparable to decompensated HF, and a major burden of rehospitalization caused by recurrent episodes of infection.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31811299

RESUMO

BACKGROUND: Determining an optimal location within the right atrium (RA) for placement of the distal ventriculoatrial (VA) shunt catheter offer several operative challenges that place patients at risk for perioperative complications and downstream VA shunt failure. Utilizing transesophageal echocardiography (TEE) guidance to place distal VA shunt catheters may help to circumvent these risks. OBJECTIVE: To review our current practice of VA shunt insertion using TEE guidance. METHODS: A retrospective review of all consecutive patients who underwent VA shunt procedures between December 19, 2016 and January 22, 2019, during which time intraoperative TEE was used for shunt placement was performed. Data on the time required for shunt placement and total procedure time, baseline echocardiography findings, and short- and long-term complications of shunt placement were assessed. RESULTS: A total of 33 patients underwent VA shunt procedures, with a median follow-up time of 250 (88-412) d. The only immediate complication related to shunt placement or TEE use was transient ectopy in 1 patient. The mean time for atrial catheter insertion was 12.6 ± 4.8 min. Right-heart catheters were inserted between the RA-superior vena cava junction and 22 mm within the RA in all but 3 procedures. A total of 7/33 patients (21%) underwent shunt revision. Indications for revisions included distal clots, proximal obstruction, positive blood culture, and shunt valve revision. No other complications of VA shunt insertion were reported. CONCLUSION: VA shunt insertion using TEE allows for precise distal catheter placement. Early patient experience confirms this technique has a low complication rate.

5.
J Am Heart Assoc ; 7(20): e009684, 2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30371261

RESUMO

Background Noncardiovascular death is increasingly common in people with chronic heart failure ( CHF ), yet its causes remain poorly characterized. We aimed to define the prevalence of sepsis death in people with CHF and to ascertain its risk marker profile. Methods and Results We conducted a prospective cohort study of 1802 patients with CHF and left ventricular ejection fraction ≤45% attending CHF clinics in 4 United Kingdom hospitals between 2006 and 2014. Mode of death was defined over a 10.3-year follow-up period (mean 4 years). Competing risk regression defined mode-specific hazard ratios for sepsis, other noncardiovascular, progressive heart failure, and sudden cardiac death in relation to established heart failure prognostic markers. Of 737 deaths, 173 (23.5%) were due to sepsis; respiratory tract infections accounted for 69.9% (n=121) of these events. Those who died from sepsis were older, had higher platelet counts, and had a higher prevalence of chronic obstructive pulmonary disease than those who died from other causes. Sepsis death was independently associated with older age (hazard ratio=1.05; 95% confidence interval 1.03-1.07), greater prevalence of chronic obstructive pulmonary disease (2.43; 1.74-3.40), male sex (1.73; 1.16-2.60), lower log serum vitamin D (0.68; 0.49-0.95), and higher platelet count (1.002; 1.000-1.005) than nonsepsis death. Established heart failure prognostic markers exhibited different patterns of association with sepsis death, other noncardiovascular death, progressive heart failure death, and sudden cardiac death. Conclusions Sepsis is a major contributor to death in people with CHF and has a different risk marker profile from other modes of death, suggesting that it may be amenable to targeted preventative strategies.


Assuntos
Insuficiência Cardíaca/mortalidade , Sepse/mortalidade , Disfunção Ventricular Esquerda/mortalidade , Fatores Etários , Idoso , Doença Crônica , Morte Súbita Cardíaca/epidemiologia , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Prevalência , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/mortalidade , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Sepse/fisiopatologia , Fatores Sexuais , Volume Sistólico/fisiologia , Reino Unido/epidemiologia , Disfunção Ventricular Esquerda/fisiopatologia
6.
J Am Heart Assoc ; 7(20): e009770, 2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30371286

RESUMO

Background The CASTLE - AF (Catheter Ablation versus Standard Conventional Therapy in Patients With Left Ventricular Dysfunction and Atrial Fibrillation) trial recently reported that catheter ablation of atrial fibrillation ( AF ) improves survival in heart failure (HF) with reduced ejection fraction ( HF r EF ). However, established AF was not associated with mortality in trials of contemporary HF r EF pharmacotherapies. We investigated whether HF r EF pathogenesis may influence the conclusions of studies evaluating the prognostic impact of AF . Methods and Results Using a prospective cohort study of 791 patients with HFr EF , with AF determined using 24-hour ambulatory ECG monitoring, univariable and multivariable Cox regression analyses were used to define the association between AF and mode-specific mortality (mean follow-up of 5.4 years). One-year HF-related hospitalization was assessed with binary logistic regression analysis. One-year cardiac remodeling was assessed in a subgroup (n=378) using echocardiography. AF was present in 28.2% of patients, with 9.4% of these being paroxysmal. While AF was associated with increased risk of all-cause mortality (hazard ratio, 1.27; 95% confidence interval 1.03-1.57), with diverging survival curves after 1 year of follow-up, this association was lost in age-sex-adjusted analyses. However, AF was associated with increased risk of age-sex-adjusted all-cause mortality in people with ischemic pathogenesis, with a statistically significant interaction between pathogenesis and AF. This was predominantly attributed to progressive HF deaths. After 1 year, HF hospitalization and cardiac remodeling were not associated with AF , even in people with ischemic pathogenesis. Conclusions AF is associated with increased risk of death in HF r EF of ischemic pathogenesis, predominantly due to progressive HF deaths during long-term follow-up. HF r EF pathogenesis should be considered in trial design and interpretation.


Assuntos
Fibrilação Atrial/complicações , Insuficiência Cardíaca/complicações , Isquemia Miocárdica/complicações , Idoso , Fibrilação Atrial/mortalidade , Causas de Morte , Angiopatias Diabéticas/complicações , Angiopatias Diabéticas/mortalidade , Angiopatias Diabéticas/fisiopatologia , Progressão da Doença , Eletrocardiografia Ambulatorial , Feminino , Insuficiência Cardíaca/mortalidade , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Isquemia Miocárdica/mortalidade , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/mortalidade , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Volume Sistólico/fisiologia , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/mortalidade , Remodelação Ventricular/fisiologia
7.
Endocrinology ; 159(8): 2917-2925, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29796592

RESUMO

Reduced systemic insulin signaling promotes endothelial dysfunction and diminished endogenous vascular repair. We investigated whether restoration of endothelial insulin receptor expression could rescue this phenotype. Insulin receptor knockout (IRKO) mice were crossed with mice expressing a human insulin receptor endothelial cell-specific overexpression (hIRECO) to produce IRKO-hIRECO progeny. No metabolic differences were noted between IRKO and IRKO-hIRECO mice in glucose and insulin tolerance tests. In contrast with control IRKO littermates, IRKO-hIRECO mice exhibited normal blood pressure and aortic vasodilatation in response to acetylcholine, comparable to parameters noted in wild type littermates. These phenotypic changes were associated with increased basal- and insulin-stimulated nitric oxide production. IRKO-hIRECO mice also demonstrated normalized endothelial repair after denuding arterial injury, which was associated with rescued endothelial cell migration in vitro but not with changes in circulating progenitor populations or culture-derived myeloid angiogenic cells. These data show that restoration of endothelial insulin receptor expression alone is sufficient to prevent the vascular dysfunction caused by systemically reduced insulin signaling.


Assuntos
Aorta/metabolismo , Glicemia/metabolismo , Endotélio Vascular/metabolismo , Haploinsuficiência/genética , Receptor de Insulina/genética , Vasodilatação/genética , Acetilcolina/farmacologia , Animais , Antígenos CD/genética , Aorta/fisiopatologia , Pressão Sanguínea , Movimento Celular , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Teste de Tolerância a Glucose , Humanos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Óxido Nítrico/metabolismo , Receptor de Insulina/metabolismo , Transdução de Sinais , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia
8.
Heart ; 104(12): 993-998, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29386325

RESUMO

OBJECTIVE: To characterise the association between socioeconomic deprivation and adverse outcomes in patients with chronic heart failure (CHF). METHODS: We prospectively observed 1802 patients with CHF and left ventricular ejection fraction (LVEF) ≤45%, recruited in four UK hospitals between 2006 and 2014. We assessed the association between deprivation defined by the UK Index of Multiple Deprivation (IMD) and: mode-specific mortality (mean follow-up 4 years); mode-specific hospitalisation; and the cumulative duration of hospitalisation (after 1 year). RESULTS: A 45-point difference in mean IMD score was noted between patients residing in the least and most deprived quintiles of geographical regions. Deprivation was associated with age, sex and comorbidity, but not CHF symptoms, LVEF or prescribed drug therapy. IMD score was associated with the risk of age-sex adjusted all-cause mortality (6% higher risk per 10-unit increase in IMD score; 95% CI 2% to 10%; P=0.004), and non-cardiovascular mortality (9% higher risk per 10-unit increase in IMD score; 95% CI 3% to 16%; P=0.003), but not cardiovascular mortality. All-cause, but not heart failure-specific, hospitalisation was also more common in the most deprived patients. Overall, patients spent a cumulative 3.3 days in hospital during 1 year of follow-up, with IMD score being associated with the age-sex adjusted cumulative duration of hospitalisations (4% increase in duration per 10-unit increase in IMD score; 95% CI 3% to 6%; P<0.0005). CONCLUSIONS: Socioeconomic deprivation in people with CHF is linked to increased risk of death and hospitalisation due to an excess of non-cardiovascular events.


Assuntos
Insuficiência Cardíaca/mortalidade , Determinantes Sociais da Saúde , Fatores Socioeconômicos , Disfunção Ventricular Esquerda/mortalidade , Idoso , Doença Crônica , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Hospitalização , Humanos , Masculino , Pobreza , Prognóstico , Estudos Prospectivos , Fatores de Risco , Volume Sistólico , Fatores de Tempo , Reino Unido/epidemiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/terapia , Função Ventricular Esquerda
9.
Diabetes Care ; 41(1): 136-142, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28982651

RESUMO

OBJECTIVE: Diabetes increases mortality in patients with chronic heart failure (CHF) and reduced left ventricular ejection fraction. Studies have questioned the safety of ß-adrenoceptor blockers (ß-blockers) in some patients with diabetes and reduced left ventricular ejection fraction. We examined whether ß-blockers and ACE inhibitors (ACEIs) are associated with differential effects on mortality in CHF patients with and without diabetes. RESEARCH DESIGN AND METHODS: We conducted a prospective cohort study of 1,797 patients with CHF recruited between 2006 and 2014, with mean follow-up of 4 years. ß-Blocker dose was expressed as the equivalent dose of bisoprolol (mg/day) and ACEI dose as the equivalent dose of ramipril (mg/day). Cox regression analysis was used to examine the interaction between diabetes and drug dose on all-cause mortality. RESULTS: Patients with diabetes were prescribed larger doses of ß-blockers and ACEIs than were patients without diabetes. Increasing ß-blocker dose was associated with lower mortality in patients with diabetes (8.9% per mg/day; 95% CI 5-12.6) and without diabetes (3.5% per mg/day; 95% CI 0.7-6.3), although the effect was larger in people with diabetes (interaction P = 0.027). Increasing ACEI dose was associated with lower mortality in patients with diabetes (5.9% per mg/day; 95% CI 2.5-9.2) and without diabetes (5.1% per mg/day; 95% CI 2.6-7.6), with similar effect size in these groups (interaction P = 0.76). CONCLUSIONS: Increasing ß-blocker dose is associated with a greater prognostic advantage in CHF patients with diabetes than in CHF patients without diabetes.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Diabetes Mellitus/mortalidade , Insuficiência Cardíaca/mortalidade , Idoso , Biomarcadores/sangue , Doença Crônica , Diabetes Mellitus/tratamento farmacológico , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Masculino , Prognóstico , Estudos Prospectivos , Função Ventricular Esquerda/efeitos dos fármacos
10.
Diabetes ; 66(11): 2808-2821, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28830894

RESUMO

Shc homology 2-containing inositol 5' phosphatase-2 (SHIP2) is a lipid phosphatase that inhibits insulin signaling downstream of phosphatidylinositol 3-kinase (PI3K); its role in vascular function is poorly understood. To examine its role in endothelial cell (EC) biology, we generated mice with catalytic inactivation of one SHIP2 allele selectively in ECs (ECSHIP2Δ/+). Hyperinsulinemic-euglycemic clamping studies revealed that ECSHIP2Δ/+ was resistant to insulin-stimulated glucose uptake in adipose tissue and skeletal muscle compared with littermate controls. ECs from ECSHIP2Δ/+ mice had increased basal expression and activation of PI3K downstream targets, including Akt and endothelial nitric oxide synthase, although incremental activation by insulin and shear stress was impaired. Insulin-mediated vasodilation was blunted in ECSHIP2Δ/+ mice, as was aortic nitric oxide bioavailability. Acetylcholine-induced vasodilation was also impaired in ECSHIP2Δ/+ mice, which was exaggerated in the presence of a superoxide dismutase/catalase mimetic. Superoxide abundance was elevated in ECSHIP2Δ/+ ECs and was suppressed by PI3K and NADPH oxidase 2 inhibitors. These findings were phenocopied in healthy human ECs after SHIP2 silencing. Our data suggest that endothelial SHIP2 is required to maintain normal systemic glucose homeostasis and prevent oxidative stress-induced endothelial dysfunction.


Assuntos
Endotélio Vascular/metabolismo , Resistência à Insulina/fisiologia , NADPH Oxidase 2/metabolismo , Estresse Oxidativo/fisiologia , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/metabolismo , Animais , Aorta , Células Cultivadas , Células Endoteliais , Regulação da Expressão Gênica/fisiologia , Técnica Clamp de Glucose , Intolerância à Glucose , Camundongos , Camundongos Knockout , NADPH Oxidase 2/genética , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/genética , Vasoconstrição/fisiologia
11.
Anesthesiology ; 126(4): 653-665, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28182585

RESUMO

BACKGROUND: Patients undergoing endovascular therapy for acute ischemic stroke may require general anesthesia to undergo the procedure. At present, there is little clinical evidence to guide the choice of anesthetic in this acute setting. The clinical implications of experimental studies demonstrating anesthetic neuroprotection are poorly understood. Here, the authors evaluated the impact of anesthetic treatment on neurologic outcome in experimental stroke. METHODS: Controlled studies of anesthetics in stroke using the filament occlusion model were identified in electronic databases up to December 15, 2015. The primary outcome measures, infarct volume, and neurologic deficit score were used to calculate the normalized mean difference for each comparison. Meta-analysis of normalized mean difference values provided estimates of neuroprotection and contributions of predefined factors: study quality, the timing of treatment, and the duration of ischemia. RESULTS: In 80 retrieved publications anesthetic treatment reduced neurologic injury by 28% (95% CI, 24 to 32%; P < 0.0001). Internal validity was high: publication bias enhanced the effect size by 4% or less, effect size increased with study quality (P = 0.0004), and approximately 70% of studies were adequately powered. Apart from study quality, no predefined factor influenced neuroprotection. Neuroprotection failed in animals with comorbidities. Neuroprotection by anesthetics was associated with prosurvival mechanisms. CONCLUSIONS: Anesthetic neuroprotection is a robust finding in studies using the filament occlusion model of ischemic stroke and should be assumed to influence outcomes in studies using this model. Neuroprotection failed in female animals and animals with comorbidities, suggesting that the results in young male animals may not reflect human stroke.


Assuntos
Anestésicos/farmacologia , Neuroproteção/efeitos dos fármacos , Acidente Vascular Cerebral/prevenção & controle , Animais , Modelos Animais de Doenças , Camundongos , Ratos
12.
Circ Res ; 120(5): 784-798, 2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-27920123

RESUMO

RATIONALE: In the endothelium, insulin stimulates endothelial NO synthase (eNOS) to generate the antiatherosclerotic signaling radical NO. Insulin-resistant type 2 diabetes mellitus is associated with reduced NO availability and accelerated atherosclerosis. The effect of enhancing endothelial insulin sensitivity on NO availability is unclear. OBJECTIVE: To answer this question, we generated a mouse with endothelial cell (EC)-specific overexpression of the human insulin receptor (hIRECO) using the Tie2 promoter-enhancer. METHODS AND RESULTS: hIRECO demonstrated significant endothelial dysfunction measured by blunted endothelium-dependent vasorelaxation to acetylcholine, which was normalized by a specific Nox2 NADPH oxidase inhibitor. Insulin-stimulated phosphorylation of protein kinase B was increased in hIRECO EC as was Nox2 NADPH oxidase-dependent generation of superoxide, whereas insulin-stimulated and shear stress-stimulated eNOS activations were blunted. Phosphorylation at the inhibitory residue Y657 of eNOS and expression of proline-rich tyrosine kinase 2 that phosphorylates this residue were significantly higher in hIRECO EC. Inhibition of proline-rich tyrosine kinase 2 improved insulin-induced and shear stress-induced eNOS activation in hIRECO EC. CONCLUSIONS: Enhancing insulin sensitivity specifically in EC leads to a paradoxical decline in endothelial function, mediated by increased tyrosine phosphorylation of eNOS and excess Nox2-derived superoxide. Increased EC insulin sensitivity leads to a proatherosclerotic imbalance between NO and superoxide. Inhibition of proline-rich tyrosine kinase 2 restores insulin-induced and shear stress-induced NO production. This study demonstrates for the first time that increased endothelial insulin sensitivity leads to a proatherosclerotic imbalance between NO and superoxide.


Assuntos
Aterosclerose/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Resistência à Insulina/fisiologia , Transdução de Sinais/fisiologia , Animais , Aterosclerose/patologia , Células Cultivadas , Células Endoteliais/patologia , Endotélio Vascular/patologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Técnicas de Cultura de Órgãos
13.
Can Respir J ; 2016: 6803860, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27445560

RESUMO

Objective. There is increasing evidence of adverse outcomes associated with blood transfusions for adult traumatic brain injury patients. However, current evidence suggests that pediatric traumatic brain injury patients may respond to blood transfusions differently on a vascular level. This study examined the influence of blood transfusions and anemia on the outcome of pediatric traumatic brain injury patients. Design. A retrospective cohort analysis of severe pediatric traumatic brain injury (TBI) patients was undertaken to investigate the association between blood transfusions and anemia on patient outcomes. Measurements and Main Results. One hundred and twenty patients with severe traumatic brain injury were identified and included in the analysis. The median Glasgow Coma Scale (GCS) was 6 and the mean hemoglobin (Hgb) on admission was 115.8 g/L. Forty-three percent of patients (43%) received at least one blood transfusion and the mean hemoglobin before transfusion was 80.1 g/L. Multivariable regression analysis revealed that anemia and the administration of packed red blood cells were not associated with adverse outcomes. Factors that were significantly associated with mortality were presence of abusive head trauma, increasing PRISM score, and low GCS after admission. Conclusion. In this single centre retrospective cohort study, there was no association found between anemia, blood transfusions, and hospital mortality in a pediatric traumatic brain injury patient population.


Assuntos
Anemia/terapia , Lesões Encefálicas Traumáticas/mortalidade , Transfusão de Eritrócitos , Hemoglobinas/metabolismo , Mortalidade Hospitalar , Adolescente , Anemia/complicações , Anemia/metabolismo , Transfusão de Sangue , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/metabolismo , Criança , Maus-Tratos Infantis/estatística & dados numéricos , Pré-Escolar , Estudos de Coortes , Bases de Dados Factuais , Feminino , Escala de Coma de Glasgow , Humanos , Lactente , Masculino , Análise Multivariada , Análise de Regressão , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença
14.
Sci Rep ; 6: 29981, 2016 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-27436676

RESUMO

It is widely accepted that water-rich serpentinite domains are commonly present in the mantle above shallow subducting slabs and play key roles in controlling the geochemical cycling and physical properties of subduction zones. Thermal and petrological models show the dominant serpentine mineral is antigorite. However, there is no good consensus on the amount, distribution and alignment of this mineral. Seismic velocities are commonly used to identify antigorite-rich domains, but antigorite is highly-anisotropic and depending on the seismic ray path, its properties can be very difficult to distinguish from non-hydrated olivine-rich mantle. Here, we utilize this anisotropy and show how an analysis of seismic anisotropy that incorporates measured ray path geometries in the Ryukyu arc can constrain the distribution, orientation and amount of antigorite. We find more than 54% of the wedge must consist of antigorite and the alignment must change from vertically aligned to parallel to the slab. This orientation change suggests convective flow in the hydrated forearc mantle. Shear wave splitting analysis in other subduction zones indicates large-scale serpentinization and forearc mantle convection are likely to be more widespread than generally recognized. The view that the forearc mantle of cold subduction zones is dry needs to be reassessed.

16.
Heart ; 102(3): 223-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26674986

RESUMO

OBJECTIVE: We aimed to define the prognostic value of the heart rate range during a 24 h period in patients with chronic heart failure (CHF). METHODS: Prospective observational cohort study of 791 patients with CHF associated with left ventricular systolic dysfunction. Mode-specific mortality and hospitalisation were linked with ambulatory heart rate range (AHRR; calculated as maximum minus minimum heart rate using 24 h Holter monitor data, including paced and non-sinus complexes) in univariate and multivariate analyses. Findings were then corroborated in a validation cohort of 408 patients with CHF with preserved or reduced left ventricular ejection fraction. RESULTS: After a mean 4.1 years of follow-up, increasing AHRR was associated with reduced risk of all-cause, sudden, non-cardiovascular and progressive heart failure death in univariate analyses. After accounting for characteristics that differed between groups above and below median AHRR using multivariate analysis, AHRR remained strongly associated with all-cause mortality (HR 0.991/bpm increase in AHRR (95% CI 0.999 to 0.982); p=0.046). AHRR was not associated with the risk of any non-elective hospitalisation, but was associated with heart-failure-related hospitalisation. AHRR was modestly associated with the SD of normal-to-normal beats (R(2)=0.2; p<0.001) and with peak exercise-test heart rate (R(2)=0.33; p<0.001). Analysis of the validation cohort revealed AHRR to be associated with all-cause and mode-specific death as described in the derivation cohort. CONCLUSIONS: AHRR is a novel and readily available prognosticator in patients with CHF, which may reflect autonomic tone and exercise capacity.


Assuntos
Eletrocardiografia Ambulatorial , Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca , Disfunção Ventricular Esquerda/fisiopatologia , Idoso , Doença Crônica , Estudos de Coortes , Teste de Esforço , Feminino , Insuficiência Cardíaca/mortalidade , Hospitalização/estatística & dados numéricos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Estudos Prospectivos , Disfunção Ventricular Esquerda/mortalidade
17.
Paediatr Anaesth ; 25(3): 301-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25495405

RESUMO

BACKGROUND: Aspiration of gastric contents can be a serious anesthetic-related complication. Gastric antral sonography prior to anesthesia may have a role in identifying pediatric patients at risk of aspiration. We examined the relationship between sonographic antral area and endoscopically suctioned gastric volumes, and whether a 3-point qualitative grading system is applicable in pediatric patients. METHODS: Fasted patients presenting to a pediatric hospital for upper gastrointestinal endoscopy were included in the study. Sonographic measurement of the antral cross-sectional area (CSA) in supine (supine CSA) and right lateral decubitus (RLD CSA) position was completed, and the antrum was designated as empty or nonempty. Gastric contents were endoscopically suctioned and measured. Multiple regression analysis was used to fit a mathematical model to estimate gastric volume. RESULTS: One hundred patients (aged 11-216 months) were included. The gastric antrum was measured in 94% and 99% of patients in the supine and RLD positions, respectively. Gastric antral CSA correlated with total gastric volume in both supine (ρ = 0.63) and RLD (ρ = 0.67) positions. A mathematical model incorporating RLD CSA and age (R(2)  = 0.60) was determined as the best-fit model to predict gastric volumes. Increasing gastric antral grade (0-2) was associated with increasing gastric fluid volume. CONCLUSION: The results suggest that sonographic assessment of the gastric antrum provides useful information regarding gastric content (empty versus nonempty) and volume (ml·kg(-1) ) in pediatric patients. Results suggest that the three-point grading system may be a valuable tool to assess gastric 'fullness' based on a qualitative exam of the antrum.


Assuntos
Endoscopia Gastrointestinal/métodos , Jejum/fisiologia , Estômago/diagnóstico por imagem , Sucção/métodos , Adolescente , Algoritmos , Anatomia Transversal , Anestesia Geral , Criança , Pré-Escolar , Feminino , Esvaziamento Gástrico , Conteúdo Gastrointestinal , Humanos , Lactente , Masculino , Modelos Estatísticos , Valor Preditivo dos Testes , Antro Pilórico/diagnóstico por imagem , Aspiração Respiratória de Conteúdos Gástricos/prevenção & controle , Medição de Risco , Ultrassonografia
18.
Plant Cell Environ ; 38(8): 1503-13, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25495925

RESUMO

Drought induces xylem embolism formation, but grapevines can refill non-functional vessels to restore transport capacity. It is unknown whether vulnerability to embolism formation and ability to repair differ among grapevine species. We analysed in vivo embolism formation and repair using x-ray computed microtomography in three wild grapevine species from varied native habitats (Vitis riparia, V. arizonica, V. champinii) and related responses to measurements of leaf gas exchange and root pressure. Vulnerability to embolism formation was greatest in V. riparia, intermediate in V. arizonica and lowest in V. champinii. After re-watering, embolism repair was rapid and pronounced in V. riparia and V. arizonica, but limited or negligible in V. champinii even after numerous days. Similarly, root pressure measured after re-watering was positively correlated with drought stress severity for V. riparia and V. arizonica (species exhibiting embolism repair) but not for V. champinii. Drought-induced reductions in transpiration were greatest for V. riparia and least in V. champinii. Recovery of transpiration after re-watering was delayed for all species, but was greatest for V. champinii and most rapid in V. arizonica. These species exhibit varied responses to drought stress that involve maintenance/recovery of xylem transport capacity coordinated with root pressure and gas exchange responses.


Assuntos
Ecossistema , Gases/metabolismo , Folhas de Planta/fisiologia , Raízes de Plantas/fisiologia , Pressão , Vitis/fisiologia , Caules de Planta/fisiologia , Transpiração Vegetal/fisiologia , Fatores de Tempo , Água , Microtomografia por Raio-X
20.
Biorheology ; 51(4-5): 275-91, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25281596

RESUMO

BACKGROUND: Although a blood analog of aqueous glycerol and xanthan gum was found to replicate the viscoelastic behavior of blood, measurements were restricted to laminar flow. OBJECTIVE: To expand the characterization of a non-Newtonian blood analog of aqueous glycerol and xanthan gum to transitional Reynolds numbers to quantify its behavior as a function of both natural and shear-layer-induced mechanisms. METHODS: A Newtonian analog and a shear-thinning aqueous glycerol, xanthan gum solution were circulated through an in vitro flow loop replicating both a straight and obstructed artery where transition was initiated through natural and shear-layer-induced mechanisms respectively. Steady and pulsatile pressure drop measurements for both fluids were acquired across a range of Reynolds numbers up to 7600 and Womersley numbers of 4 and 6. RESULTS: In steady and pulsatile straight flow, the non-Newtonian analog presented with reduced pressure drops and prolonged laminar flow to Reynolds numbers of 3200 and 3800 respectively. Upon blockage inclusion, non-Newtonian minor losses were comparable to Newtonian in steady flow and greater in pulsatile flow suggesting an elongation of downstream non-Newtonian recirculation. Although non-Newtonian total system pressure drops in both straight and obstructed flows were lower, the ratio of pressure drop difference between the two fluids decreased through shear-layer-induced transition. CONCLUSIONS: These findings not only demonstrated the suitability of using a xanthan gum analog to model blood flow in transitional regimes, but also presented the respective differences in analog behavior as a function of transition mechanism.


Assuntos
Velocidade do Fluxo Sanguíneo , Fluxo Pulsátil/fisiologia , Viscosidade Sanguínea , Elasticidade , Glicerol/química , Humanos , Modelos Cardiovasculares , Polissacarídeos Bacterianos/química , Reologia/métodos , Estresse Mecânico , Viscosidade
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