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Background: Although palliative medicine (PM) is more commonly being integrated into the intensive care unit (ICU), research on racial disparities in this area is lacking. Our objectives were to (a) identify racial disparities in utilization of PM consultation for patients who received ICU care and (b) determine if there were differences in the use of code status or PM consultation over time based on race. Materials and Methods: Retrospective analysis of 571 patients, 18 years and above, at a tertiary care institution who received ICU care and died during their hospital stay. We analyzed two timeframes, 2008-2009 and 2018-2019. Univariate analysis was utilized to evaluate baseline characteristics. A multivariate logistic regression model and interaction P values were employed to assess for differential use of PM consultation, do not resuscitate (DNR) orders, and comfort care (CC) orders between races in aggregate and for changes over time. Results: There was a notable increase in Black/African-American (AA) (54% to 61%) and Hispanic/Latino (2% to 3%) patients over time in our population. Compared to White patients, we found no differences between PM consultation and CC orders. There was a lower probability of DNR orders for Black/AA (adjusted odds ratio [aOR] 0.569; P = .049; confidence interval [CI]: 0.324-0.997) and other/unknown/multiracial patients (aOR: 0.389; P = .273; CI: 0.169-0.900). Comparing our earlier time period to the later time period, we found an increased usage of PM for all patients. Interaction P values suggest there were no differences between races regarding PM, DNR, and CC orders. Conclusions: PM use has increased over time at our institution. Contrary to the previous literature, there were no differences in the frequency of utilization of PM consultation between races. Further analysis to evaluate the usage of PM in the ICU setting in varying populations and geographic locations is warranted.
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Cuidados Paliativos na Terminalidade da Vida , Medicina Paliativa , Assistência Terminal , Humanos , Estudos Retrospectivos , Cuidados Paliativos , Ordens quanto à Conduta (Ética Médica) , Unidades de Terapia IntensivaRESUMO
PURPOSE: Instructional videos of medical procedures can be a useful guide for learners, demonstrating proper and safe technique. Open publishing sites such as YouTube are readily accessible, however the content is not peer reviewed and quality of videos vary greatly. Our aim was to evaluate a learner's ability to interpret the quality of openly published content by comparing their rating of the most popular central line insertion videos on YouTube to expert evaluations. METHOD: YouTube search results for "central line placement" sorted by views or relevance compiled a list of the four most common videos. A fifth gold standard video, published by the New England Journal, was included, however was not found in the top results. Eleven expert practitioners from varying medical specialties (Critical Care, Surgery, Anesthesia, & Emergency Medicine) evaluated the 5 videos, utilizing a 22-item Likert scaled questionnaire emphasizing: preparation, sterility, anatomy, technique, & complications. Videos were compared as a composite average of the individual items on the survey. The highest, lowest, and 3rd ranked videos were evaluated by 45 residents ("learners") in varying specialties (Internal Medicine, Emergency Medicine, Surgery, Anesthesia) and post graduate year (PGY). Learners assessed the videos using the same scale. A Welch T-test assessed statistical significance between the two groups. Subgroup analysis compared experts against different PGY and specialty cohorts. RESULTS: The lowest scored video among the experts and learners was the most popular on YouTube, with 858,933 views at the time of inclusion. Though lowest in rank, this video was judged higher by learners than the experts (2.63/5 vs 2.18/5, P = 0.0029). The 3rd ranked video by experts with 249,746 views on YouTube, was also rated higher by learners (3.77/5 vs 3.45/5, P = 0.0084). The gold standard video by NEJM had 320,580 views and was rated highest by both the experts and learners (4.37/5 vs 4.28/5, P = 0.518). Subgroup analysis showed similar results with learners rating the videos overall better than experts, this was particularly true in the PGY-1 subgroup. CONCLUSION: The most popular central line insertion video was the worst rated by both experts and learners. Learners rated all the videos better than the expert. YouTube videos demonstrating medical procedures including central line insertion should come from peer reviewed sources if they are to be incorporated into educational curriculum.
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Mídias Sociais , Humanos , Procedimentos Cirúrgicos Vasculares , Gravação em VídeoRESUMO
INTRODUCTION: Ventilator associated pneumonia (VAP) rate has been tracked as a comparable quality measure but there is significant variation between types of ICUs. We sought to understand variability and improve its utility as a marker of quality. METHODS: The National Trauma Database was surveyed to identify risk factors for VAP. Logistic regression, χ2, Student's T-test or Mann-Whitney U test were used. RESULTS: Risk factors associated with developing VAP were: injury severity score (ISS) (OR 1.03, 95% CI 1.03 -1.04), prehospital assisted respiration (PHAR) (OR 1.10, 1.03 -1.17), thoracic injuries (OR 2.28, 1.69-3.08), diabetes (OR 1.32, 1.20 -1.46), male gender (OR 1.38, 1.28 -1.60), care at a teaching hospital (OR 1.40, 1.29 -1.47) and unplanned intubation (OR 2.76, 2.52-3.03). DISCUSSION: ISS, PHAR, diabetes, male gender, care at a teaching hospital and unplanned intubation are risk factors for the development of VAP. These factors should be accounted for in order to make VAP an effective quality marker.
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Pneumonia Associada à Ventilação Mecânica , Feminino , Humanos , Escala de Gravidade do Ferimento , Unidades de Terapia Intensiva , Masculino , Pneumonia Associada à Ventilação Mecânica/epidemiologia , Respiração Artificial , Estudos RetrospectivosRESUMO
OBJECTIVES: Utilization of ultrasound in the evaluation of patients with undifferentiated hypotension has been proposed in several protocols. We sought to assess the impact of an ultrasound hypotension protocol on physicians' diagnostic certainty, diagnostic ability, and treatment and resource utilization. DESIGN: Prospective observational study. SETTING: Emergency department in a single, academic tertiary care hospital. SUBJECTS: A convenience sample of patients with a systolic blood pressure less than 90 mm Hg after an initial fluid resuscitation, who lacked an obvious source of hypotension. INTERVENTIONS: An ultrasound-trained physician performed an ultrasound on each patient using a standardized hypotension protocol. Differential diagnosis and management plan was solicited from the treating physician immediately before and after the ultrasound. Blinded chart review was conducted for management and diagnosis during the emergency department and inpatient hospital stay. MEASUREMENTS AND MAIN RESULTS: The primary endpoints were the identification of an accurate cause for hypotension and change in physicians' diagnostic uncertainty. The secondary endpoints were changes in treatment plan, use of resources, and changes in disposition after performing the ultrasound. One hundred eighteen patients with a mean age of 62 years were enrolled. There was a significant 27.7% decrease in the mean aggregate complexity of diagnostic uncertainty before and after the ultrasound hypotension protocol (1.85-1.34; -0.51 [95% CI, -0.41 to -0.62]) as well as a significant increase in the absolute proportion of patients with a definitive diagnosis from 0.8% to 12.7%. Overall, the leading diagnosis after the ultrasound hypotension protocol demonstrated excellent concordance with the blinded consensus final diagnosis (Cohen k = 0.80). Twenty-nine patients (24.6%) had a significant change in the use of IV fluids, vasoactive agents, or blood products. There were also significant changes in major diagnostic imaging (30.5%), consultation (13.6%), and emergency department disposition (11.9%). CONCLUSIONS: Clinical management involving the early use of ultrasound in patients with hypotension accurately guides diagnosis, significantly reduces physicians' diagnostic uncertainty, and substantially changes management and resource utilization in the emergency department.
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Serviço Hospitalar de Emergência , Hipotensão/diagnóstico por imagem , Hipotensão/diagnóstico , Hipotensão/terapia , Sistemas Automatizados de Assistência Junto ao Leito , Ressuscitação/métodos , Idoso , Pressão Sanguínea , Transfusão de Sangue/métodos , Fármacos Cardiovasculares/administração & dosagem , Protocolos Clínicos , Cuidados Críticos , Diagnóstico Diferencial , Feminino , Hidratação/métodos , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Ultrassonografia , IncertezaRESUMO
Background: Bandemia, defined as a band count >10%, is indicative of underlying infection and is increasingly being used for early detection of sepsis. While an absolute band level has been linked to worse outcomes, its trend has not been extensively studied as a prognostic marker. In this study, we assessed patients admitted to the ICU with sepsis or septic shock and evaluated the correlation between bandemia trends and clinical trajectory among these patients. Methods: This study was a retrospective chart review. Band counts, serum lactate levels, and SOFA scores at 0 and 72 h after admission to the ICU were collected. Patients were risk stratified into groups depending on their SOFA trends, and corresponding band trends and serum lactate levels were compared. Results: 134 patients were included for analysis. There was a statistically significant decrease in bandemia trends for patients with a reduction in SOFA scores [median (IQR)-4.5 (-11, 0); p < 0.0001], and a statistically significant increase in bandemia trends for patients with worsening SOFA scores [median (IQR) 4 (0, 8); p = 0.0007]. Conclusion: Early trends of serum band levels in patients with sepsis or septic shock may help to predict a clinical trajectory and overall prognosis. More investigation is warranted as to whether incorporating bandemia trends, when used in conjunction with other known markers such as lactate levels, may help to guide bedside clinical decisions such as risk stratification, tailored therapies, and ultimately improve outcomes.
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Importance: Prior observational studies suggest that aspirin use may be associated with reduced mortality in high-risk hospitalized patients with COVID-19, but aspirin's efficacy in patients with moderate COVID-19 is not well studied. Objective: To assess whether early aspirin use is associated with lower odds of in-hospital mortality in patients with moderate COVID-19. Design, Setting, and Participants: Observational cohort study of 112â¯269 hospitalized patients with moderate COVID-19, enrolled from January 1, 2020, through September 10, 2021, at 64 health systems in the United States participating in the National Institute of Health's National COVID Cohort Collaborative (N3C). Exposure: Aspirin use within the first day of hospitalization. Main Outcome and Measures: The primary outcome was 28-day in-hospital mortality, and secondary outcomes were pulmonary embolism and deep vein thrombosis. Odds of in-hospital mortality were calculated using marginal structural Cox and logistic regression models. Inverse probability of treatment weighting was used to reduce bias from confounding and balance characteristics between groups. Results: Among the 2â¯446â¯650 COVID-19-positive patients who were screened, 189â¯287 were hospitalized and 112â¯269 met study inclusion. For the full cohort, Median age was 63 years (IQR, 47-74 years); 16.1% of patients were African American, 3.8% were Asian, 52.7% were White, 5.0% were of other races and ethnicities, 22.4% were of unknown race and ethnicity. In-hospital mortality occurred in 10.9% of patients. After inverse probability treatment weighting, 28-day in-hospital mortality was significantly lower in those who received aspirin (10.2% vs 11.8%; odds ratio [OR], 0.85; 95% CI, 0.79-0.92; P < .001). The rate of pulmonary embolism, but not deep vein thrombosis, was also significantly lower in patients who received aspirin (1.0% vs 1.4%; OR, 0.71; 95% CI, 0.56-0.90; P = .004). Patients who received early aspirin did not have higher rates of gastrointestinal hemorrhage (0.8% aspirin vs 0.7% no aspirin; OR, 1.04; 95% CI, 0.82-1.33; P = .72), cerebral hemorrhage (0.6% aspirin vs 0.4% no aspirin; OR, 1.32; 95% CI, 0.92-1.88; P = .13), or blood transfusion (2.7% aspirin vs 2.3% no aspirin; OR, 1.14; 95% CI, 0.99-1.32; P = .06). The composite of hemorrhagic complications did not occur more often in those receiving aspirin (3.7% aspirin vs 3.2% no aspirin; OR, 1.13; 95% CI, 1.00-1.28; P = .054). Subgroups who appeared to benefit the most included patients older than 60 years (61-80 years: OR, 0.79; 95% CI, 0.72-0.87; P < .001; >80 years: OR, 0.79; 95% CI, 0.69-0.91; P < .001) and patients with comorbidities (1 comorbidity: 6.4% vs 9.2%; OR, 0.68; 95% CI, 0.55-0.83; P < .001; 2 comorbidities: 10.5% vs 12.8%; OR, 0.80; 95% CI, 0.69-0.93; P = .003; 3 comorbidities: 13.8% vs 17.0%, OR, 0.78; 95% CI, 0.68-0.89; P < .001; >3 comorbidities: 17.0% vs 21.6%; OR, 0.74; 95% CI, 0.66-0.84; P < .001). Conclusions and Relevance: In this cohort study of US adults hospitalized with moderate COVID-19, early aspirin use was associated with lower odds of 28-day in-hospital mortality. A randomized clinical trial that includes diverse patients with moderate COVID-19 is warranted to adequately evaluate aspirin's efficacy in patients with high-risk conditions.
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Aspirina , COVID-19 , Adulto , Aspirina/uso terapêutico , Estudos de Coortes , Mortalidade Hospitalar , Hospitalização , Humanos , Pessoa de Meia-Idade , Estados Unidos/epidemiologiaRESUMO
INTRODUCTION: Adult respiratory distress syndrome (ARDS) is a well-described complication of critical illness. We hy-pothesized that rates of comorbid diseases in a population may influence the risk for developing ARDS in trauma pa-tients. This can help plan medical responses. METHODS: Patients from the 2017 National Trauma Databank were analyzed. Inclusion criteria were an injury sever-ity score (ISS) of ≥ 2 and 1 or more documented days of mechanical ventilation. Data were analyzed using χ2, Student's t test, Mann-Whitney U test, or logistic regression as indicated. RESULTS: Diabetes (odds ratio [OR] 1.33, 95 percent confidence interval [CI] 1.17-1.52), smoking (OR 1.26, 95 per-cent CI 1.13-1.40), transfusion (OR 1.20, 95 percent CI 1.09-1.32), ISS (OR 1.02, 95 percent CI 1.02-1.03), male gen-der (OR 1.22, 95 percent CI 1.10-1.35), decreasing Glasgow coma score (OR 1.04, 95 percent CI 1.03-1.05), and in-creasing abbreviated injury score of the thorax (OR 1.12, 95 percent CI 1.09-1.16) were associated with an increase in risk for developing ARDS. CONCLUSION: Diabetes and smoking are risk factors for developing ARDS after trauma. Medical response planning in countries with high rates of diabetes mellitus or smoking should take into account a greater need for intensive care and longer patient admissions to field hospitals.
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Desastres , Síndrome do Desconforto Respiratório , Adulto , Humanos , Modelos Logísticos , Masculino , Respiração Artificial , Síndrome do Desconforto Respiratório/epidemiologia , Fatores de RiscoRESUMO
CONTEXT: Vasopressors are commonly administered through Central Venous Catheters (CVCs) as it is considered unsafe to administer them via peripheral IVs, mainly due to the concern of local tissue injury. Unlike peripheral IVs, midline catheters provide a wider lumen with the catheter tip ending in a large peripheral vein. The use of vasopressors through midline catheters has not yet been evaluated. OBJECTIVE: The primary objective of this study is to determine the safety and efficacy of long term administration of vasopressors through a midline catheter. DESIGN: This is a retrospective study between 2016 and 2019 looking at the outcomes of midline catheters. SETTING: 45 bed Tertiary level ICU in a 600-bed teaching hospital. PATIENTS: A total of 248 patients received vasopressors via midline catheters. RESULTS: The average midline dwell time was 14.7 ± 12.8 days and the average duration of continuous vasopressor infusion was 7.8 ± 9.3 days. Vasopressors used with their average dose (AD) were norepinephrine (n = 165, 16.8 CE ± 10.7 µg/min), epinephrine (n = 56, 9.1 CE ± 6.0 µg/min), vasopressin (n = 123, 0.05 CE ± 0.02 units/min), phenylephrine (n = 158, 91.4 CE ± 64.7 µg/min) and Angiotensin II (50 CE ± 27.6 ng/kg/min). Early Complication rate was 3.6% due to Bloodstream infection (n = 6), drug extravasation (n = 1), thrombophlebitis (n = 1) and arterial puncture (n = 1). Late Complication rate was 0.8% (n = 2) due to midline-associated DVTs. There were no complications related to ineffective drug delivery or limb endangerment. CONCLUSIONS: Many medical centers are attempting to limit the use of central venous catheters (CVCs) to avoid central line-associated bloodstream infections (CLABSIs). This study demonstrates that midline catheters are a safe alternative to CVCs, for the safe and efficacious administration of vasopressors for prolonged periods of time.
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Infecções Relacionadas a Cateter , Cateterismo Venoso Central , Cateterismo Periférico , Cateteres Venosos Centrais , Infecções Relacionadas a Cateter/epidemiologia , Cateterismo Venoso Central/efeitos adversos , Cateterismo Periférico/efeitos adversos , Cateteres Venosos Centrais/efeitos adversos , Humanos , Fenilefrina , Estudos Retrospectivos , Vasoconstritores/efeitos adversosRESUMO
BACKGROUND: COVID-19 infection is associated with D-dimer elevations, high rates of thrombus formation, and poor clinical outcomes. We sought to determine if empiric therapeutic anticoagulation (AC) affected survival in COVID-19 patients compared to standard prophylactic AC. METHODS: Retrospective analysis of 402 COVID-19 patients hospitalized between March 15 and May 31, 2020 was performed. Clinical outcomes were compared between 152 patients treated with therapeutic AC to 250 patients on prophylactic AC. An elastic net logistic regression was designed to first identify the important variables affecting mortality. These variables were then included as covariates to AC in standard multivariate logistic regression models studying the effect of AC on death. Nonparametric survival analysis was conducted, and Kaplan Meier curves were constructed. RESULTS: Increased mortality was associated with therapeutic AC [OR 3.42 (2.06, 5.67)]. The log-rank test was statistically significant at p = 0.001 showing higher mortality for patients treated with therapeutic AC compared to prophylactic AC. Subset analysis of critically ill and intubated patients had similar survival curves regardless of AC dose. The log-rank test was not significant even with Prentice modification. For non-ICU patients, the log rank test favoring prophylactic AC disappeared when the analysis was stratified by D-dimer level less or greater than 3 µg/mL. Approximately 9% of patients receiving therapeutic AC experienced clinically significant bleeding or thrombocytopenia, versus 3% in those receiving prophylactic AC. CONCLUSIONS: In our cohort, therapeutic anticoagulation provided no mortality benefit over thromboprophylaxis, independent of co-morbidities or disease severity. More adverse events were observed with therapeutic AC.
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COVID-19 , Tromboembolia Venosa , Anticoagulantes/uso terapêutico , Humanos , Prevalência , Estudos Retrospectivos , SARS-CoV-2RESUMO
PURPOSE: Coronavirus disease 2019 (COVID-19) is associated with hypercoagulability and increased thrombotic risk. The impact of prehospital antiplatelet therapy on in-hospital mortality is uncertain. METHODS: This was an observational cohort study of 34 675 patients ≥50 years old from 90 health systems in the United States. Patients were hospitalized with laboratory-confirmed COVID-19 between February 2020 and September 2020. For all patients, the propensity to receive prehospital antiplatelet therapy was calculated using demographics and comorbidities. Patients were matched based on propensity scores, and in-hospital mortality was compared between the antiplatelet and non-antiplatelet groups. RESULTS: The propensity score-matched cohort of 17 347 patients comprised of 6781 and 10 566 patients in the antiplatelet and non-antiplatelet therapy groups, respectively. In-hospital mortality was significantly lower in patients receiving prehospital antiplatelet therapy (18.9% vs. 21.5%, p < .001), resulting in a 2.6% absolute reduction in mortality (HR: 0.81, 95% CI: 0.76-0.87, p < .005). On average, 39 patients needed to be treated to prevent one in-hospital death. In the antiplatelet therapy group, there was a significantly lower rate of pulmonary embolism (2.2% vs. 3.0%, p = .002) and higher rate of epistaxis (0.9% vs. 0.4%, p < .001). There was no difference in the rate of other hemorrhagic or thrombotic complications. CONCLUSIONS: In the largest observational study to date of prehospital antiplatelet therapy in patients with COVID-19, there was an association with significantly lower in-hospital mortality. Randomized controlled trials in diverse patient populations with high rates of baseline comorbidities are needed to determine the ultimate utility of antiplatelet therapy in COVID-19.
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COVID-19 , Serviços Médicos de Emergência , Mortalidade Hospitalar , Humanos , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/efeitos adversos , Pontuação de Propensão , Estudos Retrospectivos , SARS-CoV-2 , Estados Unidos/epidemiologiaRESUMO
Importance: Long-term immune sequelae after sepsis are poorly understood. Objective: To assess whether abnormalities in the host immune response during hospitalization for sepsis persist after discharge. Design, Settings, and Participants: This prospective, multicenter cohort study enrolled and followed up for 1 year adults who survived a hospitalization for sepsis from January 10, 2012, to May 25, 2017, at 12 US hospitals. Exposures: Circulating levels of inflammation (interleukin 6 and high-sensitivity C-reactive protein [hs-CRP]), immunosuppression (soluble programmed death ligand 1 [sPD-L1]), hemostasis (plasminogen activator inhibitor 1 and D-dimer), endothelial dysfunction (E-selectin, intercellular adhesion molecule 1, and vascular cell adhesion molecule 1), and oxidative stress biomarkers were measured at 5 time points during and after hospitalization for sepsis for 1 year. Individual biomarker trajectories and patterns of trajectories across biomarkers (phenotypes) were identified. Main Outcomes and Measures: Outcomes were adjudicated centrally and included all-cause and cause-specific readmissions and mortality. Results: A total of 483 patients (mean [SD] age, 60.5 [15.2] years; 265 [54.9%] male) who survived hospitalization for sepsis were included in the study. A total of 376 patients (77.8%) had at least 1 chronic disease, and their mean (SD) Sequential Organ Failure Assessment score was 4.2 (3.0). Readmissions were common (485 readmissions in 205 patients [42.5%]), and 43 patients (8.9%) died by 3 months, 56 patients (11.6%) died by 6 months, and 85 patients (17.6%) died by 12 months. Elevated hs-CRP levels were observed in 23 patients (25.8%) at 3 months, 26 patients (30.2%) at 6 months, and 23 patients (25.6%) at 12 months, and elevated sPD-L1 levels were observed in 45 patients (46.4%) at 3 months, 40 patients (44.9%) at 6 months, and 44 patients (49.4%) at 12 months. Two common phenotypes were identified based on hs-CRP and sPDL1 trajectories: high hs-CRP and sPDL1 levels (hyperinflammation and immunosuppression phenotype [326 of 477 (68.3%)]) and normal hs-CRP and sPDL1 levels (normal phenotype [143 of 477 (30.0%)]). These phenotypes had similar clinical characteristics and clinical course during hospitalization for sepsis. Compared with normal phenotype, those with the hyperinflammation and immunosuppression phenotype had higher 1-year mortality (odds ratio, 8.26; 95% CI, 3.45-21.69; P < .001), 6-month all-cause readmission or mortality (hazard ratio [HR], 1.53; 95% CI, 1.10-2.13; P = .01), and 6-month readmission or mortality attributable to cardiovascular disease (HR, 5.07; 95% CI, 1.18-21.84; P = .02) or cancer (HR, 5.15; 95% CI, 1.25-21.18; P = .02). These associations were adjusted for demographic characteristics, chronic diseases, illness severity, organ support, and infection site during sepsis hospitalization and were robust in sensitivity analyses. Conclusions and Relevance: In this study, persistent elevation of inflammation and immunosuppression biomarkers occurred in two-thirds of patients who survived a hospitalization for sepsis and was associated with worse long-term outcomes.
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Imunocompetência/imunologia , Inflamação/sangue , Sepse/imunologia , Idoso , Antígeno B7-H1/sangue , Biomarcadores/sangue , Proteína C-Reativa/análise , Comorbidade , Feminino , Humanos , Inflamação/imunologia , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Readmissão do Paciente/estatística & dados numéricos , Estudos Prospectivos , Sepse/sangue , Sepse/mortalidadeRESUMO
BACKGROUND: Gait initiation can be performed at a range of speeds. Those with disability tend to use a slower speed compared to those without disability. In assessing the spatiotemporal and kinematic characteristics of gait initiation it is therefore important to consider the effects of speed on outcomes. RESEARCH QUESTION: What is the effect of speed of performance on spatiotemporal and kinematic characteristics of gait initiation? METHODS: Spatiotemporal and kinematic characteristics were measured across a wide range of speeds from very slow to very fast (normalised initiating leg (swing or SW limb) step speed 0.1-0.5) for 20 health adults (10 men/10 women, 22-44 years) using three-dimensional motion analysis of the first two steps of gait. RESULTS: Mixed linear modelling of 295 walking trials indicated differences between individuals, sexes and strong non-linear relationships between normalised initiating leg step speed and cadence and step lengths (R2â¯>â¯0.5). Particular characteristics of joint kinematics (maxima and minima for both initiating (SW) and contralateral limb (stance or ST limb)) demonstrated significant non-linear (squared, cubic and power law) changes with speed. Moderate to strong relationships were identified for sagittal plane pelvis, hip and knee kinematics as well as hip adduction (0.3â¯<â¯R2â¯<â¯0.7). SIGNIFICANCE: Gait initiation spatiotemporal and kinematic characteristics were quantified across the maximum range of speeds achievable, providing comprehensive characterisation of changes with speed. Significant, non-linear changes with speed were identified, suggesting different strategies are employed to modify speed at low and high speeds. The highlighted changes with speed illustrate the importance of taking speed into account when comparing outcomes between healthy adults and those with pathology.
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Marcha/fisiologia , Velocidade de Caminhada/fisiologia , Caminhada/fisiologia , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Extremidade Inferior/fisiologia , Masculino , Amplitude de Movimento Articular/fisiologia , Análise Espaço-TemporalRESUMO
In exploring the relationship between the kinematics of gait and speed of progression individual variation in patterns and gender differences have not always been adequately taken into account. In the current study mixed linear modelling was used to isolate changes with speed from those associated with individual variation and gender. Three-dimensional motion analysis of 20 participants (10M/10F, 25.7⯱â¯5.1 years) walking at a wide range of speeds (normalised speeds 0.10-0.55 â¼0.41-2.26â¯m/s) was recorded (775 walks). Spatiotemporal (speed, cadence, step length, percentage of single and double support) and kinematic characteristics (pelvis through ankle) were determined. Significant between participant differences were highlighted in both intercept and slope of relationships. In addition females exhibiting different peak pelvic tilt and obliquity, hip flexion and internal rotation and ankle dorsiflexion compared to males. Spatiotemporal parameters exhibited non-linear relationships with normalised speed (R2â¯>â¯0.5). Kinematic features exhibited significant relationships with normalised speed, varying from linear to cubic, from very weak to strong in fit (0.010â¯>â¯R2â¯>â¯0.672). Mixed linear modelling highlighted gender dependent, speed related changes in addition to inter-individual variation. Gender and speed are both important determinants of gait patterns, however, individual variations remain.