Estudio comparativo de modelos de comportamiento de amplificadores de potencia RF

Tesis de Maestría en ciencias en sistemas digitales

Prospective cohort study of incidence and risk factors for catheter-associated urinary tract infections in 145 intensive care units of 9 Latin American countries: INICC findings

Purpose: Identify urinary catheter (UC)-associated urinary tract infections (CAUTI) incidence and risk factors (RF) in Latin American Countries. Methods: From 01/01/2014 to 02/10/2022, we conducted a prospective cohort study in 145 ICUs of 67 hospitals in 35 cities in nine Latin American countries: Argentina, Brazil, Colombia, Costa Rica, Dominican Republic, Ecuador, Mexico, Panama, and Peru. To estimate CAUTI incidence, we used the number of UC-days as the denominator, and the number of CAUTIs as numerator. To estimate CAUTI RFs, we analyzed the following 10 variables using multiple logistic regression: gender, age, length of stay (LOS) before CAUTI acquisition, UC-days before CAUTI acquisition, UC-device utilization (DU) ratio, UC-type, hospitalizationtype, ICU type, facility ownership, and time period. Results: 31,631 patients, hospitalized for 214,669 patient-days, acquired 305 CAUTIs. The pooled CAUTI rate per 1000 UC-days was 2.58, for those using suprapubic catheters, it was 2.99, and for those with indwelling catheters, it was 2.21. The following variables were independently associated with CAUTI: age, rising risk 1% yearly (aOR = 1.01; 95% CI 1.01–1.02; p < 0.0001 female gender (aOR = 1.28; 95% CI 1.01–1.61; p = 0.04), LOS before CAUTI acquisition, rising risk 7% daily (aOR = 1.07; 95% CI 1.06–1.08; p < 0.0001, UC/DU ratio (aOR = 1.14; 95% CI 1.08–1.21; p < 0.0001, public facilities (aOR = 2.89; 95% CI 1.75–4.49; p < 0.0001. The periods 2014–2016 and 2017–2019 had significantly higher risks than the period 2020–2022. Suprapubic catheters showed similar risks as indwelling catheters. Conclusion: The following CAUTI RFs are unlikely to change: age, gender, hospitalization type, and facility ownership. Based on these findings, it is suggested to focus on reducing LOS, UC/DU ratio, and implementing evidence-based CAUTI prevention recommendations.Revisión por pare

Multinational prospective cohort study of incidence and risk factors for central line-associated bloodstream infections in ICUs of 8 Latin American countries

Background: Our objective was to identify central line (CL)-associated bloodstream infections (CLABSI) rates and risk factors in Latin-America. Methods: From January 1, 2014 to February 10, 2022, we conducted a multinational multicenter prospective cohort study in 58 ICUs of 34 hospitals in 21 cities in 8 Latin American countries (Argentina, Brazil, Colombia, Costa Rica, Dominican Republic, Ecuador, Mexico, Panama). We applied multiple-logistic regression. Outcomes are shown as adjusted-odds ratios (aOR). Results: About 29,385 patients were hospitalized during 92,956 days, acquired 400 CLABSIs, and pooled CLABSI rate was 4.30 CLABSIs per 1,000 CL-days. We analyzed following 10 variables: Gender, age, length of stay (LOS) before CLABSI acquisition, CL-days before CLABSI acquisition, CL-device utilization (DU) ratio, CL-type, tracheostomy use, hospitalization type, intensive care unit (ICU) type, and facility ownership, Following variables were independently associated with CLABSI: LOS before CLABSI acquisition, rising risk 3% daily (aOR=1.03;95%CI=1.02-1.04; P < .0001); number of CL-days before CLABSI acquisition, rising risk 4% per CL-day (aOR=1.04;95%CI=1.03-1.05; P < .0001); publicly-owned facility (aOR=2.33;95%CI=1.79-3.02; P < .0001). ICU with highest risk was medical-surgical (aOR=2.61;95%CI=1.41-4.81; P < .0001). CL with the highest risk were femoral (aOR=2.71;95%CI=1.61-4.55; P < .0001), and internal-jugular (aOR=2.62;95%CI=1.82-3.79; P < .0001). PICC (aOR=1.25;95%CI=0.63-2.51; P = .52) was not associated with CLABSI risk. Conclusions: Based on these findings it is suggested to focus on reducing LOS, CL-days, using PICC instead of femoral or internal-jugular; and implementing evidence-based CLABSI prevention recommendations.Revisión por pare

Risk of COVID-19 after natural infection or vaccinationResearch in context

Summary: Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7–15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05–0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01–0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health

Risk of COVID-19 after natural infection or vaccinationResearch in context

Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7–15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05–0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01–0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health

Global economic burden of unmet surgical need for appendicitis

Background There is a substantial gap in provision of adequate surgical care in many low- and middle-income countries. This study aimed to identify the economic burden of unmet surgical need for the common condition of appendicitis. Methods Data on the incidence of appendicitis from 170 countries and two different approaches were used to estimate numbers of patients who do not receive surgery: as a fixed proportion of the total unmet surgical need per country (approach 1); and based on country income status (approach 2). Indirect costs with current levels of access and local quality, and those if quality were at the standards of high-income countries, were estimated. A human capital approach was applied, focusing on the economic burden resulting from premature death and absenteeism. Results Excess mortality was 4185 per 100 000 cases of appendicitis using approach 1 and 3448 per 100 000 using approach 2. The economic burden of continuing current levels of access and local quality was US $92 492 million using approach 1 and$73 141 million using approach 2. The economic burden of not providing surgical care to the standards of high-income countries was $95 004 million using approach 1 and$75 666 million using approach 2. The largest share of these costs resulted from premature death (97.7 per cent) and lack of access (97.0 per cent) in contrast to lack of quality. Conclusion For a comparatively non-complex emergency condition such as appendicitis, increasing access to care should be prioritized. Although improving quality of care should not be neglected, increasing provision of care at current standards could reduce societal costs substantially

Global economic burden of unmet surgical need for appendicitis

Background There is a substantial gap in provision of adequate surgical care in many low- and middle-income countries. This study aimed to identify the economic burden of unmet surgical need for the common condition of appendicitis. Methods Data on the incidence of appendicitis from 170 countries and two different approaches were used to estimate numbers of patients who do not receive surgery: as a fixed proportion of the total unmet surgical need per country (approach 1); and based on country income status (approach 2). Indirect costs with current levels of access and local quality, and those if quality were at the standards of high-income countries, were estimated. A human capital approach was applied, focusing on the economic burden resulting from premature death and absenteeism. Results Excess mortality was 4185 per 100 000 cases of appendicitis using approach 1 and 3448 per 100 000 using approach 2. The economic burden of continuing current levels of access and local quality was US $92 492 million using approach 1 and$73 141 million using approach 2. The economic burden of not providing surgical care to the standards of high-income countries was $95 004 million using approach 1 and$75 666 million using approach 2. The largest share of these costs resulted from premature death (97.7 per cent) and lack of access (97.0 per cent) in contrast to lack of quality. Conclusion For a comparatively non-complex emergency condition such as appendicitis, increasing access to care should be prioritized. Although improving quality of care should not be neglected, increasing provision of care at current standards could reduce societal costs substantially