Effect of time to onset on clinical features and prognosis of post-sternotomy mediastinitis

AbstractIncubation time affects the clinical features and outcome of many nosocomial infections. However, its role in the setting of post-sternotomy mediastinitis (PSM) has not been specifically studied. The present study aimed to evaluate the impact of time to onset of PSM on the clinical presentation and outcomes of patients. Hospital records of 197 patients who developed PSM over a 10-year period and were treated by closed drainage using Redon catheters were reviewed retrospectively. Follow-up was complete for all included patients (median of 19 months); 98 patients developed early-onset PSM (time from initial operation to PSM <14 days) and 99 patients had late-onset PSM (≥14 days). Patients with late-onset PSM had a higher rate of internal thoracic artery harvest and mediastinal re-exploration after initial operation. Patients with early-onset PSM presented more frequently with septic shock. Microbiological findings differed between early- and late-onset PSM by a higher incidence of Enterococcus species in the former and of Staphylococcus aureus in the latter. Overall mortality reached 34% (n = 66). Rates of superinfection, treatment failure, mediastinitis-related death, mortality at 1 year and overall mortality were all significantly higher in patients with early-onset PSM. Multiple regression procedures identified early-onset PSM as a significant and independent risk factor for both 1-year (OR 2.40; 95% CI 1.12-5.11) and overall (OR 2.11; 95% 1.26-3.53) mortality. In conclusion, the results obtained in the present study support the distinction between early- and late-onset PSM with different clinical and pathophysiological features. Early-onset PSM is associated with a significantly higher morbidity and mortality compared to late-onset PSM

Development of a biomarker mortality risk model in acute respiratory distress syndrome

Background: There is a compelling unmet medical need for biomarker-based models to risk-stratify patients with acute respiratory distress syndrome. Effective stratification would optimize participant selection for clinical trial enrollment by focusing on those most likely to benefit from new interventions. Our objective was to develop a prognostic, biomarker-based model for predicting mortality in adult patients with acute respiratory distress syndrome. Methods: This is a secondary analysis using a cohort of 252 mechanically ventilated subjects with the diagnosis of acute respiratory distress syndrome. Survival to day 7 with both day 0 (first day of presentation) and day 7 sample availability was required. Blood was collected for biomarker measurements at first presentation to the intensive care unit and on the seventh day. Biomarkers included cytokine-chemokines, dual-functioning cytozymes, and vascular injury markers. Logistic regression, latent class analysis, and classification and regression tree analysis were used to identify the plasma biomarkers most predictive of 28-day ARDS mortality. Results: From eight biologically relevant biomarker candidates, six demonstrated an enhanced capacity to predict mortality at day 0. Latent-class analysis identified two biomarker-based phenotypes. Phenotype A exhibited significantly higher plasma levels of angiopoietin-2, macrophage migration inhibitory factor, interleukin-8, interleukin-1 receptor antagonist, interleukin-6, and extracellular nicotinamide phosphoribosyltransferase (eNAMPT) compared to phenotype B. Mortality at 28 days was significantly higher for phenotype A compared to phenotype B (32% vs 19%, p = 0.04). Conclusions: An adult biomarker-based risk model reliably identifies ARDS subjects at risk of death within 28 days of hospitalization.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Comparison and evaluation of experimental mediastinitis models: precolonized foreign body implants and bacterial suspension inoculation seems promising

BACKGROUND: Post-sternotomy mediastinitis (PSM) is a devastating surgical complication affecting 1–3% of patients that undergo cardiac surgery. Staphylococcus aureus is one of the most commonly encountered bacterial pathogen cultured from mediastinal samples obtained from patients with PSM. A component of the membrane of the gram positive bacteria, lipoteichoic acid, stimulates the blood monocytes and macrophages to secrete cytokines, radicals and nitrogen species leading to oxido-inflammatory damage. This seems to be responsible for the high mortality rate in PSM. For the evaluation of the pathogenesis of infection or for the investigation of alternative treatment models in infection, no standard model of mediastinitis seems to be available. In this study, we evaluated four mediastinitis models in rats. METHODS: The rats were divided into four groups to form different infection models. Group A: A suspension of 1 × 10(7 )colony-forming units Staphylococcus aureus in 0,5 mL was inoculated from the right second intercostal space into the mediastinum. Group B: A hole was created in the right second intercostal space and a piece of stainless-steel implant with a length of 0.5 cm was inserted into the mediastinum and a suspension of 1 × 10(7 )cfu bacteria in 0,5 mL was administered via the tail vein. Group C: Precolonized stainless-steel implant was inserted into the mediastinum. Group D: Precolonized stainless-steel implant was inserted into the mediastinum and the bacteria suspension was also injected into the mediastinum. On the 10(th )day, rats were sacrificed and the extension of infection in the mediastenae was evaluated by quantitative cultures. Myeloperoxidase activity (MPO) and malondialdehyde (MDA) levels were determined in the sera to evaluate the neutrophil activation and assess the inflammatory oxidation. RESULTS: The degree of infection in group C and D were 83.3% and 100% respectively (P < 0.001). MDA levels were significantly higher in these two groups than the others (P < 0.001). CONCLUSION: Infected implants and high bacterial concentration administration were the two important components that played a significant role in the outcome of a successful infection in mediastinum in a rat model

Relation of tricuspid annular displacement and tissue Doppler imaging velocities with duration of weaning in mechanically ventilated patients with acute pulmonary edema

<p>Abstract</p> <p>Background</p> <p>Liberation from the ventilator is a difficult task, whereas early echocardiographic indices of weaning readiness are still lacking. The aim of this study was to test whether tricuspid annular plane systolic excursion (TAPSE) and right ventricular (RV) systolic (Sm) and diastolic (Em & Am) tissue Doppler imaging (TDI) velocities are related with duration of weaning in mechanically ventilated patients with acute respiratory failure due to acute pulmonary edema (APE).</p> <p>Methods</p> <p>Detailed quantification of left and right ventricular systolic and diastolic function was performed at admission to the Intensive Care Unit by Doppler echocardiography, in a cohort of 32 mechanically ventilated patients with APE. TAPSE and RV TDI velocities were compared between patients with and without prolonged weaning (≥ or < 7 days from the first weaning trial respectively), whereas their association with duration of ventilation and left ventricular (LV) echo-derived indices was tested with multivariate linear and logistic regression analysis.</p> <p>Results</p> <p>Patients with prolonged weaning (n = 12) had decreased TAPSE (14.59 ± 1.56 vs 19.13 ± 2.59 mm), Sm (8.68 ± 0.94 vs 11.62 ± 1.77 cm/sec) and Em/Am ratio (0.98 ± 0.80 vs 2.62 ± 0.67, p <0.001 for all comparisons) and increased Ε/e' (11.31 ± 1.02 vs 8.98 ± 1.70, p <0.001) compared with subjects without prolonged weaning (n = 20). Logistic regression analysis revealed that TAPSE (R²= 0.53, beta slope = 0.76, p < 0.001), Sm (R²= 0.52, beta = 0.75, p < 0.001) and Em/Am (R²= 0.57, beta = 0.32, p < 0.001) can predict length of weaning ≥ 7 days. The above measures were also proven to correlate significantly with Ε/e' (r = -0.83 for TAPSE, r = -0.87 for Sm and r = -0.79 for Em/Am, p < 0.001 for all comparisons).</p> <p>Conclusions</p> <p>We suggest that in mechanically ventilated patients with APE, low TAPSE and RV TDI velocities upon admission are associated with delayed liberation from mechanical ventilation, probably due to more severe LV heart failure.</p

The role for high flow nasal cannula as a respiratory support strategy in adults: a clinical practice guideline

Purpose: High flow nasal cannula (HFNC) is a relatively recent respiratory support technique which delivers high flow, heated and humidified controlled concentration of oxygen via the nasal route. Recently, its use has increased for a variety of clinical indications. To guide clinical practice, we developed evidence-based recommendations regarding use of HFNC in various clinical settings. Methods: We formed a guideline panel composed of clinicians, methodologists and experts in respiratory medicine. Using GRADE, the panel developed recommendations for four actionable questions. Results: The guideline panel made a strong recommendation for HFNC in hypoxemic respiratory failure compared to conventional oxygen therapy (COT) (moderate certainty), a conditional recommendation for HFNC following extubation (moderate certainty), no recommendation regarding HFNC in the peri-intubation period (moderate certainty), and a conditional recommendation for postoperative HFNC in high risk and/or obese patients following cardiac or thoracic surgery (moderate certainty). Conclusions: This clinical practice guideline synthesizes current best-evidence into four recommendations for HFNC use in patients with hypoxemic respiratory failure, following extubation, in the peri-intubation period, and postoperatively for bedside clinicians

Echocardiography findings in COVID-19 patients admitted to intensive care units: a multi-national observational study (the ECHO-COVID study)

Purpose: Severely ill patients affected by coronavirus disease 2019 (COVID-19) develop circulatory failure. We aimed to report patterns of left and right ventricular dysfunction in the first echocardiography following admission to intensive care unit (ICU). Methods: Retrospective, descriptive study that collected echocardiographic and clinical information from severely ill COVID-19 patients admitted to 14 ICUs in 8 countries. Patients admitted to ICU who received at least one echocardiography between 1st February 2020 and 30th June 2021 were included. Clinical and echocardiographic data were uploaded using a secured web-based electronic database (REDCap). Results: Six hundred and seventy-seven patients were included and the first echo was performed 2 [1, 4] days after ICU admission. The median age was 65 [56, 73] years, and 71% were male. Left ventricle (LV) and/or right ventricle (RV) systolic dysfunction were found in 234 (34.5%) patients. 149 (22%) patients had LV systolic dysfunction (with or without RV dysfunction) without LV dilatation and no elevation in filling pressure. 152 (22.5%) had RV systolic dysfunction. In 517 patients with information on both paradoxical septal motion and quantitative RV size, 90 (17.4%) had acute cor pulmonale (ACP). ACP was associated with mechanical ventilation (OR &gt; 4), pulmonary embolism (OR &gt; 5) and increased PaCO2. Exploratory analyses showed that patients with ACP and older age were more likely to die in hospital (including ICU). Conclusion: Almost one-third of this cohort of critically ill COVID-19 patients exhibited abnormal LV and/or RV systolic function in their first echocardiography assessment. While LV systolic dysfunction appears similar to septic cardiomyopathy, RV systolic dysfunction was related to pressure overload due to positive pressure ventilation, hypercapnia and pulmonary embolism. ACP and age seemed to be associated with mortality in this cohort