Lung and diaphragm ultrasound as predictors of success in weaning from mechanical ventilation.

BACKGROUND: Lung and diaphragm ultrasound methods have recently been introduced to predict the outcome of weaning from mechanical ventilation (MV). The aim of this study is to assess the reliability and accuracy of these techniques for predicting successful weaning in critically ill adults. METHODS: We conducted two studies: a cross-sectional interobserver agreement study between two sonographers and a prospective cohort study to assess the accuracy of lung and diaphragm ultrasound for predicting weaning and extubation outcome. For the interobserver agreement study, we included 50 general critical care patients who were consecutively admitted to the ICU. For the predictive accuracy study, we included consecutively 69 patients on MV who were ready for weaning. We assessed interobserver agreement of ultrasound measurements, using the weighted kappa coefficient for LUSm score (modified lung ultrasound score) and the intraclass correlation coefficient (ICC) and Bland-Altman method for TI (diaphragm thickening index). We assessed the predictive value of LUSm and TI in weaning outcome by plotting the corresponding ROC curves. RESULTS: We found adequate interobserver agreement for both LUSm (weighted kappa 0.95) and TI (ICC 0.78, difference according to Bland-Altman analysis ± 12.5%). LUSm showed good-moderate discriminative power for successful weaning and extubation (area under the ROC curve (AUC) for successful weaning 0.80, and sensitivity and specificity at optimal cut-off point 0.76 and 0.73, respectively; AUC for successful extubation 0.78, and optimal sensitivity and specificity 0.76 and 0.47, respectively. TI was more sensitive but less specific for predicting successful weaning (AUC 0.71, optimal sensitivity and specificity 0.93 and 0.48) and successful extubation (AUC 0.76, optimal sensitivity and specificity 0.93 and 0.58). The area under the ROC curve for predicting weaning success was 0.83 for both ultrasound measurements together. CONCLUSIONS: Interobserver agreement was excellent for LUSm and moderate-good for TI. A low TI value or high LUSm value indicates high risk of weaning failure.

Diaphragm and Lung Ultrasound to Predict Weaning Outcome: Systematic Review and Meta-Analysis.

BACKGROUND: Deciding the optimal timing for extubation in patients who are mechanically ventilated can be challenging, and traditional weaning predictor tools are not very accurate. The aim of this systematic review and meta-analysis was to assess the accuracy of lung and diaphragm ultrasound for predicting weaning outcomes in critically ill adults. METHODS: MEDLINE, the Cochrane Library, Web of Science, Scopus, LILACS, Teseo, Tesis Doctorales en Red, and OpenGrey were searched, and the bibliographies of relevant studies were reviewed. Two researchers independently selected studies that met the inclusion criteria and assessed study quality in accordance with the Quality Assessment of Diagnostic Accuracy Studies-2 tool. The summary receiver-operating characteristic curve and pooled diagnostic OR (DOR) were estimated by using a bivariate random effects analysis. Sources of heterogeneity were explored by using predefined subgroup analyses and bivariate meta-regression. RESULTS: Nineteen studies involving 1,071 people were included in the study. For diaphragm thickening fraction, the area under the summary receiver-operating characteristic curve was 0.87, and DOR was 21 (95% CI, 11-40). Regarding diaphragmatic excursion, pooled sensitivity was 75% (95% CI, 65-85); pooled specificity, 75% (95% CI, 60-85); and DOR, 10 (95% CI, 4-24). For lung ultrasound, the area under the summary receiver-operating characteristic curve was 0.77, and DOR was 38 (95% CI, 7-198). Based on bivariate meta-regression analysis, a significantly higher specificity for diaphragm thickening fraction and higher sensitivity for diaphragmatic excursion was detected in studies with applicability concerns. CONCLUSIONS: Lung and diaphragm ultrasound can help predict weaning outcome, but its accuracy may vary depending on the patient subpopulation.

Accuracy of Lung Ultrasonography in the Diagnosis of Pneumonia in Adults: Systematic Review and Meta-Analysis.

BACKGROUND: Some studies suggest that lung ultrasonography could be useful for diagnosing pneumonia; moreover, it has a more favorable safety profile and lower cost than chest radiography and CT. The aim of this study was to assess the accuracy of bedside lung ultrasonography for diagnosing pneumonia in adults through a systematic review and meta-analysis. METHODS: We searched MEDLINE, Scopus, The Cochrane Library, Web of Science, DARE, HTA Database, Google Scholar, LILACS, ClinicalTrials.gov, TESEO, and OpenGrey. In addition, we reviewed the bibliographies of relevant studies. Two researchers independently selected studies that met the inclusion criteria. Quality of the studies was assessed in accordance with the Quality Assessment of Diagnostic Accuracy Studies tool. The summary receiver operating characteristic (SROC) curve and a pooled estimation of the diagnostic odds ratio (DOR) was estimated using a bivariate random-effects analysis. The sources of heterogeneity were explored using predefined subgroup analyses and bivariate meta-regression. RESULTS: Sixteen studies (2,359 participants) were included. There was significant heterogeneity of both sensitivity and specificity according to the Q test, without clear evidence of threshold effect. The area under the SROC curve was 0.93, with a DOR at the optimal cutpoint of 50 (95% CI, 21-120). A tendency toward a higher area under the SROC curve in high-quality studies was detected; however, these differences were not significant after applying the bivariate meta-regression. CONCLUSIONS: Lung ultrasonography can help accurately diagnose pneumonia, and it may be promising as an adjuvant resource to traditional approaches.

Accessibility to Reperfusion Therapy Among Women with Acute Myocardial Infarction: Impact on Hospital Mortality.

BACKGROUND: The available evidence about the effect of gender and/or sex on mortality differences is contradictory. Our aim is to assess the impact of gender on the access to reperfusion therapy in patients with acute coronary syndrome with ST-segment elevation (STEMI), and secondly, to analyze the effect of delay on the differences with regard to hospital mortality. METHODS: A retrospective cohort study was conducted among consecutive patients with STEMI included in the ARIAM-SEMICYUC registry (2010-2013). RESULTS: A total of 4816 patients were included (22.09% women). Women were older, presented with longer patient delay (90 vs. 75 minutes, p=0.0066), higher risk profile (GRACE>140: 75.1% vs. 56.05%, p<0.0001), and received less reperfusion therapy (68.8% vs. 74.7%, p<0.0001) with longer total reperfusion time (307 vs. 240 minutes, p<0.0001). Women received less thrombolysis (24.53% vs. 29.98%, p<0.0001) and longer door-to-needle time (85 vs. 70 minutes, p 0.0023). We found no differences regarding primary percutaneous coronary intervention or door-to-balloon time. Women also had higher hospital mortality (crude odds ratio 2.54, 95% confidence interval 1.99-3.26, p<0.0001), which persisted after controlling the effect of patient delay, age, risk (GRACE), and reperfusion (adjusted odds ratio 1.43, 95% confidence interval 1.0-2.06, p=0.0492). Using TIMI or Killip risk scores as risk estimates yielded nonsignificant results. CONCLUSIONS: Compared with men, women with STEMI have worse access to reperfusion and higher hospital mortality. The impact of the differences in accessibility on mortality gap remains uncertain.