ROX index as a predictor of failure of high-flow nasal cannula in infants with bronchiolitis.

High-flow nasal cannula (HFNC) is a relatively recent therapy that has been used to treat respiratory failure. Until now, the criterion for failure requiring escalation to other forms of ventilatory support has remained unclear. This study evaluated how the ROX index predicts the success or failure of HFNC in infants with bronchiolitis. A prospective, observational, multicenter study was conducted in 2 pediatric ICUs. The data were collected at 7 moments. Patients were categorized into failure and success groups according to HFNC. A total of 102 infants were included, 18(17.6%) of whom failed HFNC therapy. For the ROX index, significant differences were observed between the failure 5.8(95%CI 4.7-7.1) and success 7.7(95%CI 7.2-8.2) groups (p = 0.005) at the 12 h evaluation. According to the analysis of the performance of the ROX index, the AUC at 12 h was 0.716(95%CI 0.591-0.842; p = 0.016). The best cutoff range for the ROX index at 12 h was 6.50-7.18, with a sensitivity of 42% and a specificity of 66% at the cutoff of 6.50, and a sensitivity of 92% and a specificity of 54% at the cutoff of 7.18. We concluded that the ROX index could be effective at predicting the failure of HFNC therapy in infants with bronchiolitis beginning at 12 h after installation.

High prevalence of respiratory muscle weakness in hospitalized acute heart failure elderly patients.

INTRODUCTION: Respiratory Muscle Weakness (RMW) has been defined when the maximum inspiratory pressure (MIP) is lower than 70% of the predictive value. The prevalence of RMW in chronic heart failure patients is 30 to 50%. So far there are no studies on the prevalence of RMW in acute heart failure (AHF) patients. OBJECTIVES: Evaluate the prevalence of RMW in patients admitted because of AHF and the condition of respiratory muscle strength on discharge from the hospital. METHODS: Sixty-three patients had their MIP measured on two occasions: at the beginning of the hospital stay, after they had reached respiratory, hemodynamic and clinical stability and before discharge from the hospital. The apparatus and technique to measure MIP were adapted because of age-related limitations of the patients. Data on cardiac ejection fraction, ECG, brain natriuretic peptide (BNP) levels and on the use of noninvasive ventilation (NIV) were collected. RESULTS: The mean age of the 63 patients under study was 75 years. On admission the mean ejection fraction was 33% (95% CI: 31-35) and the BNP hormone median value was 726.5 pg/ml (range: 217 to 2283 pg/ml); 65% of the patients used NIV. The median value of MIP measured after clinical stabilization was -52.7 cmH2O (range: -20 to -120 cmH2O); 76% of the patients had MIP values below 70% of the predictive value. On discharge, after a median hospital stay of 11 days, the median MIP was -53.5 cmH2O (range:-20 to -150 cmH2O); 71% of the patients maintained their MIP values below 70% of the predictive value. The differences found were not statistically significant. CONCLUSION: Elderly patients admitted with AHF may present a high prevalence of RMW on admission; this condition may be maintained at similar levels on discharge in a large percentage of these patients, even after clinical stabilization of the heart condition.