Cardiac autonomic modulation assessed by heart rate variability in children with asthma.

OBJECTIVE: To assess cardiac autonomic modulation, measured by short-term frequency domain analysis of heart rate variability (HRV), in children with asthma. METHODS: We conducted an observational study at a tertiary care teaching hospital. The sample consisted of 119 children aged 7 to 15 years with asthma and 56 age-matched healthy controls. Frequency domain HRV measures included low-frequency (LF; 0.04-0.15 Hz), high-frequency (HF; 0.15-0.4 Hz), and LF/HF ratio. The LF and HF components were expressed in both absolute values of power (ms2 ) and in normalized units (nu). RESULTS: Compared with healthy controls, asthmatic children had significantly higher value of HF (nu) (mean ± standard deviation: 45.9 ± 14.6 vs 40.7 ± 13.6; P = .02), and lower values of LF (nu) (54.1 ± 14.6 vs 59.3 ± 13.6; P = .02) and LF/HF ratio (median, interquartile range: 1.12, 0.82-1.88 vs 1.59, 1.02-2.08; P = .03). We did not find significant differences between children with persistent and intermittent asthma, and between children with well-controlled and partially-controlled or uncontrolled asthma, in terms of HRV measures. CONCLUSIONS: Children with stable chronic asthma may have a cardiac autonomic imbalance with a possible enhanced parasympathetic modulation, as assessed by short-term frequency domain analysis of HRV. Neither asthma severity nor asthma control was significantly associated with HRV measures, but the study did not have enough power to draw a firm conclusion on this point.

Impact of hypertonic saline on hospitalization rate in infants with acute bronchiolitis: A meta-analysis.

AIM: This meta-analysis aimed to assess the efficacy of nebulized hypertonic saline (HS) on the rate of hospitalization in infants with acute bronchiolitis in the Emergency Department (ED) setting. METHOD: We searched PubMed, Virtual Health Library-BVS and Cochrane CENTRAL from inception until January 31, 2018. We selected randomized trials that compared nebulized HS with normal saline (NS) or standard care in children up to 24 months of age with acute bronchiolitis in the ED setting. We conducted random-effects meta-analyses to estimate the risk ratio (RR) and 95% confidence interval (CI). RESULTS: A total of 293 records were screened and 8 trials involving 1708 patients were included. The meta-analysis showed a 16% reduction in the risk of hospitalization among patients treated with HS compared to NS (risk ratio [RR]: 0.84, 95% confidence interval [CI]: 0.71-0.98, P = 0.03). A significant effect of HS in reducing the risk of hospitalization was found only in the subgroup analyses of trials in which HS was mixed with bronchodilators, multiple doses (≥3) were given, and risk of bias was low. CONCLUSIONS: Nebulized hypertonic saline may potentially reduce the risk of hospitalization in infants with acute bronchiolitis in the ED setting. Quality of evidence is moderate due to substantial clinical heterogeneity between studies and large multicenter trials are still warranted.