It is generally accepted that an increase in blood CO(2) increases ventilation. We also know that during carbohydrate metabolism a larger amount of CO(2) is produced than during metabolism of lipids or proteins. The aim of the present study was therefore to assess whether carbohydrate ingestion can increase CO(2) production enough to stimulate ventilation, which could in turn increase arterial oxygenation and alleviate the symptoms of hypoxia in a hypoxic environment. Fourteen subjects participated in two trials, which consisted of two normoxic and an acute hypoxic period (F(i(O(2))) = 12.86%). Following the first control normoxic period, the subjects ingested either a 10% water solution of sucrose (CHO; 4 kcal/kg body mass) or an equal volume of water (control). Hemoglobin saturation, heart rate, and ventilation parameters were monitored throughout the experiment. In contrast to the control trial, CO(2) production (V(CO(2)); L), ventilation (V; L/min), and heart rate were all significantly (p < 0.001) increased in the CHO trial during the second normoxic exposure; these parameters were also significantly elevated during the hypoxic exposure, as compared to the control trial. Carbohydrate ingestion 40 min prior to acute hypoxic exposure significantly (p < 0.001) improved hemoglobin saturation by 4%. The results suggest that ingestion of carbohydrates can improve arterial oxygenation during acute hypoxic exposure.

While there are discernible and meaningful differences between HUTT-P and HUTT-N subjects, they are not sufficient to discriminate between the two groups and predict a syncope early in the HUTT. The results might improve with a larger set of subjects; however, we can conclude that it is not likely that syncope predictions of practical value can be obtained from aggregate HRV spectral analysis and BRS values.

Higher HRV of group of neonates, who did not differ in illness severity TRIPS score from the lower HRV group, is associated with a faster and significant decrease in HR after transport and a 2- and 4-day shorter duration of mechanical ventilation and ICU treatment.

Background: Lower heart rate variability (HRV) in a newborn might represent a risk factor for unfavourable outcome, a longer recovery after illness, and a sudden infant death. Our aim was to determine whether the newborn's sleeping position is associated with HRV. Methods: We performed a prospective clinical study in 46 hospitalized cardiorespiratory stable term newborns. During sleeping, we measured the parameters of HRV in four body positions (supine, supine with tilt, prone, prone with tilt). Results: The TP (total power spectral density) was significantly higher when lying supine in comparison to prone (p = 0,048) and to prone with tilt (p = 0,046). The HF (high frequency of power spectral density) in the supine position without tilt tended to be higher compared to prone without tilt (p > 0,05). The LF (low frequency power) was significantly higher when lying supine compared to prone, both without tilt (p = 0,018). TP and HF showed a positive correlation with gestational but not postmenstrual age (p = 0.044 and p = 0.036, respectively). Conclusions: In term newborns, sleeping position is associated with HRV. Higher TP and HF were found in the supine position, which might reflect better ANS stability. Gestational age positively correlated with TP and HF power, but only in supine position.

Background : Lower heart rate variability (HRV) in a newborn might represent a risk factor for unfavourable outcome, a longer recovery after illness, and a sudden infant death. Our aim was to determine whether the newborn’s sleeping position is associated with HRV. Methods : We performed a prospective clinical study in 46 hospitalized cardiorespiratory stable term newborns. During sleeping, we measured the parameters of HRV in four body positions (supine, supine with tilt, prone, prone with tilt). Results : The TP (total power spectral density) was significantly higher when lying supine in comparison to prone (p = 0,048) and to prone with tilt (p = 0,046). The HF (high frequency of power spectral density) in the supine position without tilt tended to be higher compared to prone without tilt (p > 0,05). The LF (low frequency power) was significantly higher when lying supine compared to prone, both without tilt (p = 0,018). TP and HF showed a positive correlation with gestational age (p = 0.044 and p = 0.036, respectively). Conclusions : In term newborns, sleeping position is associated with HRV. Higher TP and HF were found in the supine position, which might reflect better ANS stability. Gestational age positively correlated with TP and HF power, but only in supine position.