In vivo effect of pneumonia on surfactant disaturated-phosphatidylcholine kinetics in newborn infants

Bacterial pneumonia in newborns often leads to surfactant deficiency or dysfunction, as surfactant is inactivated or its production/turnover impaired. No data are available in vivo in humans on the mechanism of surfactant depletion in neonatal pneumonia. We studied the kinetics of surfactant's major component, disaturated-phosphatidylcholine (DSPC), in neonatal pneumonia, and we compared our findings with those obtained from control newborn lungs

Does whole-body hypothermia in neonates with hypoxic-ischemic encephalopathy affect surfactant disaturated- phosphatidylcholine kinetics?

none8noBACKGROUND: It is unknown whether Whole-Body Hypothermia (WBH) affects pulmonary function. In vitro studies, at relatively low temperatures, suggest that hypothermia may induce significant changes to the surfactant composition. The effect of WBH on surfactant kinetics in newborn infants is unknown. We studied in vivo kinetics of disaturated-phosphatidylcholine (DSPC) in asphyxiated newborns during WBH and in normothermic controls (NTC) with no or mild asphyxia. Both groups presented no clinically apparent lung disease. METHODS: Twenty-seven term or near term newborns requiring mechanical ventilation were studied (GA 38.6±2.2 wks). Fifteen during WBH and twelve NTC. All infants received an intra-tracheal dose of 13C labelled DSPC and tracheal aspirate were performed. DSPC amount, DSPC half-life (HL) and pool size (PS) were calculated. RESULTS: DSPC amount in tracheal aspirates was 0.42 [0.22-0.54] and 0.36 [0.10-0.58] mg/ml in WBH and NTC respectively (p = 0.578). DSPC HL was 24.9 [15.7-52.5] and 25.3 [15.8-59.3] h (p = 0.733) and DSPC PS was 53.2 [29.4-91.6] and 40.2 [29.8-64.6] mg/kg (p = 0.598) in WBH and NTC respectively. CONCLUSIONS: WBH does not alter DSPC HL and PS in newborn infants with no clinical apparent lung disease.Nespeca, Matteo; Giorgetti, Chiara; Nobile, Stefano; Ferrini, Ilaria; Simonato, Manuela; Verlato, Giovanna; Cogo, Paola; Carnielli, VirgilioNespeca, Matteo; Giorgetti, Chiara; Nobile, Stefano; Ferrini, Ilaria; Simonato, Manuela; Verlato, Giovanna; Cogo, Paola; Carnielli, Virgili

Does whole-body hypothermia in neonates with hypoxic-ischemic encephalopathy affect surfactant disaturated- phosphatidylcholine kinetics?

Background It is unknown whether Whole-Body Hypothermia (WBH) affects pulmonary function. In vitro studies, at relatively low temperatures, suggest that hypothermia may induce significant changes to the surfactant composition. The effect of WBH on surfactant kinetics in newborn infants is unknown. We studied in vivo kinetics of disaturated-phosphatidylcholine (DSPC) in asphyxiated newborns during WBH and in normothermic controls (NTC) with no or mild asphyxia. Both groups presented no clinically apparent lung disease. Methods Twenty-seven term or near term newborns requiring mechanical ventilation were studied (GA 38.6\ub12.2 wks). Fifteen during WBH and twelve NTC. All infants received an intra-tracheal dose of 13C labelled DSPC and tracheal aspirate were performed. DSPC amount, DSPC half-life (HL) and pool size (PS) were calculated. Results DSPC amount in tracheal aspirates was 0.42 [0.22\u20130.54] and 0.36 [0.10\u20130.58] mg/ml in WBH and NTC respectively (p = 0.578). DSPC HL was 24.9 [15.7\u201352.5] and 25.3 [15.8\u2013 59.3] h (p = 0.733) and DSPC PS was 53.2 [29.4\u201391.6] and 40.2 [29.8\u201364.6] mg/kg (p = 0.598) in WBH and NTC respectively. Conclusions WBH does not alter DSPC HL and PS in newborn infants with no clinical apparent lung disease

Does whole-body hypothermia in neonates with hypoxic-ischemic encephalopathy affect surfactant disaturated- phosphatidylcholine kinetics?

Background It is unknown whether Whole-Body Hypothermia (WBH) affects pulmonary function. In vitro studies, at relatively low temperatures, suggest that hypothermia may induce significant changes to the surfactant composition. The effect of WBH on surfactant kinetics in newborn infants is unknown. We studied in vivo kinetics of disaturated-phosphatidylcholine (DSPC) in asphyxiated newborns during WBH and in normothermic controls (NTC) with no or mild asphyxia. Both groups presented no clinically apparent lung disease. Methods Twenty-seven term or near term newborns requiring mechanical ventilation were studied (GA 38.6±2.2 wks). Fifteen during WBH and twelve NTC. All infants received an intra-tracheal dose of 13C labelled DSPC and tracheal aspirate were performed. DSPC amount, DSPC half-life (HL) and pool size (PS) were calculated. Results DSPC amount in tracheal aspirates was 0.42 [0.22-0.54] and 0.36 [0.10-0.58] mg/ml in WBH and NTC respectively (p = 0.578). DSPC HL was 24.9 [15.7-52.5] and 25.3 [15.8- 59.3] h (p = 0.733) and DSPC PS was 53.2 [29.4-91.6] and 40.2 [29.8-64.6] mg/kg (p = 0.598) in WBH and NTC respectively. Conclusions WBH does not alter DSPC HL and PS in newborn infants with no clinical apparent lung disease

Ventilatory parameters of study patients.

<p>FiO₂, fraction of inspired oxygen; MAP, mean airway pressure; OI, oxygenation index; PaO2, arterial pO2; NS, not significant, <i>P</i> < 0.05 is considered as statistically significant.</p

Clinical characteristics of study patients.

<p>NS: not significant, <i>P</i> < 0.05 was considered as statistically significant.</p

DSPC half-life and pool size in asphyxiated newborns under Whole-Body Hypothermia and in normothermic controls.

<p>Panel a: Median DSPC HL in the two groups, expressed in hours (h). DSPC HL was not significantly different in the WBH group compared with NTC group. Panel b: Median DSPC PS in the two groups, expressed in mg/kg. DSPC PS was not significantly different in WBH group compared to NTC group. Data were expressed as median (IQR).</p

DSPC half-life (HL) and pool size (PS) in the two study groups.

<p>Panel A: Median DSPC HL in the two groups. DSPC HL was significantly shorter in newborns with pneumonia (light grey box) compared with newborns with no lung disease (grey box). Data are expressed as median (IQR). Panel B: Median DSPC PS in the two groups. DSPC PS was significantly lower in newborns with pneumonia (light grey box) compared with newborns with no lung disease (grey box). Data are expressed as median (IQR).</p

Clinical characteristics of study patients.

<p>Clinical characteristics of study patients.</p