Spirometric reference equations for healthy children aged 6 to 11 years in Taiwan.

BACKGROUND: Spirometry is a valuable technique for evaluating pulmonary function, but there were few normative reference values for young children in Taiwan, and none for the last 10 years. The objective of our study was to establish updated reference values and equations for children aged 6-11 years in northern Taiwan. METHODS: A total of 309 healthy children (153 boys and 156 girls) were enrolled in the present study. The data of at least 3 trials for each child were collected, and the highest values analyzed. The analyzed pulmonary function parameters were focused on forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak expiratory flow rate (PEF), forced expiratory flow between 25% and 75% expired volume (FEF25-75), and the ratio of FEV1/FVC. RESULTS: The results revealed that there were mostly no significant differences between boys and girls, and the standing height (H, cm) was the factor with the highest correlation with the pulmonary function parameters. Regression equations of the major pulmonary function parameters for both boys and girls were obtained: FVC = -2.690 + 0.0330H; FEV1 = -2.559 + 0.0311H; PEF = -300.231 + 3.938H; FEF25-75 = -3.218 + 0.0425H (p < 0.001). CONCLUSION: Our study determined the updated normative values and reference equations for Chinese children aged 6-11 years living in northern Taiwan. These values can be used as normative reference values to evaluate pulmonary function in diseased children with the same ethnicity and lifestyle.

Spirometric pulmonary function parameters of healthy Chinese children aged 3-6 years in Taiwan.

Spirometry is a well-known technique for evaluating pulmonary function, but few studies have focused on preschool children. The aim of this study was to determine reference values of forced spirometric parameters in young Chinese children, aged 3-6 years, in Taiwan. Spirometric measurements were performed at day care centers by experienced pediatricians. Of 248 children without a history of chronic respiratory illness, at least two valid spirometric attempts were obtained from 214 children (109 boys and 105 girls; age: 36-83 [mean = 61] months; height: 90-131 [mean = 111] cm). Values of forced expiratory volume in 1 sec (FEV1) and 0.5 sec (FEV(0.5)), forced vital capacity (FVC), peak expiratory flow rate (PEF), forced expiratory between 25% and 75% FVC (FEF(25-75)), and forced expiratory flow rate at 25%, 50%, and 75% of FVC (FEF(25), FEF(50), and FEF(75)) were derived and analyzed. There were significant positive correlations between study parameters and body height, body weight, and age. Height was the most consistently correlated measurement in both boys and girls. Although boys tended to have higher spirometric values than girls, we found significant differences only in FVC and FEV1 between boys and girls aged 6 years. The regression equations of each parameter were obtained. In conclusion, spirometric pulmonary function tests are feasible in 3- to 6-year-old children. The obtained values and regression equations provide a reference for Chinese preschool children and may be of value in evaluating pulmonary function of children with respiratory problems in this age group.

The safety of aerodigestive tract flexible endoscopy as an outpatient procedure in young children.

BACKGROUND: Flexible endoscopy (FE) for the pediatric aerodigestive tract is an invasive and complicated procedure; therefore, it is usually performed under an inpatient setting. We investigated whether FE could be a safe procedure for outpatient young children (< 5 years old) and analyzed the findings. METHODS: Outpatient FE records were retrospectively reviewed between 1996 and 2003. Patients aged less than 5 years were enrolled and allocated to 3 age groups: group A (

Cerebral oxygenation during hypoxia and resuscitation by using near-infrared spectroscopy in newborn piglets.

BACKGROUND: Hypoxic events and cardiac arrest may cause brain damage in critical infants. This study investigated cerebral tissue oxygenation and oxygen extraction in a piglet model of hypoxic events, cardiac arrest and effects of resuscitation. METHODS: For the hypoxia experiment, anesthetized newborn piglets were randomized to a hypoxia group (n = 8) with decreasing ventilatory rate to 0, and a control group (n = 8) with no hypoxic conditions. Regional cerebral tissue oxygen saturation (rScO2, detected by near-infrared spectroscopy) and oxygen saturation were recorded every 5 minutes for 100 minutes. Fractional cerebral tissue oxygen extraction (FTOE) was calculated as (arterial oxygen saturation [SaO2] - rScO2)/SaO2. For the resuscitation experiment, animals were grouped as hypoxia-no CPR (n = 4), control-no CPR (n = 4), and control-CPR (n = 4) after cardiac arrest. Standard cardiopulmonary resuscitation (CPR) was performed on the control-CPR group and observed for 30 minutes. RESULTS: Immediate and significant changes in rScO2, and gradual changes in FTOE were observed during the hypoxia experiment. In the resuscitation experiment, no significant differences in rScO2 were found between groups. However, the highest FTOE was observed in the control-CPR group. CONCLUSION: Noninvasive monitoring of rScO2 and evaluating FTOE changes during hypoxia and resuscitation may help clinicians evaluate brain tissue oxygenation and viability.

Effects of therapeutic bronchoalveolar lavage and partial liquid ventilation on meconium-aspirated newborn piglets.

OBJECTIVE: To investigate the therapeutic effects of bronchoalveolar lavage (BAL) with either diluted surfactant (SBAL) or perfluorochemical liquid (PBAL), followed by either conventional mechanical ventilation (CMV) or partial liquid ventilation (PLV), on lung injury and proinflammatory cytokine production induced by meconium aspiration in newborn piglets. DESIGN: A prospective, randomized, experimental study. SETTING: An animal research laboratory at a medical center. SUBJECTS: Anesthetized and mechanically ventilated newborn piglets (n = 27). INTERVENTIONS: The animals were instilled with 3-5 mL/kg 25% human meconium via an endotracheal tube to induce meconium aspiration syndrome (MAS). After stabilization, animals were randomly assigned to either CMV group (no BAL) or one of the treatment groups (SBAL-CMV, SBAL-PLV, PBAL-CMV, and PBAL-PLV). MEASUREMENTS AND MAIN RESULTS: Cardiopulmonary variables were monitored, and interleukin-1beta and interleukin-6 content of the serum and lung tissue was measured. The animals without any treatment (CMV group) displayed the worst outcome; the animals in the PBAL-PLV group had the best gas exchange, lung compliance, and least pulmonary damage; and the SBAL-CMV, PBAL-CMV, and SBAL-PLV groups had intermediate effects. The serum interleukin-1beta concentration of the CMV group was significantly higher than all other groups over time (p < .05), and interleukin-6 concentration was significantly higher than the PBAL-PLV group (p < .05). The tissue interleukin-1beta and interleukin-6 contents were also highest in the CMV group and lowest in the PBAL-PLV group. CONCLUSIONS: Initial therapeutic BAL and therapeutic BAL followed by PLV with the same perfluorochemical liquid provided significant therapeutic effects in treating an animal model with severe MAS and therefore warrant consideration in cases that are intractable to other therapies.