Reference data for BabyBody-plethysmographic measurements in Chinese neonates and infants

Neonatal nutritional risk and pulmonary function

INTRODUCTION

The neonatal period is a critical initial stage of postnatal lung development and maturation. This study aimed to investigate the effects of the nutritional status on pulmonary function in late preterm and full-term neonates.

METHODS

A total of 172 newborns were included in the study. Nutritional risk screening, weight measurement, assessment of albumin and caloric intake, and a pulmonary function examination were conducted on the 7th day after birth.

RESULTS

There was a significant correlation between the nutritional risk and changes in body weight. Tidal volume (VT), minute ventilation (MV), VT per kg body weight (VT/kg), and MV per kg body weight (MV/kg) in the low nutritional risk group were significantly higher than those in the medium nutritional risk group (all P < .05). Albumin and caloric intake in the low nutritional risk group were significantly higher than those in the medium nutritional risk group (both P < .01). VT, VT/kg, MV, and MV/kg in the weight loss group were lower than those in the no weight loss group (all P < .05).

CONCLUSIONS

Changes in neonatal weight mainly affect lung volume (VT, VT/kg, MV, and MV/kg), suggesting that an improvement in the neonatal nutritional status is important for the development of lung volume.

Velocity-based target flow rate for high-flow nasal cannula oxygen therapy

BACKGROUND

The aim of this study was to assess retrospectively whether the average inspiratory flow velocity-based initial flow rate in high-flow nasal cannula (HFNC) therapy could be well tolerated and safely used for infants and children hospitalized with moderate to severe respiratory failure.

METHODS

Thirty-three patients without underlying diseases (22 males; 67%), hospitalized to receive HFNC therapy for infection-related respiratory failure, were analyzed. The median age was 2 months (interquartile range, 1 month to 1 year). Patients with dyspnea and carbon dioxide partial pressure (pCO₂ ) >50 mmHg or venous blood pH <7.320, combined with pulse oximetry arterial oxygen saturation <92%, were included. We set target flow rates calculated from the average inspiratory flow velocity, starting at the actual initial flow rates, and these were subsequently adjusted if necessary.

RESULTS

One patient could not tolerate the cannula. Of the remaining 32 patients, 81% (n = 26) had an actual initial flow rate within 1 L of the target flow rate; these patients were evaluated for changes in the fraction of inspired oxygen (FITarget flow rate tableO₂ ), pH, and pCO₂ values after 24 h. Three patients required a higher fraction of inspired oxygen, one showed a persistent pH < 7.320, and seven exhibited pCO₂ >50 mmHg. No patient required non-invasive positive-pressure ventilation, and one required intubation. Pneumothorax was not reported in any patient.

CONCLUSIONS

The average inspiratory flow velocity-based initial flow rate was well-tolerated without sedation, and there were no severe complications. Starting at this flow rate would improve the use of HFNC therapy in the pediatric ward, possibly reducing the need for more invasive modes of ventilation.

Tidal breath in healthy term newborns: An analysis from the 2nd to the 30th days of life

BACKGROUND

Few data are available concerning normative lung function parameters measured in unsedated neonates.

AIM

To evaluate lung function changes in neonates.

METHODS

In this prospective cohort study, tidal breath parameters were measured using the MasterScreen PAED system and standardized protocols. Measurements were performed on 60 (30 male) term, healthy, unsedated neonates on the postnatal 2nd and 30th days.

RESULTS

Expiratory time (TE; p < .001; Cohen's d = 0.561), exhaled volume to peak tidal expiratory flow (VPTEF; p < .001; Cohen's d = 0.789), minute ventilation (p < .001; Cohen's d = 0.926), tidal volume (VT; p < .001; Cohen's d = 1.835), expiratory flow when 75%, 50%, and 25% of tidal volume remaining in the lungs (TEF75 [p < .001; Cohen's d = 1.070], TEF50 [p < .001; Cohen's d = 0.824], TEF25 [p < .001; Cohen's d = 0.568]), and inspiratory time (Ti; p < .001; Cohen's d = 0.654) were higher on Day 30 compared to Day 2, while time to reach peak tidal expiratory flow to total expiratory time (TPTEF/TE; p = .006; Cohen's d = 0.371), the volume until peak tidal expiratory flow to total expiratory volume (VPTEF/VE; p = .001; Cohen's d = 0.447), and respiration rate (RR; p = .001; Cohen's d = 0.432) were lower, and Ti/TE was unchanged. Positive correlation was observed between length and VT (r = .347; p = .008) on Day 2 and (r = .338; p = .008) on Day 30.

CONCLUSIONS

The present study reveals the physiological changes occurring in lung functions in healthy term neonates during the neonatal period.