Using airway resistance measurement to determine when to switch ventilator modes in congenital diaphragmatic hernia: a case report

Clinical Research on Modified Postural Drainage for Secretion Clearance in Infants with Wheezing Bronchitis

BACKGROUND

Wheezing bronchitis is common in infants and can lead to complications if not properly managed. Postural drainage is a standard technique for secretion clearance, but the optimal protocol remains debated.

AIMS

This study aims to assess the clinical efficacy and safety of a modified postural drainage nursing protocol for secretion clearance in infants with wheezing bronchitis.

METHODS

This prospective study included 104 infants (six months to three years) hospitalized with wheezing bronchitis between January 2023 and May 2024. Participants were randomly divided into two groups: observation (N = 52, modified protocol) and control (N = 52, conventional protocol). The modified protocol optimized drainage frequency, standardized position transitions, regulated rest periods, and included respiratory training. Key outcomes included the Modified Respiratory Sound Score (MRSS), symptom resolution, radiological improvements, and hospital stay duration.

RESULTS

On Day four, MRSSs were significantly lower in the observation group (2.2 ± 0.4) compared to the control group (3.5 ± 0.5, P < 0.001). Rhonchi, wheezing, and cough resolved more quickly in the observation group (P < 0.001 for all). Chest X-ray absorption rates were higher (88.5% vs. 80.8%, P = 0.035), and hospital stays were shorter (6.5 ± 1.2 vs. 8.5 ± 1.5 days, P < 0.001). Adverse event rates were similar (21.2% vs. 25.0%, P = 0.641).

CONCLUSION

The modified protocol significantly improved secretion clearance, accelerated symptom resolution, and reduced hospital stays without compromising safety in infants with wheezing bronchitis.

Respiratory function testing for guiding ventilator mode conversion in congenital diaphragmatic hernia

INTRODUCTION

For patients with a congenital diaphragmatic hernia, conventional mechanical ventilation (CMV) and high-frequency oscillatory ventilation (HFOV) are used in initial ventilatory management. HFOV has recently been recommended as a rescue therapy; however, we use HFOV for initial ventilation management, with a preoperative challenge test for CMV conversion and respiratory function testing at the time of CMV conversion. We aimed to compare patient characteristics between CMV conversion- and HFOV-preferred treatment groups.

METHODS

Ventilator settings and blood gases were retrospectively evaluated pre- and post-CMV conversion, and respiratory function tests for compliance of the respiratory system (Crs) and for resistance of the respiratory system (Rrs) were performed during the trial to CMV conversion.

RESULTS

No differences were observed between the CMV conversion- and HFOV-preferred groups regarding gestational age, birth weight, and observed/expected lung area-to-head circumference ratios. The median Crs (ml/cmH2 O/kg) and Rrs (cmH2 O･kg/L/s) in the CMV conversion- and HFOV-preferred groups was 0.42 versus 0.53 (p = .44) and 467 versus 327 (p = .045), respectively. The pre and posttrial amount of change in blood gas levels and ventilator parameters in the CMV conversion- and HFOV-preferred groups were as follows: mean airway pressure, -2.0 versus 0 cmH2 O; partial pressure of carbon dioxide, 6.1 versus 2.9 Torr; alveolar-arterial oxygen difference, -39.5 versus -50 Torr; and oxygenation index, -1.0 versus -0.6; respectively.

CONCLUSION

Respiratory function tests were useful in tailoring ventilator settings. Patients with high Rrs values responded better to CMV conversion.

Right to left ventricular volume ratio is associated with mortality in congenital diaphragmatic hernia

BACKGROUND

Congenital diaphragmatic hernia (CDH) is associated with high neonatal mortality. We performed this study to test the hypothesis that left ventricular (LV) and right ventricular (RV) volumes assessed by three-dimensional echocardiography may be associated with mortality in CDH.

METHODS

This study was a single-center retrospective cohort study involving 35 infants with CDH. RV and LV end-diastolic volume (RVEDV and LVEDV, respectively) were measured by three-dimensional echocardiography and were corrected by birth body weight (BBW) on day 1. RVEDV/BBW, LVEDV/BBW, and LVEDV/RVEDV were compared between CDH survivors and non-survivors. Receiver-operating characteristic curve analysis was performed to assess the predictive ability for mortality of the echocardiographic parameters.

RESULTS

Comparing CDH non-survivors (n = 6) with survivors (n = 29), respectively, RVEDV/BBW was significantly larger (2.54 ± 0.33 vs 1.86 ± 0.35 ml/kg; P < 0.01), LVEDV/BBW was significantly smaller (0.86 ± 0.21 vs 1.22 ± 0.33 ml/kg; P < 0.001), and LVEDV/RVEDV was significantly lower (0.34 ± 0.06 vs 0.66 ± 0.18; P < 0.001). The area under the curve for LVEDV/RVEDV was the largest (0.98).

CONCLUSIONS

Three-dimensional echocardiographic volume imbalance between the RV and LV was remarkable in CDH non-survivors. The LVEDV/RVEDV ratio may be associated with mortality in CDH.

IMPACT

Mortality with congenital diaphragmatic hernia (CDH) is high, and evaluating left and right ventricular structures and functions may be helpful in assessing the prognosis. Three-dimensional (3D) echocardiography indicated that the left ventricular end-diastolic volume/right ventricular end-diastolic volume ratio within 24 h after birth was associated with mortality in CDH infants. The usefulness of this ratio should be validated in prospective multicenter studies involving larger numbers of patients.