Related Experiment Videos
CPAP of 4 cm H(2)O Has no short-term benefit at term in infants with BPD
Kenneth L Sandberg1, Ola Hjalmarson
1Department of Paediatrics, Queen Silvia Children's Hospital, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.
Insights
Continuous positive airway pressure (CPAP) did not improve lung function in infants with bronchopulmonary dysplasia (BPD). While functional residual capacity (FRC) increased, ventilation and gas exchange worsened, suggesting potential harm.
Area of Science:
- Neonatology
- Pediatric Pulmonology
- Respiratory Physiology
Background:
- Bronchopulmonary dysplasia (BPD) compromises lung development and function in infants at term.
- Key issues include reduced functional residual capacity (FRC) and impaired distal airway gas-mixing.
- These deficits significantly impact respiratory health in affected newborns.
Purpose of the Study:
- To evaluate the efficacy of continuous positive airway pressure (CPAP) in improving FRC, ventilation, and gas exchange in infants with BPD.
- To assess the impact of CPAP on distal airway function and overall lung mechanics.
- To determine if CPAP can ameliorate respiratory compromise in spontaneously breathing infants with BPD.
Main Methods:
- Studied 21 infants with BPD (median birth weight 0.72 kg, gestational age 26 weeks) before and after applying 4 cm H2O CPAP via facemask.
- Utilized multiple-breath nitrogen washout to measure FRC, ventilation, and gas-mixing efficiency.
- Assessed gas-mixing using moment analysis and lung clearance index; monitored transcutaneous PO2/PCO2.
Main Results:
- CPAP significantly increased FRC and moment ratios (M1/M0, M2/M0), indicating improved lung volumes and potentially better gas distribution.
- However, CPAP led to a significant decrease in transcutaneous PO2 and altered breathing patterns.
- Respiratory rate, minute ventilation, and alveolar ventilation decreased significantly, while tidal volume and dead space increased.
Conclusions:
- CPAP at 4 cm H2O did not improve ventilation, distal airway gas-mixing, or oxygenation in term infants with BPD, despite increasing FRC.
- The findings suggest CPAP may overexpand already ventilated lung regions, potentially worsening lung function in BPD.
- Further research is needed to understand the precise mechanisms and optimize respiratory support for BPD infants.
Background:
Lung development and function is compromised at term in infants with bronchopulmonary dysplasia (BPD), characterized by reduced functional residual capacity (FRC) and impaired gas-mixing efficiency in distal airways.
Objective:
To determine whether continuous positive airway pressure (CPAP) improves FRC, ventilation, distal airway function, and gas exchange in spontaneously breathing infants with BPD.
Design/Methods:
Twenty-one infants with BPD (median birth weight 0.72 kg (range 0.50-1.27) and median gestational age 26 weeks (range 23-28)) were studied before and after CPAP of 4 cm H(2)O was applied by a facemask system. A multiple-breath nitrogen washout method was used to assess FRC, ventilation, and gas-mixing efficiency. Moment analysis and lung clearance index was calculated from the nitrogen-decay curve for assessment of gas-mixing efficiency. Transcutaneous (Tc) PO(2)/PCO(2) was monitored during stable infant conditions before each washout test.
Results:
When CPAP was raised from 0 to 4 cm H(2)O, FRC increased significantly together with a significant increase in moment ratios (M(1)/M(0) and M(2)/M(0)). Tc PO(2) decreased significantly and the breathing pattern changed, with significantly reduced respiratory rate, minute ventilation, and alveolar ventilation. There was also an increase in tidal volume and dead space.
Conclusions:
CPAP of 4 cm H(2)O applied with a facemask at term to infants with BPD did not improve ventilation, gas-mixing efficiency in distal airways, or oxygenation despite an increase in FRC. We speculate that instead of promoting recruitment of unventilated lung volumes, increasing the end-expiratory pressure in infants with BPD may lead to an overexpansion of already ventilated parts of the lung, causing further compromise of lung function.
Related Concept Videos
Mechanical Ventilation III: Noninvasive Ventilation
Noninvasive Positive-Pressure Ventilation (NIPPV)
Acute Respiratory Failure-IV
Respiratory Volumes and Capacities I
Sleep Apnea
The condition is more prevalent among...
Acute Respiratory Failure-III
Cardiopulmonary Resuscitation II: ACLS Airway Management