Volume-targeted mask ventilation during simulated neonatal resuscitation

Positive Pressure Ventilation in Preterm Infants in the Delivery Room: A Review of Current Practices, Challenges, and Emerging Technologies

BACKGROUND

A major proportion of preterm neonates require positive pressure ventilation (PPV) immediately after delivery. PPV may be administered through a face mask (FM) or nasal prongs. Current literature indicates that either of these are associated with similar outcomes.

SUMMARY

Nonetheless, FM remains the most utilized and the best choice. However, most available FM sizes are too large for extremely preterm infants, which leads to mask leak and ineffective PPV. Challenges to providing effective PPV include poor respiratory drive, complaint chest wall, weak thoracic muscle, delayed liquid clearance, and surfactant deficiency in preterm infants. Mask leak, airway obstruction, poor technique, and inappropriate size are correctable causes of ineffective PPV. Visual assessment of chest rise is often used to assess the efficacy of PPV. However, its accuracy is debatable. Though end tidal CO2 may adjudge the effectiveness of PPV, clinical studies are limited. The compliance of a preterm lung is highly dynamic. The inflating pressure set on T-piece is constant throughout the resuscitation, but the lung volume and dynamics changes with every breath. This leads to huge fluctuations of tidal volume delivery and can trigger inflammatory cascade in preterm infants leading to brain and lung injury. Respiratory function monitoring in the delivery room has potential for guiding and optimizing delivery room resuscitation. This is, however, limited by high costs, complex information that is difficult to interpret during resuscitation, and absence of clinical trials.

KEY MESSAGES

This review summarizes the existing literature on PPV in preterm infants, the various aspects related to it such as the pathophysiology, interfaces, devices utilized to deliver it, appropriate technique, emerging technologies, and future directions.

Comparison of positive pressure ventilation devices during compliance changes in a neonatal ovine model

BACKGROUND

To compare tidal volume (VT) delivery with compliance at 0.5 and 1.5 mL/cmH2O using four different ventilation (PPV) devices (i.e., self-inflating bag (SIB), T-Piece resuscitator, Next Step (a novel Neonatal Resuscitator), and Fabian ventilator (conventional neonatal ventilator) using a neonatal piglet model.

DESIGN/METHODS

Randomized experimental animal study using 10 mixed-breed neonatal piglets (1-3 days; 1.8-2.4 kg). Piglets were anesthetized, intubated, instrumented, and randomized to receive positive pressure ventilation (PPV) for one minute with a SIB with or without a respiratory function monitor (RFM), T-Piece resuscitator with or without an RFM, Next Step, and Fabian Ventilator with both compliance levels. Compliance changes were achieved by placing a wrap around the piglets' chest and tightened it. Our primary outcome was targeted VT delivery of 5 mL/kg at 0.5 and 1.5 mL/cmH2O lung compliance.

RESULTS

At 0.5 mL/cmH2O compliance, the mean(SD) expired VT with the Next Step was 5.1(0.2) mL/kg compared to the Fabian 4.8(0.5) mL/kg, SIB 8.9(3.6) mL/kg, SIB + RFM 4.5(1.8) mL/kg, T-Piece 7.4(4.3) mL/kg, and T-Piece+RFM 6.4(3.1) mL/kg. At 1.5 mL/cmH2O compliance, the mean(SD) expired VT with the Next Step was 5.2(0.6) mL/kg compared to the Fabian 4.4(0.7) mL/kg, SIB 12.1(5.3) mL/kg, SIB + RFM 9.4(3.9) mL/kg, T-Piece 8.6(1.5) mL/kg, and T-Piece+RFM 6.5 (1.6) mL/kg.

CONCLUSION

The Next Step provides consistent VT during PPV, which is comparable to a mechanical ventilator.

IMPACT

Current guidelines recommend fixed peak inflation pressure in resuscitation, linked to lung and brain injury. The Next Step Neonatal Resuscitator, a cost-effective device, offers volume-targeted positive pressure ventilation with consistent tidal volumes. With two different compliances, the Next Step Neonatal Resuscitator delivered a consistent tidal volume which was similar to a mechanical ventilator. The Next Step Neonatal Resuscitator outperformed self-inflating bags and T-Pieces in delivering targeted tidal volumes. The Next Step Neonatal Resuscitator could be an alternative ventilation device for neonatal resuscitation.