Final answer:
When positive-pressure ventilation is given to an apneic newborn and there's no chest movement with a heart rate of 40 BPM, first check and correct the airway, ensuring the endotracheal tube position is correct. If there's no improvement, start chest compressions while continuing PPV.
Step-by-step explanation:
If you have started positive pressure ventilation (PPV) for an apneic newborn and the heart rate remains at 40 BPM without improvement, and there is no observable chest movement, the next immediate action should be to evaluate the airway to ensure proper ventilation. The lack of chest movement suggests that air is not reaching the infant's lungs. Therefore, you should first reposition the airway to maintain a patent airway and, if an endotracheal tube is in place, check the placement. If after these measures there is still no chest movement and the heart rate does not increase, begin chest compressions in conjunction with PPV by following the guidelines for neonatal resuscitation which state that chest compressions should be initiated when the heart rate is below 60 BPM after 30 seconds of effective positive-pressure ventilation.
It is important to remember that administering epinephrine and additional resuscitation measures might be considered if there's no response to ventilation and chest compressions. Nonetheless, ensuring that breaths are effective is the priority, as oxygenation is critical for the heart rate to improve.