What is a common cause of bradycardia in a newborn during resuscitation?

Bradycardia in a newborn during resuscitation is commonly linked to asphyxia or inadequate ventilation because these conditions severely impact oxygen supply to the developing heart and body. When a newborn experiences asphyxia, often due to airway obstruction or ineffective ventilation during resuscitation efforts, the heart may respond by slowing its rate. This is a protective physiological response to anoxic stress, as the body tries to conserve oxygen for vital organs.

Inadequate ventilation results in increased carbon dioxide levels and decreased oxygen levels in the bloodstream, leading to respiratory and metabolic acidosis, which can further contribute to bradycardia. Thus, effective ventilation is crucial in maintaining an adequate heart rate during resuscitation. The other options may contribute to bradycardia, but asphyxia and inadequate ventilation are most directly related to the immediate circumstances encountered during resuscitation, making them a leading cause of bradycardia in this context.