Which of the following is a common indicator of effective mechanical ventilation?

In mechanical ventilation, effective ventilation is often assessed by the adequacy of gas exchange and the overall stability of the patient’s respiratory status. An increased tidal volume, paired with stable blood gas values, is a reliable indicator of effective mechanical ventilation. Tidal volume refers to the amount of air delivered to the lungs with each breath, and an increase suggests that the ventilatory support is appropriately meeting the patient's respiratory needs.

Stable blood gases indicate that the patient is maintaining proper acid-base balance, which is crucial for physiological function. When tidal volume is increased, it often leads to improved ventilation and more effective clearing of carbon dioxide, resulting in normalized blood gas levels. This correlation highlights the efficacy of the mechanical ventilation in supporting the patient's respiratory demands, making this the correct choice.

Other options present conditions that can be associated with ineffective ventilation or signs of distress. For instance, a decreased respiratory rate with signs of distress might indicate hypoventilation or inadequate oxygenation. The presence of dead space without measurable impact could imply that ventilation is not effectively contributing to gas exchange. Lastly, the absence of chest rise and fall suggests inadequate ventilation. Therefore, the relationship between increased tidal volume and stable blood gases clearly identifies effectiveness in mechanical ventilation, marking this option as correct.