Which physiological effect is NOT associated with mechanical ventilation?

Mechanical ventilation is a critical intervention used in various clinical settings, and it can have several physiological effects on the body. The correct choice highlights that fluid overload is not specifically associated with mechanical ventilation, while the other options are well-documented complications that can arise from this intervention.

Atelectotrauma refers to lung injury caused by repeated opening and closing of alveoli during mechanical ventilation, which can lead to damage in lung tissue. Barotrauma occurs when air pressure within the lungs exceeds the pressure outside, often due to high volumes or pressures used in mechanical ventilation, causing lung rupture or pneumothorax. Ventilator-associated pneumonia is an infection that can develop in patients who are mechanically ventilated, primarily due to bacteria entering the lungs through the endotracheal tube.

In contrast, fluid overload is generally related to the overall management of a patient's fluid balance, influenced by factors such as renal function, cardiac status, and fluid administration rather than being a direct physiological effect of mechanical ventilation itself.