What is the most common reason for changes in IV flow rates?

The most common reason for changes in IV flow rates is often attributed to physical obstruction in the IV line. This obstruction can result from various factors, including kinks in the tubing, clotted blood at the catheter tip, or a malfunctioning pump. When there is an obstruction, the volume of fluid that can be delivered to the patient decreases, which directly affects the flow rate.

In contrast, although changes in a patient's blood pressure, the type of fluid being administered, and ambient temperature can also influence IV flow rates, they are not as frequent or direct causes compared to physical obstructions. Blood pressure mainly affects the need for fluid resuscitation rather than the flow rate itself. The characteristics of the fluids (like viscosity) do influence flow to some degree, but they are generally consistent once fluid therapy is initiated. Ambient temperature may affect the viscosity of the fluid slightly, but it is less impactful than mechanical obstructions. Thus, physical obstruction in the line is the most common and immediate factor causing changes in IV flow rates.