👉 The checked fluid, also known as pleural fluid, is a clear, colorless liquid found in the space between the lungs and the chest wall, known as the pleural cavity. This fluid plays a crucial role in lubricating the lung movements during breathing and preventing friction between the lungs and the chest wall. It is produced by both the lung tissue and the lining of the pleural cavity (the pleura), with a balance maintained by a constant exchange between these two sources. The normal range for checked fluid is typically between 5 and 20 milliliters per kilogram of body weight, measured through a procedure called thoracentesis. Variations in this fluid's volume or characteristics can indicate underlying lung diseases such as pneumonia, heart failure, or pulmonary edema.
