Complex sentence: After each use, a heparin lock is made by injecting a small amount of heparinized saline (an anticoagulant) into the device, preventing development of clots within the port or catheter.
Split into simpler sentences: After each use, a heparin lock is made by injecting a small amount of heparinized saline (an anticoagulant) into the device. This prevents development of clots within the port or catheter.