A system to detect occlusion of an intravenous catheter may include a housing, which may include a distal end configured to couple to a proximal end of a catheter adapter and an inner lumen forming a fluid pathway. The system may also include a wave transmitter, a transducer disposed within the fluid pathway, a processor coupled to the transducer, and an indicator unit coupled to the processor. The wave transmitter may transmit energy waves along a length of an intravenous catheter of the catheter adapter. The processor may receive an electrical signal corresponding to the portion of the energy waves that are reflected back from the intravenous catheter and may determine a difference between the electrical signal and a baseline signal. In response to the difference between the electrical signal and the baseline signal meeting a threshold value, the indicator unit may alert a user.