Finding on a chest radiograph: A dangerous complication of subclavian vein cannulation

Cannulation of the subclavian vein has its inherent risks. Post procedure chest radiograph is one of the investigations done to rule out immediate complications. Unless the clinician is aware as to what to look for in the radiograph, some of the dangerous complications can be overlooked. Accidental subclavian artery cannulation is identified immediately by color and jet of the blood. Also the position of the catheter tip has to be confirmed by obtaining the arterial pressure tracing using a pressure transducer. Non availability of Doppler ultrasound and pressure transducer are limiting factors for immediate confirmation of proper catheter placement. Also, in patients with severe hypotension and reduced oxygen content of blood, accidental arterial puncture may not show the characteristic bright red pulsatile back flow of arterial blood. In these situations radiography can be used as a diagnostic tool to rule out subclavian artery cannulation.