A pt. developed resp. distress and hypoxemia after central venous catheterization through int. jugular vein, reason for this is -

Ans is 'a' ie. Pneumothorax Sabiston writes ? "Central venous cannulation is indicated for monitoring of central venous pressure, chronic intravenous therapy such as hyperalimentation, inseion of transvenous electrodes, and obtaining venous access in pts. with difficult peripheral venous access. The internal jugular and subclan veins are most commonly cannulated. Potential complications include haematoma, neurological injury, pneumothorax or haemothorax, arrythmias, cardiac rupture and thrombosis."