What are the methods used to measure blood pressure is directly?

Catheterization method involving the sensing of blood pressure through a liquid column. In this method the transducers is external to the body and blood pressure is transmitted through a saline solution column in a catheter to this transducers. This method also involves the placement of transducers through a catheter at the actual site of measurement in the blood stream.

Percutaneous methods in which the blood pressure is sensed in the vessel just under the skin by the use of a needle or catheter. Implantation technique in which the transducer is more permanently placed in the blood vessel.