Acute Measurements of Arterial Pressures Using Carotid Catheters
Without question, arterial pressures are most accurately measured via an indwelling catheter. For simple short-term measurements in anesthetized animals, the placement of a catheter in the carotid artery is quick, easy and reliable for the researcher with minimal surgical experience. This technique can be used in larger mammals, rats and can be adapted for use in mice. For our rodent studies (rats, mice), we prefer to use Inactin for anesthesia. As apposed to pentabarbital, it is essentially irreversable and produces a stable plane of anesthesia to produce a rock solid (almost artificially so) blood pressure. A tracing of the arterial pressure of a Dahl-Salt Hypertensive rat is shown above.
A major disadvantage this particular anesthesia is that it appears to dampen the baroreceptor reflexes. If baroreceptor function is a primary component of a study, the use of chronic indwelling arterial catheters should be considered.
The success rate for this preparation is >90% for beginners, and >99% for skilled surgeons.