Measurement of Mean Arterial Pressure by Carotid Artery Cannulation in Isoflurane Anesthetized Wistar Rats

Abstract

Rats in particular are a widely-used model for experimental studies (Ordodi et al., 2004). Blood pressure measurement is one of the fastest and most informative means of assessing cardiovascular function and provides an accurate indication of drug effects, surgical events and hemodynamic trends (Tranquilli et al., 2007). A close monitoring of the animals during any experiment is important to detect early imbalances and prevent any changes that could compromise the results. Experimental surgery on small lab animals, especially rats, it's a widely used model. In order to perform surgery, anaesthesia must be used and it usually causes a slowdown of the respiration that induces metabolic imbalances. It could cause cardiovascular collapse and death if left unbalanced. A close monitoring of the respiration, ECG, blood pressure is necessary during the experiment (Ordodi et al., 2004). Because it may not be always available or the prohibitive cost of the special equipment used to perform these tasks, we adapted a simple device and method to record the mean arterial pressure (MAP) in rats by carotid catheterisation and the results obtained were sustainable. In our experiment, we present a simple method to record mean arterial pressure by carotid cannulation in anesthetised rats which can be easily performed and the materials needed are no others that the one used for other species.A number of 10 rats were anesthetised with isoflurane and were surgically prepared in the ventral cervical area. The carotid artery was dissected and exposed by surgical techniques; an intravenous cannula was placed and connected to a transducer. This transforms the pressure from the blood flow in an electronic wave which is registered on the Dräger Infinity Delta monitor.

Comparison among different methods for blood pressure monitoring in rats: literature review

“…Injectable intra-muscular or intra-peritoneal anesthetic protocols can be used like urethan/ketamin folwed by xylazine/pentobarbital, or just xylazine+ketamine and also mix of injectable and inhalation anesthetic can be used. Products like Isoflurane in combination with tramadol or other analgesics can also be used (Bogdan et al, 2017;Kramer and Kinter, 2003;Meredith, 2015;Ordodi et al, 2005;Parasuraman and Raveendran, 2012). The protocol must be performed in a surgery room or in an aseptic experimental room, a surgery warm table is required and a surgical lamp for a proper view during surgery.…”