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

Blood pressure is a cardinal vital sign that gives important information about the cardiovascular function and about hemodynamic trends during anaesthesia, in critical ill patients and during experimental procedures (Rehman and Nelson, 2018). Arterial blood pressure can be evaluated by direct technique (arterial catheter) or indirect technique (Doppler or oscillometry). Direct measurement is gold standard for blood pressure measurement, giving accurate beat-to-beat information and also allow collection of blood samples. However, it is more invasive and requires equipment for monitoring and experience to place the arterial catheter (Araghi et al., 2006; Ward and Langton, 2007; Wingfield and Raffe, 2002). Given its importance in directing care, it is essential to measure blood pressure accurately and consistently.The aim of this article is to present all technique found in literature, with its advantages and disadvantages, with the errors that may occur so that the researchers can have a better knowledge before choosing their technique. For this study we took into consideration articles from literature and speciality books from which we extracted the information reliable for the study. Experimental studies on small laboratory animals, particularly rats are widely used as a model. Three methods are used for recording the blood pressure in rats: tail cuff (indirect technique), intra-arterial catheters (direct technique), and radio telemetry. Each technique has its advantages and disadvantages and each of it may lead to erroneous data if they are improperly performed. The vast ranges of these errors highlight the importance of adhering to appropriate technique when measuring blood pressure.