Physiological monitoring is an important aspect of mouse imaging, both to ensure animal health during the imaging experiments, as well as to characterize and control physiology during the procedure. Common needs for mouse physiological monitoring include body temperature, respiration and cardiac cycle. Robust measurement of these parameters is typically challenging in the mouse, mainly due to the animal’s size. Fortunately, there are now a variety of commercially available sensors and completely integrated systems that facilitate this. Many of these are compatible with multiple imaging modalities across major manufacturers, and incorporate software to record multiple physiological parameters in parallel. Software can also be used to provide signals that can be sent to the scanners to trigger image data acquisition with the respiratory and/or cardiac cycles (termed image ‘gating’). 
Natural electrical impulses coordinate contractions of the different parts of the heart to keep blood flowing the way it should. An ECG records these impulses to show how fast the heart is beating, the rhythm of the heart beats (steady or irregular), and the strength and timing of the electrical impulses as they move through the different parts of the heart. Changes in an ECG can be a sign of many heart-related conditions.  Below is shown a zoomed ECG signal of a mouse acquired using our small animal monitoring platform. More details here.
Oxygen Saturation (SpO2)
Oxygen saturation has become a standard in mouse monitoring. The ratio between oxy and deoxy-hemoglobin is calculated using the difference of absorption of light at different wavelengths. The setup is easy, inexpensive and non invasive. The results are reliable and animal well-being can be verified in real-time. For example, the hypoxia can be detected with very short response time. The figure below demonstrates that the effect of a lower oxygen concentration (10% O2) affects the oxygen saturation and heart rate acquired with our SpO2 & Heart Rate Monitor.
Blood Pressure (BP)
The most widely used sensor device in animal studies has been the saline-filled catheter, whose distal end is connected to a calibrated pressure transducer. For long-term or continuous measurements, the external portion of the catheter can be housed in a protective tether, and connected to a swivel to allow free movement of the animal. The advantages of this method include: (1) the materials are inexpensive; (2) precise calibration is easy for static (i.e., mean) pressures; and (3) in the case of a swivel and tether system, continuous long-term recordings can be obtained under conditions of relatively low stress for many weeks (e.g., for 6 weeks or more, Wang, Tempini, Schnyder, & Montani, 1999). 
Exhaled CO2 (EtCO2)
In the past few decades, assessment of exhaled CO2 in both intubated and non-intubated patients has evolved into an essential component in many aspects of patient monitoring. Besides the basic assessment of ventilation, exhaled CO2 monitoring can provide valuable patient safety information and critical physiological data in regards to the ventilation and perfusion matching in the lungs, cardiac output, and metabolic rate. Despite these important clinical monitoring benefits and widespread availability, exhaled CO2 monitoring is often underutilized. 
- Deanne Lister, … Patrick McConville, in The Laboratory Mouse (Second Edition), 2012
- Electrocardiogram. Johns Hopkins Medicine. (n.d.). Retrieved here on February 15, 2022
Direct and Indirect Methods used to study arterial blood pressure. Journal of Pharmacological and toxicological methods, 44(2), 361–373: 10.1016/S1056-8719(00)00126-X. Sci. (n.d.).
Siobal, M. S. (2016). Monitoring exhaled carbon dioxide. Respiratory Care, 61(10), 1397–1416. https://doi.org/10.4187/respcare.0491.
Our team made sure that the workflow is the simplest. All our monitoring devices transfer data over a wireless tablet. Data can be transferred to a computer using a standard cloud service or via a usb cable. Data can be opened trough Matlab and Excel for further processing and analysis. Simple GUI let you produce article-ready figures with any physiological signal.
Labeo Technologies Monitoring Devices
Our line of monitoring devices offers flexible solutions for precise monitoring. Our complete physiological monitoring system is the key solution to intensively monitor many physiological parameters and saving it for further processing. It also offers compatibility with any imaging system for “Gating”. Our SpO2 & Heart Rate Monitor, on the other hand, offers a lower cost alternative to monitor heart rate and oxygen saturation. Both devices offer Bluetooth connection with an Android tablet, data saving and playback.