Fluid question: Detecting Blood Pressure in Mice

[magic_castle32]

Need some help regarding fluid flow and pressure detection:To detect blood pressure in a mouse, we usually insert a small pipe with a refined tip into the artery that is connected to a blood pressure detector. However, the problem we have been getting is that the detected blood pressure is lower than it actually should be.

Why is this the case?

Would changing the pipe diameter, or 'pointiness' of the tip, be of help in getting a more accurate reading?

 

[Andy Resnick]

Without more information, it's hard to diagnose the problem:

How is the detector calibrated? What is your control condition? How do you know the readings are incorrect?

For example, do you also take a reading in the tail vein?

 

[magic_castle32]

Without more information, it's hard to diagnose the problem:

How is the detector calibrated? What is your control condition? How do you know the readings are incorrect?

For example, do you also take a reading in the tail vein?

The experimental setup is properly calibrated.

I just want to know if the pipe diameter, or the 'pointiness' of the tip of the pipe, could influence the pressure. Otherwise we'd have to look into other variables, or other aspects of the set-up.

 

[Andy Resnick]

It's easy to imagine viscous losses which would give low pressure readings. But again, without any information about your setup, it's hard to say anything definitive.

 

[PJC01]

I would first suggest checking the calibration of the blood pressure detector to ensure it is accurately measuring the pressure. If the detector is properly calibrated and the issue persists, then changing the pipe diameter or tip shape may help improve the accuracy of the reading.

The diameter of the pipe can affect the fluid flow and pressure within it. A larger diameter pipe would allow for a greater volume of blood to flow through, potentially resulting in a higher reading. On the other hand, a smaller diameter pipe may restrict the flow and lead to a lower reading.

Similarly, the shape of the tip can also impact the flow and pressure. A sharper, more pointed tip may allow for more precise insertion into the artery, resulting in a more accurate reading. However, it is important to consider the potential for tissue damage or obstruction with a very sharp tip.

In addition to changing the equipment, it may also be helpful to ensure proper technique and placement when inserting the pipe into the artery. The angle and depth of insertion can also affect the accuracy of the reading.

Overall, it is important to carefully consider all factors that may be contributing to the lower than expected blood pressure readings. Experimentation and careful adjustments may be necessary to find the best approach for accurately detecting blood pressure in mice.