This article reviews the Systemic blood pressure (BP) morphology and identifies problematic morphology and the cause of the morphology abnormality. The BP cycles is typically used to report endpoints pertaining to systole, diastole, mean blood pressure, and pulse rate (heart rate).
NOTE: Please refer to Surgical Manuals and Videos for PhysioTel, PhysioTel HD, and PhysioTel Digital Implants or watch the PhysioTel Digital Surgical Video Large Animal Left Ventricular Pressure (LVP), Blood Pressure (BP), and ECG for large animal surgeries and HD-S21 Surgical Video Rat Left Ventricular Pressure (LVP), Blood Pressure (BP), and ECG for rat surgeries. Please refer to following videos for mouse PA-C10 Surgical Video Mouse Blood Pressure, HD-X11 Surgical Video Mouse Blood Pressure and ECG, or surgical manuals HD-X Device Surgical Manual.
Typical morphology of the BP signal
Figure 1 shows a typical BP morphology. Characteristic of typical morphology in Blood Pressure is
- Systolic, diastolic, and mean pressure within normal physiological ranges
- Pulse pressure (Ponemah refers to as Pulse Height (PH)) is within expected ranges, greater than 10 mmHg for rodents and greater than 20 mmHg for large animals. Please note that this is dependent on the animal model and pressure values for the given subject.
Sudden increase/decrease in blood pressure
This is typically indicative of a clot. See Figures 2 and 3 for example. To prevent clots, please see the article Preventing Clots in the Catheter Tip.
Periodic spikes (1 Hz) on BP channel
This section only applies to PhysioTel Digital implants.
The blood pressure waveform normally looks like this :
When the battery voltage gets low (below 3V), periodic spikes will appear (one spike every second) :
The amplitude of these spikes will increase until the battery is completely depleted :
Note that these spikes can also be caused by Battery Passivation. In this case, the spikes will reduce in amplitude and finally go away as the passivation is burned off, with no user intervention required.
For more information about Battery Passivation, see the link below :