Urinary bladder blood flow changes during the micturition cycle in a conscious pig model

Area of Science:

• Urology
• Physiology
• Medical Engineering

Background:

• Simultaneous measurement of cystometric, cardiovascular, and vesical blood flow parameters is crucial for understanding bladder function.
• Existing methods may not accurately capture dynamic changes in bladder blood flow during the micturition cycle.

Purpose of the Study:

• To develop and validate a conscious pig model for simultaneous measurement of urodynamic and cardiovascular parameters alongside vesical blood flow.
• To investigate changes in urinary bladder blood flow throughout the micturition cycle using this novel model.

Main Methods:

• Seven female pigs underwent chronic implantation of vascular access, urodynamic catheters, and an intramural laser Doppler probe.
• Conscious urodynamic studies were performed, simultaneously recording cardiovascular, urodynamic, and vesical blood flow data.

Main Results:

• The developed model demonstrated both compliant and low-compliance bladder behaviors.
• Vesical blood flow decreased to 38% during voiding and progressively fell to 45% during low-compliance filling.
• An inverse relationship between intravesical pressure and bladder blood flow was consistently observed.

Conclusions:

• The conscious pig model is suitable for studying bladder physiology, yielding reproducible results.
• Intraluminal bladder pressure is the primary determinant of blood flow within the bladder wall.
• Bladder blood flow adapts during normal filling but decreases as intravesical pressure rises.