This invention concerns urinary catheterizing and identifies a cavitation occurring at the moment of catheter removal after catheterizing drainage is completed as the source of a transient damaging problem, and shows that venting to atmosphere of the catheter tip prior to the catheter removal prevents or reduces this transient damaging problem. The venting to atmosphere prevents a transient and partial vacuum formation for a transient cavitation. The invention disclosure shows the vent and method for preventing or reducing this transient cavitation damage.The prior art for self-catheterizing specifies six catheterizings per day. Thus, the prior self-catheterizing art specifies the catheter removals that precede the transient damaging problem. Although each catheter removal causes a small amount of damage, the repeated damage is cumulative and enlarges as subsequent catheter insertions disrupt the healing of previous damage. After many catheterizings, the transient cavitation damage at catheter removal leads to a serious bleeding problem.
