Self sealing proximal microcatheter and access aid

A blood flow occlusion flushing device, comprising:

• a first catheter having a proximal end, a distal end, and a lumen extending through the first catheter from the proximal end to the distal end;
• a second catheter disposed within the lumen of the first catheter, the second catheter having a proximal end, a distal end, and a lumen extending through the second catheter from the proximal end to the distal end, the second catheter being axially movable with respect to the first catheter, the second catheter having a port in the sidewall proximate the distal end of the second catheter;
• a guidewire disposed within the lumen of the second catheter, the guidewire being axially movable with respect to the second catheter, the guidewire having a proximal end and a distal end, the guidewire having a first diameter that is less than an inner diameter of the second catheter, the guidewire having a radially outwardly projecting bump proximate the distal end of the guidewire, the radially outwardly projecting bump having an outer diameter that is approximately equal to an inner diameter of the second catheter at the distal end of the second catheter such that when the radially outwardly projecting bump is aligned with the distal end of the second catheter, the radially outwardly projecting bump being in sealing contact with the inner diameter of the second catheter at the distal end of the second catheter such that a fluid deliverable through the lumen of the second catheter via the proximal end and exiting the port in the sidewall of the second catheter.

A retrograde blood flow occlusion flushing device, comprising:

• a first catheter having a proximal end, a distal end, and a lumen extending through the first catheter from the proximal end to the distal end, the first catheter having an inflatable balloon connected to an outer circumferential surface of the first catheter at the distal end of the first catheter, the balloon being movable between a collapsed state and an inflated state, the balloon being fixedly connected to the outer circumferential surface of the first catheter at a proximal endof the balloon and at a distal end 34 of the balloon, the first catheter 20 having a port 36 in the sidewall between the proximal end of the balloon and the distal end of the balloon, the balloon having at least one port proximate the proximal end of the balloon;
• wherein the balloon is movable between the collapsed state and the inflated state by a fluid deliverable through the lumen of the first catheter via the proximal end and exiting the port in the sidewall of the first catheter to selectively move the balloon between the collapsed state and the inflated state;
• in the inflated state, the fluid being deliverable through the lumen of the first catheter, through the port in the sidewall of the first catheter to inflate the balloon and at least some of the fluid exiting the inflated balloon in the proximal direction through the at least one port in the balloon.