Medical instrument

A medical device comprising:

• a fluid routing structure;
• a shaft extending within at least a portion of the fluid routing structure;
• a flow restriction tube surrounding the shaft within the fluid routing structure;
• and
• a flow restriction tube stop positioned proximally of the flow restriction tube;
• wherein pressure from a fluid introduced against the flow restriction tube causes the flow restriction tube to translate proximally with reference to the shaft until the flow restriction tube contacts the flow restriction tube stop;
• and
• wherein contact between the flow restriction tube and the flow restriction tube stop restricts the fluid from traveling proximally past the flow restriction tube stop.

A medical device comprising:

• a shaft comprising a distal end portion;
• a beam comprising a proximal end portion and a distal end portion, the proximal end portion of the beam being coupled to the distal end portion of the shaft;
• a body coupled to the distal end portion of the beam;
• a shroud comprising a proximal end portion, a distal end portion, and an inner wall between the proximal end portion and the distal end portion of the shroud;
• and
• a bushing comprising a proximal end portion and a distal end portion, the proximal end portion of the bushing is coupled to the distal end portion of the shaft and
• the distal end portion of the bushing is located between the distal end portion of the shaft and the proximal end portion of the shroud.
• wherein the distal end portion of the shroud is coupled to the body;
• wherein the proximal end portion of the shroud is located between the distal end portion of the shaft and the body;
• and
• wherein the inner wall of the shroud defines an interior volume configured to receive a fluid that flows through the interior volume of the shroud and is directed proximally toward the distal end portion of the shaft.