Systems, apparatus, and methods for reducing fluid pressure in a fluid line

An apparatus, comprising:

• an outer tube having a first end and a second end and defining a lumen;
• an inner tube having a first end and a second end and defining an expandable reservoir having a first volume, the inner tube disposed within the lumen of the outer tube, the first end of the inner tube coupled to the first end of the outer tube via a first end connector, the second end of the inner tube coupled to the second end of the outer tube via a second end connector, the first end connector configured to be coupled to a first tube portion such that a lumen of the first tube portion is in fluidic communication with the reservoir of the inner tube, the second end connector configured to be coupled to a second tube portion such that a lumen of the second tube portion is in fluidic communication with the reservoir of the inner tube, a sidewall portion of the inner tube being sufficiently compliant such that the inner tube is configured to expand laterally relative to a central axis of the inner tube when a pressure level of a fluid within the reservoir increases such that the reservoir has a second volume greater than the first volume, and the sidewall portion being resiliently biased toward the first volume such that the inner tube is configured to apply a force to the fluid within the reservoir to expel the fluid from the reservoir as the pressure level of the fluid within the reservoir decreases.

An apparatus, comprising:

• a housing defining an interior, the housing having a first end and a second end, the first end of the housing configured to be fluidically coupled to a tube portion;
• a spring member disposed within the interior of the housing, the spring member having a first end and a second end, the second end of the spring member coupled to the second end of the housing, the spring member resiliently biased toward an expanded configuration;
• and
• a seal member disposed in the interior of the housing and coupled to the first end of the spring member, the seal member and the housing collectively defining a reservoir having a first volume, the seal member configured to translate within the interior of the housing such that, when the first end of the housing is fluidically coupled to the tube portion such that the tube portion is in fluid communication with the reservoir and when a fluid pressure of a fluid in the tube portion and the reservoir increases, the fluid applies a force to the seal member such that the seal member translates toward the second end of the housing and the spring member transitions from the expanded position to a compressed position such that the volume of the reservoir increases from the first volume to a second volume greater than the first volume as fluid is received into the reservoir.

A method, comprising:

• expelling fluid from a fluid pressure source to a tube portion at a source pressure such that fluid is delivered to a patient via the tube portion and fluid is delivered into a reservoir of a fluid pressure regulating device, the fluid pressure regulating device coupled to the tube portion such that the reservoir of the fluid pressure regulating device is in fluidic communication with a lumen of the tube portion, the fluid delivered into the reservoir causing a volume of the reservoir to increase;
• discontinuing the expelling of fluid from the fluid pressure source to the tube portion;
• and
• allowing the fluid pressure regulating device to deliver fluid from the reservoir of the fluid pressure regulating device to the patient via the tube portion.