Pressure infusion bags, medical devices, use pressure to deliver fluids in clinical applications. However, residual fluid within these bags can affect drug dosing accuracy and treatment costs. Controlling residual fluid levels relies on optimizing device design, standardizing operating procedures, and improving supporting technologies. This requires comprehensive intervention across three aspects: structure, operation, and maintenance.
The material used in pressure infusion bags directly impacts the rate of residual fluid. Inadequate elasticity or flexibility can lead to insufficient deformation during pressurization, causing fluid to adhere to the bag walls. For example, infusion bags made of low-elasticity polymers may not fully rebound after pressure is released, leaving residual fluid trapped in folds. Improvements include selecting medical-grade silicone with high elasticity and low surface tension, or specialized coatings, to reduce fluid adhesion to the bag walls and minimize residual fluid. Furthermore, the bag's shape must conform to fluid dynamics principles, avoiding right angles or concave structures. A rounded bottom promotes fluid convergence toward the outlet.
Optimizing the infusion tubing system is crucial for minimizing residual fluid. When connecting a traditional infusion set to a medical pressure infusion bag, if the tubing has vertical sections or unnecessary bends, liquid may be retained due to gravity. Shortening the vertical tubing length and adopting a one-piece tubing design can reduce the risk of carryover in the fluid delivery path. Furthermore, adding a check valve or backflow preventer at the end of the tubing can prevent liquid from flowing back into the bag during pressure release, further reducing carryover. For infusion sets intended for multiple uses, regular replacement of filters and connectors can prevent leaks from aging components.
Precise control of the pressurization device significantly affects carryover. Uneven pressure regulation in manual pumps can cause sudden increases or decreases in bag pressure, leading to turbulent liquid flow and adhesion to the bag walls. Electric pressurization systems use intelligent sensors to monitor pressure in real time, maintaining a stable pressure output and reducing fluid fluctuations. Furthermore, some newer devices feature a pressure release compensation function that automatically reduces the pressure gradient at the end of an infusion to prevent carryover caused by sudden pressure changes. Operators should adjust pressure parameters based on the viscosity of the fluid and the infusion rate to avoid exacerbating carryover problems due to excessively high or low pressure.
Active recovery of residual fluid is an effective means of reducing fluid loss. At the end of an infusion, reverse pressure or negative pressure suction can be used to aspirate residual fluid from the bag into a reservoir. For example, a dual-chamber pressure infusion bag uses a secondary chamber to apply negative pressure after the primary chamber completes infusion, concentrating the residual fluid in a specific area for recovery through a dedicated channel. This method requires high-precision sensors and anti-contamination design to ensure that the recovered fluid does not back-contaminate the infusion system.
Standardized training in operational procedures is essential for controlling residual fluid. Failure of nursing staff to master proper venting techniques or pressurization timing can lead to increased residual fluid. For example, inadequate venting before connecting the infusion set can allow air to occupy space within the bag, reducing the effective infusion volume. Pressurization too early or too late can compromise fluid flow stability. Medical institutions should develop detailed operational guidelines and strengthen nursing staff's proficiency through simulation training.
Regular maintenance and quality testing are essential for ensuring stable equipment performance. Medical pressure infusion bag components, such as the seal and pressure gauge, require regular inspection to prevent leaks and inaccurate pressures due to aging or wear. For example, a aging seal can cause gas leakage during pressurization, resulting in insufficient bag pressure and residual liquid. Excessive pressure gauge inaccuracy can mislead operators into adjusting parameters. It is recommended to establish equipment maintenance records to record inspections after each use and promptly replace worn components.
From material selection to operating procedures, residual liquid control in medical pressure infusion bags must be implemented throughout the device's lifecycle. By optimizing structural design, improving pressurization technology, strengthening active recycling, standardizing operating procedures, and improving maintenance systems, residual liquid can be significantly reduced, improving the safety and cost-effectiveness of clinical medication use. In the future, with the further application of intelligent sensing technology and new materials, residual liquid control in medical pressure infusion bags will become even more precise and efficient.
