The IV set must be adjusted according to the patient and planned surgical procedure. Microdrop infusion sets (60 drops/mL) allow anesthesiologists to deliver small infusions to children more accurately than standard 15 drops/mL infusion sets. For older children (about 10 years and older), a standard adult infusion set is sufficient. The addition of extension tubing to all pediatric infusion sets allows placement of IV catheters in any available limb and allows small children to be moved down the operating table for better surgery. Inserting multiple stopcocks in an infusion line can deliver precise amounts of blood or colloids and minimize the need to use needles to access the infusion. The blood set is attached to the plunger closest to the patient and the syringe is placed in the stopcock furthest away from the patient. The stopcock is opened to allow blood to flow into the syringe, and then adjusted to inject the exact volume of blood from the syringe into the patient. All infusion sets should be "debubble" prior to use to prevent air from entering the circulatory system, this is especially important for premature infants who may have a patent foramen ovale or patent ductus arteriosus, or known intracardiac Children with defective or persistent patent foramen ovale. To reduce the incidence of accidental needle stick injuries, all manufacturers now offer injection ports throughout the length of the tubing, which can be accessed via standard syringes or specialized blunt adapters. When accessing these ports, care must be taken to avoid air that often accumulates in these ports.
In the face of severe hypovolemia due to rapid blood loss or other causes of severe intravascular volume depletion, a rapid infusion of blood or crystalloids can prevent impending disaster. The speed of the infusion is directly related to the driving pressure of the infusion and the resistance of the infusion. Unless a small-bore infusion tube is used to reduce infusion dead space, the resistance of the infusion circuit is primarily related to the length and diameter of the venous catheter. Short catheters with larger IDs have less resistance than longer catheters with smaller diameters, regardless of peripheral or central location. The driving pressure for an intravenous solution depends on the height of the fluid bag, gravity, or the mechanical force used to push the solution. As mentioned above, an easy way to increase infusion rates in newborns and young children is to use the push-pull technique. By drawing blood or fluid into the syringe, the fluid can be "pushed" into the patient at a significant rate, especially in children weighing less than 40 kilograms. Disadvantages of this technique include the need to perform tasks manually and the risk of infection, which can increase with reuse of the same syringe. Advantages include the ability to accurately deliver fluids at a brisk pace while manually sensing changes in system resistance that could indicate venous catheter infiltration.
Pressurized or mechanically pumped intravenous solutions or blood can also significantly increase the rate of infusion. The driving pressure of the solution can be significantly increased by placing an inflatable sleeve over the infusion bag. By using a hand pump (C-Fusor, Smith Medical North America, Dublin; Ohio; Infu-Surg, Cardinal Health; Dublin, Ohio), the cannula can be gradually inflated to 300 mm Hg for infusion of blood or intravenous solutions Inside the patient. Disadvantages of this system include the need to manually inflate the pressurized device, the inability to accurately deliver small volumes of fluid, the fluid leaking out of the vein, and the risk of air embolism due to accidental insufflation of air (Linden et al., 1997). Special care needs to be taken to remove trapped air from the blood or infusion bag prior to spiking the blood or infusion bag. The venous line should be checked for free flow and venous patency before using the bolus system. By using a pressure system to fill a push-pull syringe that is already set up, without the need to manually fill the syringe, the accuracy of the infusion volume can be improved. Any trapped air can be removed using a syringe system. Automatic pressure infusion sets (Level 1 H-1200, Smith Medical North America, Dublin, Ohio; Ranger A1400, Arizant Healthcare; Prairie, Minnesota) eliminate the need for manual inflation by using high-pressure air or electricity to generate actuation pressure. These The device has a fluid heater and an air detector as an integral part or accessory and can quickly deliver large quantities of warm liquids through a special disposable infusion set. Roller pump technology has also been used to rapidly infuse blood or intravenous solutions. Combined with electromagnetic heaters, air detectors and electronic flow control, this technology can be used to accurately deliver large volumes of heated liquids. Because of the greater risk of air with high pressure infusion sets, any automated equipment used must stop delivering fluids if air is detected in the line. Hemolysis and hyperkalemia can also be a problem if blood is delivered through an IV catheter using a rapid infusion set