This chapter presents the indications, advantages, and procedures for vascular access techniques in children: intraosseous, central venous, US-guided peripheral venous, and umbilical venous access in the newborn.
Intraosseous access has the advantage of cannulating a noncollapsible structure that connects to the central circulation. The intraosseous approach is particularly useful for children as a result of their high percentage of red bone marrow and relatively thin bony cortex.
Intraosseous access is indicated when there is an emergent need for vascular access and other sites are difficult, high risk, or excessively time-consuming. Mechanical intraosseous insertion devices have insertion times of only seconds with consistently >90% success rates.1,2,3,4,5,6 Insertion devices include simple hand-twist needles, hand-held power drills, and spring-loaded devices.
There are few contraindications to intraosseous placement (Table 112-1), and the rate of serious complications from intraosseous insertion is ≤1%. The most common complication is extravasation at the insertion site. By comparison, central venous catheters have complication rates of at least 3.4%.7,8
TABLE 112-1Contraindications to Intraosseous Placement |Favorite Table|Download (.pdf) TABLE 112-1 Contraindications to Intraosseous Placement
Structural bone disorders (e.g., osteogenesis imperfecta)
MEDICATIONS AND FLUIDS ADMINISTERED BY THE INTRAOSSEOUS ROUTE
Any medication or fluid that can be given through an IV can be administered by the intraosseous route. Paralytics, anticonvulsants, analgesics, benzodiazepines, and vasopressors such as epinephrine have comparable intraosseous and IV infusion rates. Blood and blood products can be given by the intraosseous route.9 Medications for rapid-sequence intubation can be administered by the intraosseous route, although the time to effect may be delayed.10 In a study of sheep given IV or intraosseous succinylcholine, the IV route induced respiratory arrest in a mean of 30.8 seconds, whereas the intraosseous route took 57.5 seconds.11
The principal limitation of intraosseous access is a relatively low maximum flow rate. Resistance to flow within the bone marrow cavity limits the flow rate of intraosseous needles, and flow rates per kilogram tend to be higher in young patients who have a greater percentage of low-resistance red marrow compared to adults. The speed of administration of intraosseous infusions can be improved with pressure devices.
LABORATORY TESTING OF BONE MARROW ASPIRATE
The comparison of marrow aspirate with peripheral blood has been explored in small trials of hematology and oncology patients undergoing routine marrow sampling (Table 112-2). Two of these human studies have shown a close correlation of marrow aspirate to venous blood in regard to hemoglobin, sodium, chloride, bilirubin, pH, bicarbonate, urea, and creatinine concentrations.12,13 In another study, bone marrow taken for medical diagnosis ...