Intraosseous (IO) cannulation is an effective and reliable means of rapidly accessing the central circulation for the administration of fluids, medications, and blood products. The non-collapsible intramedullary venous sinuses offer great stability during states of profound vasoconstriction and circulatory failure, such as shock and cardiac arrest, when peripheral access is emergently needed but untenable.^1,2 Highly vascular marrow spaces are capable of absorbing large volumes of fluids, medications, and blood products with rapid distribution to the rest of the body.³ The procedure can be safely performed with minimal training by pre-hospital providers as well as by staff skilled in pediatric hospital, emergency, or critical care medicine.^4,5 Power-assisted devices for IO placement have made this procedure even more accessible to providers of all skill levels.^6-8

IO access is indicated for pediatric patients requiring resuscitative efforts in whom placement of a peripheral intravenous catheter is unsuccessful or cannot rapidly be established.^1,2 For patients in cardiac arrest, IO placement should be performed before all other means of securing access and should be considered early as an alternative to central venous access in the resuscitative efforts of patients with sepsis in whom peripheral access cannot be readily obtained.^1,9 The procedure can be attempted in patients of any age in whom peripheral access is unsuccessful.¹⁰

Manual IO cannulation is generally successful in 30 to 60 seconds.¹ Access with powered devices can be achieved in as little as 5 to 10 seconds with success rates of >90%.^11,12 IO catheters are intended to be used during immediate resuscitative efforts only.¹ Once a patient has been stabilized, peripheral IV or central venous access should be secured for long-term use.

IO lines can deliver any medication, fluid, or blood product prepared for intravenous administration.^3,13 A strong evidence base supports IO use for neuromuscular blockade as well as for resuscitative medications such as catecholamines (bolus preparations and continuous infusions), lidocaine, calcium, and sodium bicarbonate.^14-18 In general, the onset of action and drug levels in the central circulation following IO delivery are comparable to those achieved with intravenous administration.^1,16 Boluses of crystalloids, colloids, blood products, and viscous medications must be delivered under pressure, either manually with a large-caliber syringe or with the assistance of a pressure bag, to overcome the resistance of the emissary veins running through the bony cortex, which are responsible for transporting materials from the intramedullary space to the central circulation.¹⁰

Blood samples obtained from the marrow space can be sent for culture and type and cross-match, and can be used to analyze pH, hemoglobin, bicarbonate, and electrolytes with accuracy comparable to venous blood samples.^19,20 Importantly, blood obtained from the medullary cavity does not reflect an accurate peripheral complete blood count and differential.

Few contraindications to the use of IO catheters exist. Absolute contraindications include a recent fracture in the bone to be used for the procedure, recent unsuccessful IO attempt in the same bone, or underlying bone disease such as osteopenia or osteogenesis imperfecta given the high risk of fracture in these patient populations.^1,3 Relative contraindications include overlying cellulitis or burn at the site of puncture.

Needles used for IO cannulation should be sturdy enough to penetrate bone and long enough to reach the marrow cavity.³ Several catheters can be used to establish IO access: the Jamshidi bone aspiration-infusion needle, the Cook IO infusion needle, or a wide-gauge spinal needle with an internal stylet. There are also several semiautomatic devices available for IO insertion including the battery powered EZ-IO drill (Vidacare, San Antonio, TX) and the spring-loaded Bone Infusion Gun (BIG) (Weismen, Yokemen, Israel) All function effectively, but the evidence base suggests that the EZ-IO may be placed most rapidly.^7,11 The Jamshidi infusion needle may be placed with greater ease than the Cook infusion needle and the BIG.^21,22

Table 192-1 lists the other equipment needed for IO placement.