Intraosseous (IO) vascular access use in children began in the 1940s, but the practice was abandoned when intravenous catheters were invented. A resurgence of interest in IO access began decades later, and the procedure was first added to the Pediatric Advanced Life Support guidelines in 1986. Intraosseous access has now become the preferred access method over central line placement and for peripheral IV access that takes longer than 30 seconds.
Initially, manual intraosseous needles were used for neonatal resuscitations because they were the only tools available. Once we learned the skill, manual IO needles served their purpose well. Cup the needle top in your palm and insert the needle with a rotational pressure perpendicular into the bone until you feel a trapdoor effect as the needle passes through the cortex into the medullary space. Later, when the EZ-IO drill was invented for IO needle insertions, we immediately fell in love and our affections for the manual IO needles waned. Now, however, evidence suggests that our first love, the manual needles, deserves to be reconsidered for attaining intravenous access in neonates.
Umbilical venous access is often recommended for emergency venous access in newborn resuscitations. That procedure, however, is rarely performed for newborns, and maintaining the equipment and skills are challenging. In fact, it is reportedly done in only 0.12 percent of all births. (Arch Pediatr Adolesc Med. 1995;149:20.)
Consequently, emergency physicians are significantly less experienced with this technique. Umbilical venous catheterization is an important skill, but studies show that it is significantly faster to establish intraosseous access than an umbilical venous catheter. (Pediatrics. 2011;128:e954; Pediatr Crit Care Med. 2018;19:468.) My ED doesn't place many intraosseous needles because our nurses are skilled at placing intravenous catheters in even the smallest neonates. Nevertheless, the smallest neonates presenting in cardiac arrest are the ones who may require IO needle placement for intravenous access.
Evidence suggests that manual and EZ-IO access are associated with a significant number of failures in neonates because of small bone size and the difficulty in judging the depth and when the needle passes into the medullary space. The trapdoor sensation as the needle drops through the cortex is much easier to detect with manual IO needles than drill-inserted ones. The shortest EZ-IO needle used for neonates is vulnerable to adipose tissue back pressure in chubby neonates even when you maintain the 5-mm-of-needle-above-the-skin rule. I have seen perfectly placed needles dislodged moments later by the mechanics of adipose pushing back on the needle hub.
The question is whether the EZ-IO drill is the most appropriate tool for this procedure. A relatively large study survey suggested the drill can be highly successful. (Front Pediatr. 2022;10:952632; http://bit.ly/3XH6ea8.) A total of 206 IO access attempts were made in 161 neonates (145 term and 16 preterm infants), and IO access was successfully established in 146 (91%) and on the first attempt in 109 (75%). A semiautomatic battery-driven device (EZ-IO) was used in 162 attempts (88%). This seems to be a strong affirmation for using the EZ-IO, but this was a mandated two-year anonymous report to a nationwide surveillance unit. I am not confident that there wasn't some potential for reporting bias.
There is other hard evidence that our success rates with intraosseous needle placement in infants is nowhere near that pristine. Several smaller, post-mortem studies suggest our failure rate for neonates is much higher. A review based on postmortem CT scans found that tibial IO needle insertion had a 53 percent failure rate (31 cases with 42 devices) in infants 6 months and younger. (Prehosp Emerg Care. 2020;24:665.) A study using pediatric cadavers reported that 16 of the 34 ION devices (47%) were malpositioned. (Resuscitation. 2019;145:1.)
Another study observed poor success rates with manual and EZ-IO devices in children under 8 kg compared with those over 8 kg. Manual IO had success rate of 55 percent (17/31) vs. 47 percent (8/17) for the EZ-IO (p=0.61) in patients 8 kg or less. (J Paediatr Child Health. 2018;54:546; http://bit.ly/3VxIHqg.) Manual and EZ-IO driver placement success rates in neonates were nothing to brag about. On the other hand, manual IO did have a shorter time to placement: 4.5 min versus 12.8 for EZ-IO (p=0.02). (J Paediatr Child Health. 2018;54:546; http://bit.ly/3VxIHqg.) There is another smaller, albeit low-quality study that suggests that manual insertion techniques with butterfly needles may have higher success rates. One study reported manual success rates of 61 percent for butterfly needles, 43 percent (95% CI:23.4%-65.0%) for hand-twisted EZ-IO screwing, and 39.7 percent for the semi-automatic drill (Arrow EZ-IO). (Resuscitation. 2018 Jun;127:79.)
Be aware of the challenges of using the drill. This video documents my own failure with the EZ-IO driver during a neonatal resuscitation. Manual insertion of IO needles may be the faster tool for vascular access, but it is not clear whether this is clinically significant. Nevertheless, I believe we should add manual IO needles back to our intravenous resources for newborns and neonates.
We learned recently that one brand of manual IO needles commonly used for neonates had been recalled, but we learned that the needles sold with the EZ-IO drill are also approved for manual application. Problem solved!