The objective of this study was to examine the incidence and success rate of intraosseous (IO) needle utilization in emergency situations within both pediatric and adult populations. The implementation of IO access was carried out in 0.27% of patients admitted to this level 1 trauma center, demonstrating an high overall clinical success rate of 97%.
The incidence of IO needle placement in this cohort (2.7 per 1000 ED visits for adults and 0.87 per 1000 ED visits for pediatrics) was higher as compared to other countries United States (0.05 per 1000) and Japan (0.34 per 1000) [12] [13]. However, in contrast to these studies, our study only contains patients admitted to a level 1 trauma center which makes it more likely that this cohort contains more severely injured or ill patients. For these severely injured patients, rapid and early vascular access is important and should be performed in a prehospital setting. No discernible disparity is observed between prehospital and in-hospital intraosseous (IO) needle placement, as noted by Wampler et al., who reported a first attempt success rate of 91%, increasing to 94% after a second attempt [14]. Our findings corroborate that the environment does not present an obstacle to IO placement. Consequently, IO access should be conducted in all environments, including prehospital settings.
The overall success rate of 97% in this study is comparable to other scientific reports. The randomized controlled trial conducted by Reades et al. reported a success rate of 91% for IO needle placement [15]. However, the clinical success rate drops in pediatric patients. We demonstrated that children aged 6 months or lower had lower success rates (71%) as compared to the overall success rate. There are several explanations for these results, that are in line with the study performed by Myers et al. [16] First, the target area of the pediatric tibial bone is small, with smaller bone shafts and largely cartilaginous epiphyses. Additionally, adults have the advantage of having a flat cortical surface along the medial aspect of the tibia, with only a thin cover of soft tissue. In an infant’s tibia, the tibial target area has a more rounded contour [17]. Besides the greater target area and larger bone size in adults, there is also a thicker cortex in the bone marrow. Because of the thinner cortex in infants, any slight movement of the IO needle after entering the bone marrow would likely result in greater chance of dislocating and failing [9]. Second, there may also be an association between needle length and failure [9]. Harcke et al. revealed that a 25-mm needle was not successful in six out of seven placements in infants of 2 years of age or younger. Among patients that had a 15-mm needle, 18 of 29 needles were within the medullary cavity of the bone marrow Harcke et al. report that the 15-mm needle length has a poor success rate in small infants and advice caution in using this IO needle for young infants [17]. The advised length for pediatric patients from 3–39 kg weight is 15mm, 25 mm for adult patients > 39 kg weight and 45 mm in length for obese patients [18]. In contrast to other studies, body mass index was not correlated to success rate. For example, Pifko et al. described a success rate of 97% in patients > 8 kg and 47% for patients < 8 kg. They equated 8 kg to an average age of 6 months; although this study grouped patients by age, comparison between the studies is nonetheless valid [9]. For neonatal patients IO access seems even more challenging [19]. To improve the success rate of IO needle use in children under the age of 6 months and patients with lower body weight, more routine IO simulation training may be beneficial [9].
This study found a 7.7% complication risk for IO needle use, a lower percentage as compared to IV access (23–44%) [20] [21]. However, adverse events after IO access are often severe such as extravasation, compartment syndrome, pain, osteomyelitis, growth plate injuries and fracture. Beyond a few case studies, no numbers are known for the incidence of compartment syndrome after using an IO needle. A meta-analysis review of 4.270 cases of IO needles found 27 (0.63%) cases of osteomyelitis [22]. In the present study, there was one case in which the needle may have penetrated the growth plate. It has been shown that penetration of the growth plate does not result infusion in a subsequent leg length discrepancy [23]. Although the frequency of adverse events is low, misplacement can lead to serious complications. To investigate influencing factors on the success rate especially in infants aged < 6 months, further research should be conducted in a prospective setting.
Despite IO needles are a safe and effective tool for rapid access, intravenous access remains and will be the golden standard for most cases. Understandable, since it is less invasive and burdensome for the patient. However, a randomized controlled trial (RCT) comparing IO and IV access during cardiac arrest, revealed a 48% difference in first attempt success rate in favor of IO access [15]. Also during trauma resuscitation, first attempt IO needle placement were higher as compared to first attempt intravenous access [3]. In this study, no separate analysis was performed for these patient groups.
Limitations
This is a retrospective database study based on documented IO needle use. The study design may have led to underestimation of the incidence and success rate of IO needle in the ED due to the insufficient data reportion. Several devices exist for IO insertion, including First Access for Shock and Trauma (FAST1), the EZ-IO, and the Bone Injection Gun (BIG). In addition, the definition of success was based on retrospective interpretation of file notes. In patients with no other infusion system mentioned beyond the IO needle, the documentation of successful injection of drugs is interpreted as a clinically successful IO needle use. The retrospective design of this study has limitations. It was not possible to extract variables such as needle length, the experience of an individual health care professional, or the time needed to insert the needle from the files, but these variables may have affected patients’ outcomes. Additionally, other variables were not always documented, such as weight, blood pressure, and heart rate. It is imaginable that due to this low reportion rate, the multivariate analysis was not significant. The limited documentation could be explained by the emergent setting given that there is little time and a hectic atmosphere in the ED.