**7.1. Procedure and features**

For performing bowel ultrasound a linear probe of 8–15 MHz probe (higher frequency for higher resolution and lower depth targeting superficial structures). Features that are key include: (a) bowel wall thickening >2.6 mm, (b) increase in bowel wall echogenicity, (c) portal venous air, (d) pneumatosis Intestinalis and free air and (e) intra-abdominal fluid.

shown to be accurate only 30% of the time [47]. Traumatic or unsuccessful LPs in this group have been documented in the pediatric literature in 30–50% of patients [48, 49]. This translates to increased difficulty in obtaining CSF and higher rate of complications such as local/ subdural/epidural hematoma, bloody tap and incomplete sepsis evaluation to name a few. Fluoroscopy guided LP is an alternative but challenges include limited availability, radiation

Current Neonatal Applications of Point-of-Care Ultrasound

http://dx.doi.org/10.5772/intechopen.79441

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Use of POCUS for identification of key landmarks is a safe and easy alternative to the blind method [50–52]. In adults, using ultrasound for LP has been associated with a reduction in the number of attempts and interspaces accessed [51–55]. In neonates, the incompletely ossified spinous processes, minimal fat aids in interrogation of the space by ultrasound compared to older kids and adults. The good resolution of image, lack of ionizing radiation and potential for real time guidance makes ultrasound a valuable tool for performing LP in

LP can be performed in the neonate without general anesthesia or sedation, using oral sucrose and local anesthesia. Patient can be in lateral decubitus position or sitting up. Using ultrasound to measure the interspinous space at L3-L4 and L4-L5 in varying positions, the lumbar spine is found to be maximally positioned in both neonates and children in the seated position with flexed hips versus the lateral decubitus position [57, 58]. The probe used is the 7–15 MHz hockey stick or equivalent linear array transducer. There is still very limited knowledge on ultrasound guided LP in neonates. There are two techniques described in literature, the trans-

The first skill is to define the landmarks for the LP procedure. Using a surgical marker or pen one can delineate the location of midline and the position of the conus, the point where the spinal cord ends. There are no studies validating the guidance of the needle into the interspace and so this will require more studies before guidance by US is a routine procedure.

Existing and emerging POCUS applications are numerous and promising but more validation for clinical value is required in addition to larger scale training of individuals to learn and become competent in these techniques. Emphasis should be on training all incoming and

and Azif Safarulla2

1 University of California San Diego and Rady Children's Hospital of San Diego, San Diego,

verse approach and longitudinal approach based on how the probe is held.

exposure, need to transport critical patients for the procedure.

neonates [48, 56].

**10. Summary**

**Author details**

Jae H. Kim1

California, USA

existing fellows to learn POCUS.

\*, Nikolai Shalygin1

\*Address all correspondence to: neojae@ucsd.edu

2 Augusta University, Augusta, Georgia, USA

**Figure 7.** Sonographic appearance of NEC progression (figure from Epelman et al. 38 need permission).

Some limitations of ultrasound include that it is operator or skill dependent and this is a real time diagnosis which might create an obstacle for radiologists to evaluate the ultrasounds retrospectively and in turn underlines the need for neonatologists to be more familiar with this tool. Currently most of the available literature are single center trials, retrospective observational cohorts. We still need more prospective studies doing head to head trials with abdominal radiograph to understand the true value and usefulness of abdominal US. More studies are required to fully validate these assessments in clinical care. Training of radiologist and their sonographers as well as other providers such as neonatologists and surgeons is required before broad adoption of bowel POCUS occurs.
