The Sonographic Appearance of Spinal Fluid at Clinically Selected Interspaces in Sitting Versus Lateral Positions

Abstract

Ultrasound can verify the presence of fluid at interspaces determined by the landmark palpation technique and identify additional suitable spaces at higher levels. There were statistically greater fluid measurements in sitting versus lateral positions. These novel fluid measurements were shown to be reliable.

The Variability of Preferred Infant Lumbar Puncture Insertion Site Between Novice and Experienced Physicians

“…Given that we found slightly larger subarachnoid spaces at more superior insertion sites, one could theorize that these sites are more likely to be associated with LP success. Previous studies have examined the effect of positioning or fluid boluses on the size of the subarachnoid space, but no studies to date have studied the relationship between subarachnoid space size and LP success.…”

“…US has been previously used to determine optimal LP positioning, to increase the confidence of the proceduralist, and to mark the insertion site . In one US study, 41% of selected insertion sites had two additional suitable spaces superior to the selected site . As trainees tended to mark a preferred insertion site more caudal than attending physicians, our study supports the anecdotal suggestion to attempt “one space higher” after an initial unsuccessful trainee attempt.…”

“…Point‐of‐care ultrasonography (POCUS) allows providers to visualize the anatomic landmarks of LP, which may help improve success rates . In children, POCUS has been utilized to increase provider confidence in choosing the LP insertion site and to select alternative suitable interspaces . Most importantly, it has been utilized to mark the LP insertion site, leading to increased success …”

Point-of-Care Ultrasound for the Evaluation and Management of Febrile Infants

“…Point-of-care ultrasound has also been shown to identify safe intervertebral spaces above those identified by traditional landmark palpation technique in infants. 22 When considering repeated attempts and avoiding traumatic samples, US-assisted LP has particular utility. Frequently, blind advancement of the spinal needle beyond the subarachnoid space leads to a bloody CSF sample.…”

“…These 3 studies suggest that there is definitive evidence for experienced operators to use POCUS to improve success rates of LP in infants, among other advantages. Point-of-care ultrasound has also been shown to identify safe intervertebral spaces above those identified by traditional landmark palpation technique in infants 22 …”