It’s a tautology!
In a solid “not news, but newsworthy” systematic review and meta-analysis published in The Lancet, these authors pooled data from 110 trials comparing conventional (“cutting”) spinal needles with “atraumatic” ones. The atraumatic ones, after all, are thought to result in less tissue damage and corresponding complications. The perceived downside to the atraumatic needles, however, is related to potentially decreased procedural success.
In short, none of the results favor the conventional needles. The sample sizes for each measure ranged from 24,000 patients to 1,000, with most right in the middle of the range. These authors evaluated incidence of such complications as post-procedural headaches, need for analgesia, need for epidural blood patch, nerve root irritation, or hearing disturbances. With regard to procedural success, these authors evaluated the traumatic taps, first attempt success, and overall procedural failure rate.
The magnitude of reduction in various complications was wide, but consistent. In an absolute sense, any post-procedural headache associated with use of atraumatic needles was from 12% to 7%, and the need for epidural blood patch decreased from 2% to 1%. With regard to any reduction in procedural success, no signal of difference was observed.
The authors accurately report there is low awareness of the advantages of the atraumatic needles among clinicians. These data, even if not novel, at least are published on an adequate platform to improve awareness of the superior alternative.
“Atraumatic versus conventional lumbar puncture needles: a systematic review and meta-analysis”
https://www.ncbi.nlm.nih.gov/pubmed/29223694
A tautology but a wrong one.
Atraumatic is traumatic, hence it works, according to this paper.
I love paradoxes.
https://www.ncbi.nlm.nih.gov/pubmed/10925937
An in vitro study of dural lesions produced by 25-gauge Quincke and Whitacre needles evaluated by scanning electron microscopy
CONCLUSIONS:
The needles produced lesions in the dura with different morphology and characteristics. Lesions with the Quincke needles resulted in a clean-cut opening in the dural membrane while the Whitacre needle produced a more traumatic opening with tearing and severe disruption of the collagen fibers. Thus, we hypothesized that the lower incidence of PDPH seen with the Whitacre needles may be explained, in part, by the inflammatory reaction produced by the tearing of the collagen fibers after dural penetration. This inflammatory reaction may result in a significant edema which may act as a plug limiting the leakage of cerebrospinal fluid.
Brilliant, my good sir!