Detection of Epithelial Cell Transfer in Spinal Areas by Light Microscopy and Determining Any Tissue Coring via Cell Culture During Combined Spinal-Epidural Interventions

Cerebrospinal fluid cytology in patients undergoing combined spinal epidural versus spinal anaesthesia without an introducer

The problem of tissue coring exists despite the availability of smaller gauge spinal needles with special tip designs. The aim of the study was to test the hypotheses that a) subarachnoid block given as a part of a combined spinal epidural intervention by needle-through-needle technique introduces a lesser number of epithelial cells into the subarachnoid space compared to isolated subarachnoid block, and b) after lumbar puncture, the initial few drops of cerebrospinal fluid from the spinal needle will have a higher number of epithelial cells than the subsequent sample. One hundred and seven patients of American Society of Anesthesiologists physical status I to III undergoing infra-umbilical surgery were enrolled. Seven patients were excluded from the study and the rest divided into two groups to receive either combined spinal epidural anaesthesia (group A) or isolated subarachnoid anaesthesia, unaided by an introducer (group B). The two groups were compared for the presence of epithelial cells in cerebrospinal fluid. The initial four to six drops of cerebrospinal fluid (sample 1) were collected, the next four to six drops discarded and the following four to six drops (sample 2) collected. The incidence of coring was 96% in group A and 88% in group B (P = 0.142). The median (interquartile range) number of cells in group A, for samples 1 and 2 was 6 (3 to 12.5) and 6 (3 to 10); and in group B, 3.5 (1 to 10) and 4 (1 to 8) respectively. Significant tissue coring was observed with both techniques. Discarding eight to 12 drops of cerebrospinal fluid did not help in reducing the epithelial cell load.

Comparing tissue coring potentials of hollow needles without stylet and caudal needles with stylet: an experimental study

BACKGROUND AND OBJECTIVES

Although the association of tissue coring and development of epidermoid tumour has been proposed, the extent and frequency of such coring is still controversial and the viability of carried cells has not been substantiated. In the present study, we used an experimental model without needle removal to investigate the incidence of tissue coring using two different needle types.

METHODS

We inserted 22-G caudal (n = 34) or 22-G hollow (n = 25) needles to the tumour-free areas of fresh modified mastectomy specimens. The specimen was stretched and needles were inserted perpendicular to the skin and forced to penetrate the full thickness of the specimen. Without removing the needle, the needle cavity was then washed with 2 mL of RPMI 1640 with L-Glutamine and the washings were collected in a 15-mL falcon tube. The tubes were sealed and labelled and processed to obtain cytologic preparations. The slides were evaluated under a light microscope.

RESULTS

A high rate of epithelial cell transportation was noted. All the carried cells were stratum corneum cells with no nucleus. No nucleated cells were seen. The incidence of carried cells was 64.7% and 72.0% in the caudal and hollow needle groups, respectively (P > 0.05).

CONCLUSION

Only cells from the outermost layer, stratum corneum, which is made of dead flat skin cells, were transported with needle puncture. The risk of epidermoid tumour development after regional anaesthesia must therefore be low. The incidence of transporting non-nucleated stratum corneum cells was similar between hollow and caudal needles.