Transdermal spinal catheter placement in piglets: Description and validation of the technique.

BACKGROUND: The swine species represents a perfect model for translational medicine due to its physiological and anatomical resemblance to humans. The development of techniques for spinal catheter insertion in swine is significantly useful but, at the moment, the only technique described requires laminectomy as a surgical approach. NEW METHOD: The proposed techniques represent a transdermal approach for catheter placement in piglets. The study was divided into Phase I (anatomical study on 8 cadavers) and Phase II (in vivo application of the technique in 20 anaesthetised 30-day old piglets). A spinal needle was introduced between the L2 and L3 spinous processes with a ventro-cranial orientation until cerebro-spinal fluid leakage. It was then replaced with a Tuohy needle, used to introduce the catheter into the intrathecal space. Before inserting the catheter, the approximate length from the insertion point to the external projection of the Cisterna Magna was measured using the gradation markings on the device. RESULTS: The technique described allowed spinal catheter placement in all piglets. In Phase I, the correct placement was confirmed using fluoroscopy while, in Phase II, cerebrospinal fluid leakage from the needle was relied on. No clinical alterations were detected either during the procedure or during the following days. COMPARISON WITH EXISTING METHOD: This technique is easy and requires less skilled operators when compared to the other existing method which involves a surgical approach. Moreover, being less invasive, it potentially leads to fewer complications. CONCLUSIONS: In conclusion, the technique can be performed safely in piglets, and provides an easier and less invasive approach for spinal catheter insertion