Discussion
Unlike Forero et al. that showed a large multidermatomic sensory block with the use of minor LA concentrations, our clinical case presented a multidermatomic anesthesiology plan with the use of LA at anesthetic concentrations. As suggested by Forero in his previous reports, it is probably due to the diffusion of the anesthetic solution both in the paravertebral space and in the peridural space.
Moreover US-ESPB has provided a long-lasting analgesia, probably due to the spread of anesthetic solution close to the intervertebral foramina, next to the origin of the dorsal and ventral branches of the thoracic spinal nerves, as suggested by cadaveric investigations.
Further researches, as also suggested by Fusco et al., should be necessary to confirm whether the US-ESPB could be an effective alternative to PVB (paravertebral block).
Paravertebral block (PVB) is currently the gold standard for management of chronic thoracic pain. Unfortunately, contraindications such as coagulopathies or anticoagulant therapies and the difficulty in performing the block, may determine the exclusion of many patients from this treatment.
Chin et al., in their work, have performed a US-ESPB at T7 level in a fresh cadaver and assessed the extent of injectate spread using computerised tomography. There was radiographic evidence of spread extending cranially to the upper thoracic levels and caudally as far as the L2-L3 transverse processes.
Our metameric extension tested with PinPrick and Ice test before surgery can be superimposable about what Chin showed in his work.
ESP-block compared to a LA does not alter the surgical plans and improves the outcome of the patient both in terms of analgesia and surgical times.
The clinical benefits that the US-ESPB has shown must obviously be evaluated on a larger patient court to further ensure the clinical validity demonstrated in this case report.
In fact, this anaesthetic technique could, in certain clinical cases, replace GA particularly in patients with respiratory and hemodynamic problems.