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.