Print version ISSN 0034-7094
Rev. Bras. Anestesiol. vol.56 no.2 Campinas Mar/Apr. 2006
LETTERS TO THE EDITOR
Radiological evaluation of the spread of different local anesthetic volumes during posterior brachial plexus block
I thank you the opportunity to add some comments to the work of Cruvinel et al. 1. Unforeseen anatomical accidents may interfere in the distribution of the anesthetic solution during the brachial plexus block by any approach. The paravertebral anesthesia is not recent. In 1912, Max Kappis, German surgeon, excited due to his colleague Läwen accomplishment of having carried out a nephrectomy under paravertebral anesthetic blockade, expanded the technique with Novocain, 5 mL in each approach to the vertebral transverse process, for surgeries in the superior member and cervical area (cervical paravertebral), toracotomies and breast surgeries (thoracic paravertebral), laparotomies associated to the direct blockade of the celiac ganglion and inguinal herniorraphies (abdominal paravertebral) 2. Almost 80 years later, the Italians Pippa et al. 3 have reintroduced the practice of the cervical paravertebral block of Kappis to the arsenal of the regional anesthesia on the brachial plexus. In fact, the most appropriate denomination should be brachial interescalenic block by posterior pathway 4. Not only the administration technique, as well as different anesthetic volumes have been presenting several results. This can be inferred from the work of Cruvinel et al. 1, in which administering by means of a catheter a volume of 10 mL of anesthetic and contrast (Figure 5), the latter mimetized a more comprehensive plexular distribution than with a volume of 30 mL (Figure 2) per a single injection, proving that the injection through the catheter provides a better quality dispersion with smaller volume. While with single volumes varying between 20 mL and 40 mL, the dispersion difference presented minimal variations. Another important data of this kind of blockade is the inconstancy of reaching the ulnar nerve [(C7),C8,T1]. Moreover, this fact is apanage especially of the supraclavicular approaches by any pathway where T1 contributor is not efficaciously anesthetized, respectively in 40% 1 and 32% 5 of cases.
Karl Otto Geier, M.D.
Dear editor, we thanked the interest demonstrated by M.D. Geier to our work. We believe that the contributions accomplished by him are extremely relevant. In our point of view, the designation of interscalenic brachial plexus block by posterior pathways seems more correct, although denominations as brachial plexus block by posterior pathway or cervical paravertebral block are also correct. M.D. Geier's comment on the dispersion of local anesthetic is correct for the cases mentioned. If there is systematic repetition of this pattern, we cannot affirm based on the work carried out. The confirmation of this assertive must be object of subsequent studies.
Cunha Cruvinel, TSA, M.D.
Carlos Henrique Viana de Castro, TSA, M.D.
Yerkes P. Silva, M.D.
Flávio Lago, M.D.
Flávio França, M.D.
01. Cruvinel MGC, Castro CHV, Silva YP et al Estudo radiológico da dispersão de diferentes volumes de anestésico local no bloqueio de plexo branquial pela via posterior. Rev Bras Anestesiol, 2005;55:508-516.
02. Kappis M Ueber leitungsanästhesie an bauch, brust, arm und hals durch injektion aus foramen intervertebrale. Muenchener Medizinische Wochenschrift 1912;15:794-796.
03. Pippa P, Cominelli E, Marinelli C et al Brachial plexus block using the posterior approach. Eur J Anaesthesiol, 1990;7:411-420
04. Dagli G, Guzeldemir ME, Acar HV The effects and side effects of interscalene brachial plexus block by posterior approach. Reg Anesth Pain Med, 1998;23:87-91.
05. Sandefo I, Iohom G, Elstraete AV et al - Clinical efficacy of the brachial plexus block via the posterior approach. Reg Anesth Pain Med, 2005;30:238-242.