Splanchnic nerve block

In tumors involving the lower third of the mediastinum, it is necessary to block the splanchnic nerves which contribute an important sensory nerve supply to the lower third of the intrathoracic part and the abdominal portion of the esophagus. The other indications are similar to those for celiac plexus block and splanchnic nerve block is preferred to celiac block in cases with large infiltration and invasion of periaortic space. The splanchnic nerve block requires a smaller volume of alcohol (Bonica 1990b Kurdziel and Dondelinger 1990 Herpels et al. 1988 Crespy et al. 1984 Lillemoe et al. 1993). 

With the use of celiac plexus or splanchnic nerve block, between 70% and 85% of patients with severe abdominal cancer pain obtained pain relief lasting from 1 month up to 1 year (Bonica 1990b). The most frequent complication with celiac plexus block is orthostatic arterial hypotension (Lema et al. 1992 Kurdziel and Dondelinger 1990 Schild 1998 Whitemann et al. 1986 Pateman et al. 1990 Lee et al. 1993 Herpels et al. 1988 Haaga et al. 1984 Fujita and Takaori 1987). 

In splanchnic nerve block, complications like orthostatic arterial hypotension are unusual because the procedure is less likely to involve the lumbar sympathetic chain than with celiac plexus block. Pneumothorax, intrathecal, and intravascular injection can be avoided under precise CT guidance (Kurdziel and Dondelinger 1990). 

Gaudy JH, Tricot C, Sezeur A. Troubles du rythme cardiaque graves apres phenoUsation splanchnique peroperatoire. [Serious heart rate disorders following perioperative splanchnic nerve phenol nerve block.] Can J Anaesth 1993 40(4) 357-9. 

Kitamura et al. [63] have studied the effects of co-conotoxin GVIA and L-type Ca channel blockers (nifedipine and verapamil) on catecholamine release in anesthetized dogs. Catecholamine release into the blood stream was induced either by electrical stimulation of the splanchnic nerve or by intra-arterial injection of acetylcholine. Administration of 0.4 pg/mL of co-conotoxin GVIA reduced catecholamine secretion by 30% in response to the electrical stimulation nifedipine or verapamil had no effect under these experimental conditions. However, when catecholamine release was induced by acetylcholine, co-conotoxin GVIA blocked secretion by around 50% and nifedipine also reduced it by 50%. These results suggest that N- and L-type Ca channels contribute to the release of catecholamines in the dog adrenal gland. To our knowledge, a patch-clamp study that determines the subtypes of Ca channels expressed by dog chromaffin cells is not available. 

Neurolytic Block of the Celiac Plexus and Splanchnic Nerves... 

Under CT guidance, a 22-gauge needle is inserted into the retrocrural space at the level of T11-T12 by a posterior percutaneous approach. The needle tip is located just lateral to the anterolateral surface of the vertebra where the three thoracic splanchnic nerves are located in close proximity to one another (Fig. 11.8). After injection of 2 ml of bupivacaine diluted with contrast medium confirming the location of the needle tip, 10 ml of ethanol (96%) are injected on both sides. A bilateral block is often essential for relief of upper abdominal pain (Bonica 1990b Kurdziel and Dondelinger 1990). 

Hendrickson FR et al (1976) Radiation therapy for osseous metastases. Int J Radiat Oncol Biol Phys 1 275 Herpels V et al (1988) Percutaneous CT guided nerve block of the coeliac plexus and splanchnic nerves. Ann Radiol 31 291-296... 

Rutherford had found that the gastric mucosa of a rabbit became paler after division of the vagus, that upon stimulation of the central ends of the cut vagus it became redder, and that the latter effect was blocked by atropine. Normal secretion, Rutherford thought, occurs after section of the splanchnic nerves central stimulation of the vagus inhibits a vasomotor center, thereby decreasing sympathetic vasoconstrictor influence on the gastric mucosa. Rutherford wrote ... 

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