Letters to the Editor: Letters & Announcements
To the Editor:
Recently, Hatton et al. (1) described a number of side effects of vagal nerve stimulator (VNS) implantation related to vagal efferent control of the gastrointestinal tract via the parasympathetic nervous system.
Dyspepsia occurring in 12.6% can be explained by the action of the vagus nerve, which stimulates increased gastric acid secretion as well as promotes gastric emptying. However, the cause of dyspepsia may be multifactorial resulting from gastric hypersecretion (previously treated surgically with vagotomy and accompanied by pyloroplasty due to the vagotomy causing gastric stasis) or gastroparesis or delayed gastric emptying.
We are writing to illustrate a further effect of the VNS on gastric motility. A gentleman attended our neurosurgical unit for replacement of his VNS battery. He had experienced seizures since childhood; suffering 7–10 episodes each week despite best medical management. VNS was placed in October 2000 resulting in improved seizure control.
The seizures had increased in frequency 7 months before admission for this procedure, and interrogation of the electronics confirmed end of battery life.
Upon routine preoperative anesthetic assessment, we discovered that he had also experienced dyspepsia over these 7 months. Relief was attained by taking a proton pump inhibitor. The gentleman attributed his dyspepsia to VNS failure.
He underwent unremarkable day-case anesthesia and battery replacement. Telephone conversation, 2 weeks later, confirmed that the symptoms of reflux had ceased after reinstitution of VNS.
This demonstrates a gastrointestinal effect of VNS, which was advantageous to our patient. It may be that VNS could offer an alternative solution to dyspepsia resulting from impaired gastric emptying.
Rohna Sinclair, MRCP, FRCA
Specialist Registrar in Anaesthetics
Rahul R. Bajekal, MD, FRCA
Department of Anaesthesia
Newcastle General Hospital
Newcastle Upon Tyne, UK
1. Hatton K, McLarney J, Pitmann T, Fahy B. Vagal nerve stimulation: overview and implications for anesthesiologists. Anesth Analg 2006;103:1241–9