General Anesthesia and Autonomic Nervous System: Control and Management in Neurosurgery

*Irina Alexandrovna Savvina, Anna Olegovna Petrova and Yulia Mikhailovna Zabrodskaya*

### **Abstract**

The chapter is devoted to the control and management of the autonomic nervous system during general anesthesia in neurosurgery. The brainstem and supratentorial cerebral centers of autonomic regulation are the most important structures for control and management during general anesthesia using pharmacological defense with α2-adrenergic agonists and opioid analgesics. We discuss the questions of the depth of anesthesia (BIS-monitoring) and antinociceptive defense, variability of heart rate (variational cardiointervalometry), hemodynamic monitoring during neurosurgical operation, intraoperative thermometry, the meaning of trigeminocardiac reflex and its classification in neurosurgery, perioperative events causing autonomic distress syndrome development and methods of its prophylaxis and treatment, pathomorphological signs of vegetative distress syndrome. Control of the neuromuscular block and photoplethysmography assessment of perfusion index (PI) as methods of the adequacy of general anesthesia and neurovegetative stability.

**Keywords:** general anesthesia, premedication, autonomic nervous system, neurosurgery, brainstem autonomic centers, depth of anesthesia, trigeminocardiac reflex, variability of heart rate, autonomic distress syndrome

### **1. Introduction**

Scientific and clinical interest in the problem of control and management of the autonomic nervous system in various fields of surgery and anesthesiology is due, in our opinion, to the relationship of the initial vegetative status of the patient (tone, reactivity of the ANS) and anesthesia techniques with the peculiarities and complications of the intra- and postoperative period; the development of cardiovascular (cardiac arrhythmias, hemodynamic instability, arterial hypertension), respiratory complications during surgery and in the early postoperative period, the occurrence of postoperative nausea and vomiting (PONV), postoperative delirium (POD), the severity of pain syndrome.

In neurosurgery, the relevance of this problem is due to the participation of autonomous control mechanisms in the autoregulation of cerebral circulation and cerebral vascular tone, which directly affects the intraoperative state of the brain, perfusion pressure of the brain, stability of its volume, and compliance—the most important characteristics reflecting the adequacy of anesthetic provision.

The literature describes prognostic predictors of complications, such as postoperative delirium, with the sympathetic pattern of the autonomic nervous system in otolaryngology surgery [1, 2], the formation of neuropathic pain and postoperative nausea and vomiting with the predominance of parasympathetic influences, etc.

Thus, it is extremely important to take into account the initial version of the tone of the autonomic nervous system. Monitoring and managing the balance and reactivity of the links of the autonomic nervous system during the preparation of the patient for surgery and during the operation and anesthesia itself will allow to obtain a result in the form of reducing the risks of perioperative complications.
