Pharmacology - Clinical Scenario: The importance of homeostasis through ANS manipulation
A patient undergoing a general anesthesia for eye surgery is intubated with direct laryngoscopy (Figure 1) which can stimulate the sympathetic nervous system (SNS) to cause significant increase in blood pressure. However, fentanyl is used prior to direct laryngoscopy to blunt the activation of the SNS, therefore maintaining ANS homeostasis. Conversely, traction on the eyeball during surgery can activate the parasympathetic nervous system (PNS) via the ocular-cardiac reflex to cause significant bradycardia. Atropine, an anti-muscarinic agent, is used to blunt the activation of the PNS, therefore preventing bradycardia.
