Anesthetic implications of Intraoperative Trigemino - Cardiac Reflex: A Systematic Literature Review

Trigemino cardiac reflex (TCR) is a sudden physiological response due to the pressure effect, stretching or any stimulus of the largest cranial nerve, the trigeminal nerve (cranial nerve v).TCR is actually an endogenous physiological protective mechanisms found in brain against ischemia.It is one of the oxygen conserving reflexes.Within seconds of initiation of such reflex, there is activation of sympathetic nerves which leads to cerebrovascular vasodilatation.These responses are sometimes exaggerated and put the patient at risk. During the initial period of vagal stimulation, the cardiac depression occurs leading to sinus arrest, asystole or VF Trigemino cardiac reflex (TCR) is a powerful brainstem reflex that manifests as sudden onset of hemodynamic instability with fall in blood pressure, heart rate, apnea and gastric hyper motility during stimulation of any branches of the Trigeminal nerve. This is one reflex that can catch the anesthesiologist off guard on a busy day leading to catastrophic situation intra operatively with bradycardia and asystole hence the need to revisit and review current literature to keep young Anesthesiologists aware and on guard for this reflex. Objectives: 1) Identify the anatomical structures involved 2) Describe the triggers risk factors 3) Review the management of a patient with TCR. 4) Outline strategies for improving early detection and management to improve outcomes.