Efficacy of three different doses of Fentanyl Citrate for attenuation of hemodynamic stress response to Laryngoscopy and Endotracheal Intubation in surgeries under General Anaesthesia - A Randomised Comparative Study.

Securing the airway is an essential component of anaesthesia care for patients undergoing surgeries under General Anaesthesia. Laryngoscopy and Endotracheal Intubation are core integral components of anaesthetic management under General Anaesthesia but these are associated with reflex cardiovascular responses mediated by sympathetic nervous system by stimulating sympathoadrenal receptors releasing catecholamines in the blood thus transiently causing tachycardia, hypertension, arrhythmias and raised intraocular and intracranial       pressures. Such pressor responses are well tolerated in healthy individuals but are hazardous in patients suffering from coronary artery disease, hypertension, valvular heart disease, stroke, intracranial lesions and penetrating eye injuries.

Several measures have been shown for attenuation of hemodynamic stress response to laryngoscopy and Endotracheal intubation including deepening the plane of anaesthesia, limiting the duration of Laryngoscopy for <30 seconds, various pharmacological measures such as Opioids like Fentanyl ,Vasodilators, Beta Blockers( selective and non selective), Calcium channel blockers, Lignocaine , Magnesium Sulphate etc. Among these, Fentanyl belongs to the phenylpiperidine group of synthetic opioids and is a opioid agonist at Âµ1 and Âµ 2 receptors with rapid onset of action peak of about 5 mins and rapid termination of its effects after a single dose and the occurrence of relative cardiovascular stability and has been shown to effectively attenuate hemodynamic stress response to Laryngoscopy and Endotracheal intubation. Fentanyl decreases the heart rate by increasing Vagal tone by stimulating Vagal nuclei in the medulla thereby, preventing hemodynamic stress response to Laryngoscopy and Endotracheal Intubation .

          It also dilates arterial and venous blood vessels through a central mechanism,by primarily slowing down vasomotor centers in the brain. Recent assays in man show no clinically significant histamine release in dosages up to 50mcg/kg. Total moderate dose of Fentanyl Citrate in adults for General anaesthesia is 2-20mcg/kg.

We devised this study to evaluate the efficacy of three different doses of Fentanyl Citrate for

attenuation of hemodynamic stress response to Laryngoscopy and Endotracheal Intubation.