A Comparative Study of Intravenous Nitroglycerin With or Without Intravenous Lignocaine for Attenuation of Stress Responses to Endotracheal Intubation

Abstract

Background: Laryngoscopy and tracheal intubation lead to stress response which is characterized by transient rise in blood pressure and heart rate. This response is tolerated well in normal individuals but can lead to significant morbidity and mortality in patients with cardiovascular and cerebrovascular diseases. Search for the better drugs to suppress these responses is going on through decades.
 Aim of Study: To compare the effects of IV nitroglycerin alone and in combination with IV lignocaine, on attenuation of stress response to end tracheal intubation.
 Material and Methods: This is a randomized, double blind study conducted in 60patients admitted for operation at NGMCTH, between June 2018 to November 2018. Patients were of 16- 60 years age groups and belonging to ASA group I and II. Patients were divided into two groups: Group I IV Nitroglycerin 500 mcg+ NS 3 ml. (n=30) and Group IIIV Nitroglycerin 500 mcg+ IV Lignocaine 63 mg (n=30). Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP), Mean Arterial Pressure (MAP) and Heart rate (HR) were measured and Rate Pressure Product (RPP) calculated.
 Results: Baseline values were comparable in both groups. Post Intubation, there was significant decrease in SBP at 0,1,3 and 5 minutes while DBP and MAP significantly decreased at 1, 3 and 5 minutes, in both groups. Significant tachycardia was noted in both groups at 0,1and 3 minutes, and RPP remained unchanged in both groups.
 Conclusion: Nitroglycerin significantly decreases blood pressure, prevents rise in RPP but does not attenuate heart rate after end tracheal intubation. There is no benefit of adding IV lignocaine to IV nitroglycerin for attenuation of stress response to end tracheal intubation.

Blunting Stress Response During Intubation in Hypertensive Patients; A Comparison Between Lidocaine and Magnesium Sulphate

“…It can also lead to cerebrovascular accidents in hypertensive patients with cerebrovascular disease. 12 Various drug including β-blockers such as Labetalol, 13 and Esmolol, 14 Opioids, Lidocaine, 15,16 Nitroglycerine, alpha adrenergic agonists such as Clonidine, 17 and dexmedetomidine, 17 calcium channel blockers such as Diltiazem, 18 and have been used for obtunding the stress response. Lidocaine, whether given intravenously or through an endotracheal tube, successfully prevents the rise in blood pressure but fails to prevent the rise in heart rate.…”

Comparison of the Effects of Nitroglycerin, Labetalol and Lidocaine in Hypertensive Patients in Attenuation of the Endotracheal Intubation Reflex

“…15,16 Regmi & Singh observed that nitroglycerine significantly decreases blood pressure, prevents rise in RPP but does not attenuate heart rate after endotracheal intubation. 17 These can be explained by difference in induction drugs, e.g., Mikawa et al used IM atropine 0.01 mg/kg as premedication which could induce tachycardia, 15 while Grover et al used glycopyrrolate 0.2 mg in all patient which could slightly rise the heart rate. 16 Both the studies used vecuronium to facilitate tracheal intubation, whereas in our study, we used succinylcholine 1.5 mg/kg which is a known drug that can cause bradycardia.…”

“…19 In our study systolic blood pressure was significantly lower in group A at 0 minute and 1 15 Regmi & Singh showed nitroglycerin significantly decreases blood pressure, prevents rise of rate pressure product (RPP), but does not attenuate heart rate after endotracheal intubation. 17 Singh et al reported that i.v. lidocaine 1.5 mg/kg is also an effective agent in suppressing hemodynamic response to laryngoscopy and intubation without any deleterious effect.…”