Clinical Efficacy Of Combination Of Diltiazem And Lidocaine In Attenuating Hemodynamic Changes During Tracheal Intubation And Comparing The Response When They Are Used Alone.

摘要

Background: Tracheal intubation produces transient hemodynamic pressor responses which may be unpredictable. Diltiazem-lidocaine combination is hypothesized to attenuate these responses better that when they are used alone.Aims: To compare the clinical efficacy and safety of diltiazem-lidocaine combination in attenuating pressor response to tracheal intubation with lidocaine and diltiazem alone.Settings and Design : prospective double blind, randomised clinical trial of efficacy and safetyMethods and Materials: 120 ASA grade I&II patients were randomly divided in to four groups (using a random sequence generator) of 30 each according to the drug given before intubation to attenuate the hemodynamic response to intubation: saline in control group, diltiazem in D group, lidocaine in L group and both diltiazem and lidocaine in DL group. The person A prepared the drugs, B injected the drug and C evaluated the response; B and C were thus unaware of the drug given.Statistical analysis used : Demographic profiles were evaluated statistically using CHI square test. Changes in haemodynamic parameters were compared using paired t test within the group. Inter group comparison were done by one way analysis of variance (ANOVA). Results: The attenuation of hemodynamic response occurred maximal in DL group followed by lidocaine and diltiazem group respectively ( P value< 0.001 till 5 minutes postintubation for BP and HR). Lidocaine controlled both heart rate and blood pressure better than Diltiazem as there was reflex tachycardia to some extent in D group due to reflex sympathoadrenal stimulation. Diltiazem-Lidocaine combination controlled both these parameter to optimal levels.Conclusions : The primary outcome of the study is that Diltiazem-Lidocaine combination is safe and effective in attenuating pressor response to tracheal intubation . We recommend its routine used before intubation Introduction The peri-intubation period is one of the moments of most stress during general anaesthesia. Laryngoscopy and tracheal intubation is invariably associated with certain haemodynamic and cardiovascular changes such as transient hypertension, tachycardia which may result in wide variety of cardiac arrhythmias. These changes are usually transitory but variable and unpredictable1. Many methods have been devised to reduce the extent of such haemodynamic events during intubation. Some of them like deep level of anaesthesia, use of beta blockers and agents like phentolamine, sodium nitroprusside and nitroglycerine are effective but requires continuous intraarterial monitoring. 2,3,4 Lidocaine has been used for attenuation of cardiovascular responses to intubation since a long time.5 Its acts by inhibiting sodium channels in the neuronal cell membrane, decreasing the sensitivity of the heart muscles to the electrical impulses, has direct cardiac depression and peripheral vasodilatation properties. It also suppress airway reflexes and its analgesic as well as anti-arrythmic properties .6 Diltiazem also attenuates the cardiovascular response to intubation by blocking voltage sensitive L type channels and inhibiting calcium entry mediated action potential in smooth and cardiac muscle cell. It also controls hypertension by its peripheral vasodilating action.7 Because the pharmacological mechanism of action is different for diltiazem and lidocaine, a combination of these two drugs is hypothesized to be more effective than each drug used alone for attenuation of cardiovascular response to intubation .7,8 Methods This prospective double blind randomized study was conducted over a period extending from august 2009 to august 2011 after obtaining approval of institutional ethics committee. 120 patients, ASA physical status I /II , aged 18-65 years ,of either sex undergoing elective surgery under general anaesthesia were selected for this study. Informed consent was taken from all the patients. Patients with ASA grade more than II, history of hypertension, diabetes,