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Year : 2013  |  Volume : 7  |  Issue : 1  |  Page : 83-88  

Comparison of esmolol and lidocaine for attenuation of cardiovascular stress response to laryngoscopy and endotracheal intubation in a Ghanaian population

1 Department of Anaesthesia and Intensive Care, School of Medical Sciences, College of Health Sciences, Kumasi, Ghana, West Africa
2 Department of Molecular Medicine, School of Medical Sciences, College of Health Sciences, Kumasi, West Africa
3 University Health Services, Kwame Nkrumah University of Science and Technology, Kumasi, West Africa

Date of Web Publication26-Jun-2013

Correspondence Address:
Sanjeev Singh
Department of Anaesthesia and Intensive Care, School of Medical Sciences, College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana, West Africa

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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0259-1162.114008

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Background: Direct laryngoscopy and endotracheal intubation always trigger powerful cardiovascular responses. Various attempts have been made to attenuate these responses. The aim of this study was to compare the efficacy and safety of esmolol and lidocaine for suppressing cardiovascular response to laryngoscopy and tracheal intubation in a normotensive African population.
Materials and Methods: A randomized controlled trial was conducted in 120 adult patients of American Society of Anaesthesiologists (ASA) physical status I or II undergoing various elective surgeries. The patients were randomly divided into three groups of 40 patients in each group - C, L, and E. Group - "C" received no drug (control) as placebo, group -"L" received 1.5 mg kg -1 preservative free lidocaine and group -"E" received 2 mg kg -1 esmolol IV 2 min before intubation. Mean arterial pressure (MAP) and rate-pressure product (RPP) were measured before induction as baseline and after tracheal intubation at minute 1, 3, and 5. The patients were randomly allocated to receive either saline (Group C), lidocaine 1.5 mg/kg (Group L), or esmolol 2 mg/kg (Group E) (n = 40, each group). After induction of general anesthesia with thiopental 6 mg/kg and vecuronium 0.12 mg/kg, the test solution was infused 2 min before tracheal intubation. Changes in heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial blood pressure (MAP), and rate-pressure product (RPP) were measured before induction of general anesthesia (baseline), 1, 3, and 5 min after tracheal intubation. Patients were also observed for any complications.
Results: There was a significant increase in HR, SBP, DBP, MAP, and RPP from the base line in control group "C" at 1 min with onward decreases at 3 and 5 min respectively after intubation. Percentage change in hemodynamic variables in groups C, L, and E at 1 min are as follows: HR = 30.45, 26.00, and 1.50%; MAP = 20.80, 15.89, and 10.20%; RPP = 61.44, 40.86, and 11.68%, respectively. Only patients receiving placebo had increased HR, MAP, and RPP values after intubation compared with baseline values (P < 0.05).
Conclusions: Prophylactic therapy with 2 mg kg -1 esmolol is more effective and safe for attenuating cardiovascular responses to laryngoscopy and tracheal intubation in a black population.

Keywords: Blood pressure, esmolol, lidocaine, heart rate, intubation, laryngoscopy, Ghana (Source: MeSH, NLM)

How to cite this article:
Singh S, Laing EF, Ansah Owiredu WB, Singh A. Comparison of esmolol and lidocaine for attenuation of cardiovascular stress response to laryngoscopy and endotracheal intubation in a Ghanaian population. Anesth Essays Res 2013;7:83-8

How to cite this URL:
Singh S, Laing EF, Ansah Owiredu WB, Singh A. Comparison of esmolol and lidocaine for attenuation of cardiovascular stress response to laryngoscopy and endotracheal intubation in a Ghanaian population. Anesth Essays Res [serial online] 2013 [cited 2022 May 19];7:83-8. Available from:

   Introduction Top

Cardiovascular complications are one of the most common causes of anesthesia-related morbidity and mortality. [1] Direct laryngoscopy and endotracheal intubation frequently induces a cardiovascular stress response characterized by hypertension and tachycardia due to reflex sympathetic simulation. The response is transient occurring 30 sec after intubation and lasting for less than 10 min. [2] It may be well tolerated in healthy people, but may be hazardous in patients with hypertension, tachycardia, myocardial infarction, and other complications. [3] Various pharmacological approaches have been used to attenuate the pressure responses to laryngoscopy and tracheal intubation. [4]

Specific racial differences need to be considered before treatment as it was found that African-Americans respond less well to beta adrenergic receptor blocking drugs as whites do. [5] The present work was undertaken to compare the effect of lidocaine and esmolol on blunting the hemodynamic responses to endotracheal intubation in normotenseive black patients.

Perioperative myocardial infarction is a leading cause of postoperative morbidity and mortality due to hypertension and tachycardia. [1] Studies from the African continent report avoidable anesthesia mortality rates of 1:1900 in Zambia, [6] 1:500 in Malawi [7] and 1:150 in Togo. [8] Such anesthesia-related deaths could be reduced by controlling the hemodynamic changes that occur due to myocardial ischemia. There is increasing evidence that the control of the heart rate and blood pressure response to endotracheal intubation is essential in preventing adverse cardiovascular outcomes, as rate pressure product (RPP) acts as an indicator of oxygen demand by the heart at the onset of ischemia, [9] there is therefore a need for assessment in this direction as there are currently no available studies in the Ghanaian population on the efficacy of lidocaine and esmolol in attenuating hemodynamic responses during intubation. Efforts are being made in Ghana to practice safe anesthesia and reduce perioperative complications and mortality during anesthesia. The purpose of this study was to determine the efficacy and safety of intravenous lidocaine and esmolol in attenuating hemodynamic response to laryngoscopy and intubation in a Ghanaian population.

   Materials and Methods Top

This study was undertaken after an institutional approval by the Committee on Human Research Publications and Ethics was obtained. The study was conducted from November 2011 to May 2012. Informed consent was obtained from 120 patients. The study population consisted of ASA physical status I or II, male and female adults between the ages of 18-65 years scheduled for various elective surgical procedures.

Study design

This study was a prospective, randomized, and double blinded clinical comparison study in a Black population. The Sample size for the study was 120 generated using a sample size calculator. The study participants were randomly divided into three groups by a computer generated randomization table. A study nurse (Person A) who was not involved in the randomization process prepared the study drugs, all of which were diluted to 10 milliliters. All three drugs were coded to enhance blinding. Person B monitored the heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) with respect to time whilst Person C was responsible for intubation of the patients. Person A and C were kept constant throughout the study. Person B, C, and the patient were kept unaware of the drug injected to enable double-blinding.

Inclusion criteria

For the study were ASA class I or II, age range 18-65, oropharyngeal anatomy of Mallampati class I and any operation other than cardiac surgery performed under general anesthesia with endotracheal intubation.

Exclusion criteria

For the study included patients who were morbidly obese, patients with cardiovascular disease, heart rate < 60 beats per minute (bpm), basal SBP < 100 mm Hg and other conditions such as bronchial asthma, diabetes mellitus, drug allergies, and total duration of laryngoscopy was noted and in cases where duration exceeded 15 sec was excluded from study.

Pre-surgical protocol

The day prior to surgery all patients underwent a pre-anesthetic evaluation with special consideration to elicit a history of hypertension, dyspnoea, chest pain, cough, wheezing, convulsions, and diabetes mellitus as well as previous anesthetic history and drug sensitivity. Information collected also included weight, nutritional status, airway assessment by the Mallampatti scoring system, a detailed examination of the respiratory, cardiovascular, and central nervous system. A preoperative routine investigations such as hemoglobin, hematocrit, total lymphocyte count, differential lymphocyte count, serum electrolytes, blood group/Rh typing, blood urea nitrogen, serum creatinine, fasting blood sugar, chest radiography, and electro-cardiogram in all patients. Patients were advised to fast the night prior to surgery.

Surgical protocol

After patient identification a short preoperative history was taken, clinical examination and routine investigations were rechecked in all patients. Study objective and procedure were explained to the participants and a written informed consent was obtained from each participant.

Intravenous access was secured and infusion of Ringer's lactate solution started. The patients were pre-medicated with 0.008 mg kg -1 glycopyrrolate-bromide intramuscularly 30 min prior to surgery. Patients were then shifted to the operating room after which routine non-invasive monitor Infinity Delta XL Drager was applied and vital signs monitored. Midazolam 0.04 mg kg -1 was administered intravenously over 30 sec as premedication and patients were pre-oxygenated with four to five breaths of 100% oxygen. The patients were induced with 6 mg kg -1 IV thiopentone sodium in incremental doses until loss of eyelash reflex occurred, 0.12 mg kg -1 IV vecuronium bromide was given over 20 sec, followed up by administering the study drugs (normal saline, esmolol, or lignocaine) 2 min before laryngoscopy and intubation.

The study drug was randomly allocated to patients in a double blinded manner. Patients were ventilated with oxygen and 1% halothane using IPPV with a fresh gas flow of 6 litres min -1 by Bain circuit until intubation. About 2 min after IV vecuronium, laryngoscopy was performed with a Macintosh laryngoscope blade and trachea intubated with an appropriate size cuffed endotracheal tube. After confirmation of correct placement of ET tube, anesthesia was then maintained with O 2 and halothane.

HR, SBP, DBP, MAP, RPP (rate pressure product), SpO 2 (oxygen saturation), and ECG (electrocardiogram) changes were recorded before induction (Basal) and after tracheal intubation at 1, 3, and 5 min for the purpose of this study. No manipulation like painting and draping the area of operation was allowed till 10 min after the study drug administration. Injection fentanyl 2 μg kg -1 was given before surgery.

Parameters and statistical analysis

Summary statistics of patient gender, age, and weight for all three groups were reported as means ± standard deviation. HR, SBP, DBP, and MAP were recorded using Infinity Delta XL Drager, Draeger Medical Systems, Inc. Telford, PA 18969, USA, before induction (Baseline), after tracheal intubation at 1, 3, and 5 min during monitoring. From the data RPP was calculated by multiplying heart rate with systolic blood pressure. Patients were also observed for complications like hypotension, hypertension, arrhythmias, and hypoxemia. Statistical analysis was done by student t-test and P values were calculated. Hemodynamic variables were represented by mean ± SD. ANOVA with repeated measures was used to compare the changes in HR, MAP, and RPP values. Bonferroni's multiple comparison test was applied to evaluate intra group comparisons. The statistical package SPSS; 17.0 and Graphpad prism 5 was used. P 0<0.05, P < 0.001 were considered significant and highly significant, respectively, for the study.

   Results Top

All the demographic profiles in the group C-control, group-L-lignocaine, and group-E-esmolol were comparable [Table 1]. The male to female ratio of group-C was 1:2.64 whereas groups-L and E were 1:1.22 and 1:1.5 (P0 = 0.25), respectively. The average age of the control group was 41.78 ± 12.73 whereas group-L and E were 41.98 ± 13.82 and 40.80 ± 13.71, respectively (P = 0.91). The average weight were 69.68 ± 9.80, 72.00 ± 9.32, and 70.10 ± 9.64 in groups-C, L, and E, respectively ( P = 0.52). The average height in group-C was 163.30 ± 4.64 and groups L and E were 164.00 ± 4.52 and 164.20 ± 5.39 [[ P = 0.73; [Table 1].
Table 1: Distribution of patient's demographic profile

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An increase in HR, MAP, and RPP from the base line and maximum at 1 min after intubation was observed in group-C, however in the groups-L and E there was no significant variation of HR, MAP, and RPP from the base line after 1 min of intubation [Table 2].
Table 2: Changes in hemodynamic variables in control and experimental groups

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In groups C, L, and E maximum increase in mean heart rate over the baseline values were 89.00 ± 9.27, 87.30 ± 9.31, and 90.80 ± 8.59, respectively, and at 1 minute was 116.10 ± 7.62, 110.00 ± 4.93, and 92.20 ± 9.74 after intubation, respectively. The difference between means from baseline value and 1 minute were 27.10 bpm, 22.70 bpm, and 1.40 bpm in groups-C, L, and E, respectively. The mean difference in the heart rate between groups C-L, C-E, and L-E recorded at 1 minute were 6.08, 23.88, and 17.80 bpm [ P < 0.0001] [Table 3].
Table 3: Difference between the mean hemodynamic variables control group compared with experimental groups

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The MAP was increased in group-C as compared to groups-L and E following laryngoscopy and intubation. The maximum increase in MAP over the baseline values (97.08 ± 5.02, 97.16 ± 4.39, and 96.33 ± 4.33) in the groups C, L, and E were recorded at 1 minute (117.3 ± 5.90, 112.6 ± 4.40, and 106.10 ± 4.98) after intubation. The baseline and 1 minute difference were 20.22 mm Hg in group-C, 15.44 mmHg in group-L, and 9.77 mmHg in group-E, with a mean difference between groups C-L, C-E, and L-E 4.73, 11.19, and 6.46 mmHg at 1 minute with P < 0.0001 [Table 3].

There was marked elevation of rate pressure product in group-C as compared to groups-L and E after laryngoscopy and intubation with baseline values 11012 ± 1196, 10975 ± 1304, and 11355 ± 1229, respectively. One minute values of groups-C, L, and E were 17778 ± 1926, 15459 ± 1076, and 12681 ± 1605, respectively. Maximum elevations of mean RPP in the groups were recorded at 1 minute after intubation as follows: 6766, 4484, and 1326 in groups-C, L, and E, respectively. Mean difference between the groups C-L, C-E, and L-E at 1 minute were 2319, 5097, and 2778 [ P < 0.0001] [Table 3].

In all three groups the vitals remained attenuated for 3 min after intubation; however, the vitals returned to baseline values after 5 min. Control group patients undergoing laryngoscopy and intubation showed an incidence of 8% ventricular ectopics and 5% dropped beats however no such findings were recorded in the lignocaine and esmolol groups.

   Discussion Top

The ethnic differences in the pathophysiology and management of hypertensive disease are particularly pertinent to the Afro-Caribbean populations. Beta-blockers are generally less effective in black hypertensives as a result of the tendency toward a low-renin state and with increased peripheral resistance. Higher doses of beta-blockers are therefore required to achieve target blood pressures in Black populations. [10] ί-blocker esmolol possesses several properties which make it a valuable agent to obtund the cardiovascular response. Firstly, it is a cardio selective agent, and secondly it has ultra short duration of action (9 min) [11] and finally, significant drug interaction with commonly used anesthetics has not been reported. [12] Korpinen et al. (1998) reported that the administration of esmolol bolus 2 mg kg -1 IV 2 min before laryngoscopy and intubation suppressed the increase in the heart rate rather than arterial blood pressures. [13] Bostana and Eroglu (2012) reported that IV esmolol in dose of 1 mg kg -1 before intubation was effective in suppressing the heart rate and arterial blood pressure. [14] Kumar et al. (2003) have also claimed optimal results while using higher doses of esmolol in Asian population, i.e., 2 mg kg -1 without any incidence of unplanned hypotension or bradycardia. However, no consensus has been reached regarding the optimum dose and timing of its delivery. [15]

Lidocaine has been a popular agent for attenuating circulatory responses. The beneficial effect of lidocaine is due to its direct cardiac depression and peripheral vasodilation, [16] its ability to suppress airway reflexes elicited by irritation of tracheal mucosa and its analgesic as well as antiarrythmia properties. Some studies have reported beneficial effects [17] while others showed no effect of intravenous lignocaine administered 1, 2, or 3 min before laryngescopy. [18],[19]

The hemodynamic changes in HR, MAP, and RPP from baseline values 1 min after tracheal intubation, in esmolol group were highly significantly less than those in lidocaine. Our failure to detect any significant effect of lidocaine as compared to esmolol on stress response could be due to the fact that we performed this study in patients without heart disease while Stoelting et al. included patients with heart disease and reported a favorable response. [20] Studies have shown that there is increased incidence of myocardial infarction when intraoperative heart rates are more than110 beats min -1 . [21] In our study none of the patients in study groups showed heart rate >110 beats min -1 .

RPP is a good estimate of myocardial oxygen requirement. The RPP levels close to 20,000 are normally associated with angina and myocardial ischemia. [22] RPP 1 min after intubation remained less than 20,000 in study drug groups. This finding confirms the cardio-protective effect of study drugs during laryngoscopy and intubation.

In conclusion, the present data suggest that lidocaine 1.5 mg kg -1 when injected 2 min before intubation can blunt the cardiovascular responses to laryngoscopy and tracheal intubation successfully. However, the prophylactic therapy with esmolol 2 mg kg -1 when injected 2 min before intubation is significantly more effective than lidocaine in suppressing hemodynamic changes to laryngoscopy and tracheal intubation in normotensive black patients. The dosage and timing of administration of drugs are important factors that determine whether they will have beneficial effect on the laryngoscopy and tracheal intubation, therefore further research is necessary to elucidate the effects of different doses of esmolol in black population.

   Conclusion Top

Intravenous lidocaine (1.5 mg kg -1 ) and esmolol (2 mg kg -1 ) are effective agents in suppressing the hemodynamic response to laryngoscopy and intubation without any deleterious effect. Esmolol 2 mg kg -1 appears to be very effective and should be viewed as potential treatment strategy for attenuating hemodynamic changes during induction of anesthesia in Ghanaian population.

   References Top

1.Savio KH, Tait G, Karkouti K, Wijeysundera D, McCluskey S, Beattie WS. The safety of perioperative esmolol: A systematic review and meta-analysis of randomized controlled trials. Anesth Analg 2011;112:267-81.  Back to cited text no. 1
2.Gupta A, Wakhloo R, Gupta V, Mehta A, Kapoor BB. Comparison of Esmolol and Lignocaine for attenuation of cardiovascular stress response to laryngoscopy and endotracheal intubation. JK Science 2009;11:78-81.  Back to cited text no. 2
3.Manjunath HG, Venkatesh GS, Prima V, Jennifer LV, Sathees BC. Can calcium and sodium channel blockers attenuate hemodynamic responses to endotracheal intubation? Eur J Gen Med 2008;5:198-207.  Back to cited text no. 3
4.Rupakar VB, Raval B, Chadha IA. Attenuation of cardiovascular responses to laryngoscopy and endotracheal intubation with diltiazem-lignocaine combination. J Anaesthesiol Clin Pharmacol 2009;25:341-4.  Back to cited text no. 4
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5.Materson BJ, Reda DJ, Cushman WC. Single-drug therapy for hypertension in men. A comparison of six antihypertensive agents with placebo. N Engl J Med 1993;328:914-21.  Back to cited text no. 5
6.Heywood AJ, Wilson IH, Sinclair JR. Perioperative mortality in Zambia. Ann R Coll Surg Engl 1989;71:354-8.  Back to cited text no. 6
7.Hansen D, Gausi SC, Merikebu M. Anaesthesia in Malawi: Complications and deaths. Trop Doct 2000;30:146-9.  Back to cited text no. 7
8.Bang'na Maman AF, Tomta K, Ahouangbevi S. Deaths associated with anaesthesia in Togo, West Africa. Trop Doct 2005;35:220-2.  Back to cited text no. 8
9.Figueredo E, Garcia EM. Assessment of the efficacy of esmolol on the hemodynamic changes induced by laryngoscopy and tracheal intubation: A meta analysis. Acta Anaesthesiol Scand 2004;45:1011-22.  Back to cited text no. 9
10.Gibbs CR, Beevers DG, Lip GY. The management of hypertensive disease in Black patients. QJM 1999;92:187-92.  Back to cited text no. 10
11.Kumar S, Mishra MN, Mishra LS, Bathla S. Comparative study of the efficacy of i.v. esmolol, diltiazem and magnesium sulphate in attenuating haemodynamic response to laryngoscopy and tracheal intubation. Indian J Anaesth 2003;47:41-4.  Back to cited text no. 11
12.Vucevic M, Purdy GM, Ellis FR. Esmolol hydrochloride for management of the cardiovascular stress responses to larngoscopy and tracheal intubation. Br J Anaesth 1992;68:529-30.  Back to cited text no. 12
13.Korpinen R, Simola M, Saarnivaara L. Effect of esmolol on the hemodynamic and electrocardiographic changes during laryngomicroscopy under propofol-alfentanil anesthesia. Acta Anaesthesiol Belg 1998;49:123-32.  Back to cited text no. 13
14.Bostana H, Eroglu A. Comparison of the clinical efficacies of fentanyl, esmolol and lidocaine in preventing the hemodynamic responses to endotracheal intubation and extubation. J Curr Surg 2012;2:24-8.  Back to cited text no. 14
15.Shroff PP, Mohite SN, Panchal ID. Bolus administration of esmolol in controlling the haemodynamic response to tracheal intubation. J Anaesthesiol Clin Pharmacol 2004;20:69-72.  Back to cited text no. 15
16.Abou-Madi M, Keszler H, Yacoub JM. Cardiovascular reactions to laryngoscopy and tracheal intubation following small and large intravenous dose of lidocaine. Can J Anaesth 1977;24:12-9.  Back to cited text no. 16
17.Pandey CK, Raza M, Ranjan R. Intravenous lidocaine suppresses fentanyl-induced coughing: A double-blind, prospective, randomized placebo-controlled study. Anesth Analg 2004;99:1696-8.  Back to cited text no. 17
18.Miller CD, Warren SJ. Intravenous lignocaine fails to attenuate the cardiovascular response to laryngoscopy and tracheal intubation. Br J Anaesth 1990;65:216-9.  Back to cited text no. 18
19.Jolliffe CT, Leece EA, Adams V, Marlin DJ. Effect of intravenous lidocaine on heart rate, systolic arterial blood pressure and cough responses to endotracheal intubation in propofol-anaesthetized dogs. Vet Anaesth Analg 2007;34:322-30.  Back to cited text no. 19
20.Stoelting RK. Circulatory changes during direct laryngoscopy and tracheal intubation: Influence of duration of laryngoscopy with or without prior lidocaine. Anesthesiology 1977;47:381-3.  Back to cited text no. 20
21.Tian-long W, Yan J, Ba-xian Y. Effect of nicardipine combined with esmolol on systemic and tissue oxygenation during off-pump coronary artery bypass grafting surgery. Chin Med J 2005;118:130-5.  Back to cited text no. 21
22.Elif BS, Emre U, Burcu U, Binnur S. Hemodynamic responses and upper airway morbidity following tracheal intubation in patients with hypertension: Conventional laryngoscopy versus an intubating laryngeal mask airway. Clinics 2012;67:49-54.  Back to cited text no. 22


  [Table 1], [Table 2], [Table 3]

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