Ain-Shams Journal of Anaesthesiology

: 2014  |  Volume : 7  |  Issue : 4  |  Page : 524--529

Palatal lidocaine gel as an adjuvant to propofol versus propofol only for sedation during upper gastrointestinal tract endoscopy: a comparative study

Mahmoud Ghallab, Rania M Hussien, Ghada M Samir, Dalia A Ibrhaim 
 Department of Anesthesia, ICU and Pain Management, Ain Shams University, Cairo, Egypt

Correspondence Address:
Rania M Hussien
4 Eladeeb Mohamed Elsbaee St, Elmasria Class Buildings, Ramsis Building, 701, Elnozha Algadida, Cairo 11769


Background Lidocaine gel is a palatable preparation of lidocaine 2% that is produced by Amoun Pharmaceutical Co. (Cairo, Egypt). Aim The aim of the study was to evaluate the efficacy of palatable lidocaine gel as an adjuvant to propofol for anesthesia during upper gastrointestinal tract endoscopy in terms of propofol consumption, ease of performance of the procedure, and recovery time. Patients and methods A prospective randomized clinical study was conducted on 100 patients undergoing diagnostic esophagogastroduodenoscopy in Ain Shams University hospitals, who were randomized into two groups of 50 patients each. In the first group (X group), 15 mg of palatable lidocaine gel together with intravenous sedation using propofol was used, whereas in the control group (C group) intravenous sedation with propofol only was given. Measurements in both groups included propofol consumption as well as the incidence of apnea and hypoxia, recovery time, and both endoscopist and patient satisfaction. Results Patients in the palatable lidocaine gel group (X group) tolerated the procedure better than those in the control group (C group). The endoscopists encountered less difficulty performing the procedure in the X group. In addition, propofol consumption and the incidence of apnea and hypoxia were lower in the X group, and recovery time was significantly shorter in the X group. The patients in the X group were more satisfied with the mode of anesthesia they received as compared with patients in the C group. The endoscopists were equally satisfied with the mode of anesthesia in both groups. Conclusion The use of palatable lidocaine gel in esophagogastroduodenoscopy decreases propofol consumption, shortens recovery time, and improves patient comfort and tolerance to the procedure, and also reduces the cost.

How to cite this article:
Ghallab M, Hussien RM, Samir GM, Ibrhaim DA. Palatal lidocaine gel as an adjuvant to propofol versus propofol only for sedation during upper gastrointestinal tract endoscopy: a comparative study.Ain-Shams J Anaesthesiol 2014;7:524-529

How to cite this URL:
Ghallab M, Hussien RM, Samir GM, Ibrhaim DA. Palatal lidocaine gel as an adjuvant to propofol versus propofol only for sedation during upper gastrointestinal tract endoscopy: a comparative study. Ain-Shams J Anaesthesiol [serial online] 2014 [cited 2022 Jan 27 ];7:524-529
Available from:

Full Text


Upper gastrointestinal tract (GIT) endoscopy allows physicians to examine the lining of the upper part of the GIT, including the esophagus, stomach, and duodenum. Upper GIT endoscopy is a valuable diagnostic procedure that determines the causes of upper GIT symptoms - such as pain, bleeding, dysphagia, reflux, and recurrent vomiting - by direct visualization of the GIT mucosal pathology including inflammation, ulcers, and tumors [1,2]. It is the best test for diagnosing, grading, and even ligating varices. Moreover, it is an easy method for taking biopsy samples from suspected areas for confirming diagnosis. It may be performed in unsedated patients; yet, giving sedation or intravenous (i.v.) anesthesia is preferred to ensure patient comfort and convenience. Midazolam, propofol, and fentanyl are the most commonly used i.v. anesthetics that offer sedation, amnesia, and analgesia during the procedure [3].

Upper GIT endoscopy is considered a safe procedure despite a low risk of complications that may be attributed to the procedure itself, including perforation of the GIT or bleeding from an ulcer or varices, or related to increased dose of i.v. anesthetics especially in elderly patients or in those with other comorbidities. These complications include apnea and hypoxia, hypotension, and paradoxical agitation, in which the patient becomes agitated rather than sleepy from the sedation [4]. These complications add to the overall costs by increasing morbidity and the duration of the patient's hospitalization. Therefore, in this study we tried to avoid these complications by decreasing the dose of i.v. anesthetic without reducing the level of patient and endoscopist satisfaction by using topical palatable lidocaine gel [5,6].

Application of lidocaine to the oral cavity and the oropharynx, especially to the base of the tongue, uvula, palate, posterior pharyngeal wall, and palatoglossal and palatopharyngeal folds, will attenuate or even abolish the gag reflex during the introduction of the upper GIT endoscope, increasing the patient's comfort and tolerance to the procedure, thus decreasing the dose of i.v. anesthetics with their potential complications [7,8].

The lidocaine gel used is a palatable preparation of lidocaine 2% produced by Amoun Pharmaceutical Co. (Cairo, Egypt). It is used to prevent pain and discomfort during medical procedures. It is a local anesthetic that stabilizes the neuronal membrane by hindering the ionic fluxes that are necessary for the initiation and transmission of impulses, thereby giving a local anesthetic action. It is applied at the start of the procedure and takes 3-5 min for the numbing effect to occur [9].

Topical lidocaine spray is conventionally used in combination with i.v. anesthetics before the procedure to offer local anesthesia to the oropharynges, thus reducing pain and gagging during introduction of the endoscope; yet, lidocaine spray is not preferred by most patients as it is an irritant and has a sour taste. Other studies used different types of topical anesthetics, including inhaler, spray, lollipop, gel, viscous agents, and lozenges [10,11]. Some of these agents carry the risk of retching and vomiting. The use of the gel form of lidocaine allows the application of a dense layer of lidocaine, which provides better anesthesia for the oral cavity and the oropharynx compared with the spray form. Therefore, the concept of using lidocaine gel (with a very bad taste) as a topical anesthetic in upper endoscopy is not new; yet, the use of the palatable well-tolerated lidocaine gel has not been reported before [12].

Palatable lidocaine gel proved to be a safe and well-tolerated topical anesthetic. It is quite promising and may be particularly important for use in elderly patients and in patients who have comorbidities in office-based endoscopy (day-case anesthesia).

In this study, we compared the efficacy of topical palatable lidocaine gel as an adjuvant to propofol with the efficacy of i.v. propofol only for i.v. sedation, or for inducing anesthesia in upper GIT endoscopy, and its effect on propofol consumption.

 Patients and methods

Our target population comprised patients of both sexes older than 14 years with no allergies to lidocaine and undergoing day-case diagnostic upper GIT endoscopy for various indications at the Endoscopy Unit in Ain Shams University Hospital. Approval from the local ethics committee was obtained. The details regarding the study objectives and risks were fully explained to the patients, and those who agreed to participate in the study gave us written consent. The data collected from all enrolled patients before the procedure included age, sex, past medical history, past surgical history, medications, allergies, alcohol use, smoking, illicit drug use, and history of previous endoscopy (including tolerance to it). None of the participants had any severe pulmonary disease (asthma and chronic obstructive pulmonary disease).

We conducted a prospective double-blind study, and patients were computer randomized by closed envelope method into two groups: the palatable lidocaine gel group (X group) received 15 g of palatable lidocaine gel in addition to i.v. propofol mixed with 40 mg i.v. lidocaine. The control group (C group) received only i.v. propofol mixed with 40 mg i.v. lidocaine only.

All patients were monitored with pulse oximetry and for noninvasive arterial blood pressure. Heart rate, arterial blood pressure, and SaO 2 were recorded once before the start of i.v. sedation and every 5 min throughout the study period. A 20-G i.v. cannula was inserted in all patients.

In the X group, 15 g of palatable lidocaine gel was gradually applied 3-5 min before the procedure at three consecutive 30-s intervals to the base of the tongue, the peritonsillar areas, and the palate, and the patients were instructed to spread it inside their mouth using their tongue and then swallow it to cover the oropharynx and esophagus as well. Patients were asked to report the onset of numbness.

The endoscopist was totally blinded to the randomization. The endoscope used in the procedures was a GIF-1T 240 (11-mm diameter), Olympus CLV-U20, Pentax DVI-1, Pentax EPK-1000 (Olympus Optical, Tokyo, Japan).

In both study groups, nasal prongs were applied to the patient's nostrils and oxygen flow of 4 l/min was delivered. A mouthpiece was put in place, the patient was made to lie in the left lateral position, and a bolus dose of 50 mg i.v. propofol was administered at the start of the procedure, at increments of 10 mg as required. The endoscope was well lubricated before introduction. The occurrence of apnea during the procedure as well as the duration of the procedure was recorded. Finally, the total propofol dose was recorded at the end of the procedure.

After the procedure, patients were monitored in the recovery room. Time to recovery (time from the end of the procedure until the patient could stand upright) was recorded, and the participants were asked to report their dissatisfaction with and tolerance to the procedure on the basis of a Numerical rating scale ranging from 1 to 10 (1 = satisfied and the procedure is well-tolerated to 10 = unsatisfied). Patients were also asked about their willingness to undergo the procedure again using the same local anesthetic.

Finally, the endoscopist was asked to report the ease of performing the procedure and his or her satisfaction on the basis of on a Numerical rating scale ranging from 1 to 10 (1 = satisfied to 10 = not satisfied).

Statistical analyses

The required sample size was calculated using G*Power software (Heinrich Heine Universitδt, Dόsseldorf, Germany). It was estimated that a sample of 50 patients in either study group would achieve a power of 84% to detect an effect size (Cohen's d) of 0.6 as regards the difference in hemodynamic variables, propofol dosage, and dissatisfaction scores between the two study groups.

Statistical analysis was carried out using the statistical package for the social sciences (SPSS, version 17; SPSS Inc., Chicago, Illinois, USA). The Shapiro-Wilk test was used to examine the normality of numerical variables. Continuous numerical data were presented as mean and SD, and intergroup differences were compared with the independent-samples t-test. Discrete numerical data were presented as median and interquartile range and between-group differences were compared using the Mann-Whitney test. Qualitative data were presented as number and percentage, and the χ2 -test, or Fisher's exact test when appropriate, was applied for comparison of the two groups.

A P-value less than 0.05 was considered statistically significant.


Our study included 100 patients scheduled for diagnostic upper GIT endoscopy at the Endoscopy Unit in Ain Shams University hospitals. They included 53 male patients and 47 female patients with a mean age of 41.7 ± 13.9 years in the X group and 42.3 ± 13.3 years in the C group. There was no statistically significant difference between the two groups ([Table 1]).{Table 1}

Operative data

Heart rate and mean arterial blood pressure (MAP) at the start and end of the procedure showed no significant difference between the two groups, whereas oxygen saturation levels showed a significant drop in the C group (92.6 ± 3.2%) and significantly higher levels in the X group (99.4 ± 0.9%) ([Figure 1]).{Figure 1}

Propofol consumption was significantly lower in the X group (141.7 ± 53.5 mg) compared with the C group (238.6 ± 58.1 mg) ([Figure 2]). {Table 2}Recovery time was significantly shorter in the X group, which was 11.8 ± 4.8 min in contrast to 17.5 ± 3.9 min in the C group ([Figure 3]), whereas the procedure time was quite similar at 10.2 ± 4.3 and 8.8 ± 2.7 min in the X group and C group, respectively ([Table 2]).{Figure 3}{Table 2}

Incidence of apnea and gagging during the procedure was significantly lower in the X group. Apnea occurred only in six (12%) patients in the X group, whereas 68% of patients in the C group experienced apnea ([Figure 4] and [Table 3]). Moreover, only 14% of the patients who received palatable lidocaine gel suffered from gagging during the introduction of the endoscope, whereas 48% of the patients in the C group suffered gagging during the procedure ([Figure 5] and [Table 3]).{Table 3}{Figure 4}{Figure 5}

The satisfaction level of both endoscopists and patients was higher in the X group, whereas endoscopist dissatisfaction score was significantly higher in the C group compared with the X group (interquartile range 3-4 vs. 2-3, respectively). Similarly, patients' dissatisfaction score was significantly higher in the C group compared with the X group (interquartile range 5-7 vs. 3-4, respectively) ([Table 4] and [Figure 6]).{Table 4}{Figure 6}


Propofol (i.v.) is the most commonly used i.v. anesthetic that offers sedation and analgesia during upper GIT endoscopy [3]. However, i.v. anesthesia with propofol may cause potential harm to patients, especially to the elderly with comorbidities particularly when large doses are used. These side effects include hypotension, respiratory depression, and apnea [13].

Local oropharyngeal anesthesia using lidocaine spray, gel, or even lidocaine lollipop along with i.v. sedation has been studied in several trials, with the results showing that the use of lidocaine together with i.v. anesthetic increased patient comfort and tolerability to endoscope introduction and increased the endoscopist's satisfaction and ease of performing the procedure [14-18].

Although others have studied the effect of a posterior pharyngeal lidocaine gel [12], none of them had the advantage of applying a palatable one such as the palatable lidocaine gel used in our study, which increased patient satisfaction.

Our study noticed the hemodynamics during the procedure but there was no difference between the two groups; also, there was no difference as regards the duration of the procedure. These results did not agree with those of Osinaike and colleagues who found that changes in pulse rate were significant after sedation, during probe insertion, during scoping, at removal of the probe, and immediately after the procedure (P < 0.02). The mean change in systolic blood pressure was not significant throughout the procedure when compared with baseline; however, 14 (35%) patients developed transient hypertension [19].

The dose of propofol was markedly less in the palatable lidocaine gel group to the extent that one patient did not need the induction dose of propofol, and the procedure was performed totally with palatable lidocaine gel without any gagging or discomfort during the procedure. Similarly, many studies admitted that the application of posterior pharyngeal lidocaine in the form of gel or spray decreased the need for i.v. sedation [12].

These low doses of propofol in the palatable lidocaine gel group also reflected on the recovery time, which was significantly reduced in the palatable lidocaine gel group compared with the propofol-only group. This of course decreased hospital stay and costs.

We also studied SPO 2 levels during the procedure, and patients on palatable lidocaine gel showed better values compared with the control group showed lower values. This may be attributed to the greater incidence of apnea among patients in the control group, which in consequence may be due to the greater doses of i.v. propofol needed in the propofol-only group. Reinforcing our findings, Osinaike and colleagues and Sarwar et al. [20] noticed that mild to moderate hypoxia is common during endoscopic procedures and of no serious consequence. However, severe hypoxia was less common [19,21].

Our study also showed a decrease in the incidence of gagging in the palatable lidocaine gel group as the gag reflex is effectively inhibited on application of a thick layer of lidocaine to the posterior pharyngeal wall, which was reflected in the form of significant increase in patient satisfaction and tolerability to the procedure as well as increased endoscopist satisfaction. These results were consistent with the results of the study performed by Soweid et al. [12], which also concluded that posterior lingual lidocaine swab improved patient comfort and tolerance and endoscopist satisfaction.

Although we did not compare the costs incurred between the palatable lidocaine gel group and the propofol-only group, the use of the palatable lidocaine gel seems to involve lower cost as the reduced propofol consumption, reduced complications related to large doses of i.v. propofol used, reduced recovery time, and decreased hospital stay all contribute to reducing expenses. Moreover, increased ability to work and drive immediately after the procedure appears to decrease the overall costs.

One of the limitations of this study is that we did not consider the level of anxiety and patient age, and their contribution to the tolerability to the procedure. However, this issue was researched by other studies such as those by Soma et al. [18] and Mulcahy et al. [15], which showed that a high level of anxiety, young age, and a strong gag reflex are risk factors for poor tolerance to upper GIT endoscopy. In contrast, Pereira et al. [22] showed that patient anxiety did not contribute to procedure tolerance.

In conclusion, this study showed that the use of palatable lidocaine gel can reduce the dose of i.v. propofol along with its potential complications and can even be used as a sole anesthetic agent in upper GIT endoscopy, sparing the use of i.v. sedation. In addition, this may help patients resume their daily activities immediately after the procedure, decreasing the overall cost of the procedure. This may be a very promising modality especially in elderly patients who have comorbidities, and in office-based upper GIT endoscopy. However, larger, multicenter studies should be conducted to confirm and validate the results of our study.



1American Society for Gastrointestinal Endoscopy. Anesthetic lollipop can prepare patients for upper GI endoscopy; Science Daily; 17 October 2007. Available at: [Accessed 2014 Mar 12]
2 Clarke GA, Jacobson BC, Hammett RJ, Carr-Locke DL. The indications, utilization and safety of gastrointestinal endoscopy in an extremely elderly patient cohort. Endoscopy 2001; 33:580-584.
3 Waring JP, Baron TH, Hirota WK, Goldstein JL, Jacobson BC, Leighton JA, et al. Guidelines for conscious sedation and monitoring during gastrointestinal endoscopy. Gastrointest Endosc 2003; 58:317-322.
4 Külling D, Rothenbühler R, Inauen W. Safety of nonanesthetist sedation with propofol for outpatient colonoscopy and esophagogastroduodenoscopy. Endoscopy 2003; 35:679-682.
5 Bell GD. Premedication, preparation, and surveillance. Endoscopy 2002; 34:2-12.
6 Clarke AC, Chiragakis L, Hillman LC, Kaye GL. Sedation for endoscopy: the safe use of propofol by general practitioner seditionists. Med J Aust 2002; 176:158-161.
7 Bassi GS, Humphris GM, Longman LP. The etiology and management of gagging: a review of the literature. J Prosthet Dent 2004; 91:459-467.
8 Miller AJ. Oral and pharyngeal reflexes in the mammalian nervous system: their diverse range in complexity and the pivotal role of the tongue. Crit Rev Oral Biol Med 2002; 13:409-425.
9 AstraZeneca LP. Xylocaine (lidocaine hydrochloride) jelly. Available at: [Accessed 2014 Jan 6]
10Stolz D, Chhajed PN, Leuppi J, Pflimlin E, Tamm M. Nebulized lidocaine for flexible bronchoscopy: a randomized, double-blind, placebo-controlled trial. Chest 2005; 128:1756-1760.
11Tang WL, Liu SJ, Jiang XW. Associated sedation of propofol and midazolam in small dosage and gastroscopy. Hunan Yi Ke Da Xue Xue Bao 2001; 26:463-465.
12Soweid AM, Yaghi SR, Jamali FR, Kobeissy AA, Mallat ME, Hussein R, et al. Posterior lingual lidocaine: a novel method to improve tolerance in upper gastrointestinal endoscopy. World J Gastroenterol 2011; 17:5191-5196.
13Seinelä L, Reinikainen P, Ahvenainen J. Effect of upper gastrointestinal endoscopy on cardiopulmonary changes in very old patients. Arch Gerontol Geriatr 2003; 37:25-32.
14Mulcahy HE, Greaves RR, Ballinger A, Patchett SE, Riches A, Fairclough PD, et al. A double-blind randomized trial of low-dose versus high-dose topical anaesthesia in unsedated upper gastrointestinal endoscopy. Aliment Pharmacol Ther 1996; 10:975-979.
15Mulcahy HE, Kelly P, Banks MR, Connor P, Patchet SE, Farthing MJ, et al. Factors associated with tolerance to, and discomfort with, unsedated diagnostic gastroscopy. Scand J Gastroenterol 2001; 36:1352-1357.
16Leitch DG, Wicks J, el Beshir OA, Ali SA, Chaudhury BK. Topical anesthesia with 50 mg of lidocaine spray facilitates upper gastrointestinal endoscopy, Gastrointest Endosc 1993; 39:384-387.
17Ayoub C, Skoury A, Abdul-Baki H, Nasr V, Soweid A. Lidocaine lollipop as single-agent anesthesia in upper GI endoscopy. Gastrointest Endosc 2007; 66:786-793.
18Soma Y, Saito H, Kishibe T, Takahashi T, Tanaka H, Munakata A. Evaluation of topical pharyngeal anesthesia for upper endoscopy including factors associated with patient tolerance, Gastrointest Endosc 2001; 53:14-18.
19Campo R, Brullet E, Montserrat A, Calvet X, Rivero E, Brotons C. Topical pharyngeal anesthesia improves tolerance of upper gastrointestinal endoscopy: a randomized double-blind study. Endoscopy 1995; 27:659-664.
20Sarwar S, Alam A, Khan AA. Pulse oximetry during gastrointestinal endoscopic procedures. J Coll Physicians Surg Pak 2006; 16:97-100.
21Osinaike BB, Akere A, Olajumoke TO, Oyebamiji EO. Cardiorespiratory changes during upper gastrointestinal endoscopy, Afr Health Sci 2007; 7:115-119.
22Pereira S, Hussaini SH, Hanson PJ, Wilkinson ML, Sladen GE. Endoscopy: throat spray or sedation? J R Coll Physicians Lond 1994; 28:411-414.