Effectiveness of 10% Lidocaine Spray on Relieving Local Pain Caused by Intravenous (IV) Intubation: a Randomized Control Trial
Phase: PHASE3
Conditions: Pregnancy
Sponsor: Phenikaa University

 
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Effectiveness of 10% Lidocaine spray on relieving local pain caused by 
intravenous (IV)  intubation among women before Cesarean section: a double-
blind randomized control trial 
Anh Thi Ngoc Pham1, Hanh Thi Phung2,3, Khanh Thi Nguyen4 , Hung Trong Mai5, , Ha Thi My Truong 5 , Quang The Tran 6 
Huong Thi Xuan Hoang1 
1 Faculty of Nursing, Phenikaa University 
2 Hanoi Medical University 
3 Vietduc University Hospital 
4 The Chinese University of Hong Kong 
5  Hanoi Obstetrics and Gynecology Hospital 
6 Thanh Nhan Hospital 
 
  
Corresponding author 
Huong Thi Xuan Hoang (Ph.D) 
Faculty of Nursing, Phenikaa University 
huong.hoangthixuan@phenikaa-uni.edu.vn 
 
 

 
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Abstract 
Background: Current evidence of the effectiveness of Lidocaine spay on relieving local 
pain caused by intravenous intubation among women before Cesarean section, while 
promising, is unknown. The objective of this study was to explore the effect of 
Lidocaine spray on relieving local pain caused by intravenous intubation among such 
participants. 
Methods: Participants were assigned randomly into Group 1 (intervention group) or 
Group 2 (control group). Participants in group 1 received 3 sprays of 10% Lidocaine 
before the intravenous intubation while participants in group 2 received 3 spays of 
sterile water. A 100mm Visual Analogue Scale (VAS) was used to record the pain 
intensity directly after intravenous cannulation by the subjects. The adverse events and 
success rate of IV cannulation were also reported. 
Results: The results indicated that the spray  10% Lidocaine had clinical significance in 
reducing the pain caused by intravenous intubation among women before Cesarean 
section. The VAS score in the intervention group was statistically lower than in the 
control group (p<0.01)  
Conclusion: The results of the study suggest the effectiveness of 10% Lidocaine spray 
in managing intravenous intubation-related pain. It is recommended to perform further 
studies to compare the Lidocaine effect with other anesthetic options to determine the 
better technique for reducing pain associated with intravenous cannulation. A further 
trial to test the placebo effect of sterile water is also recommended. 
Trial registration: Phenikaa University under register 42/QĐ-ĐHP-SĐH on January 
13th, 2023 
Keyword: pain, Lidocaine, VAS, women, C-session, intravenous. 
 
 
 

 
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Introduction 
Intravenous (IV) cannulation is a technique in which a cannula is placed inside a vein 
through the patient’s skin. It is the most commonly performed procedure in clinical 
settings. Nevertheless, it is also the second most painful procedure that significantly 
elevates a patient's anxiety levels (1, 2). IV cannulation is required for every patient 
before their operation. Managing this pre-operative pain has been listed as an indicator 
of the quality of anesthesia (3). As such, various interventions have been conducted to 
reduce the pain caused by intravenous intubation among patients. Non-pharmacological 
approaches to reduce this pain include using the flash of light to distract patients, cough 
tricks, Valsalva manoeuvers, and vapor coolant spray, essential oil (4-8). 
Pharmacological approaches for reducing local pain caused by IV include Lidocaine 
cream/patch/spray, EMLA (mixture of Lidocaine and Prilocain), diclofenac 
transdermal, and Piroxicam gel (9-12). However, none of these methods exhibited a 
clear superiority over the others. There is no clear consensus about which method is the 
best option to relieve pain induced by IV (10). Among pharmacological approaches, 
using Lidocaine provides some promising results in reducing pain related to IV 
insertion. Among the different dosage forms, Lidocaine spray is the most convenient 
with a fast effect. It is quickly absorption within 1 to 5 minutes (13).  However, 
inconsistent results have been reported regarding this application (9, 10, 13-16). 
Notably, previous trials conducted in different populations, ages, settings, and needle 
sizes somewhat cause bias in the results. As such, more trials with rigorous design 
should be implemented to provide strong evidence to support the role of Lidocaine spray 
in reducing local paint caused by IV intubation. The objective of this study was to 
evaluate the effect of Lidocaine spray on relieving local pain caused by intravenous 
intubation. To ensure a homogeneous population, we chose the participants who were 
women before their Cesarean section delivery (C-section). 
Methods 
A randomized double-blind placebo-controlled trial design was performed at hospitals 
in Hanoi Obstetrics and Gynecology Hospital, Vietnam, from 12/2023 to 01/2024.  
Inclusion criteria 

 
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Inclusion criteria comprised participants who were going to undergo a scheduled C-
section delivery; were over 18 years old; able to read and write Vietnamese. 
Exclusion criteria 
Participants who were emergency cases for going to a C-section delivery  
Sample size calculation 
The sample size was determined using the equation for comparing two means with an 
alpha of 0.05, a power of 0.80, and an SD from the previous study to have a minimum 
sample of 50. As such we decided to recruit 150 participants (50 per group) to ensure 
the power of analysis. 
Randomization, allocation, and blinding 
This was a double-blinded study. The interventionist and the participants were blinded 
to whether the participants were receiving 10% Lidocaine spay or sterile water spray. 
Only the researcher who applied the spray was aware of the content. To ensure the 
success of blinding, the sterile water was contained in a bottle exactly like the 10% 
Lidocation spray. The nurses and participants were required to wear masks during the 
procedure. Block randomization was applied to keep an equal size for each trial arm. 
Eligible participants were randomized into two study groups in a 1:1 ratio, in blocks of 
four. 
Trial arms: 
There were one group receiving the intervention (group 1) and two control groups 
Participants in group 1 were given three sprays of 10% Lidocaine (Lidocaine 10% pump 
spray, Egis) 3 minutes before the interventionist performed the insertion of a catheter 
into their vein while the control group received 3 sprays of sterile water. Participants in 
usual care group receive standard IV placement procedures. 
Study Procedures 
The main researcher approached potential participants a day before their C-section and 
invited them to participate. After signing the consent form, participants were randomly 

 
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assigned to one of the two study groups. Before their C-section, the main researcher 
gave participants in group 1 three sprays of Lidocaion 10% (Lidocaine 10% pump 
spray, Egis) 3 minutes before the interventionist performed the insertion of a catheter 
into their vein while the control group received 3 sprays of sterile water. Each dose of 
the spray consisted of 0.1 ml liquid (4.8 mg Lidocaine/spray) and had the same colour 
and appearance as sterile water. The researcher sterilised the intended injection sites (2 
sides) with alcohol swabs and applied Lidocaine spray/sterile water as the application 
aligns with the hospital’s policy. After 3 minutes, the main researcher wiped the 
remained Lidocaine/sterile water and then marked the area. After that, the 
interventionist performed the IV cannulation using a 18 G IV cannula (Vasofix safety, 
BBraun). All IV cannulations were performed by two interventionists from Operation 
Room of the hospital. Before cannulation, the main researchers recorded any reaction 
on the skin. After successful cannulation, as confirmed by visible blood in the infusion 
needle, the needle was removed immediately. The participants recorded their pain 
perception directly after the procedure on a VAS, consisting of a nongraduated 100mm 
horizontal line ranging from ‘0 = did not hurt at all’ to ‘100 = as painful as it could be’.  
Measurements 
The primary outcome was pain intensity directly after IV cannulation reported by the 
subjects using a 100mm Visual Analogue Scale (VAS). The secondary outcomes were 
adverse events, the success rate of IV cannulation. 
Data analysis 
Data were cleaned and analyzed by The Statistical Package for the Social Sciences v.20. 
The intention-to-treat (ITT) principle was adopted for analyzing the data. Between-
group differences were examined using the T-Test or χ2 test with p < 0.05 indicating a 
statistically significant different.