Easing the pain: lignocaine spray in mid-trimester amniocentesis – A randomized double-blind, placebo-controlled trial

Abstract

Background: To evaluate the effect of lignocaine spray on maternal pain perception during mid
trimester amniocentesis compared to placebo.
Methodology: This was a double-blinded, prospective, randomized controlled trial conducted at a tertiary
teaching hospital in Western Rajasthan. Singleton pregnancies between 15- and 24-weeks’ gestation
undergoing amniocentesis were included. Participants were randomly assigned to receive either
lignocaine spray or placebo (normal saline). Pain was assessed using the Visual Analogue Scale (VAS),
Verbal Rating Scale (VRS), and Numerical Rating Scale (NRS). A total of 138 women were enrolled,
with 69 receiving lignocaine spray and 69 receiving placebos.
Results: Pain perception measured by VAS showed no significant difference between the lignocaine and
placebo groups (p = 0.412). VRS and VAS demonstrated a positive correlation (r = 0.692, p < 0.001).
Median VAS scores at 30 minutes post-procedure were significantly lower in the lignocaine group (p =
0.008). The Kappa agreement between VAS and VRS was found to be 59.20%. No significant difference
in procedure-related complications was observed between groups.
Conclusion: The study demonstrates no significant difference in VAS scores or secondary outcomes
between the lignocaine and placebo groups, suggesting that lignocaine spray may not provide additional
benefit for pain relief in amniocentesis.