Efficacy of topical anesthesia in children
R. J. Vinci and S. S. Fish
Department of Pediatrics, City Hospital, Boston, Mass, USA.
OBJECTIVES: To compare the efficacy of three formulations of a topical
anesthetic solution composed of various concentrations of tetracaine
hydrochloride, adrenaline (epinephrine), and cocaine hydrochloride (TAC),
and to compare the cost of the topical anesthetic solutions with the cost
of lidocaine infiltration. DESIGN: Randomized, double-blind clinical trial.
SETTING: Urban pediatric emergency department. PARTICIPANTS: One hundred
fifty-six children 3 to 18 years of age and older requiring topical
anesthesia for suturing of lacerations. INTERVENTION: Children received 3
mL of one of the following study solutions: TAC 1 consisting of 0.5%
tetracaine, 1:2000 dilution of adrenaline, 11.8% cocaine; TAC 2 that
contained 1% tetracaine, 1:2000 dilution of adrenaline, 4% cocaine; or TAC
3 made up of 1% tetracaine and 4% cocaine, without adrenaline. MEASUREMENTS
OR MAIN RESULTS: Patients were randomized to group 1 (n = 49), group 2 (n =
49), or group 3 (n = 58), and received TAC 1, TAC 2, or TAC 3,
respectively. Patients in the three study groups were similar for age,
gender, anatomic location and length of the laceration, and history of
sutures or use of topical anesthesia. Based on the physician assessment of
achievement of complete, partial, or no anesthesia, solutions containing
11.8% cocaine (TAC 1) and 4% cocaine with adrenaline (TAC 2) were more
likely to produce complete anesthesia than the solution with 4% cocaine
without adrenaline (TAC 3) (P < .001, chi 2). This difference was only
noted when the laceration involved the face or scalp. A second dose of the
TAC 3 solution was more often required to produce anesthesia when compared
with the other two study drugs (P < .003, chi 2). The final cost to
produce 3 mL of the study drugs, including the vials, was $16.39 for TAC 1,
$8.67 for TAC 2, and $8.41 for TAC 3. CONCLUSIONS: The application of a TAC
solution containing 4% cocaine is as effective as a TAC solution containing
11.8% cocaine. Use of the 4% solution decreases the cost of the agent.
Adrenaline is a necessary ingredient in the anesthetic solution.
