A randomised, double-blind, placebo-controlled, comparative study of topical skin analgesics and the anxiety and discomfort associated with venous cannulation.
OBJECTIVE
To compare the effect of topical skin anaesthetic agents on the discomfort and anxiety associated with venous cannulation.


METHODS
Randomised, double-blind, placebo-controlled, within subject, volunteer trial.


METHODS
20 healthy volunteers underwent venous cannulation on three separate occasions having received topical skin application of either 4% amethocaine gel (Ametop), 5% eutectic mixture of lidocaine and prilocaine (EMLA) or E45 cream (placebo). Visual analogue and verbal rating scales were used to assess pain and anxiety associated with the venous cannulation, and anticipated anxiety for future cannulation, under each drug condition.


RESULTS
Subjects were aged 22-53 years (mean 32.8 years). The mean visual analogue scores (VAS) for discomfort were found to be significantly lower (p< 0.001) with Ametop (VAS = 18mm) and EMLA (VAS = 29mm) compared with the control (VAS = 38mm). There was a positive correlation (R2 = 72%, p<0.001) between discomfort and the predicted anxiety if cannulation was to be repeated with the same cream. With the placebo a positive correlation (R2 = 19.8%, p = 0.05) was found between the level of anxiety before cannulation and the level of discomfort recorded.


CONCLUSIONS
Ametop and EMLA topical anaesthetic agents produce effective skin analgesia for venous cannulation. The use of topical analgesia can reduce perceived anxiety about future cannulation procedures. This has application in the management of anxious patients undergoing intravenous sedation, suggesting that topical analgesia prior to venous cannulation may significantly aid anxiolysis.
Speirs
A F
AF
Division of Restorative Dentistry, Leeds Dental Institute, University of Leeds, UK.
Taylor
K H
KH
Joanes
D N
DN
Girdler
N M
NM
D000279:Administration, Cutaneous; D000328:Adult; D000704:Analysis of Variance; D000766:Anesthesia, Dental / Q000295:instrumentation*; D019162:Anesthetics, Combined / Q000008:administration & dosage*; D000779:Anesthetics, Local / Q000008:administration & dosage*; D001794:Blood Pressure; D002406:Catheterization, Peripheral / Q000009:adverse effects / Q000295:instrumentation*; D016292:Procedural Sedation / Q000295:instrumentation; D016854:Dental Anxiety / Q000209:etiology / Q000517:prevention & control*; D004311:Double-Blind Method; D005260:Female; D006339:Heart Rate; D006801:Humans; D008012:Lidocaine / Q000008:administration & dosage*; D000077442:Lidocaine, Prilocaine Drug Combination; D016014:Linear Models; D008297:Male; D008347:Manifest Anxiety Scale; D008875:Middle Aged; D010146:Pain / Q000209:etiology / Q000517:prevention & control*; D010147:Pain Measurement; D011318:Prilocaine / Q000008:administration & dosage*; D013748:Tetracaine / Q000008:administration & dosage*; D014680:Veins
D019162:Anesthetics, Combined; D000779:Anesthetics, Local; D000077442:Lidocaine, Prilocaine Drug Combination; D011318:Prilocaine; D013748:Tetracaine; D008012:Lidocaine