The skin-epidural distance was measured in 274 children to assess the
usefulness of 1 mm.kg(-1) as a guideline. Children aged between I 2 da
ys and 16 years, weighing between 2 and 43 kg were investigated. Lumba
r epidurals were performed under general anaesthesia using a midline a
pproach in the L(3.4) interspace with the patient in the left lateral
position. Good correlation between skin-epidural distance and age and
weight was demonstrated. No statistical difference was shown when plot
ting the best fit regression line. skin-epidural distance (mm) = 0.8 w
eight (kg) + 3.93 (R(2) = 0.74) and its 95% confidence limits and skin
-epidural distance (mm) = weight (kg) for children between 6 months an
d 10 years. Poor correlation was noted below 6 months (n = 22) and ove
r 10 years (n = 19). No dural puncture or bloody tap occurred. One mm.
kg(-1) body weight was shown to be a useful guideline for children bet
ween 6 months and 10 years of age.