Lumbar puncture: lidocaine had no clear effect on traumatic taps.

Clinical bottom line (level 1b-)

  1. Children who require a lumbar puncture and were given lidocaine had no clear difference in having a successful first attempt in obtaining cerebrospinal fluid, than those given no local anaesthetic.
  2. There was no clear difference in traumatic lumbar puncture (considered as more than 10,000x10 6 /L red blood cells) in the cerebrospinal fluid.
  3. Children who were given lidocaine were more likely to have a traumatic lumbar puncture (considered as more than 1000x10 6 /L red blood cells) in the cerebrospinal fluid (NNH = 7 at unknown) .
Carraccio et al: Archives of Pediatric and Adolescent Medicine 1996; 150: 1044-1046
Expires January 2003

The study

?blinded ?concealed randomised trial with intention-to-treat
Setting: paediatric emergency department of a university hospital, USA

100 patients (aged range 0.3 to 35 months; mean 5 months, ?% male) needed to undergo a lumbar puncture as part of their diagnostic workup
Control Group: (n = 49, 49 analysed): no local anaesthetic given
Experimental Group: (n = 51, 51 analysed): lidocaine injected subcutaneously using a standard dose and procedure

100% followed for ?
Outcome notes:
  • traumatic lumbar punctures at first attempt (low red blood cells positive) : using more than 1000X10 6/L red blood cells in the cerebrospinal fluid as traumatic
  • traumatic lumbar punctures at first attempt (high red blood cells positive) : using more than 10, 000X106 /L red blood cells in the cerebrospinal fluid as traumatic

The evidence

Outcome Time to outcome CEREERRRR
(95% CI)		ARR
(95% CI)		NNT
(95% CI)
success in obtaining cerebrospinal fluid at first attempt unknown 29
(59.2%)		 30
(58.8%)		 1.00%
(-38.0% to 28.0%)		 0.36%
(-18.9% to 19.6%)		 280
(NNT = 5 to infinity;
NNH = 5 to infinity)
traumatic lumbar punctures at first attempt (low red blood cells positive) unknown 3
(6.12%)		 10
(19.6%)		 -220%
(-995% to 6.00%)		 -13.5%
(-26.3% to -0.69%)		 -7
(-150 to -4)
traumatic lumbar punctures at first attempt (high red blood cells positive) unknown 2
(4.08%)		 2
(3.92%)		 4.00%
(-556% to 86%)		 0.16%
(-7.53% to 7.85%)		 630
(NNT = 13 to infinity;
NNH = 13 to infinity)

Comments

  1. No comment on patient pain made!
  2. Depending on the definition, lidocaine may increase the risk of traumatic lumbar puncture.
  3. For the physicians in training the advice is: When doing LP's, go for local anaesthesia! The more you do it, the better you will be at it!

Citation

  1. Carraccio C, Feinberg P, Sinclair L, et al: Lidocaine for lumbar puncture: A help not a hindrance. Archives of Pediatric and Adolescent Medicine 1996; 150: 1044-1046
Contributor: Clare Wotton and Bob Phillips, January 2000
Reviewer: Mona Nabulsi

Clinical Question.
Patient requiring lumbar puncture
Intervention or Exposure lidocaine
Comparison no lidocaine
Outcome collection of CSF