How to succeed on your next Lumbar Puncture

You are in the ED and have just finished draining that notorious ‘spider bite/abscess’ when a fussy 17 day old infant comes through triage with a fever to 38.9 C. We all know what is coming… SBI work up including lumbar puncture time… but the last thing a resident or any provider wants to do is be unsuccessful with tap leading to prolonged hospitalizations and antibiotic exposure. Here we will discuss not only how to better one’s chances of success but why.

In 2006 Baxter et al. published their findings of a prospective observational study in PEDIATRICS. They reviewed 428 of 594 LPs performed, 377 of which were done by trainees. Seventy-four percent (279/377) of the trainee LPs were successful. Amongst other factors local anesthesia was used for 280 (74%), and 225 (60%) were performed with early stylet removal. They found the following;

• LPs were more likely to be successful in infants >12 weeks of age – OR=3.1 (95% CI 1.2-8.5)
• Local anesthetic use showed increased odds of success OR=2.2 (95% CI 1.04-4.6)
• In infants ≤12 weeks of age, early stylet removal improved success rates – OR=2.4 (95% CI 1.1-5.2)
• Position (upright vs side-lying), drape use, and year of training were not significant predictors of success

Of note, of the anesthesia users in this study, only 4% used injected lidocaine and the rest used EMLA LMX.

In 2007 Nigrovic et al., in their prospective cohort of 1,474 lumbar punctures, looked at risk factors for traumatic or unsuccessful lumbar punctures in the first attempt.  Of the 1,474 lumbar punctures, 513 (35%) were traumatic or unsuccessful after the first attempt due to 1. Lack of physician experience (OR 1.08; 95% confidence interval

[CI] 1.01 to 1.15), lack of local anesthetic use (adjusted odds ratio 1.6; 95% CI 1.1 to 2.2), advancement of the spinal needle with stylet in place versus stylet removed (adjusted odds ratio 1.3; 95% CI 1.04 to 1.7), and increased patient movement (adjusted odds ratio 2.1; 95% CI 1.6 to 2.6). They also found that age of <3 months increased likelihood of being unsuccessful.

Interestingly:

• The presence of a family member(s) was not associated with an increased risk of traumatic or unobtainable lumbar puncture, nor was it associated with more attempts at the procedure as seen in a study also by Nigrovic et al (3).
• The viewing of an educational video prior to performing an Lumbar Puncture by a study Srivastava et al. in 2012 showed that viewing the video helps with provider comfort in performing the procedure, but it does not help in actually being successful (4).

Boiled down, here are the results

What improves success

• Experienced holder –Can’t be stressed enough! If you can’t keep patients safely in proper position, consider procedural sedation
• Age > 12 weeks – spinal canal larger, dural pop more pronounced
• Anesthesia use (topical and injectable) – the better pain is controlled = less wiggle
• Oral Sucrose – safe, easy to administer but insufficient alone
• Early stylet removal – able to appreciate CSF flash when in spinal canal

What does not improve success:

• Position (upright vs side lying)
• Drape use
• Conflicting between the studies: Year of training.  Although significant but with only a slight increase in OR in Nigrovic et al. study (2), no difference in the Baxter et al.
• Video Viewing of Procedure

Keep these tips handy as you perform your next lumbar puncture. Happy CSF collecting!

References

1. Baxter AL, Fisher RG, Burke BL, et al. Local anesthetic and stylet styles: factors associated with resident lumbar puncture success. Pediatrics 2006; 117:876.
2. Nigrovic LE, Kuppermann N, Neuman MI. Risk factors for traumatic or unsuccessful lumbar punctures in children. Ann Emerg Med 2007; 49:762.
3. Nigrovic, L. E., A. A. Mcqueen, and M. I. Neuman. “Lumbar Puncture Success Rate Is Not Influenced by Family-Member Presence.” Pediatrics 120.4 (2007): n. pag. Web.
4. Srivastava, Geetanjali, Mark Roddy, Daniel Langsam, and Dewesh Agrawal. “An Educational Video Improves Technique in Performance of Pediatric Lumbar Punctures.” Pediatric Emergency Care 28.1 (2012): 12-16. Web.