Healthcare and Medicine Reference
The midline or the paramedian approach can be used (Figure 7.5).
The midline approach is easier to learn and is successful in the
majority of cases. The paramedian approach can be useful in diffi -
cult cases where bony osteophytes, calcifi ed ligaments or narrowed
intervertebral spaces obstruct a midline approach.
Step-by-step guide: lumbar puncture
Obtain informed consent.
Prepare equipment (see Box 7.3 and Figure 7.6).
Position the patient (see 'Patient positioning' above).
Scrub up - wear mask, hat, sterile gown and gloves. You will see
the procedure performed with sterile gloves only but this is bad
practice. An epidural abscess can leave a patient paralysed!
Sterilise the skin of the patient's lower back with a spirit-based
antiseptic (2% chlorhexidine or betadine) (Figure 7.7a) and pre-
pare a sterile fi eld with drapes covering the anterior superior iliac
spines so that Tuffi er's line (L3-L4 level) can be identifi ed with-
out desterilising oneself (Figure 7.7b).
Figure 7.3 Sitting position.
Box 7.3 Equipment for lumbar puncture
Sterile gown and gloves, mask and hat
Sterile pack - with gauze, galley pot
Chlorhexidine/betadine in spirit
25G needle (orange)
Collection tubes: three sterile universal containers + glucose tube
(fl uoride/grey top)
Figure 7.4 Lateral position.
Figure 7.5 Midline and paramedian approaches to lumbar puncture.
Figure 7.6 Equipment for lumbar puncture.