Lumbar Puncture: Remember to Measure Opening Pressure
The usual reason for not measuring opening pressure at lumbar puncture is forgetting to include a manometer (pressure guage) in your equipment.
At LP, opening pressure should be measured without exception in the investigation of acute headache. Always remember to measure opening pressure with your patient lying on their […]
Lumbar Puncture fact #4
Manometry is the measurement of CSF pressure using a 40cm long plastic gauge. The most common error is not to attemmpt to measure pressure! Measuring pressure is essential in patients presenting with acute headache, as a high or low opeinng pressure may be the only indication that there is a […]
Lumbar Puncture Fact #3
22 guage atraumatic needles are now recommended for diagnostic Lumbar Puncture (LP). An atraumatic needle has a rounded tip and is said to avoid cutting the fibres of the dura. If the fibres of the dura are separated without cutting, and the resulting hole is less likely to persist, […]
Lumbar Puncture Fact #2
The distance from skin to the ligamentum flavum (the tough ligament just befire you reach the epidural space) is between 4 and 7cm in adults. Does anyone know an up-to-date study of this (i.e. if we are getting more obese, is this still true today?)
A calm environment
A trained nurse to assist
Careful explanation to patient of what to expect
Spend time on positioning the patient properly
Make sure you achieve cutaneous anaesthesia
Remember the 6 layers from skin to CSF
Loosen manometer tap and connect to manometer guage before you insert needle
Collect adequate specimens (2mls per bottle - 8mls is only 1.6% of total […]
The perfectionists will argue that an LP should always be attempted with your patient lying on their side. There are some situations where this is unavoidable - a comatose patient, someone in whom opening pressure needs measured. However, an LP is easier to perform with the patient seated - it is much easier to appreciate […]
There are 6 layers your needle must pass through from skin to CSF.
1. Dermis
2. Subcutaneous fat (most variable distance - more fat, further to go)
3. Interspinous ligament
4. Ligamentum flavum
5. Epidural space
6. Meninges