Pediatric lumbar punctures can have much higher success rates when proper positioning and technique are emphasized. The position should be the lateral decubitus position with hips flexed, but the neck does not need to be flexed. The spinal cord ends at L3 in newborns so the lumbar puncture should be performed at the top of the iliac crest.
Cerebral spinal fluid lactate level greater than or equal to 3.5 mmol/L or greater than or equal to 63 mg/dL in children suggests bacterial meningitis. Febrile infants less than three months old with a urinary tract infection have 2% concomitant meningitis.
Contraindications to lumbar punctures in children are as follows:
- Cushing’s triad: hypertension, bradycardia, and irregular breathing
- Unequal pupils
- Cranial nerve palsy
- Decorticate or decerebrate posturing
- Abnormal Doll’s Eyes Reflex
- Status epilepticus
Schulga P, et al. How to use…lumbar puncture in children. Arch Dis Child Educ Pract Ed 2015; 100: 264–271.