CONTRAINDICATIONS : Increased intracranial pressure Cerebral herniation Impending herniation Possible increased ICP and focal neuro signs Coagulopathy Prior lumbar surgery Severe vertebral osteoarthritis or degenerative disc disease Significant cardiorespiratory compromise Infection near the puncture site Space occupying lesion
EQUIPMENT : Spinal needle Less than 1 yr: 1.5in 1yr to middle childhood: 2.5in Older children and adults: 3.5in Three-way stopcock Manometer 4 specimen tubes Local anesthesia Drapes Betadine
PROCEDURE : Performed with the patient in the lateral recumbent position. A line connecting the posterior superior iliac crest will intersect the midline at approx. the L4 spinous process. Spinal needles entering the subarachnoid space at this point are well below the termination of the spinal cord.
LP in older children may be performed from L2 to L3 interspace to the L5 to S1 interspace. At birth, the cord ends at the level of L3. LP in infant may be performed at the L4 to L5 or L5 to S1 interspace.
Position the patient: Generally performed in the lateral decubitus position. A pillow is placed under the head to keep it in the same plane as the spine. Shoulders and hips are positioned. perpendicular with the table. Lower back should be arched toward practitioner.
a. Ligament flavum is a strong, elastic, yellow membrane covering the interlaminar space between the vertebrae.b. Interspinal ligaments join the inferior and superior borders of adjacent spinous processes.c. Supraspinal ligament connects the spinous processes
A topical anesthetic (e.g. EMLA cream) can be applied 30 to 60 minutes before performing the puncture to minimize pain on penetration. Either a sitting or lateral decubitus position can be used . Monitor the patient visually and with pulse oximetry for any signs of respiratory difficulty as a result of assumed position. The subarachnoid space must be entered below the level of spinal cord termination. The spine should be flexed maximally to increase spacing between spinous processes. Extensive neck flexion, however, should be avoided to minimize a chance of respiratory compromise. Make sure the hips and shoulders are aligned & are perpendicular to the bed surface.
The patient’s back should be carefully prepared and draped using provided disinfecting solution and drapes. Orient yourself anatomically and find the L4 spinous process at the level of iliac crests Palpate a suitable interspace distal to this level. Infiltrate 2% Lidocaine subcutaneously (without epinephrine to prevent cord infarction should it be introduced into the cord by accident) with a fine needle. A field block can be applied injecting into and on either side of the interspinous ligaments. Identify the two spinal processes in between which the needle will be introduced, penetrate the skin and slowly advance the tip of the needle at about 10 degrees cephalad (i.e. toward the patient’s umbilicus).
Remove the stylet and check for clear fluid will flow from the needle when the subarachnoid space has been penetrated. The ligaments offer resistance to the needle, and a “pop” is often felt as they are penetrated. Withdraw the needle leaving the tip in, recheck the landmarks and slowly progress the needle again. Measure the opening pressure using the manometer by attaching it via a stopcock to the spinal needle. Normal opening pressure ranges from 10 to 100 mm H2O in young children and 60 to 200 mm H2O after eight years of age
CSF volume of 1cc obtained in 3 tubes. In the neonate, 2ml in total can be safely removed. In an older child 3 to 6 ml can be sampled depending on the child’s size. Tube 1 is used for determining protein and glucose Tube 2 is used for microbiologic and cytologic studies Tube 3 is for cell counts and serologic tests for syphilis
INDICATIONS : Diagnostic : - Idiopathic Thrombocytopenic Purpura - Aplastic Anemia - Leukemia - Megaloblastic Anemia - Infections e.g. Kala Azar - Storage disorders e.g. Gaucher’s disease - PUO - Myelofibrosis Therapeutic : - Bone Marrow Transplantation
CONTRAINDICATIONS : Hemorrhagic disorders such as congenital coagulation factor deficiencies (eg, hemophilia), disseminated intravascular coagulation and concomitant use of anticoagulants. Skin infection or recent radiation therapy at the sampling site. Bone disorders such as osteomyelitis or osteogenesis imperfecta.
PROCEDURE : Obtain consent from a parent or guardian. If the posterior iliac crest is the chosen site, patients are generally placed in the lateral decubitus position or the prone position Sterilize the site with the sterile solution Place a sterile drape over the site, and administer local anesthesia, letting it infiltrate the skin, soft tissues, and periosteum. After local anesthesia has taken effect, make an incision through which the bone marrow aspiration needle can be introduced .
If a guard is present, should be removed before starting bone marrow aspiration, to ensure adequate depth of penetration.. In general, the needle should be advanced at an angle completely perpendicular to the bony prominence of the iliac crest. Once the needle passes through the cortex and enters the marrow cavity, it should stay in place without being held. Once the periosteum has been penetrated, pressure is used to advance the needle through the cortex and rotate the needle in a semicircular motion, alternating clockwise and counterclockwise movements.
If the patient is in the lateral position, the hip may be stabilized with the other hand to get a better feel for the position and depth of the needle. The thumb of this hand can be to mark the desired site and to prevent accidental repositioning of the needle. A slight give will be felt, after which you will feel that the needle is fixed solidly within the bone. Remove the stylet and aspirate approximately 1 ml of unadulterated bone marrow into a syringe. Specimen is taken and is assessed for the presence of bony spicules.
If the specimen shows spicules, the specimen should be used to make smear slides immediately. If spicules are sparse or are not present, a new sample should be obtained from a slightly different site. The needle is left in place and sequential syringes are filled that have been prepared with heparin or other anticoagulants or preservatives, depending on the requirements for specific studies to withdraw samples for additional analysis. Then remove the needle, either after reinserting the stylet or with the syringe attached.
COMPLICATIONS : Hemorrhage Infection Persistent pain at the marrow site Retroperitoneal hematomas Trauma to neighboring structures (e.g., lacerations of a branch of the gluteal artery) and soft tissues