Technique of Puncture

Abstract

Sternal puncture is still today the easiest and most commonly used method for obtaining bone marrow. It is usually performed in midsternum at the level of the 2nd or 3rd intercostal space. After cleansing the skin and applying an antiseptic, the skin and particularly the underlying periosteum are anesthetized with a few milliliters of 1% mepivacaine hydrochloride or other anesthetic. When anesthesia has set in, a marrow puncture needle with its stylet in place and the guard set is pushed in at the selected site. As soon as the needle touches the periosteum, the guard is fixed at 4–5 mm and the cortical layer is gently pierced with slight rotation. Entry of the needle is distinctly felt, a crackling may be heard occasionally. Considerable pressure may be needed if the cortex is hard and thick. When the marrow has been entered, the stylet is withdrawn, a 10 or 20 ml syringe is affixed airtight to the puncture needle, and 0.5–1 ml bone marrow is aspirated.