Which local anesthetic block has the highest risk of hematoma after administration?

The block with the highest risk of hematoma following administration is the posterior superior alveolar (PSA) block. This block is performed to anesthetize the maxillary molars, and it involves the insertion of a needle into the region adjacent to the maxillary tuberosity, where important vascular structures can be located, including the maxillary artery and its branches.

When the needle penetrates too deep or at an improper angle, it can inadvertently damage these blood vessels, leading to bleeding and the formation of a hematoma. The anatomical proximity of large blood vessels in the area, along with the highly vascular nature of the maxillary region, contributes to the risk associated with this particular anesthetic block.

In contrast, other blocks like the inferior alveolar (IA) block, Gow-Gates (GG) block, and mental or incisive blocks involve areas with relatively fewer major blood vessels in close proximity to the injection site, thus presenting a lower risk of hematoma formation. Understanding the anatomy and potential complications of each block is crucial for minimizing risks during local anesthesia administration.