title: Letter: The prophylactic epidural blood patch.
mesh_terms: D000328:Adult; D000368:Aged; D000775:Anesthesia, Spinal / Q000009:adverse effects*; D001769:Blood; D004388:Dura Mater; D006261:Headache / Q000209:etiology / Q000517:prevention & control*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011677:Punctures / Q000009:adverse effects