title: Ophthalmic artery pressure during retrobulbar anaesthesia.
abstract: Ophthalmic artery pressure recordings were performed before and after retrobulbar injection of 4.5 ml Xylocain-Exadrin by the use of Stepanik Arteriotonography. A 50% reduction in ophthalmic artery pulse pressure was found, which correlates well with the corresponding reduction in corneal indentation pulse amplitudes demonstrated by dynamic tonometry. The results demonstrate a shift from pulsatile towards non-pulsatile ocular blood flow. In two of the eight patients a pronounced reduction was also found in ocular perfusion pressure, indicating that retrobulbar anaesthesia may be hazardous in certain cases by initiating a major reduction in ocular blood supply. In order to minimize this hazard in eyes especially vulnerable to a reduction in ocular perfusion pressure, such as glaucomatous eyes, it is probably safest to perform retrobulbar anaesthesia with 2-3 ml of Xylocain 1% without the use of Exadrin (epinephrine).
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000772:Anesthesia, Local / Q000009:adverse effects*; D001794:Blood Pressure / Q000187:drug effects*; D004837:Epinephrine / Q000009:adverse effects; D005123:Eye / Q000098:blood supply; D005260:Female; D006801:Humans; D007267:Injections; D008012:Lidocaine; D008297:Male; D008875:Middle Aged; D009880:Ophthalmic Artery / Q000502:physiology*; D009915:Orbit; D011674:Pulse / Q000187:drug effects; D014065:Tonometry, Ocular / Q000379:methods
chemical_list: D008012:Lidocaine; D004837:Epinephrine