ABSTRACT
This retrospective audit of 87 consecutive patients undergoing routine cataract surgery compared the effect of peribulbar local anaesthesia using 16 mm and 25 mm, 25 gauge needles to administer the anaesthetic. The effect on optic nerve function was observed. There was a significant increase of complete amaurosis in the group where the 16 mm needle had been used. This may be explained by more effective anatomic placement of the 16 mm needle within the orbit, allowing access to the retrobulbar space via fascial septae. There was significantly more lid akinesia with the 16 mm needle. None of this group required an additional facial nerve block, as opposed to 14% of the 25 mm needle group. The use of a 16 mm needle is theoretically safer than a 25 mm needle to administer a peribulbar anaesthetic, in this review it was also demonstrated to be more effective.
Subject(s)
Anesthesia, Local/methods , Cataract Extraction , Needles , Aged , Equipment Design , Female , Humans , Male , Middle Aged , Nerve Block , Retrospective StudiesABSTRACT
Six thousand consecutive patients in whom retrobulbar anesthesia was performed by an anesthesiologist before ophthalmic surgery were studied. Sixteen patients (1 in 375) developed signs and symptoms presumed to be caused by the direct spread of the local anesthetic agents to the central nervous system. These signs and symptoms ranged from drowsiness, blindness of the contralateral eye, abnormal shivering, or vomiting, through to respiratory depression, apnea, hemiplegia, aphasia, convulsions, unconsciousness, and cardiopulmonary arrest. The severity of the symptoms was unrelated to the dose of anesthetic administered. The time of the onset of symptoms after the retrobulbar injection was variable (average 8 min, range 2 to 40 min). The possibility of a life-threatening complication occurring was rare (1 in 750) but unpredictable. The need for closely monitored anesthesia care of all patients having surgery under retrobulbar anesthesia is stressed.
Subject(s)
Anesthetics, Local/adverse effects , Central Nervous System Diseases/chemically induced , Nerve Block/adverse effects , Ophthalmologic Surgical Procedures , Anesthetics, Local/administration & dosage , HumansABSTRACT
The present study was conducted in 100 patients receiving retrobulbar block for ophthalmic surgery to compare the efficacy of local anesthetic solutions with and without hyaluronidase. All patients received 3.5 ml of a mixture of 3 ml of 0.5% bupivacaine and 2 ml of 2% lidocaine. Seventy-five international units of hyaluronidase were diluted in 5 ml of the local anesthetic mixture and used for 50 of the blocks. The remainder did not receive hyaluronidase. A consistently better motor blockade was achieved with hyaluronidase (P less than 0.001 at 10, 15, and 20 min). This finding has not been conclusively demonstrated before.
