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Ophthalmic Safety Alert – detachment of cannulas during ophthalmic surgery

17 April 2018

The NHS Improvement national patient safety team have informed the College of the continued trend of incidents involving issues with detachment of cannulas during ophthalmic surgery (cannula-associated ocular injury, COI). The cannula is usually attached to either a saline or a viscoelastic syringe. The combination of a small lumen and plunger pressure can result in significant hydraulic force. If the cannula does detach, it can cause extensive damage to the globe with resultant visual impairment.

The detachment may occur due to the surgeon or scrub nurse not securely attaching the two device components and a failure to check that the devices are securely attached prior to intra-ocular use.

Luer lock syringes should always be used.

Prior to intra-ocular use, the cannula and syringe should be checked to ensure that they are securely connected. The surgeon should personally check and prime the syringe prior to introduction to the section and preferably angulate the cannula away from the posterior segment. A bimanual approach can also be employed to provide additional security.


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Reproduced from with kind permission from:

Ting DS, Dees C, Ellerton C. Cannula-associated ocular injuries during cataract surgery: A preventable intraoperative complication?

Middle East Afr J Ophthalmol 2017;24:54-6