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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.

References                       

  1. Osher RH. Iris damage by inadvertent cannula injection. J Cataract Refract Surg 2007;33:339-41.
  2. Buys YM, Firat M, Brent MH. Posterior capsular rupture secondary to viscoelastic cannula and luer-lock release during phacotrabeculectomy. Can J Ophthalmol 2009;44:102-3.
  3. Munshi V, Sampat V, Pagliarini S. Zonular dialysis and vitreous loss with a J-shaped hydrodissection cannula during phacoemulsification. J Cataract Refract Surg 2005;31:450-1.
  4. Dinakaran S, Kayarkar VV. Intraoperative ocular damage caused by a cannula. J Cataract Refract Surg 1999;25:720-1.
  5. Prenner JL, Tolentino MJ, Maguire AM. Traumatic retinal break from viscoelastic cannula during cataract surgery. Arch Ophthalmol 2003;121:128-9.
  6. Bradshaw SE, Shankar P, Maini R, Ragheb S. Ocular trauma caused by a loose slip-lock cannula during corneal hydration. Eye (Lond) 2006;20:1432-4.
  7. Rumelt S, Kassif Y, Koropov M, Landa E, Marzuk F, Segal ZI, et al. The spectrum of iatrogenic intraocular injuries caused by inadvertent cannula release during anterior segment surgery. Arch Ophthalmol 2007;125:889-92.
  8. Ting DSJ, Vaideanu-Collins D, Ellerton C. Cannula-associated ocular injuries during cataract surgery: the North East England Study. Eye. 2016;30(5):764-765. doi:10.1038/eye.2016.3.

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