Abstract
Cataract surgery is among the most frequently performed and successful operations in medicine, yet its very safety and volume make its avoidable complications both easy to overlook and, in aggregate, substantial. This review examines five recurrent, foreseeable and largely preventable device-related harms of intraocular surgery that share a common structure: cannula detachment from the syringe, causing intraocular injury and visual loss; medication error arising from the poor labelling of syringes on the sterile field; thermal injury to the corneal wound from disruption of phacoemulsification irrigation flow; postoperative pressure spikes from incompletely removed viscoelastic; and expansile-gas dilution errors in vitreoretinal surgery. The first two are examined in detail, drawing on three national surveys, an independent institutional case series, a mechanistic analysis of the Luer connection, and the published record of intracameral drug error. Although clinically distinct, all five arise at the interface between compliant devices and human performance, all five are habitually attributed to individual lapse rather than to system or design failure, and all five are consequently under-recognised by the surveillance systems intended to detect them. The review argues that exhortation to greater individual vigilance sits at the bottom of the accepted hierarchy of risk control, which places inherently safe design above protective measures and both above warnings; that manufacturers and the assemblers of surgical procedure packs bear a proactive duty, engaged precisely because these failures are under-reported, to design out or, at minimum, recommend safeguards against them; and that a single, low-cost secondary safeguard applied to every syringe–cannula assembly can address two of these hazards at once, arresting the cannula in the event of connector failure while providing the mandated syringe label. Adoption of such an integrated device should be regarded as an emerging standard of care.