A nurse is assessing a 45-year-old factory worker who presents to the emergency department with a metallic foreign body in the right eye. What is the most important initial assessment the nurse should perform?

Assessing for signs of globe penetration is the most important initial assessment because it determines if immediate surgical intervention is needed to prevent vision loss. Other actions (checking visual acuity, irrigating, applying pressure) are contraindicated or secondary until penetration is ruled out.

Understanding the Priority: Why "Assess for Globe Penetration" Comes First

When a patient presents with a metallic foreign body in the eye, the immediate nursing priority is not to restore function or cleanse the wound, but to determine the structural integrity of the globe itself. An open globe injury (OGI) is a full-thickness wound of the eyewall and constitutes a vision-threatening emergency. The initial assessment must rule this out before any intervention that could cause further harm. The systematic review by Mair et al. highlights that detecting an OGI and any associated intraocular foreign body (IOFB) is a critical preoperative step, as the presence of a rupture or laceration fundamentally changes the management pathway ^[1].

The Danger of Premature Intervention

Options 1, 2, and 3 are contraindicated as initial actions if an OGI is suspected, because they can exacerbate the injury:

- Checking visual acuity (Option 1): While a standard part of an eye exam, asking a patient to squeeze their eyelids shut to read an eye chart can increase intraocular pressure (IOP). In an eye with a penetrating wound, this pressure spike can cause extrusion of intraocular contents, converting a salvageable injury into irreversible vision loss. The EXTRACCT guideline emphasizes a structured approach where a thorough history and inspection for penetration precede any manipulative examination in ocular trauma .
- Irrigating the eye (Option 2): Irrigation is appropriate for chemical burns or superficial foreign bodies, but it is dangerous for a suspected open globe. The fluid stream can introduce bacteria deeper into the eye, and the mechanical force can further disrupt delicate tissues. The guideline notes that management of an open globe focuses on protecting the eye with a rigid shield and preventing any pressure, not irrigation .
- Applying pressure (Option 3): This is an absolute contraindication. Direct pressure on a traumatized eye with a possible rupture will almost certainly expel the vitreous humor, retina, or uveal tissue. The case report by Saleem et al. on penetrating ocular trauma reinforces the principle that any increase in IOP must be meticulously avoided, from the moment of injury through surgical repair ^[3].

Clinical Significance of a Metallic Foreign Body and Occult Injury

A metallic foreign body from a factory setting, such as a metal shard from hammering or grinding, is a high-velocity projectile. The force of impact is often sufficient to cause a penetrating injury that may not be immediately obvious. The entry wound can be small, self-sealing, and hidden under a subconjunctival hemorrhage or eyelid edema. The case reports by Ngo et al. on transorbital orbitocranial penetrating injuries (TOPI) illustrate a critical point: a seemingly minor external wound can mask a deep, life-threatening trajectory where the object has traversed the orbit and entered the intracranial cavity . Therefore, the nurse's assessment must be guided by a high index of suspicion. The primary survey involves gross inspection for signs of OGI, which include:

- A teardrop-shaped or peaked pupil, indicating iris prolapse.
- Extrusion of dark uveal tissue or clear vitreous gel.
- A shallow anterior chamber compared to the unaffected eye.
- A positive Seidel sign (fluorescein dye diluted by aqueous humor leaking from the wound, visible under cobalt blue light), though this may be omitted if the globe is obviously ruptured.

If any of these signs are present, the immediate nursing action is to stop the assessment, place a rigid eye shield over the eye without applying pressure, elevate the head of the bed to 30 degrees, and prepare the patient for emergent ophthalmology consultation and operative repair. The systematic review confirms that imaging, such as a CT scan, is the definitive next step to identify the IOFB and determine the extent of the injury, but the nurse's clinical assessment at the bedside is what triggers this life- and sight-saving sequence ^[1].