Key Points
- Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
- Set objective targets (hemodynamic, neurologic, respiratory) and reassess frequently.
- Plan definitive source control or reperfusion when indicated; document follow‑up and patient education.
Algorithm
- Diagnose clinically; check IOP and vision.
- Initial drops: timolol + α2-agonist; give acetazolamide 500 mg IV/PO.
- Add pilocarpine once IOP begins to fall; repeat topical agents per protocol.
- If inadequate, give IV mannitol; antiemetics/analgesia.
- Urgent ophthalmology for laser peripheral iridotomy; treat fellow eye prophylactically when indicated.
Clinical Synopsis & Reasoning
Painful red eye with halos, mid-dilated pupil, corneal edema, and high IOP. Lower pressure with sequential topical and systemic therapy and arrange urgent laser peripheral iridotomy in both eyes when appropriate.
Treatment Strategy & Disposition
Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced or procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.
Epidemiology / Risk Factors
- Risk varies by comorbidity and precipitants; see citations for condition‑specific data.
Investigations
| Test | Role / Rationale | Typical Findings | Notes |
|---|---|---|---|
| Tonometry (IOP) | Diagnosis/severity | Markedly elevated | Track response |
| Gonioscopy (if available) | Angle status | Closed/narrow angle | Specialist skill |
| Slit lamp exam | Cornea/anterior chamber | Edema, shallow chamber | — |
Pharmacology
| Medication/Intervention | Mechanism | Onset | Role in Therapy | Limitations |
|---|---|---|---|---|
| Timolol 0.5% 1 drop | β-blocker (topical) | Minutes | ↓ Aqueous production | Contraindicated in asthma/heart block |
| Apraclonidine/Brimonidine 1 drop | α2-agonist (topical) | Minutes | ↓ Aqueous production | Dry mouth, fatigue |
| Pilocarpine 1–2% 1 drop (after IOP starts to fall) | Miotic | Minutes-hours | Opens angle via pupillary constriction | Ineffective when IOP very high initially |
| Acetazolamide 500 mg IV/PO | Carbonic anhydrase inhibitor | Hours | ↓ Aqueous production | Avoid in sulfa allergy; renal dosing |
| Mannitol 1–2 g/kg IV | Osmotic diuretic | Hours | Rapid IOP reduction if refractory | Monitor volume/osmolality |
Prognosis / Complications
- Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.
Patient Education / Counseling
- Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.
References
- AAO Preferred Practice Pattern: Primary Angle Closure (2020) — Link