Anaesthesia options for cataract surgery

Most cataract surgery is done awake with local anaesthesia. The “best” option depends on comfort, anxiety, surgeon preference, and eye factors such as ability to lie still.

Topical Sub‑Tenon’s Peribulbar Retrobulbar Sedation / GA

Sub‑Tenon’s block schematic showing blunt cannula and anaesthetic spread — Sub‑Tenon’s anaesthesia (schematic illustration). If this diagram is insufficient, see a detailed reference image: external image.

What matters most

Good outcomes require a still eye, controlled pain, and a calm patient. Discuss your priorities (comfort vs recovery speed vs “numbness”) before the day of surgery.

Local techniques (overview)

Technique	What it does	Pros	Cons / risks
Topical ± intracameral	Drops to numb the surface; sometimes local anaesthetic inside the eye.	Fast recovery; no needle around the eye; less bruising.	Eye can still move; pressure sensation can remain; relies on cooperation.
Sub‑Tenon’s block	Blunt cannula delivers local anaesthetic into the sub‑Tenon’s space.	Good comfort; lower risk of deep needle complications; reduces movement.	Bruising/chemosis; rare globe injury; very rare spread causing systemic effects.
Peribulbar block	Local anaesthetic injected around (not inside) the muscle cone.	Good akinesia; widely used for longer/complex cases.	Needle risks (haemorrhage, perforation); higher volume; rare brainstem spread.
Retrobulbar block	Local anaesthetic injected inside the muscle cone (deep block).	Dense akinesia and anaesthesia.	Higher risk profile: retrobulbar haemorrhage, globe perforation, optic nerve injury, rare brainstem anaesthesia.

Sedation (“twilight”) and monitored care

Often used to reduce anxiety and improve tolerance of lights/pressure sensations.
Usually light to moderate: you breathe on your own and can follow instructions.
Risks: oversedation (airway obstruction), low oxygen, low blood pressure, nausea, delirium in susceptible patients.
Tell your team about sleep apnoea, opioid use, alcohol use, and prior sedation issues.

General anaesthesia (GA)

Less common for routine cataracts; may be chosen for severe anxiety, inability to lie flat, tremor, certain cognitive issues, or complex surgery.
Pros: complete immobility and no awareness.
Cons: longer recovery; higher systemic risk than local in many patients; airway instrumentation; aspiration risk.

Block-related complications (what to watch for)

Retrobulbar / orbital haemorrhage (rapid swelling, pain, tight eyelids).
Globe perforation (rare; risk rises in long eyes / high myopia).
Optic nerve injury (very rare).

Brainstem anaesthesia (very rare): drowsiness, breathing difficulty, weakness.
Local anaesthetic systemic toxicity (very rare with eye blocks).
Oculocardiac reflex (slow heart rate with ocular traction).

In practice, serious complications are uncommon; the point is to understand trade‑offs and choose an approach that fits your risk profile and comfort needs.