Anesthesia Considerations for Cataract Surgery

1. Preoperative Considerations

A. Patient Assessment

  • Age Consideration: Most patients are elderly and may have comorbidities (hypertension, diabetes, ischemic heart disease, COPD).
  • Systemic Evaluation:
    • Cardiovascular status (e.g., ECG, echocardiography in severe cases)
    • Respiratory status (assess COPD, asthma)
    • Endocrine disorders (diabetes mellitus is common)
    • Renal function (in elderly or diabetic patients)
  • Medications:
    • Anticoagulants/antiplatelets: Typically continued in topical anesthesia but reviewed for regional anesthesia.
    • Antihypertensives: To be continued; avoid ACE inhibitors/ARBs on the day of surgery to prevent hypotension.
    • Antidiabetics: Adjust insulin/oral hypoglycemics accordingly.

B. Ophthalmic Considerations

  • Presence of glaucoma (can affect choice of drugs like succinylcholine).
  • Risk of intraoperative floppy iris syndrome (IFIS) in patients on tamsulosin (a selective alpha-1A blocker for BPH).
  • Narrow-angle glaucoma is a relative contraindication for mydriatics.


2. Anesthetic Techniques

A. Regional Anesthesia (Preferred in Most Cases)

  1. Topical Anesthesia (Most Common)
    • Drugs Used: Proparacaine 0.5%, tetracaine 0.5%, or lignocaine 2% gel.
    • Advantages:
      • No risk of retrobulbar hemorrhage or globe perforation.
      • Faster recovery and fewer systemic complications.
    • Limitations:
      • May not be sufficient for longer or complicated surgeries.


  1. Peribulbar Block
    • Technique:
      • Injection of 5-7 mL of local anesthetic in the inferotemporal and superior nasal region.
    • Drugs Used: Lignocaine 2% + Bupivacaine 0.5% ± Hyaluronidase.
    • Complications:
      • Globe perforation
      • Retrobulbar hemorrhage
      • Optic nerve injury
      • Increased intraocular pressure (IOP)
  1. Retrobulbar Block (Less Commonly Used)
    • Injection Site: 3 mL of local anesthetic in the muscle cone.
    • Complications:
      • Retrobulbar hemorrhage
      • Optic nerve damage
      • Brainstem anesthesia (via optic nerve sheath)
  1. Sub-Tenon’s Block
    • Technique: 2-4 mL local anesthetic injected into the Tenon’s capsule.
    • Advantages: Lower risk of hemorrhage and globe perforation than retrobulbar block.


B. General Anesthesia (Indications and Considerations)

  • Indicated in:
    • Pediatric patients
    • Uncooperative adults (e.g., dementia, movement disorders)
    • Complex surgeries requiring long operative time
  • Induction Agents:
    • Propofol is preferred (smooth induction and rapid recovery).
    • Avoid ketamine in glaucoma (as it increases IOP).
  • Muscle Relaxation:
    • Succinylcholine avoided in open globe injuries.
    • Rocuronium with sugammadex preferred for rapid reversal.
  • Maintenance:
    • Sevoflurane or TIVA (Total Intravenous Anesthesia).
  • Airway Considerations:
    • Avoid coughing/bucking as it increases IOP.
    • LMA preferred over endotracheal intubation in short procedures.


3. Intraoperative Concerns

A. Intraocular Pressure (IOP) Considerations

  • Increased IOP Causes:
    • Hypertension, hypercarbia, hypoxia
    • Coughing, straining, laryngoscopy
    • Suxamethonium (via extraocular muscle contraction)
  • Reduction Strategies:
    • Adequate depth of anesthesia
    • IV mannitol (for acute lowering of IOP)
    • Avoiding Trendelenburg position

B. Cardiovascular Stability

  • Oculocardiac Reflex (OCR):
    • Triggered by traction on the extraocular muscles or orbital structures.
    • Manifestation: Bradycardia, hypotension, asystole.
    • Management:
      • Stop stimulus.
      • Give IV atropine (0.01 mg/kg) if persistent.
      • Ask surgeon to infiltrate LA at the surgical site.

C. Monitoring Considerations

  • Standard ASA monitoring.
  • Capnography essential if GA is used.
  • Avoid high peak airway pressures (can increase IOP).


4. Postoperative Considerations

  • Pain Management:
    • Usually minimal; managed with paracetamol/NSAIDs.
    • Avoid opioids unless necessary (can cause nausea/vomiting).
  • Nausea and Vomiting:
    • Risk Factors: Female gender, opioid use, motion sickness history.
    • Prophylaxis: Ondansetron or dexamethasone.
  • Complications to Watch For:
    • Corneal abrasions (if eyes are not lubricated properly).
    • Delayed recovery in elderly or those with pre-existing cognitive issues.


6. MCQs for Exam Preparation

  1. Which of the following is NOT a risk factor for intraoperative floppy iris syndrome (IFIS)?
    a) Tamsulosin
    b) Finasteride
    c) Propranolol
    d) Doxazosin
    Answer: c) Propranolol
  2. Which drug should be avoided in a patient with glaucoma undergoing cataract surgery?
    a) Propofol
    b) Rocuronium
    c) Ketamine
    d) Midazolam
    Answer: c) Ketamine
  3. Which of the following is TRUE regarding peribulbar block?
    a) Less risk of globe perforation than retrobulbar block
    b) Injected within the muscle cone
    c) Causes rapid onset motor block
    d) Does not require hyaluronidase
    Answer: a) Less risk of globe perforation than retrobulbar block
  4. Which anesthetic technique has the lowest risk of retrobulbar hemorrhage?
    a) Retrobulbar block
    b) Peribulbar block
    c) Sub-Tenon’s block
    d) General anesthesia
    Answer: c) Sub-Tenon’s block