VTE Prophylaxis for Opthalmology Surgery patients - Reducing the risk of venous thromboembolism

Publication: 01/08/2010  
Next review: 01/08/2024  
Clinical Guideline
ID: 2046 
Approved By: Trust Clinical Guidelines Group 
Copyright© Leeds Teaching Hospitals NHS Trust 2021  


This Clinical Guideline is intended for use by healthcare professionals within Leeds unless otherwise stated.
For healthcare professionals in other trusts, please ensure that you consult relevant local and national guidance.

VTE Prophylaxis for Opthalmology Surgery Patients

Treatment pathway document


Reducing the risk of venous thromboembolism (deep vein thrombosis and pulmonary embolism) in patients admitted to hospital undergoing ophthalmic surgery:-

  • Squint surgery
  • Cataract Surgery
  • Vitreo-retinal surgery
  • Trabeculectomy/tube implants
  • Oculoplastics
  • Lid procedures and cysts
  • Corneal surgery including grafts
  • Dacryocystorhinostomy

To provide evidence-based recommendations for appropriate venous thromboembolism (VTE) risk assessment and management of patients admitted to hospital for ophthalmic surgery

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NICE clinical guideline 92; Venous thromboembolism: reducing the risk was issued in January 2010, updated June 2015 and replaced by NICE guideline NG89 Venous thromboembolism in over 16s: reducing the risk of hospital-acquired deep vein thrombosis or pulmonary embolism in March 2018

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Risk Assessment

Leeds Teaching Hospitals risk assessment tool used for all patients undergoing a general anaesthetic, those requiring admission but no surgery and for those undergoing a local anaesthetic with post-op posturing.

NICE states that patients having surgery with local anaesthesia administered by local infiltration with no limitation of mobility should not be routinely offered pharmacological or mechanical VTE prophylaxis. Local anaesthesia in ophthalmology is such a limited area it can be counted as infiltration and therefore these patients will be cohorted out of VTE risk assessment unless they have surgery which required post operative posturing which limits mobility for 3 hours.

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Treatment / Management

Clinical algorithm - (see treatment pathway document).

The majority of ophthalmic patients are day case patients and ophthalmic operations are usually quite short (cataracts 20 minutes, trabeculectomies and tube implants 60 minutes and retinal and corneal up to 90 minutes). The mobility of patients is not significantly reduced with the patient walking to and from the theatre post surgery. The exceptions to this are when patients have to have post surgical posturing which limits mobility for up to 3 hours. Therefore patients undergoing a local anaesthetic without post operative posturing are cohorted out of risk assessment. Operations requiring posturing are vitreo-retinal surgery and corneal surgery with descemet stripping (automated) endopthelial keratoplasty (DSEK and DSAEK).

All patients requiring a general anaesthetic and those admitted as an in patient but not requiring surgery will be risk assessed on admission using Leeds Teaching Hospitals risk assessment tool. This should be completed electronically via PPM+. The VTE risk assessment should be repeated 24 - 48 hours post admission, at Consultant review and whenever their clinical condition changes, as per NICE guidance.

As any significant intra-operative or post-operative bleeding in ophthalmic surgery can affect the successful outcome of the surgery and may affect patient’s sight low molecular weight heparin preparations should not be used.

All patients at moderate or high risks are given anti-embolism stockings providing they do have not any contra-indications.

Anti-embolism stockings are contra-indicated if there is:-

  • Suspected or proven peripheral arterial disease
  • Peripheral arterial bypass grafting
  • Peripheral neuropathy or other causes of sensory impairment
  • Any local conditions in which anti-embolism stockings may cause damage – for example, fragile 'tissue paper' skin, dermatitis, gangrene or recent skin graft
  • Allergy to the material of manufacture
  • Severe leg oedema
  • Major limb deformity or unusual leg size or shape preventing correct fit
  • Acute stroke

Certain patients with a history of thrombophilia or hyperviscosity syndromes may require low molecular heparin preparations after discussion with a consultant haematologist. These patients are exceptional and are outside the remit of these guidelines but will be easily identified prior to listing or on acute admission.

Ophthalmic patients admitted as in-patients but no surgery planned (e.g. corneal ulcers for intensive antibiotic treatment) will be assessed using Leeds Teaching Hospitals risk assessment tool. This should be completed electronically via PPM+. VTE risk assessment should be repeated 24 - 48 hours after admission, at consultant ward round and whenever the patients clinical condition changes.

Patients with a medium/high risk of VTE, will be prescribed anti-embolism stockings and providing they have no risk factors for bleeding prophylactic enoxaparin, see dosing chart detailed below. If LMWH prophylaxis is indicated it should be prescribed and administered within 14 hours of admission. These measures will continue until the patient is fully mobile.

Enoxaparin Dosing for patients with creatinine clearance (CrCl) over 30mL/min


Dose of Enoxaparin


20mg daily

50 - 100kg

40mg daily

101 - 150kg

40mg twice daily


60mg twice daily

Enoxaparin Dosing for patients with creatinine clearance (CrCl) less than 30mL/min


Dose of Enoxaparin


20mg daily with caution - consider Factor Xa levels

50 - 100kg

20mg OD daily

101 - 150kg

40mg OD daily


60mg OD daily

Patient Information
All patients should be given verbal and written information about their risk of VTE on admission, this should include what will happen, side effects and how they can help to reduce the risk. On discharge they should be given verbal and written information about the signs and symptoms of VTE and what to do should they occur; they should also be given instructions on how to use their thromboprophylaxis if required on discharge and how long it should continue for. Leaflet LN004075 contains this information and is available to order from the print unit

Information for Discharge
Notify the patient's GP if they have been discharged with pharmacological and/or mechanical VTE prophylaxis to be used at home

All heparins are porcine based
If patients do not want a porcine based product consider fondaparinux 2.5mg s/c once a day reduced to 1.5mg s/c once a day if CrCl 20-50ml/min) Contra-indicated if CrCl < 20ml/min. Do not use if the patient has a latex allergy.

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Monitoring for Heparin Induced Thrombocytopenia (HIT)
All patients started on any type of heparin should have a baseline platelet count performed. For patients who have received heparin of any form in the previous 100 days a platelet count at 24 hours is advised. Further monitoring is not required for patients on low molecular weight heparin (LMWH). If HIT is suspected please refer to the Guideline on Diagnosis and Management of HIT
This is based on national guidance from the British Committee for Standards in Haematology November 2012.

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Record: 2046
Clinical condition:

Various ophthalmic conditions (Cataracts, squints, vitreo-retinal surgery, trabeculectomy/tube implants, oculoplastics, lid procedures and cysts, corneal procedures and grafts )

Target patient group: All ophthalmic patients.
Target professional group(s): Secondary Care Doctors
Adapted from:

Evidence base

NICE guidelines

Approved By

Trust Clinical Guidelines Group

Document history

LHP version 1.0

Related information

Not supplied

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