A member of the NICE guideline development group highlights the important issues from the latest evidence-based guideline for readers of Nursing Times
Keywords: Ophthalmology, Chronic open angle glaucoma, Ocular Hypertension
Chronic open angle glaucoma (COAG) is a condition characterised by changes to the optic nerve head and typical visual field defects, with or without elevated intraocular pressure. It affects approximately 2% of the population over the age of 40 years, and accounts for one of the largest group of chronic eye diseases seen in a hospital eye department.
Management of this condition varies nationally, not least in the way ophthalmic services are organised and delivered. Thousands of people with or at risk of developing this potentially blinding form of glaucoma will benefit from the new NICE guideline, which sets out how best to diagnose and manage the condition. Early diagnosis of COAG and careful monitoring or treatment can slow down the progression of the disease and save sight.
The NICE (2009) guideline covers adults with a diagnosis of COAG or ocular hypertension (consistently elevated intraocular pressure, greater than 21mmHg, in the absence of optic nerve damage or visual field defect) and COAG and ocular hypertension (OHT) associated with pseudoexfoliation or pigment dispersion. It makes recommendations on how people are diagnosed and monitored and considers both surgical and pharmacological treatments in terms of clinical and cost-effectiveness.
The guidance particularly examines the tests that should be performed for the purpose of diagnosing and monitoring and the frequency by which patients should be monitored, considering risk factors. Uniquely, it also considers aspects of service provision and in so doing its scope extends to who should be looking after this group of patients.
While the cost-effectiveness of treatments is considered, the recommendations provide sufficient flexibility for clinicians to use judgement with regard to the choice of therapies.
What the guideline does
- Reaffirms the need for gonioscopy at diagnosis to assess angle depth and configuration to exclude angle closure.
- Identifies Goldmann applanation tonometry as the reference standard for assessing intraocular pressure.
- Establishes the need to measure central corneal thickness, as this is particularly relevant in OHT when assessing risk of conversion to COAG.
- Recommends treatment for people with OHT who are considered to be at significant risk of converting to COAG. As well as central corneal thickness, other risk factors highlighted include intraocular pressure and age.
- Evaluates the effectiveness of different treatment options, including complementary and alternative treatments.
- Uses high-quality evidence on which to base its recommendations.
- Guides healthcare professionals as to what information patients need in order to be sufficiently informed and empowered to make decisions about their care.
- Acknowledges the limitations of available quality evidence and provides recommendations for further research.
What the guideline means to nurses
The guideline recognises and acknowledges the important role healthcare professionals play in managing this group of patients. It provides guidance on the knowledge, skills and expertise professionals need in order to practise safely and provide high-quality care.
Many ophthalmic nurses are involved in managing COAG and OHT and the guideline provides a framework to ensure that their practice is evidence-based and of a high standard. It states that healthcare professionals involved in the diagnosis of OHT and COAG suspect status should be trained in case detection and be able to identify abnormalities based on the relevant clinical tests. They must also be able to interpret the outcome of assessments such as automated perimetry, stereo biomicroscopy and gonioscopy. Different models of service delivery exist and many ophthalmic nurses, working under the supervision of a consultant ophthalmologist, are already involved in glaucoma clinics. They have extensive experience of both referral refinement and monitoring.
Nurses are also well placed to educate and counsel patients about their condition, treatment and the need for lifelong monitoring
The guideline says that healthcare professionals involved in monitoring and treating OHT, suspected COAG and established COAG should be trained to make clinical decisions on risk factors for conversion from OHT and in detecting change in clinical status. They should also have pharmacological knowledge of intraocular pressure-lowering medication and be aware of the relevant contraindications and interactions. This is especially pertinent when nurses act as independent prescribers.
However, the guideline says that diagnosis of COAG should be made by a consultant ophthalmologist. This was felt to be particularly important, as confirming or excluding the diagnosis of glaucoma has serious consequences for people referred for suspected glaucoma.
Nurses are also well placed to educate and counsel patients about their condition, treatment and the need for lifelong monitoring. While the condition is not curable it can be effectively controlled so that sight may be preserved. Nurses can play a vital role in allaying anxiety while emphasising the importance of the individual’s role in their own management, particularly regarding the instillation of drops.
Ophthalmic nursing roles are constantly evolving and the guideline provides a framework whereby nurses can work in partnership with other healthcare professionals, enhancing the care for this group of patients.
AUTHOR Mary Freeman, MA, MBA, OND, RGN, is nurse consultant – ophthalmology, Sheffield Teaching Hospitals NHS Trust
NICE (2009) Diagnosis and Management of Chronic Open Angle Glaucoma and Ocular Hypertension. London: NICE.