General Anaesthesia in Special Care Dentistry. Part 1: Justifying and Planning the Use of General Anaesthesia

Justification for GA

A challenge when assessing patients with special care needs who are very resistant to oral examination, including radiographic assessment, is the justification for general anaesthesia or sedation for assessment and treatment itself. Discussions with carers or families on signs that may indicate a person has a dental problem include changes in eating or sleeping patterns, increased drooling, facial tapping, swellings or a new aversion to mouthcare. For patients who accept blood tests, these may indicate the presence of infection (such as a raised white cell count or raised C-reactive protein). It is important to consider oral health risk factors and the amount and type of dental treatment that has been undertaken in the past as part of the decision-making process. Even if there are no signs of dental problems, a decision may be made to actively undertake sedation or GA for a full assessment to ensure that all dental health needs are met. This pro-active approach may be sensible for some patients because early dental disease is generally asymptomatic. Symptoms or signs of oral pain generally indicate that caries or periodontal disease has progressed substantially, which may result in the need for extraction of teeth rather than restorative care. Even in people who have had a low need for dental treatment in the past, changes, such as moving residence, and transitioning between services, can change their oral health risk factors. In these cases where a decision to provide treatment has been made with limited assessment for patients unable to consent to their care, it is best practice for a second opinion from an experienced colleague.

The advantage of GA in facilitating treatment does not mean that it should be used without consideration. Anaesthesia is associated with medical and psychosocial risks; however, the incidence of adverse outcomes is low.^12-14 For some patient groups seen within special care dentistry services, these risks may be higher. In particular, health outcomes can be worse for people with learning disabilities, especially when pre-operative assessments are limited.¹⁵ It is, therefore, essential to ensure the use of GA is justified, associated with an overall benefit to each patient and appropriately planned.

The non-exhaustive list below presents situations where the use of GA can be justified:

Patient assessment and care planning

Ideally, a comprehensive clinical examination should be undertaken in a clinical setting. This provides some insight into a possible treatment plan and supports the justification of dental treatment under GA. This also provides insight into how anxious or agitated a person may be in a dental or hospital environment. At such visits, radiographic imaging is also highly beneficial, although it may not be feasible for many patients, such as those with severe learning disabilities or autism. Some patients who cannot tolerate intra-oral imaging or an orthopantomogram may be able to cope with lateral oblique imaging (Figure 1). Although often limited, this imaging can provide some information to support the justification of a GA and an idea of what treatment may be needed with a GA.¹⁶ For some patients, examination or a brief assessment without a detailed intra-oral examination can be conducted outside the clinical setting. This could potentially be completed in a person's home, or another environment where they are comfortable, and where such a dental visit would not cause distress.

When planning treatment for patients who may need GA, the following factors should be considered:

A pre-operative anaesthetic assessment is beneficial to support anaesthetic risk assessment and plan how anaesthesia may be delivered.^17-19 Adjustments to the standard process may be necessary to support care delivery for some patients. Patients with learning disabilities or cognitive impairments will often have a hospital passport (Figure 2), a document that details useful information that can facilitate care (e.g. likes, dislikes and triggers to challenging behaviours). These can vary between NHS Trusts, yet in any format, reading the hospital passport before meeting the patient is most useful.²⁰ The passport should be available to dental, nursing and anaesthetic teams during the assessment and a copy placed in the notes, so that it is available to the dental and anaesthetic team.

Community and hospital learning disability nurses can play a vital role in supporting patients and their carers with hospital or dental appointments. They often have established relationships with individual patients and their families/carers and an understanding of their specific circumstances, level of disability and behaviours. Learning disability nurses can also advocate for their patients, provide information and support to families/carers, act as a point of contact for the patient and other healthcare services, and support patients from assessment to delivery of general anaesthetic.

Reasonable adjustments

Reasonable adjustments should be made to improve access and facilitate a successful outcome, especially for patients who present with behaviours that challenge the provision of health care.¹⁵ Some reasonable adjustments that could be considered include:

Virtual dental consultations and anaesthetic pre-assessment may be considered for patients with challenging behaviours where intra-oral or other physical examinations would not be possible in clinical settings. This minimizes hospital appointments and may improve cooperation on the day of the procedure.

For patients with behaviours that challenge, it is worth asking the following:

A social history should be undertaken; some patients may have carers for a certain number of hours, and it is important to check that overnight support can be arranged and that there is access to suitable transport to and from the hospital on the day of the procedure.

Most dental surgery is performed as day-case surgery. This is preferable because it is less disruptive to the patient and reduces the length of hospital stay and the overall cost of admission. Fitness for day surgery should not be based on an American Society of Anesthesiologists (ASA) score, age or body mass index (BMI), but on a functional assessment of the patient. A patient with a stable chronic disease, such as diabetes, is often better managed as a day-case patient because it reduces the disruption to the patient's routine with appropriate post-discharge support. If the patient is well after a period of observation, they can be safely discharged home. A pathway should exist if, unexpectedly, the patient requires an overnight admission.

Investigations

For minor dental surgery, extensive investigations are not usually necessary.^21,22 However, investigations, such as those shown in Table 1, may be requested in specific circumstances. Where these cannot be obtained pre-operatively, taking blood tests during anaesthesia as requested by the medical team can support holistic care for patients and identify unknown systemic health concerns.²³

Assessment of capacity and consent

While many conditions that mean GA is needed for dental care delivery impact a patient's cognition and mental capacity, a cognitive condition, such as a learning disability or dementia, does not automatically mean a person lacks capacity to consent to their care, including when GA is used. Legislation guides the capacity assessment process and how to proceed with care when capacity is assessed as lacking. Legislation differs across the UK, with different laws applying to England and Wales,²⁴ Northern Ireland,²⁵ and Scotland.²⁶ The key aspects of these laws are well summarized in other publications that also summarize the assessment of capacity and the approach to legally delivering treatment for those who lack the capacity to consent for it.^27,28

The key common element to relevant legislation is that a person should be assumed to have the capacity to consent unless this is assessed not to be the case. Consent is decision specific; some patients may be able to make decisions about having a tooth extracted under local anaesthetic, but not about comprehensive dental care under general anaesthetic. Person-centred care should be facilitated,²⁹ and wherever possible, patients should be actively involved in decisions about their own healthcare.^29,30 Furthermore, altered formats of information and tailored support should be considered to assist a person in making an autonomous decision.²⁹ A keynote in the Mental Capacity Act²⁴ (section 1(5)) is the reference to the need to consider whether treatment can be delivered ‘in a way that is less restrictive of the person's rights and freedom of action.’ This reiterates the need to consider whether alternatives to GA are feasible for each person. It may be that GA is the least restrictive approach by which a person's needs can be met, despite how restrictive it can be.

When capacity is assessed to be lacking, a best interests process is required to confirm whether GA is appropriate, and how this may be planned to support the individual. It is good practice for anaesthetic teams to support this process where possible, particularly where the risk of anaesthetic is heightened. This allows the risks and the route to anaesthesia to be considered collaboratively. Ideally, where multidisciplinary care is undertaken, the teams providing this should support the process of best interests decision making.

Consent for treatment will depend on whether a patient can consent to their own treatment or if treatment is planned following an appropriate best-interest decision-making process. It is important to establish whether those supporting a patient have the legal authority to consent for a patient, such as a lasting power of attorney or court appointed deputyship. In the absence of a person ‘close to the patient’ or somebody with legal authority, an independent mental capacity advocate can be appointed who can independently consider the treatment proposed, and support discussion about what may be in their best interests.

The risks of dental care and anaesthesia should be explored and discussed. In particular, the use of GA may modify the type of dental treatment delivered and may, potentially, mean teeth need to be extracted that could theoretically be restored with treatment under local anaesthesia if it was tolerated. This may include anterior teeth, and patients or carers must understand that it may not always be possible to replace front teeth and that this decision may be made after examination under anaesthetic. Treatment suitable for delivery with GA is summarized in Part 2 of this series, yet it is necessary to explain the potential treatment that may be delivered, particularly when a pre-operative examination is limited, and the nature of treatment cannot be ascertained until a patient is anaesthetized. The plan delivered with GA should, where possible, lead to an outcome that retains oral function, and retains only stable teeth at low risk of causing future pain and infection.

Multidisciplinary care

People with learning disabilities or autism can demonstrate behaviours that challenge the provision of physical investigations or treatments. Blood tests are a recommended part of the annual health check for people with learning disabilities, as many have medical comorbidities and are taking medication, such as anti-epileptic drugs, that require regular therapeutic drug monitoring. Many individuals with learning disabilities have severe anxiety about needles and have difficulty understanding the benefits of the test, resulting in challenging behaviours. If a best-interest decision has been made to proceed with a general anaesthetic for dental treatment, the dental team can liaise with families, carers and the general medical practitioner to identify whether any other procedures could be undertaken at the same time. This could be medical (blood tests, ENT examinations or vaccinations) or related to personal care, including nail cuttings, and haircuts, where it has not been possible to do so otherwise.^23,31,32 There needs to be a balance between the risks of undertaking the procedures and the holistic benefits to the patient. There can be challenges to providing multidisciplinary care, including coordinating potentially multiple medical specialities and procedures. This requires effective and organized clinical communication provided by the clinical team and learning disability nurses in the acute and community settings.

Instructions to the patient/carer

Nationally, the recommended guideline for fasting is 6 hours for solids and 2 hours for clear liquids. Use of diuretics, chronic dehydration and antihypertensive drugs may precipitate postural hypotension, especially in the fasted patient. For this reason, fasting periods should not be longer than necessary. Many units have moved to a 1-hour clear fluid fasting policy to attempt to reduce starvation times, however, the policies of individual units should be followed while considering the needs of each patient. Some patients may only accept their medication with food, for example, with yoghurt, and the anaesthetic team should discuss with the carers about omitting these medications pre-operatively and bringing them to the appointment so that they can be administered after the procedure.

It is good practice for a patient or a care team to be called a week before the operating date by a member of the dental team to discuss and confirm arrangements, including pre-medication, clinical holding, the plan for the treatment day and proposed dental treatment and to address any last-minute questions or concerns.

Do not attempt resuscitation (DNAR) orders

Patients will sometimes arrive for theatre with a ‘do not attempt resuscitation’ (DNAR) order or an advanced directive.³³ Some feel that all DNAR orders should be suspended before surgery or that clinicians put themselves at unnecessary risk by taking a patient with a DNAR order to theatre. Cardiac arrest outcomes are much better in the operating theatre than elsewhere in the hospital. Reasons include that the patient is continuously monitored with an anaesthetist standing by. However, it would be unethical to universally suspend all DNAR orders in the peri-operative period without discussion with the patient or their relatives.

Summary

Part 1 of this article described the indications for dental treatment under general anaesthesia and the adjustments that should be made as part of the pre-assessment and planning of GA. Part 2 is focused more on the practical delivery of safe and effective dental care under GA, and Part 3 discusses some case reports of the use of general anaesthesia to provide dental care in complex circumstances.