Chapter 3: Mental Capacity and Consent

Learning objectives for this chapter

This chapter will cover multiple aspects of patient care, and by the end of the chapter you should be able to:

- Define and explain the terms capacity and consent

- Identify conditions and scenarios where capacity may be impaired

- Understand how capacity can be assessed using formal assessment tools

- Appreciate the link between ethical nursing and issues surrounding capacity and consent.

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Defining capacity and consent

Capacity is the ability of an individual to make their own decisions. There are four main elements to capacity, and failure to meet any one of these elements suggests that the patient lacks the capacity to make the decision:

  1. The patient must understand the information provided to them.
  2. The patient must be able to retain the information for long enough to make the decision.
  3. The patient must be able to weigh up the information.
  4. The patient must be able to communicate their decision.

Nurses need to obtain consent for almost all interactions with patients - particularly when performing examinations, making care decisions or deciding on other aspects that may affect their wellbeing or health.

The Mental Capacity Act serves as a form of protection for patients who lack the capacity to make decisions. There are five main principles to the Mental Capacity Act:

  1. Capacity should always be assumed- the diagnosis, appearance or behaviour of a patient should not make you presume that capacity is absent.
  2. Assessment of capacity requires optimisation of the patient's ability to make decisions- sufficient time must be given, and sign language or interpreters may be important.
  3. Patients can make unwise decisions- capacity relates to the process of making a decision, not the final decision the patient makes.
  4. Decisions made for people lacking capacity should consider their best interests.
  5. Decisions made should be the least restrictive for patient rights and freedoms.

Decision-making requires balancing the needs of the patient, the rights of the patient and the patient's views in this manner, when capacity can be demonstrated.

Causes of mental impairment

Mental impairment may be caused by a number of factors in clinical practice. For each of these, patients may be affected in different ways and the impact on their capacity can vary. Some are described below:

Learning disabilities

Patients with learning disabilities may have varying levels of mental impairment. You should not make assumptions based on their appearance or diagnosis. Often, patients with learning disabilities do have the capacity to make small decisions about their everyday life, including what to do, what to wear or what to eat. For major decisions, particularly about care, these patients may not have capacity, as they may not be able to understand or retain information and weigh up the positive and negative impacts.

Mental health problems

Mental health problems may include generalised anxiety disorder, bipolar disorder, depression and schizophrenia. Patients with these conditions may be in the acute phase of their illness, or in the chronic or recovery phase, where symptoms are less pronounced. When acutely unwell, patients may not be able to demonstrate capacity for a number of reasons. Patients who are depressed may also favour no intervention on the basis that they do not wish to preserve their life or are apathetic towards outcomes. Therefore, decision-making may be impaired in some instances. However, in the recovery or chronic phase of mental health conditions, when patients are objectively 'well', capacity may be preserved and consent can be given for many, if not all, decisions.

Stroke or other brain injuries

Depending on a stroke's location, the patient's speech, understanding or cognition may be adversely affected. In patients who cannot communicate effectively (e.g. poor speech), they may not be able to express their capacity to make decisions. Every attempt should be made to try and communicate with the patient, but when this is not possible, a professional should act and make decisions based on the best interests of the patient. Patients who can communicate after a stroke may have difficulty comprehending language, or difficulty in remembering information. Either of these scenarios may reduce the potential for capacity.

As well as stroke patients, you may encounter other patients in practice who have brain injuries due to trauma or disease. The same principles should apply to these patients, and capacity should be assessed in a formal manner. Furthermore, capacity should be reassessed as the patient's condition changes or improves.

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Confusion or drowsiness

Confusion and drowsiness are often seen in patients on the medical ward. Confusion may be related to an infectious process in elderly patients, may be the result of medication, or may have developed following brain injury. Similarly, drowsiness may be caused by medication use or brain injury. It is important to determine if the cause is immediately reversible to allow patients to make care decisions.

Where reversible causes are not present, many patients will be unlikely to understand the information presented to them. Furthermore, they may find it difficult to communicate their decision.

Alcohol and substance misuse

The effects of chronic misuse of alcohol and other substances can be severe in terms of reducing memory, the ability to process information, perceptions of reality, and communication. However, cognition may be preserved - particularly following clearance of the substance. Therefore, capacity should be assessed, and chances for a patient to provide consent optimised. This may involve waiting for the patient to become sober, prior to making important clinical decisions. The delay in this process and the need for urgent medical intervention should be balanced, however.

It is important that you do not judge patients and assume things about their mental status; a complete assessment of capacity is needed to prevent discrimination and to preserve the rights of the most vulnerable groups.

Fluctuating consent

Some patients may not be able to provide consent to procedures or interventions at all times, and some patients may only be able to provide consent in certain scenarios. Just because consent was successfully obtained on one occasion, it does not mean that the patient has capacity to provide consent on other occasions.

Fluctuating capacity or consent describes situations where the patient may be able to give consent at some times, but not at others. This is particularly important in patients with confusion caused by medications, mental health issues which are resolving, or substance/alcohol misuse. The clinical state of the patient may change over time. It is important to consider two key points:

  1. The assessment of capacity must be performed when the patient's ability to make decisions is optimised
  2. In the presence of fluctuating capacity, re-assessment of the patient should be performed in a timely manner and clearly recorded.

In order to optimise the patient's potential to give capacity, the specific condition of the patient should be accurately recorded in the notes. Certain measures can be used to increase the opportunity for patients to understand, process or communicate information. This may include allocating extra time to the patient during the assessment, using communication aids, or providing assistance and additional resources to help with comprehension.

Different conditions are more likely to be related to fluctuations in capacity, and these should prompt nurses to consider re-assessment of capacity at a later time. After re-assessment, clinical decisions should be based on the most recent assessment of capacity. Further examinations may be performed over time as the patient's condition progresses or improves.

Assessment of capacity

The assessment process is of vital importance. Patients with any condition that may impair capacity should be actively engaged in a capacity assessment, not only when they disagree with a medical course of action. This is consistent with the ethics of nursing practice.

Several considerations should be noted when determining capacity; these are discussed below:

Who should assess capacity?

The Mental Capacity Act does not specify who should assess capacity. However, any health professionals who intends to be actively involved in patent care should be suitably skilled and prepared to perform capacity assessments. Ultimately, it is the responsibility of the healthcare professional who is actively treating the patient to ensure that capacity has been assessed appropriately.

How should capacity be assessed?

There is no one 'correct' way to assess the mental capacity of a patient in all scenarios. The level of capacity assessment is commonly related to the importance of the clinical decision. An example of a more detailed need for capacity assessment may be in the context of a patient receiving a surgical intervention, where there may be large risks associated with the procedure itself.

The Mental Health Act recommends the use of a functional test of capacity, which focuses on the decision-making process itself. The four main principles of capacity (understanding, retention, weighing up and communication) should be sought in a formal environment and recorded appropriately. When an individual patient fails one or more aspects, then the entire test is considered a 'fail' and capacity is not present.

The capacity assessment may be considered within the context of the information provided by friends and close family members, although their views should not be taken into consideration during the assessment process. The assessment must not be discriminatory in any way, and should not be based on the patient's age or appearance, or the nurse's assumptions.

How should capacity be documented and communicated?

The process of formal capacity assessment is very important from a professional, and potentially legal, perspective; therefore, accurate record keeping and documentation should be at the core of any assessment. This allows you to objectively record any discussions that took place and provides evidence of decisions that were made at the time.

Documentation of capacity assessments should be made formally in the patient notes and there are often specific forms to complete, depending on local policy. Once the capacity assessment is complete, nurses should communicate this to other members of staff who may be involved in the care of that patient. This can avoid confusion among staff members and variations in the patient is approached.

What are the implications of the capacity assessment?

Assessment of capacity is an important aspect of how decisions can be made. There are two distinct outcomes: the patient has capacity, or the patient lacks capacity. When the patient has capacity, their decisions should be respected. You may discuss issues with patients and try to persuade them to undergo a procedure or test. However, you must not coerce or bully them into a decision.

When the patient is found to lack capacity, they are considered unable to make a definitive care decision. However, a constructive decision-making process should be undertaken on behalf of the patient. The patient may have previously known preferences or attitudes towards specific procedures (prior to losing capacity) which may be taken into account. However, in most cases, the clinical team should make a decision based on upholding the basic rights of patients, and the decision should be made with their best interests at heart, upholding ethical principles.

What if a patient refuses to be assessed?

A patient whose capacity is in doubt may refuse to be assessed. This is a delicate situation; you should manage it sensitively and with respect. Most of the time, a sensible discussion of why the assessment is needed may be enough to persuade the patient to agree. You should explain the consequences of a patient refusing to undergo a capacity assessment, including the fact that any decisions made may be questioned by medical or legal staff in the future. However, if the patient refuses, then they cannot be forced to undergo a capacity assessment, and their wishes should be respected.

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In summary, this chapter has provided an overview of the importance of capacity and consent in nursing practice. Capacity is a key issue when exploring how patients are able to contribute to the decision-making process in a person-centred care environment. Patients who lack capacity cannot give their consent to a procedure or treatment course and therefore care must be provided in accordance with the best interests of the patient. Nurses need to use a unique set of skills, knowledge and judgment in order to ensure that patient rights, wellbeing and holistic aspects of care are achieved when capacity is lacking. The use of formal assessment processes, accurate documentation and ethical or legal processes is essential to ensuring that optimal care can be achieved.

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