Skill List > Nutritional Assessment
Clinical Alert
Elsevier Clinical Skills covers the principles of this procedure. You must follow local policies and procedures regarding technique, equipment used and documentation.
Authors:
Based on Nicol: Essential Nursing Skills 4E
Adapted by: Patricia Cronin BSc(Hons) MSc PhD DipN(Lond) RN
Updated by: Patricia Cronin BSc(Hons) MSc PhD DipN(Lond) RGN
Last updated: July 2017
Learning Objective
After reading the skill overview, watching the animation, following up some of the references/web sites and completing the self-test quiz you should be ready to be assessed in practice in the skill of assessing nutrition.

Introduction

Good nutrition is essential not only to promote health and well-being, but also to aid recovery from trauma, surgery, or disease. Yet, malnutrition is common among those who are ill whether they are in hospital or in the community. People who are unwell may not eat or drink what they should, or their ability to do so may be impaired due to the nature of their illness. Malnutrition is referred to as a state in which a deficiency of nutrients causes measurable adverse effects on body function and/or clinical outcome (National Collaborating Centre for Acute Care (NCCAC) 2006). Although malnutrition or ‘bad nutrition’ associated with over-eating is also an important issue for nurses undertaking nutritional assessment, the focus of much of the literature has been on under-nutrition. Poor nutritional status is known to be associated with delayed recovery and adverse outcomes of illness and injury (NCCAC 2006). The National Institute for Health & Care Excellence (NICE) (2012) declare malnutrition is an important issue of patient safety that continues to be under-detected and undertreated and which can have potentially fatal consequences. 

Although other staff are involved, nurses have a primary responsibility to ensure patients in their care have adequate nutrition and hydration (Nursing & Midwifery Council (NMC) 2010, 2015). They have an important role in the prevention of malnutrition through identifying those at risk and planning care to meet their needs (Pegram & Bloomfield 2015). In addition, they must ensure those who are initially well-nourished do not become malnourished while in hospital. Fundamental to the provision of adequate and appropriate nutritional care is ongoing nutritional assessment. 

The responsibility of nurses to identify malnutrition is well-defined in the NMC essential skills clusters. In order to develop effective plans of care for the management of nutrition and fluid intake all patients must be screened on admission and where necessary a comprehensive nutritional assessment for malnutrition undertaken (Pegram & Bloomfield 2015). 


Nutritional assessment tools

Although most hospitals have developed a tool to assist in nutritional assessment and the identification of those at risk, the NCCAC recommends use of the five-step Malnutrition Universal Screening Tool (MUST) (Todorovic et al. 2003, NCCAC 2006, Elia 2012) because it is relatively simple to use and has some validation. It is a five-step tool that includes the following:

  • Body Mass Index (BMI).
  • Unplanned weight loss in the last 3–6 months.
  • Subjective criteria (such as those outlined below).
  • Once overall risk is established, use of local guidelines and/or policies to develop appropriate care plans.

Body Mass Index (BMI) is a tool for use with patients over 18 years old and helps determine if the patient has a normal weight, is underweight, or is overweight. However, it is important to note that BMI is an estimate of health because body shape and muscle mass can influence the result (Wild 2012). Therefore, on its own it is not a good indicator of nutritional risk and needs to be used in conjunction with other measures. BMI is calculated by dividing the weight in kilograms by the height in metres squared (see below).

If the patient’s height cannot be measured, the demispan of the arm (half the distance between the patient’s hands outstretched to either side), ulna height, or knee height can be used to estimate height. These measurements can be converted using the guides in the MUST explanatory booklet (Todorovic et al. 2003).

If height and weight cannot be measured, BMI can be estimated using mid upper arm circumference (MUAC). If the upper arm circumference is less than 23.5 cm, it is likely the BMI is less than 20 kg/m². If it is more than 32.0 cm, the patient’s BMI is likely to be more than 30 kg/m²  (Todorovic et al. 2003).

A BMI of 20–24.9 indicates an average or desirable weight. A BMI of greater than 30 is classified as obese, and greater than 40 as grossly obese. Patients with a BMI of less than 20 may show signs of under-nutrition. It is important to note, however, that patients who are overweight or obese can also be malnourished.

 
BMI   =   weight in kg   = 
60   =  20.01
(height in metres)² 1.69 x 1.69

 

In addition to the BMI, most nutritional assessment tools will incorporate consideration of the following factors, which are known to increase the risk of malnutrition (NCCAC 2006, Lloyd-Jones 2015, Pegram & Bloomfield 2015):

  • Age: Older adults are vulnerable to under-nutrition and its incidence rises with age irrespective of illness. A decline in lean body mass (LBM) reduces basal metabolic rate by 10–15% or more after 50 years old. Loss of LBM enhances morbidity and mortality; impacts on cardiac, respiratory, and muscle function; reduces body temperature (hypothermia); and increases the risk of falls and subsequent injury.
  • Mental condition: Any deterioration in mental state or consciousness level is likely to affect the patient’s desire and ability to eat and drink independently, and so will increase the risk of malnutrition. This includes patients who may be depressed, lethargic, or apathetic.
  • Weight: It is important to note whether there has been any recent weight loss, particularly if it is unintentional. This may be apparent from loose-fitting clothes, rings, or dentures. Patients who appear thin or emaciated are at an increased risk of malnutrition. Less than 5% weight loss in 6 months is not significant. Between 5–9% is significant only if the patient is already malnourished. Between 10–20% is clinically significant and requires intervention. More than 20% weight loss may require long-term support.
  • Appetite: Patients who are able to maintain their usual appetite and eating habits are less likely to be at risk than those who have a poor appetite or refuse meals and drinks. It is important to check whether the patient has altered their eating habits recently.
  • Functioning of the gastrointestinal tract: The presence of diarrhoea or constipation may affect the desire to eat and drink and may also lead to malabsorption. Nausea and vomiting may also result in a reduced nutritional intake. Patients who are unable to take oral food or fluids following surgery involving the gastrointestinal tract or who have conditions that affect it, such as intestinal obstruction, will be at high risk.
  • Skin and pressure ulcers: Dry and scaling skin may be an indication of dehydration and possibly related malnourishment. The existence of pressure ulcers is significant and is often included in nutritional assessment tools. Pressure ulcers are regularly associated with poor nutrition and healing pressure ulcers requires increased nutritional intake.
  • Dexterity: It is important to assess whether patients have the ability and manual dexterity to procure and prepare food and eat and drink independently.
  • Other factors: A number of conditions will affect the ability to eat and so will increase the risk of developing malnutrition. These include:
    • neurological conditions, especially those affecting coordination or mental state
    • difficulty swallowing (dysphagia) (e.g., after stroke) and malabsorption
    • surgery or major trauma
    • malignant disease and chronic conditions, such as chronic obstructive pulmonary disease
    • reduced mobility or confinement to bed
    • bereavement, depression, or other mental ill health.

When undertaking nutritional assessment the nurse should utilise the skills of ‘looking, listening and feeling’ (Wild 2012) to gather the evidence of the patient’s overall status. For example, observing whether the patient appears thin or has loose fitting clothes or jewellery, listening carefully to their daily eating and drinking habits and what influences them and/or feeling or touching a patient’s skin can provide valuable information for determining the patient’s nutritional well-being. 

Most nutritional assessment tools involve a scoring system that allocates a score for each of the possible contributing factors. The total score will indicate whether the patient is at risk; appropriate measures can then be taken. Whether a high score indicates a high or a low risk will vary between different assessment tools. Patients identified as high risk should be referred to a dietician and nutritional support should be considered for those who are malnourished or at risk of becoming malnourished (NCCAC 2006).

Patients must be assessed within 24 h of admission. The frequency of further assessments should be determined by the result of the initial assessment, for example, if a patient is well nourished on admission to hospital, weekly reassessment is adequate. However, if the nutritional assessment score indicates at-risk then reassessment may need to be within 48 h.

Nutritional support

The NCCAC (2006) guidelines state that oral, enteral, or parenteral nutritional support, either alone or combined, should be considered for people who are malnourished or at risk of malnourishment. They define malnourished as:

  • A body mass index (BMI) of less than 18.5 kg/m².
  • Unintentional weight loss greater than 10% within the last 3–6 months.
  • A BMI of less than 20 kg/m² and unintentional weight loss greater than 5% within the last 3–6 months.

Risk of malnutrition is defined as:

  • Having eaten little or nothing for more than 5 days and/or likely to be eating little or nothing in the next 5 days or longer.
  • Where there is an increased nutritional need, where the capacity for absorption is reduced, or where there is a high nutrient loss.

Preparation and safety

  • Patients must have a nutritional assessment undertaken within 24 h of admission.
  • Explain the procedure to the patient to gain consent and cooperation.
  • Perform hand hygiene.
  • Wear additional personal protective equipment where necessary.
  • Take appropriate documentation to the bedside.

Procedure

  1. Ask or measure the patient’s height and weight to plot them on the chart to calculate the BMI.
    Rationale – Body Mass Index (BMI) is a tool for use with patients over 18 years old and helps the nurse determine if the patient has a normal weight, is underweight, or is overweight.
  2. Ask the patient:
    1. if they have had any recent unplanned weight loss
    2. whether they have noticed their clothes or rings becoming loose
    3. whether their appetite has changed
    4. whether there is any change in their bowel movements
    5. if they have nausea or vomiting.
      Rationale – These factors are known to increase the risk of malnutrition (NCACC 2006, Lloyd-Jones 2015, Pegram & Bloomfield 2015). Unintentional weight loss can be significant and impact on the patient’s nutritional status. Diarrhoea or constipation can affect the desire to eat and drink and may also lead to malabsorption. Nausea and vomiting are also likely to result in a reduced nutritional intake.
  3. Consider the following:
    1. Age.
      Rationale – Older adults are vulnerable to under-nutrition and its incidence rises with age, irrespective of illness.
    2. Mental condition.
      Rationale – Any deterioration in mental state or consciousness level may affect the patient’s desire and ability to eat and drink independently and so will increase the risk of malnutrition. This includes patients who may be bereaved, depressed, lethargic, or apathetic
    3. Skin and signs of dehydration and pressure ulcers.
      Rationale – Dry and scaling skin may be an indication of dehydration and possibly related malnourishment. The existence of pressure ulcers is significant as these are regularly associated with poor nutrition. Healing pressure ulcers requires increased nutritional intake.
    4. Dexterity.
      Rationale – It is important to assess whether patients have the manual dexterity to be able to eat and drink without assistance. If the patient wears dentures, check that these fit well.
    5. Other conditions that affect the patient’s ability to eat and drink.
      Rationale – Patients who are unable to take oral food or fluids following surgery involving the gastrointestinal tract or who have conditions that affect it, such as intestinal obstruction, will be at high risk. Patients with neurological conditions, who have difficulty swallowing, or with malignant or chronic conditions are also at high risk.

Ongoing care, monitoring and support

  • Calculate the score according to local policy.
  • Patients who are identified as being at high risk should be referred to a dietician.
  • Nutritional support should be considered for patients who are malnourished or at risk of becoming malnourished NCCAC 2006).
  • A food chart may need to be maintained, and a care plan may be required for assisting the patient with eating and drinking.
  • The frequency of further assessments should be determined by the result of the initial assessment, for example, if a patient is well nourished on admission to hospital then weekly reassessment is adequate. However, if the nutritional assessment score indicates at-risk then reassessment may need to be within 48 h.

Documentation and reporting

  • Document the nutritional assessment according to local policy.
  • Refer patients who are high risk to a dietitian.
Your email :


Recipient: (email address)
To multiple recipients, separate email addresses with commas.


Note : (optional)