40% of patients may be malnourished on admission to hospital and their nutritional status has been shown to deteriorate further during their stay (1). Hospitals can become so focused on curing disease that they ignore the foundations of good health.
Malnutrition has been shown to have an adverse effect on clinical outcomes. Malnourished patients have longer hospital stays and increased morbidity and mortality than those who are well fed. This effect has been shown among medical, surgical, orthopaedic and elderly patients. Doctors and nurses often fail to recognise malnutrition because they are not trained to look for it (2).
Effects Of Malnutrition.
- Impaired muscle function (including cardiac and respiratory muscles) (3,4)
- Impaired wound healing (5)
- Impaired immunity (6)
- Impaired GI structure and function (7)
- Deterioration in mental function (8)
- Higher incidence of post-op complications (9)
- Association with increased length of stay and increases costs (10)
- Increased Mortality and Morbidity (2)
Why Are So Many Hospital Patients Malnourished?
- Increased nutritional requirements (eg sepsis, surgery, burns)
- Increased nutritional losses (eg malabsorption, high output stoma)
- Decreased intake (eg dysphagia, sedation, coma)
- Effect of treatment (eg nausea, diarrhoea)
- Enforced starvation (eg prolonged periods of nil by mouth)
- Missing meals for investigations
- Difficulty with feeding and no one available to give enough help
- Unappetizing food
Identifying The Malnourished Patient
Recent studies have highlighted how ineffectively patients are screened for nutritional status on admission to hospital. Early assessment of hospitalised patients is essential to identify those that are or may become at risk of developing disease-related malnutrition.
The British Association of Parenteral and Enteral Nutrition (BAPEN) recommended that nursing and junior medical staff carry out the following simple nutrition screening procedure on all patients on admission to hospital (13):
Weight and height are recorded and documented in nursing and medical notes.
All patients are asked the following questions:
- Have you lost weight recently?
- Have you been eating less than usual?
- What is your normal weight?
- How tall are you? (Used to estimate Body Mass Index: weight Kg / Height m2).
Clinical examination may also reveal signs of muscle wasting and loss of sub-cutaneous fat.
(More detailed screening tools are in use on certain wards)
Patients should be considered malnourished or at risk of developing malnutrition if they have an inadequate nutrient intake for > 7 days or if they have a weight loss of > 10% of their pre-illness weight (11).
Albumin is a poor marker of nutritional status and should not be used in isolation as it is affected by many other factors (12).
Prevention Of Malnutrition
Patients who are considered to be high risk should be referred to the Dietitian.
Patient’s nutritional status should be monitored throughout their stay by weekly weights and monitoring of food intakes. They should be offered appetising, nutrient dense foods and nutritional supplements utilised if not meeting requirements with diet alone. If it is not possible to maintain adequate nutrition orally then enteral feeding (nasogastric, nasoduodenal, nasojejejunal, gastrostomy, jejunostomy) should be considered.
Parenteral Nutrition (TPN).
Indications For Parenteral Nutrition
The only absolute indication for parenteral nutrition (TPN) is intestinal failure.
The gastrointestinal tract is the preferable route for feeding and enteral feeding should always be considered first. Enteral feeding is more physiological and eliminates the potential hazards associated with central line insertion (pneumothorax, infection leading to sepsis). Other complications include: hepatobiliary abnormalities; GI atrophy and subsequent bacterial translocation, potentially leading to systemic infection and multiple organ failure; and immunosuppression.
TPN should be considered in individuals exposed to 7 or more days of starvation, where feeding via the enteral route is not possible eg. bowel obstruction. Those patients with malnutrition or metabolic stress who are anticipated to be at risk of such duration of restricted intake merit earlier intervention.
There is no clinical benefit if TPN is used for < 5 days
- McWhirter JP, Pennington CR. Incidence and recognition of malnutrition in hospital. Br Med. J 1994; 308: 945-948
- Lennard-Jones JE (Ed). A positive approach to nutrition as treatment, 1992. King’s Fund Centre, 11-13 Cavendish Square, London W1M 0AN.
- Pickard C, Jeejeebhoy KN. Muscle dysfunction in malnourished patients. Quart J Med. 1988; 260: 1021-1045.
- Arora NS, Rochester DF. Respiratory muscle strength and maximal voluntary ventilation in undernourished patients. Ann Rev Resp Dis 1982: 126: 5-8.
- Haydock DA, Hill GL. Impaired wound healing in surgical patients with varying degrees of malnutrition. J Parent Ent Nutr 1986; 10: 550-554.
- Chandra RC. Immunity and infection. In: Kinney JM, Jeejeebhoy KN, Hill GL, Owen OE, Eds. Nutrition and Metabolism in Patient Care. 1988. WB Saunders & Co, Philadelphia. 598-604.
- Allison SP. Malnutrition in hospital patients. Hospital Update 1995; 55-62
- Brozek J. Effects of generalised malnutrition on personality. Nutrition 1990; 6: 389-395.
- Windsor JA, Hill GL. Protein depletion and surgical risk. Aust NZJ Surg 1988; 58: 711-715
- Reilly JR, Hull SF, Albert N, Waller A, Bringardener S. Economic impact of malnutrition: a model system for hospitalised patients. J Parent Ent Nutr 1988; 12:371-376.
- ASPEN Board of Directors. Guidelines for the use of parenteral and enteral nutrition in adult and paediatric patients. J Parent Ent Nutr, 1993, 17; 4, Supplement.
- Carpentier YA, Barthel J, Bruyns J. Plasma protein concentrations in nutritional assessment. Proc Nutr Society 1982; 41: 405-417.
- Lennard-Jones JE, Arrowsmith H, Davison C, Denham AF, Micklewright A. Screening by nurses and junior doctors to detect malnutrition when patients are first assessed in hospital. Clin Nutr 1995; 14: 336-340.