Pneumonia

Discussion

Pneumonia is defined as inflammation and consolidation of lung tissue in response to an infectious agent . Several organisms and disease conditions have been identified to infect or inflame the lungs.  The epidemiology of the disease has changed due to changes in the microorganisms and modalities used to treat the condition. The incidence of pneumonia requiring hospitalization is highest among the elderly .  Subgroups at risk for pneumonia include individuals with chronic obstructive pulmonary disease (COPD), diabetes mellitus, asthma, alcoholism, and congestive heart failure and diseases that affect the immune system (eg, HIV disease/AIDS and cancer).  Mechanically ventilated patients are at most risk for developing hospital-acquired pneumonia.

     Approximately 50% of pneumonia cases are caused by viruses and tend to be less severe than those of bacterial origin.  Pneumococcus (Streptococcus pneumoniae) is the most common cause of bacterial pneumonia.  Aspiration pneumonia results when solid or liquid food passes into the lungs, causing infection.  Aspiration pneumonia results in approximately 50,000 deaths per year, mostly in the elderly.   Nosocomial pneumonia is the leading cause of death from hospital-acquired infection in the world.  

    Prevention of pneumonia primarily includes maintenance of immune status and pneumococcal vaccination.  Treatment of pneumonia involves a combination of pharmacologic therapy (eg, antibiotics), pulmonary rehabilitation, and maintenance of nutritional status.   Protein energy malnutrition (PEM) is associated with involuntary weight loss, functional impairment and impaired immunity.  It has been demonstrated that nutritional status plays a critical role in the modulation of immune function.  In a study of 277 patients admitted to the hospital for treatment of community-acquired pneumonia, the most important factor independently associated with fatal disease was a low serum albumin level (4).  In the same study, a serum albumin level under 3.0 g/dL during treatment of the pneumonia was also associated with death due to pneumonia after discharge.  Craven and colleagues identified malnutrition as a risk factor for nosocomial pneumonia in hospitalized patients.  

Approaches

The primary goal of medical nutrition therapy in the management of pneumonia is to preserve lean body mass and immune function, prevent unintentional weight loss, and maintain nutritional status. For detailed intervention strategies, refer to the Pneumonia Medical Nutrition Therapy Protocol in Medical Nutrition Therapy Across the Continuum of Care .

Energy, Provide enough energy to maintain reasonable body weight.  Increased energy may be needed for patients with infection, fever, or weight loss.

Protein, Provide enough protein to maintain visceral protein status and meet the demands of infection.  

Fluids, Fluids are encouraged, unless contraindicated.  From 3 to 3.5 L of fluid per day has been recommended to liquefy secretions and help lower temperature in febrile patients.

    Nutrients and the immune system: Several nutrients have been linked to the preservation and maintenance of immune function.  Nutrients that have been identified include vitamins A, E, and B₆, zinc, copper, selenium, the amino acids glutamine and arginine, and omega-3 fatty acids.  These nutrients all seem to modulate specific aspects of human immune function.   Current studies do not demonstrate a direct cause and effect relationship with the incidence of pneumonia.  The current thought is that these nutrients may play a key role in the immune function, leading to less of a risk of developing pneumonia.   Currently, supplementation with these identified nutrients is not warranted.  However, it is recommended to increase the consumption of foods that provide these nutrients as good sources, such as fruit, vegetables, grains, meats, and fish. 

     Aspiration risk reduction: Instituting feeding techniques that prevent risk for aspiration may be indicated in patients who demonstrate symptoms of aspiration, such as coughing before, during, or after consumption of solids, liquids or medications; drooling; pocketing food in the mouth; and repetitive movement of the tongue from front to back of the mouth.  To reduce the risk of aspiration, consider the following strategies:

• Position patient at a 90^o angle during meals.
• Serve food at appropriate temperatures.
• Limit mealtime distractions.

Encourage small bites.

• Avoid using straws since liquids will be rushed to the back of the mouth before swallowing is safe.
• Avoid serving thin liquids, as they can be easily aspirated.  Thickened liquids will slow transit time.

 

     References

1. Marrie TJ.  Bacterial pneumonia.  In: Conn RB, Borer WZ, Snyder JW, eds. Current Diagnosis 9. Philadelphia, Pa: WB Saunders; 1997: 307-311.
2. Pneumonia. American Lung Association; 1996.   Fact sheet.
3.  White J, ed.  The Role of Nutrition in Chronic Disease Care.  Washington, DC:  Nutrition Screening Initiative; 1997:22-35..
4. Hedlund JU, Hansson LO, Ortqvist AB.  Hypoalbuminemia in hospitalized patients with community-acquired pneumonia.  Arch Intern Med.  1995;155:1438-1442.
5.  Craven DE, Steger KA, Barat LM, Duncan RA.  Nosocomial pneumonia: epidemiology and infection control.  Intensive Care Med. 1992; 18(suppl 1):S3-9.
6. Inman-Felton A, Smith K, Johnson E, eds. Medical Nutrition Therapy Across the Continuum of Care. 2^nd ed. Chicago, Ill: American Dietetic Association; 1998.
7. Escott-Stump S.  Nutrition and Diagnosis-Related Care. 5th ed.  Baltimore, Md: Lippincott Williams & Wilkins; 2002:199.
8. Romore MM.  Vitamin A as an immunomodulating agent.  Clin Pharm.  1993;12:506-514.
9. Chandra RK.  Effect of vitamin and trace element supplementation on immune responses in elderly subjects.  Lancet. 1992;340:1124-1127.
10. Neidert KC, ed. Nutrition Care of the Older Adult.  Chicago, Ill: American Dietetic Association; 1998:213.