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Chapter 072. Malnutrition and Nutritional Assessment (Part 2) ppt

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Chapter 072. Malnutrition and Nutritional Assessment (Part 2) Marasmus The end stage of cachexia, marasmus is a state in which virtually all available body fat stores have been exhausted due to starvation. Conditions that produce marasmus in developed countries tend to be chronic and indolent, such as cancer, chronic pulmonary disease, and anorexia nervosa. Marasmus is easy to detect because of the patient's starved appearance. The diagnosis is based on severe fat and muscle wastage resulting from prolonged calorie deficiency. Diminished skin-fold thickness reflects the loss of fat reserves; reduced arm muscle circumference with temporal and interosseous muscle wasting reflects the catabolism of protein throughout the body, including vital organs such as the heart, liver, and kidneys. The laboratory findings in marasmus are relatively unremarkable. The creatinine-height index (the 24-h urinary creatinine excretion compared with normal values based on height) is low, reflecting the loss of muscle mass. Occasionally, the serum albumin level is reduced, but it stays above 2.8 g/dL in uncomplicated cases. Despite a morbid appearance, immunocompetence, wound healing, and the ability to handle short-term stress are reasonably well preserved in most patients with marasmus. Marasmus is a chronic, fairly well-adapted form of starvation rather than an acute illness; it should be treated cautiously, in an attempt to reverse the downward trend gradually. Although nutritional support is necessary, overly aggressive repletion can result in severe, even life-threatening metabolic imbalances such as hypophosphatemia and cardiorespiratory failure. When possible, oral or enteral nutritional support is preferred; treatment started slowly allows readaptation of metabolic and intestinal functions (Chap. 73). Kwashiorkor In contrast to marasmus, kwashiorkor in developed countries occurs mainly in connection with acute, life-threatening illnesses such as trauma and sepsis, and chronic illnesses that involve acute-phase inflammatory responses. The physiologic stress produced by these illnesses increases protein and energy requirements at a time when intake is often limited. A classic scenario for kwashiorkor is the acutely stressed patient who receives only 5% dextrose solutions for periods as brief as 2 weeks. Although the etiologic mechanisms are not clear, the protein-sparing response normally seen in starvation is blocked by the stressed state and by carbohydrate infusion. In its early stages, the physical findings of kwashiorkor are few and subtle. Fat reserves and muscle mass are initially unaffected, giving the deceptive appearance of adequate nutrition. Signs that support the diagnosis of kwashiorkor include easy hair pluckability, edema, skin breakdown, and poor wound healing. The major sine qua non is severe reduction of levels of serum proteins such as albumin (<2.8 g/dL) and transferrin (<150 mg/dL) or iron-binding capacity (<200 µg/dL). Cellular immune function is depressed, reflected by lymphopenia (<1500 lymphocytes/µL in adults and older children) and lack of response to skin test antigens (anergy). The prognosis of adult patients with full-blown kwashiorkor is not good, even with aggressive nutritional support. Surgical wounds often dehisce (fail to heal), pressure sores develop, gastroparesis and diarrhea can occur with enteral feeding, the risk of gastrointestinal bleeding from stress ulcers is increased, host defenses are compromised, and death from overwhelming infection may occur despite antibiotic therapy. Unlike treatment in marasmus, aggressive nutritional support is indicated to restore better metabolic balance rapidly (Chap. 73). Although kwashiorkor in children is less foreboding, perhaps because a lesser degree of stress is required to precipitate the disorder, it is still a serious condition. Marasmic Kwashiorkor Marasmic kwashiorkor, the combined form of PEM, develops when the cachectic or marasmic patient experiences acute stress such as surgery, trauma, or sepsis, superimposing kwashiorkor onto chronic starvation. An extremely serious, life-threatening situation can occur because of the high risk of infection and other complications. It is important to determine the major component of PEM so that the appropriate nutritional plan can be developed. If kwashiorkor predominates, the need for vigorous nutritional therapy is urgent; if marasmus predominates, feeding should be more cautious. . Chapter 072. Malnutrition and Nutritional Assessment (Part 2) Marasmus The end stage of cachexia, marasmus is a state in. illnesses such as trauma and sepsis, and chronic illnesses that involve acute-phase inflammatory responses. The physiologic stress produced by these illnesses increases protein and energy requirements. is blocked by the stressed state and by carbohydrate infusion. In its early stages, the physical findings of kwashiorkor are few and subtle. Fat reserves and muscle mass are initially unaffected,

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