Chapter 55: Concepts of Care for Patients With Malnutrition: Undernutrition and Obesity

Undernutrition represents a state of inadequate nutrient intake leading to progressive weight loss and metabolic derangement, where the body catabolizes proteins and other tissues to meet energy demands, with marasmus representing a severe form characterized by wasting and depletion of muscle and fat stores. Obesity, by contrast, involves complex pathophysiological mechanisms including dysregulation of adipokine signaling and hormonal imbalances that place excessive strain on multiple organ systems and elevate risk for chronic diseases. Comprehensive assessment forms the foundation of nutritional care and requires precise anthropometric measurements using appropriate tools, such as sliding-blade knee height calipers for patients with limited mobility, to calculate body mass index and determine severity of malnutrition. An interprofessional collaborative approach utilizing evidence-based protocols such as the Malnutrition Readmission Prevention Protocol has demonstrated measurable improvements in patient outcomes and reduces healthcare complications. Interventions for undernutrition range from oral medical nutrition supplements to enteral nutrition delivered through various tube access routes including nasogastric, nasoduodenal, percutaneous endoscopic gastric, and direct percutaneous endoscopic jejunal tubes, with mandatory radiographic verification of tube placement before initial feeding. Parenteral nutrition administered intravenously provides an alternative when the gastrointestinal tract is not functional. Management of obesity incorporates lifestyle modification counseling, cognitive restructuring techniques to address eating behaviors and psychological factors, and surgical interventions including various bariatric surgery approaches. Post-bariatric surgery nursing care demands meticulous discharge education addressing graduated diet progression, adequate hydration maintenance, prescribed vitamin supplementation to prevent micronutrient deficiencies, vigilant monitoring for serious complications including anastomotic leaks, and dietary strategies to minimize dumping syndrome and other postsurgical complications.