ENTERAL NUTRITION IN THE PREVENTION AND TREATMENT OF PRESSURE ULCERS IN ADULT CRITICAL CARE PATIENTS Jill Cox, RN, PhD, APN-C, CWOCN Louisa Rasmussen, BS, RD, CNSC Critical Care Nurse Savannah Berry, GSU Dietetic Intern

Pressure Ulcer Localized injury to the skin, the underlying tissue, or both, usually over a bony prominence, that develops as a result of pressure or pressure in combination with shear. 2.5 million patients annually 14% to 27% highest among hospitalized patients: critical care patients

Risk Factors Altered mobility Moisture Friction or shear Older age Prolonged length of stay in the ICU Emergency admission to the ICU Use of vasopressor agents Comorbid conditions: diabetes mellitus, infection, and cardiovascular or vascular disease

Pressure Ulcer Staging System Type of Pressure Ulcer Description Suspected deep tissue injury Purple localized area of discolored intact skin (bruising) Stage IIntact skin with nonblanchable redness of a localized area typically over a bony prominence. Stage IIPartial-thickness loss of dermis manifested as a shallow open ulcer with a red pink wound bed (open blister) Stage IIIFull-thickness tissue loss. Only subcutaneous fat may be visible Stage IVFull-thickness tissue loss with exposed bone, tendon, or muscle. UnstageableFull-thickness tissue loss in which the base of the ulcer is covered by slough or eschar in the wound bed.

Research Thus Far Acute lung injury, receiving mechanical ventilation: development of pressure ulcers was significantly less when given enteral formula enriched with micronutrients, eicosapentaenoic acid (EPA or omega 3 fatty acid), and gamma- linolenic acid (omega 6 fatty acid) Stage II or higher pressure ulcers: progression was significantly less when given formula enriched with fish oil than isocaloric formula.

Malnutrition Imbalance of energy, protein, and other nutrients Nonsevere or severe based on: Insufficient energy intake Weight loss Loss of muscle mass Loss of subcutaneous fat Localized or generalized fluid accumulation Diminished functional status (hand grip strength) However, currently there is no ideal lab tests to detect malnutrition Albumin, prealbumin, transferrin, and retinol-binding protein values vary based on fluid, protein, infection, and inflammation.

Micronutrients in Wound Healing PhaseDurationImpact of Nutritional Deficiencies InflammatoryBegins at time of the injury or within 4-6 days Vit A: Alterations in immune function; increased risk of infection Vit C & Iron: Impaired immune response Zinc: decreased immunity, increased susceptibility to pathogenic organisms ProliferativeDay 3 or 4 & continues for 2- 3 weeks Vit C, iron, copper, zinc, manganese: impaired tensile strength and collagen synthesis Hypoproteinemia: impaired fibroblast proliferation and collagen synthesis Vit C: increased capillary wall and fragility and angiogenesis, increased risk of wound hemorrhage Maturation/Re modeling Day 21 and continues up to 2 years Vit A: impaired collagen synthesis Vit C: reduced tensile strength Zinc: impaired wound strength, decreased fibroblast proliferation, collagen synthesis, & epithelialization rate

Nutrition Guidelines Critical care patients should be fed ideally within the first hours after ICU admission Enteral Feedings: Ability of the gastrointestinal tract to absorb the nutrients provided in the feeding Comorbid conditions Feeding tolerance (may be reduced d/t gastric emptying) Feedings should be calorically dense, protein- rich, and provide daily requirements of micronutrients

Macronutrients Energy: kcal/kg to a max of 40 kcal/kg Protein Pressure ulcer healing: g/kg Stage III/IV: g/kg (depending on size and amt of protein loss from draining wounds) Fluid Stage I/II: >30 mL/kg per day Stage III/IV: mL/kg per day *Adjusted for fluid losses No specific recommendations of carbohydrates or fats based on pressure ulcer

Micronutrients Vitamin A (any stage): 10,000 to 50,000 IU for 10 days Taking steroids should be considered Vitamin C Stage I/II: mg/d Stage III/IV: 1000 to 2000 mg/d Renal failure: mg/d Zinc: 220 mg bid for days May need more if patient has any fluid losses (ex: small intestinal fluid, stool output, ileostomy)

Amino Acid Supplementation Arginine and glutamine Limited evidence Wound healing ability is minimal Arginine: caution in critically ill patients with sepsis because it can contribute to unstable hemodynamic status

Administration of Enteral Nutrition and Pressure Ulcers Underfeeding: Increase risk for pressure ulcers Increased risk for nosocomial infection Loss of lean body mass Prolonged duration of weaning from mechanical ventilation Delayed wound healing in patients with existing pressure ulcers Can cause diarrhea or high gastric residual volumes Feeding within hours of admission More likely 2 to 8 days Patients only received ~ 63% of their estimated energy needs

Diarrhea Not necessarily caused by enteral nutrition Medications with a sorbitol base Clostridium difficile Bacterial overgrowth in the gastrointestinal tract Intolerance to the formula used for feeding Enteral feeding should only be discontinued if all other causes are ruled out

Nursing Be sure to keep skin clean and dry from infectious substances Elevate the head during feedings (30-45°) to prevent aspirations Be sure to check sacral and buttocks regions

CAN WE FEED? C: critical care severity A: age N: nutrition risk screening W: wait for resuscitation E: energy requirements F: formula selection E: enteral access E: efficacy D: determination of tolerance Used by critical care team to determine if a patient is ready for tube feeding

Conclusion Early referral to a RD is the essential first step in improving nutritional outcomes for patients to be at risk for nutrition and pressure ulcers If a pressure ulcer is found, vitamins A, C, and zinc are crucial to the healing process More research needs to be done to verify the effectiveness of arginine and glutamine in pressure ulcer healing