Abstract and Introduction
Background Pressure ulcers are an important source of morbidity and suffering for patients and a formidable burden on caregivers.
Objectives To assess the impact of a feeding formula enriched with fish oil on healing of preexisting pressure ulcers and serum levels of C-reactive protein in critical care patients.
Methods Adult patients with pressure ulcers grade II or higher were randomly allocated to receive either a formula enriched with fish oil or an isocaloric control formula. Wound healing was assessed by using the Pressure Ulcer Scale for Healing tool on days 7, 14, and 28. Blood levels of C-reactive protein were measured on days 0, 7, and 14.
Results Baseline demographics did not differ between the study (n = 20) and the control (n = 20) groups. The mean score on the ulcer healing tool increased significantly (P = .02) from day 0 to day 28 in the control group (from 9.25 [SD, 2.12] to 10.75 [SD, 3.41]) compared with the study group (from 9.10 [SD, 2.84] to 9.40 [SD, 3.72]). Mean levels of C-reactive protein decreased significantly (P=.02) from day 0 to day 14 in the study group (from 191 [SD, 104.4] mg/L to 111.7 [SD, 97.8] mg/L) compared with the control group (from 145 [SD, 90] mg/L to 139 [SD, 62] mg/L).
Conclusion Administration of a feeding formula enriched with fish oil was associated with decreased progression of pressure ulcers and a decrease in blood concentrations of C-reactive protein.
Apressure ulcer (decubitus ulcer or bed sore) is an area of localized damage to the skin and underlying tissue caused by pressure, shear, friction forces, or a combination of these. The lesions are a marked source of morbidity and suffering for patients and a formidable burden on caregivers.[1–3] The prevalence of pressure ulcers varies widely, depending on both patient factors (eg, age, physical impairments) and the treatment setting. These ulcers are due to local breakdown of soft tissue caused by compression between a bony prominence and an external surface.[1,2] Ongoing mechanical pressure, which reduces cutaneous perfusion, and friction or shear forces act in concert to promote tissue breakdown and necrosis of muscle, subcutaneous tissue, dermis, and epidermis, with the consequent formation of pressure ulcers. These mechanical factors, as well as systemic factors, may impair wound healing, thereby contributing to the persistence of pressure ulcers.
Intensive care unit (ICU) patients are particularly predisposed to pressure ulcers because of several risk factors, including infusions of norepinephrine, scores greater than 13 on the Acute Physiology and Chronic Health Evaluation II, frequent fecal incontinence, anemia, and prolonged ICU stay. In addition, immobility, disturbed sensory perception, and malnutrition, which hampers immune function and wound healing, also increase the risk for pressure ulcers.[4,5]
In a recent study in patients with acute lung injury, those who received an enteral nutritional formula enriched with fish oil containing ω-3 light-chain polyunsaturated fatty acids (PUFAs) and micronutrients had greater improvement in oxygenation than did those who received an isocaloric control formula. The improvement in pulmonary function was attributed to the established anti-inflammatory property of the ω-3 light-chain PUFAs and micronutrients. Furthermore, the incidence of new pressure ulcers was significantly reduced by use of the specialized formula. This important finding led us to speculate that this formula might also aid in the healing of new pressure ulcers in the general ICU population. We hypothesized that attenuation of inflammation by the formula would help maintain the immune processes involved in wound healing.
The objective of this clinical trial was to assess the effect in ICU patients of a formula enriched in eicosapentaenoic acid and micronutrients on the healing of existing pressure ulcers and on acute inflammation as indicated by serum levels of C-reactive protein (CRP).
Fish oil enriched formula with anti-inflammatory properties improved oxygenation in patients with acute lung injury.
Am J Crit Care. 2012;21(4):102e-109. © 2012 American Association of Critical-Care Nurses