Outpatient preoperative oral nutritional support for undernourished surgical patients: A systematic review

AIMS AND OBJECTIVES: To evaluate the effects of preoperative nutritional support using a regular diet for undernourished surgical patients at the outpatient clinic. BACKGROUND: Undernutrition (or malnutrition) in surgical patients has severe consequences, that is, more complications, longer hospital stay and decreased quality of life. While systematic reviews show the effects of oral nutritional supplements (ONS), enteral and parenteral nutrition in surgical patients, the effects of normal foods and regular diets remain unclear. DESIGN: A systematic review. METHODS: PubMed, CINAHL, Web of Science, PsycINFO, Cochrane Library and EMBASE were searched up to July 24, 2017. Studies on undernourished patients receiving nutritional support using regular or therapeutic diet, performed preoperatively at the outpatient clinic, were considered eligible. Risk of bias was assessed using the Cochrane Risk of Bias tool. Two reviewers independently performed study selection, quality assessment and data extraction. RESULTS: Six studies with moderate risk of bias were included. Interventions were preoperatively performed in mainly oncological outpatients by dieticians and aimed to reach nutrient requirements. Interventions included consults for counselling and advice, follow-up meetings and encouragements, and ONS. Nutritional status, nutrient intake and quality of life improved in supported patients. Improvements were better in counselled patients compared to patients using supplements. Unsupported patients experienced worse outcomes. CONCLUSION: Frequent consults with counselling and advice as nutritional support for undernourished patients before surgery result in improvements to nutritional status, intake and quality of life. This statement is supported by weak evidence due to few studies and inadequate methods. RELEVANCE TO CLINICAL PRACTICE: Nutritional support should be provided to all undernourished surgical patients during preoperative course. Nurses are in key position to provide nutritional support during outpatient preoperative evaluations.