Indications for Administration of Parenteral Nutrition in Adults

New perspective for nutritional support of cancer patients: Enteral/parenteral nutrition

Cancer and its treatment result in severe biochemical and physiological alterations associated with a deterioration of quality of life (QoL). Cancer-related malnutrition may evolve into cancer cachexia due to complex interactions between pro-inflammatory cytokines and the host metabolism. Depending on the type of cancer treatment (either curative or palliative), the clinical condition of the patient and nutritional status, adequate and patient-tailored nutritional intervention should be prescribed (diet counseling, oral supplementation, enteral or total parenteral nutrition). Nutritional support has been widely advocated as adjunctive therapy for a variety of underlying illnesses, including surgery and medical oncotherapy (radiation or chemotherapy for cancer). Glutamine, n-3 fatty acids and probiotics/prebiotics are therapeutic factors that potentially modulate gastrointestinal toxicity related to cancer treatments. Enteral and parenteral nutrition may help improve patient survival, functional status and QoL, yet the benefits appear to be primarily limited to patients with good functional status and with gastrointestinal disease affecting nutritional intake. Parenteral nutrition offers the possibility of increased or maintenance of the nutrient intake in patients for whom normal food intake is inadequate and for whom enteral nutrition is not feasible, is contraindicated or is not accepted by the patient. This article reviews evidence on issues relevant to enteral and parenteral nutrition in patients with cancer.

Non-surgical oncology - Guidelines on Parenteral Nutrition, Chapter 19

Reduced nutritional state is associated with unfavourable outcomes and a lower quality of life in patients with malignancies. Patients with active tumour disease frequently have insufficient food intake. The resting energy expenditure in cancer patients can be increased, decreased, or remain unchanged compared to predicted values. Tumours may result in varying degrees of systemic pro-inflammatory processes with secondary effects on all significant metabolic pathways. Therapeutic objectives are to stabilise nutritional state with oral/enteral nutrition and parenteral nutrition (PN) and thus to prevent or reduce progressive weight loss. The maintenance or improvement of quality of life, and the increase in the effectiveness and a reduction in the side-effects of antitumor therapy are further objectives. Indications for PN in tumour patients are essentially identical to those in patients with benign illnesses, with preference given to oral or enteral nutrition when feasible. A combined nutritional concept is preferred if oral or enteral nutrition are possible but not sufficient. There are generally no accepted standards for ideal energy and nutrient intakes in oncological patients, particularly when exclusive artificial nutrition is administered. The use of PN as a general accompaniment to radiotherapy or chemotherapy is not indicated, but PN is indicated in chronic severe radiogenic enteritis or after allogenic transplantation with pronounced mucositis or GvH-related gastrointestinal damage for prolonged periods, with particular attention to increased risk of bleeding and infection. No PN is necessary in the terminal phase.

Nutritional intervention and quality of life in adult oncology patients

The evaluation of quality of life (QoL) assesses patients' well-being by taking into account physical, psychological and social conditions. Cancer and its treatment result in severe biochemical and physiological alterations associated with a deterioration of QoL. These metabolic changes lead to decreased food intake and promote wasting. Cancer-related malnutrition can evolve to cancer cachexia due to complex interactions between pro-inflammatory cytokines and host metabolism. Beside and beyond the physical and the metabolic effects of cancer, patients often suffer as well from psychological distress, including depression. Depending on the type of cancer treatment (either curative or palliative) and on patients' clinical conditions and nutritional status, adequate and patient-tailored nutritional intervention should be prescribed (diet counselling, oral supplementation, enteral or total parenteral nutrition). Such an approach, which should be started as early as possible, can reduce or even reverse their poor nutritional status, improve their performance status and consequently their QoL. Nutritional intervention accompanying curative treatment has an additional and specific role, which is to increase the tolerance and response to the oncology treatment, decrease the rate of complications and possibly reduce morbidity by optimizing the balance between energy expenditure and food intake. In palliative care, nutritional support aims at improving patient's QoL by controlling symptoms such as nausea, vomiting and pain related to food intake and postponing loss of autonomy. The literature review supports that nutritional care should be integrated into the global oncology care because of its significant contribution to QoL. Furthermore, the assessment of QoL should be part of the evaluation of any nutritional support to optimize its adequacy to the patient's needs and expectations.