Prophylactic gastrostomy placement and early tube feeding may limit loss of weight during chemoradiotherapy for advanced head and neck cancer, a preliminary study.

OBJECTIVES: Most patients with advanced head and neck cancer receiving chemoradiotherapy need tube feeding for at least some weeks. For these periods gastrostomy tubes have advantages over nasogastric tubes. Tube feeding may start earlier and thus loss of weight may be limited if the gastrostomy tube already is in place. The objective of this study is to analyse the results of prophylactic percutaneous endoscopic gastrostomy (PEG) tube placement and early tube feeding. DESIGN: Retrospective chart review. SETTING: Multidisciplinary head and neck oncology team in a general hospital. PARTICIPANTS: Fifty consecutive patients with unresectable stage III and IV head and neck cancer treated with concurrent chemoradiotherapy. In all patients prophylactic PEG placement was performed. Tube feeding was initiated if food-intake became insufficient or loss of weight occurred. MAIN OUTCOME MEASURES: Loss of weight during treatment, complication rate, PEG duration. RESULTS: The mean loss of weight during treatment for all patients was only 2.8%. One complication of tube placement occurred: a colon perforation, treated successfully by surgery. The median duration of the PEG was 178 days. Three of the 17 patients (18%) with no evidence of disease (NED) still had a PEG at their last follow-up visit. Of the 26 patients who died of their cancer, 13 used the PEG until death. CONCLUSIONS: Loss of weight was limited after prophylactic gastrostomy placement and early tube feeding. Moreover, the complication rate was low. In 82% of the NED patients the PEG could eventually be removed.

Relationships between in situ protein degradability and grass developmental morphology.

The objective of this research was to determine the relationships between the morphological development and in situ ruminally degradable protein (RDP), ruminally undegradable protein (RUP), and microbial protein of two cool season grasses (intermediate wheatgrass and smooth bromegrass) and two warm season grasses (switchgrass and big bluestem). The initial growth of grass tillers grown near Mead, Nebraska was clipped at ground level six times during the 1992 growing season and morphologically classified. Mean stage was calculated. Forage was ground to pass a 2-mm screen and was incubated in ruminally fistulated steers for 16 h. The RUP was adjusted for microbial protein and acid detergent insoluble N. The mean stage of cool season grasses was higher than that of warm season grasses throughout the growing season. The RDP decreased as plant maturity increased for all species. The RUP expressed as a percentage of crude protein for the cool season grasses was lower than that for warm season grasses. The RUP for intermediate wheatgrass, smooth bromegrass, and switchgrass remained constant across maturities, but RUP for big bluestem decreased as maturity increased. Microbial augmentation of RUP decreased as crude protein decreased in all species. The RUP corrected for acid detergent insoluble N and microbial protein was relatively constant across plant maturities. The quantification of RUP across a range of plant maturities provided information for incorporating RUP content of forage grasses into the diets of animals.

Ruminal degradation of switchgrass, big bluestem, and smooth bromegrass leaf proteins.

Two in situ protein disappearance experiments were conducted to determine disappearance rates of leaf protein fractions and characterize individual leaf protein fractions that escaped ruminal degradation. Fresh leaf blades of two warm-season grasses, switchgrass (Panicum virgatum L.) and big bluestem (Andropogon gerardii Vitman), and one cool-season grass, smooth bromegrass (Bromus inermis Leyss.), were included in Exp. 1. Only warm-season grasses were used in Exp. 2. Leaves were harvested from greenhouse-grown plants, placed in polyester bags, and incubated up to 48 h in situ in three ruminally fistulated steers fed diets of warm-season grass hay. The rate of protein disappearance for switchgrass (.037 h-1) was slower (P < .10) than that for big bluestem (.110 h-1). Big bluestem and smooth bromegrass (.169 h-1) disappeared at similar rates, whereas switchgrass disappeared more slowly (P < .05) than smooth bromegrass in Exp. 1. Rates of protein disappearance in Exp. 2 were similar for switchgrass (.112 h-1) and big bluestem (.116 h-1). Major protein fractions that resisted ruminal degradation in both experiments, detected using SDS-PAGE, were at approximate molecular weights of 56, 26, and 24 kDa. For switchgrass and big bluestem, total protein and individual protein fractions were generally at higher concentrations and present for longer periods of time than for smooth bromegrass. This suggests that a mechanism may exist in C4 species that allows certain protein fractions to remain undegraded for longer periods compared with smooth bromegrass.