Background
Poor hospital outcomes among adult patients admitted to hospitals have been attributed to inadequate nutrient intake and progressive disease conditions. The purpose of this study was to determine the adequacy of the intake of energy, zinc and selenium among adult inpatients receiving hospital prepared total naso-gastric blended tube feeding (NGTF).

Methods
This was a cross-sectional study that adopted quantitative approaches in data collection, analysis and presentation. A comprehensive sample of 113 adult patients, 20–65 years of age who had been on total NGTF in the previous 24 h participated in the study. Nutrient adequacy for individual patients was established using the Harris Benedict equation (HBE) and the European Society for Clinical Nutrition and Metabolism (ESPEN) daily recommendations for zinc and selenium intakes. A researcher-administered questionnaire was used to collect data on socio-economic and medical characteristics. Fourteen pairs of hospital prepared NGTFs were sampled weekly for 3 months and analysed for total energy, carbohydrate, protein, fat, zinc and selenium content using AOAC international methods.

Results
Mean total energy, zinc and selenium content for NGTF was 126.9 ± 67.0 Cal/100 ml (64.6 % carbohydrate, 23.1 % protein and 12.3 % fat), 0.13 ± 0.01 mg/100 ml and 0.09 ± 0.02 μg/100 ml respectively and this content varied significantly among the paired samples (p < 0.05). Mean volume intake of NGTF was 257.1 ± 273.0 ml/day given through scheduled gravity feeding. This resulted in a mean total energy intake of 326.5 ± 346.7 Cal/day (5.5 Cal/Kg/day), mean carbohydrate intake of 210.9 ± 223.9 Cal/day, mean protein intake of 0.3 g/Kg/day, with zinc at 0.34 ± 0.24 mg/day and selenium at 0.23 ± 0.24 μg/day. The mean total energy, protein, zinc and selenium intakes were significantly lower than the recommended values (p < 0.05). All participants had inadequate zinc and selenium intakes while only 0.88 % had adequate energy intake.

Conclusion
In this study, there was evidence of inconsistent supply of energy, carbohydrates, protein, fat, zinc and selenium to patients on naso-gastric tube feeds. Since inconsistency in supply of nutrients is associated with poor hospital outcomes, it is recommended that commercial tube formulas with known and predictable nutrient amounts be used.