Impact of hypocaloric and hypo-nitrogen parenteral nutrition on clinical outcome in postoperative patients: a multi-center randomized controlled trial of 120 cases

Abstract

To evaluate the impact of hypocaloric and hypo-nitrogen parenteral nutrition (PN) on infective complication rate, postoperative hospital stay and treatment cost in postoperative period. 120 patients with gastrointestinal tumors with the Nutrition Risk Screening (NRS) score of 3 or 4 undergoing radical gastrectomy in 5 hospitals were randomly assigned into 2 equal groups: control group, receiving PN with 30 (28 - 32) kcal x kg(-1) x d(-1) and nitrogen 0.20 (0.19 - 0.21) g x kg(-1) x d(-1) in regular "3 liter bag", and study group receiving calorie of 18 (range 16 - 20) kcal x kg(-1) x d(-1) and nitrogen of 0.10 (0.09 - 0.11) g x kg(-1) x d(-1) with triple chamber bag. PN support was infused continuously for at least six postoperative days through peripheral vein or peripherally inserted central catheter. The differences between these two groups in blood glucose level, infectious complication, phlebitis, systemic inflammatory response syndrome (SIRS), and duration of hospital stay after operation, and treatment cost. All data were evaluated by both intention to treat (ITT) analysis and per protocol (PP) analysis. There were no significant differences in the clinical baseline and operative types between the two groups. ITT analysis showed that the occurrence of hyperglycemia in postoperative period in the control group was 43.3%, significantly much higher than that in the study group (6.6%, P = 0.000). The infectious complication rate of the study group was 3.3%, significantly lower than that of the control group (16.6%, P = 0.0149), the phlebitis rate of the study group was 0.0%, significantly lower than that of the control group (18.3%, P = 0.0005). The SIRS rate of the study group was 25.0%, significantly lower than that of the control group (45.0%, P = 0.0216). PP analysis showed that the postoperative duration of hospital stay of the control group was 14.1 days +/- 5.8 days, significantly longer than that of the study group (12.4 days +/- 4.0 days, P = 0.047), the total PN cost of the study group was 3411.6 +/- 181.1 Yuan RMB, significantly higher than that of the control group (2945 +/- 162 Yuan RMB, P = 0.000); but the total post-operative cost of treatment of the control group was 13156 +/- 3282 Yuan RMB, significantly higher than that of the study group (11 642 +/- 3019 Yuan RMB, P = 0.010); and the time for compounding of the study group was 5.0 min +/- 1.7 min, significantly shorter than that of the control group (15.4 min +/- 3.7 min, P = 0.000). Hypocaloric and hypo-nitrogen PN in postoperative days 1 - 6 in patients with scores 3 or 4 decreases the rates of hyperglycemia, infectious complications, phlebitis, and SIRS, shortens the postoperative hospital stay, and lowers the cost of treatment comparing with conventional PN. The use of triple chamber bag shortens the compounding time of PN.