Effects of timing of enteral nutrition in the severe acute pancreatitis

Objective To explore the effects of timing of enteral nutrition (EN) in the severe acute pancreatitis (SAP) . Methods The rabbit model of SAP was constructed, and 40 experimental rabbits were divided randomly into the experimental group (20 rabbits) and the control group(20 rabbits) . (1) The parenteral nutrition (PN) was administered to rabbits in the experimental group, and then EN was administered after bowel sound restoration. (2) EN was administered to the rabbits in the control group at hour 12 after PN. The values of TNF-α , IL-6 and IL-8 on post-modeling day 1, 3 and 7 and intra-abdominal pressures at hour 1 before EN and on post-modeling day 1 and 3 were respectively examined. The experimental animals were sacrificed on post-modeling day 7 and 10. The expression of nuclear factor-kappa B (NF-κB) was detected by immunohistochemistry and bacteria from mesenteric lymph nodes were cultured. The measurement data with normal distribution were presented as ±s. The trend comparison between groups and pairwise comparison were analyzed using the repeated measures ANOVA andt test. Results The 40 rabbit models of SAP were constructed successfully. (1) The results of serum test showed that the values of TNF-α , IL-6 and IL-8 in the experimental group on post-modeling day 1, 3 and 7 were (6. 9 ±2.1) ng/ L, (5.9 ± 1.8) ng/ L, (5.3 ± 1.8) ng/ L and (109 ± 17) ng/ L, (96 ± 16) ng/ L, (83 ±17) ng/ L and (89 ±20) ng/ L, (78 ±21) ng/ L, (70 ±19) ng/ L, respectively. The values of TNF-α, IL-6 and IL-8 in the control group on post-modeling day 1, 3 and 7 were (7. 4 ±1.5) ng/ L , (7.1 ±1. 6) ng/ L (6.8 ± 1. 7) ng/ L and (101 ±19) ng/ L , (98 ±18) ng/ L , (93 ±20) ng/ L and (91 ±14) ng/ L , (91 ±16) ng/ L , (83 ± 19) ng/ L, respectively. There were significant differences in the changing trends of TNF-α and IL-6 between the 2 groups (F =7.947, 19.386, P 0.05) . (2) The intra-abdominal pressures in the experimental group at hour 1 before EEN and on post-modeling day 1 and 3 were (3. 5 ±1. 6) cmH2O (1 cmH2O =0.098 kPa) , (4. 3 ±1. 7) cmH2O and (3. 6 ±1. 8) cmH2O, which were significantly different from (4.9 ± 1. 9) cmH2O, (5.7 ± 2. 2 ) cmH2O and (4. 5 ±1. 6) cmH2O in the control group (F =7.042, P <0.05) . (3) The expression of NF-κB in the tissues of pancreas was localized mainly in the cell nucleus. The expression of NF-κB in the experimental group on post-modeling day 7 was 5. 0 ±2.7, which was significantly different from 7.0 ±2.9 in the control group (t =2.236, P <0.05) . (4) The amount of bacteria culture from mesenteric lymph nodes in the experimental group on post-modeling day 7 and 10 were (4.7 ± 0.9) × 103 cfu/ g and (4.1 ± 0.7) × 103 cfu/ g, which were significantly different from (5. 5 ±1. 0) ×103 cfu/ g and (4. 6 ±0. 7) × 103 cfu/ g in the control group (t =2.382, 2.126, P < 0.05) . Conclusion The selective timing of EN can effectively improve the recovery of rabbits with SAP, and the efficacy of EN administering based on the recovery of bowel function may be better than immediate EN administering. Key words: Severe acute pancreatitis; Nutritional support therapy, enteral; Inflammatory factor; Nuclear factor-kappa B