Ten studies (n=1,264) were included: eight randomised controlled trials (RCTs; n=1,022), one observational study (n=62) and one retrospective study (n=180).
Studies in which all patients underwent pancreatic resection. TPN was associated with a higher mortality (based on two RCTs): the increase was not statistically significant in one study (6.7% versus 1.8% in the control group) and statistical significance was not reported in the other (5.9% versus 1.4% for EN and 2.8% for I-EN). TPN was associated with significantly higher overall morbidity compared with no nutritional support (45% versus 22.8%, p=0.02) in one RCT and with EN and I-EN (58.8% versus 43.5% and 33.8%, p=0.005) in another RCT. TPN was associated with a longer hospital stay compared with no TPN (mean stay 16 versus 14 days; one RCT) and EN or I-EN (18.8 versus 17.0 or 15.1 mean days, p<0.02; one RCT).
EN was associated with an increased rate of overall morbidity compared with no nutritional supplementation in one observational study (43.3% versus 28.1%, p not reported), but was associated with a lower morbidity rate in one retrospective study (65.3% versus 92.7%, p not reported). EN was associated with a shorter duration of hospital stay (13.9 versus 14.8 mean days, statistical significance not reported) compared with the control.
Studies in patients undergoing resection of gastrointestinal cancers. None of the studies reported outcome data separately for different types of surgery.
Cyclical versus non-cyclical EN.
Cyclical EN was associated with significantly fewer mean days to resumption of normal diet (12.2 versus 15.7, p=0.04) compared with continuous EN (one RCT, n=57), but there was no significant difference between treatments in the number of days of nasogastric intubation (p=0.82).