Is total parenteral nutrition protective against hypoglycemia during intensive insulin therapy? A hypothesis

It appears that enteral nutrition is more likely to produce hypoglycemia during intensive insulin therapy than is total parenteral nutrition.

Although this consequence may in part be the result of frequent discontinuation of feeding or to variability of gastrointestinal absorption of nutrients, there are also distinct physiological differences between total parenteral nutrition and enteral nutrition that are more likely to be responsible, including much higher serum insulin responses to total parenteral nutrition than with enteral nutrition that approach submaximal response levels and direct appearance of administered glucose into the systemic circulation with total parenteral nutrition at rates that approximate usual postabsorptive rates and that avoid first-pass hepatic clearance.

These factors may make total parenteral nutrition more efficacious, at least initially, with intensive insulin therapy and may justify setting a higher limit for glucose control when enteral feeding is principally used.