The Effect of Sequential Feeding for Circadian Rhythm and Gut Flora Rhythm in Critically Ill Patients

Study Overview
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Brief Summary
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Circadian rhythms plays an important role for healthy. And critical illness contributes to the disruption of circadian rhythms. Not only right but also feeding can affect the circadian clock gene expression. In a investigators' previous study, some metabolic indicators (the albumin level, total cholesterol level and total bile acid level) and the increases in lymphocyte counts in the sequential feeding group were different from those in the continuous feeding group. Investigators think sequential feeding may adjust circadian clock gene expression for its effect on metabolism and immunity. Moreover, sequential feeding did alter the abundances of some gut microbes to some degree in the investigators' previous study. Investigators think sequential feeding may adjust gut flora rhythms.

Official Title
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The Effect of Sequential Feeding for Circadian Rhythm and Gut Flora Rhythm in Critically Ill Patients

Conditions
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Feeding Patterns, Critical Illness, Circadian Rhythm Disorders

Intervention / Treatment
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* Other: feeding type


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients newly admitted to ICU were eligible for inclusion. Exclusion Criteria: An estimated feeding time of less than 10 days in ICU; Diabetes; Gastrointestinal disease (gastrointestinal surgery, gastrointestinal bleeding, pancreatitis, Crohn's disease, ulcerative colitis, irritable bowel syndrome); Inability to tolerate ≥80% of the nutrition target calories (25-30 kcal/kg/d) with enteral feeding through gastric tube; The ability to eat orally at admission.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sequential feeding group<br>After achieving ≥80% of the nutrition target calories (25-30 kcal/kg/d) by continuous feeding, continuous feeding was changed into intermittent feeding. The total daily dosage of enteral nutrition was equally distributed during three periods at 7-9:00, 11-13:00 and 17-19:00. The enteral nutritional suspension administered during each period was given at a uniform rate within two hours by an enteral feeding pump. The other times of the day were fasting times. | Other: feeding type<br>* In our department, the ICU patients received continuous feeding or sequential feeding. Patients received continuous feeding with a constant velocity by an enteral feeding pump over one day. In sequential feeding type, after achieving ≥80% of the nutrition target calories (25-30 kcal/kg/d), the patients received intermittent feeding. The total daily dosage of enteral nutrition was equally distributed during three periods at 7-9:00, 11-13:00 and 17-19:00. The enteral nutritional suspension administered during each period was given at a uniform rate within two hours by an enteral feeding pump. The other times of the day were fasting times.<br>|
| Continuous feeding group<br>Patients received continous feeding with a constant velocity by an enteral feeding pump over one day. | Other: feeding type<br>* In our department, the ICU patients received continuous feeding or sequential feeding. Patients received continuous feeding with a constant velocity by an enteral feeding pump over one day. In sequential feeding type, after achieving ≥80% of the nutrition target calories (25-30 kcal/kg/d), the patients received intermittent feeding. The total daily dosage of enteral nutrition was equally distributed during three periods at 7-9:00, 11-13:00 and 17-19:00. The enteral nutritional suspension administered during each period was given at a uniform rate within two hours by an enteral feeding pump. The other times of the day were fasting times.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| clock genes expression | Genes including BMAL1 CLOCK TIMELESS PER1 and so on | 7 days feeding | 
| Gut Flora Rhythm | α diversity including shannon index and so on | 7 days feeding |