Effects of Glutamine on Gastric Emptying
Condition: Starvation
MeSH terms: Starvation
Study type: Interventional
Phase: Phase 4

Summary: 
      Surgical patients are usually starved for 8 hours before operation in order to ensure the
      stomach is empty and thus reduce the chances of vomiting during the anaesthetic. Recent
      studies have shown that this period of starvation is harmful as it 'weakens' the body before
      operation. To avoid the harmful effects of starvation, patients are now given carbohydrate
      (sugar-containing) drinks 2 to 4 hours before surgery. These drinks have been shown to make
      patients feel better, reduce sickness after the anaesthetic/surgery and result in a quicker
      recovery from operation. The optimum time of giving these drinks to patients before operation
      is unknown. Previous studies have shown that the drinks empty from the stomach within 2 - 4
      hours depending on their ingredients. The investigators would like to study the effects of
      adding protein and fat to these drinks on how quickly the drinks empty from the stomach. This
      study will investigate the hormone responses of the body following intake of 3 different
      drinks in order to determine the mechanisms that underlie the control of stomach emptying.
      This information will also allow us to improve the design of these drinks and this could help
      patients who undergo surgery who receive them.
    

Detailed description: 
      The eligibility criteria for this study are as follows:

      Interested participants will be asked to attend a screening interview during which the study
      procedures/risks/benefits will be explained, followed by a brief history and physical
      examination. If deemed necessary by the study investigator, a 7ml sample of blood will be
      taken for screening purposes. The volunteer will be deemed eligible for the study once they
      have passed the screening visit and [when performed] had normal screening blood investigation
      results.

      Each volunteer will be studied 3 times, the order of which will be determined randomly by
      computer. Participants will report for the study at the Division of GI Surgery (E-floor, West
      Block, Queen's Medical Centre), at 7:15am. On arrival the subject's height and weight will be
      recorded and 'drip needle' will will be placed in the back of the wrist. The hand will be
      rested in a hand-heater allowing venous blood to be sampled.

      The subject will be randomly allocated to receive one of the three study drinks. At 7:50am
      baseline blood will be sampled (10ml [1.5 tablespoons] via the drip needle). At 8am the
      volunteers will drink the study drink. The rate of stomach emptying will be measured by using
      Gamma scintigraphy (a specialised medical camera). The drinks will have added a tracer
      substance that is visible on the camera and allows us to follow drink as it passes through
      the stomach into the bowels. Each 'picture' of the stomach lasts 20 seconds and we plan to
      take these every 20 minutes for 4 hours after intake of the drink. At 20 minute intervals
      (until 220 mins have elapsed) 7ml (1 tablespoon) of blood will be sampled via the drip
      needle. The final 10 ml blood sample will be taken at 240 minutes following which the drip
      needle will be removed and the volunteers will be allowed home. The subsequent two studies
      will be performed 7 days following the first study.

      In total 95ml (a sixth of a pint) blood will be taken during each of the 3 crossover studies
      which will be separated by a period of 7 days (i.e. a total of 285 ml [half a pint] blood
      will be required from each volunteer).
    

Intervention name(s): Nutricia PreOp nutritional supplement; Lipid; Glutamine
Intervention type(s): Dietary Supplement; Dietary Supplement; Dietary Supplement
Intervention description(s): nutritional supplement; Drink; Drink
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Single (Investigator)
Primary purpose: Basic Science
Keywords: Dietary supplement; Carbohydrate loading; Healthy volunteers; Anaesthesia; Surgery; Glutamine