Gastric emptying of three liquid oral preoperative metabolic preconditioning regimens measured by magnetic resonance imaging in healthy adult volunteers: a randomised double-blind, crossover study.
OBJECTIVE
Preoperative starvation has many undesirable effects but the minimum length of fasting is limited by gastric emptying, which may be dependent on nutrient content, viscosity and osmolarity of the feed. We compared the gastric emptying of two types of preoperative metabolic preconditioning drinks [Oral Nutritional Supplement (ONS) (Fresenius Kabi, Germany) and preOp (Nutricia Clinical Care, UK)] in healthy volunteers.


METHODS
Twenty (10 male, 10 female) healthy adult volunteers were studied on 3 separate occasions in a randomised crossover manner. Volunteers ingested 400 ml preOp, which is a clear carbohydrate drink (CCD) (50 g carbohydrate, 0 g protein), 70 g ONS (50 g carbohydrate and 15 g glutamine) dissolved in water to a total volume of 400 ml (ONS400) and 300 ml (ONS300). Gastric emptying time was measured using magnetic resonance imaging.


RESULTS
Mean (95% CI) T(50) and T(100) gastric emptying times for CCD were significantly lower (p<0.001) compared with ONS400 and ONS300. T(50) was 47 (39-55), 78 (69-87) and 81 (70-92)min for CCD, ONS400 and ONS300 respectively. Correspondingly T(100) was 94 (79-110), 156 (138-173) and 162 (140-184)min. Residual gastric volumes returned to baseline 120 min after CCD and 180 min after ONS400 and ONS300.


CONCLUSIONS
The faster gastric emptying for CCD compared to ONS400 and ONS300 signifies that gastric emptying may be more dependent on nutrient load than volume or viscosity in healthy volunteers. While it is safe to give CCD 2h preoperatively, ONS400 and ONS300 should be given at least 3h preoperatively.
Lobo
Dileep N
DN
Division of Gastrointestinal Surgery, Nottingham Digestive Diseases Centre Biomedical Research Unit, Nottingham University Hospitals, Queen's Medical Centre, Nottingham, UK. dileep.lobo@nottingham.ac.uk
Hendry
Paul O
PO
Rodrigues
Gabriel
G
Marciani
Luca
L
Totman
John J
JJ
Wright
Jeff W
JW
Preston
Tom
T
Gowland
Penny
P
Spiller
Robin C
RC
Fearon
Kenneth C H
KC
D000293:Adolescent; D000328:Adult; D018592:Cross-Over Studies; D003681:Dehydration / Q000517:prevention & control; D019587:Dietary Supplements / Q000706:statistics & numerical data; D004311:Double-Blind Method; D005260:Female; D005746:Gastric Emptying; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care / Q000379:methods*; D012727:Sex Characteristics; D013997:Time Factors; D055815:Young Adult