Fuel metabolism in a pig myocutaneous island flap model.
Unilateral denervated myocutaneous island flaps based on the superior epigastric vessels were raised in 24 pigs and the metabolic changes during the first 6 postoperative hours were monitored. Secondary to flap elevation, decreased arteriovenous (A-V) differences in oxygen, glucose, and alanine levels were observed, indicating the opening of A-V shunts and increased arterialization of the venous blood. Venous outflow increased during the first 3 hours, but the A-V differences in all metabolites were constant over the entire 6-hour observation period. Exchange of intermediary metabolites therefore increased within the first 3 hours, after which a steady state was established. The main flap fuels seemed to be fatty acids, muscle proteins, and glycogen, whereas blood-borne carbohydrates and ketone bodies played only a minor role as energy sources. Anaerobic metabolism was increased secondary to flap elevation from 2 to 6 percent as compared with preelevation values. No changes were found in concentrations of plasma catecholamines, which were constantly high. An average weight gain of 3 to 4 percent per hour was equally distributed to skin, subcutis, panniculus carnosus, and muscle. Thus the flap seemed to adapt to the new perfusion pattern within a few hours by a slightly increased anaerobic metabolism, but still with an oxidative metabolism of more than 90 percent.
Hjortdal
V E
VE
Department of Plastic and Reconstructive Surgery, University of Aarhus, Denmark.
Kjølseth
D
D
Henriksen
T B
TB
Hansen
E S
ES
Møller
N
N
D020155:3-Hydroxybutyric Acid; D000409:Alanine / Q000097:blood; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D001831:Body Temperature; D004837:Epinephrine / Q000097:blood; D005934:Glucagon / Q000097:blood; D005947:Glucose / Q000378:metabolism; D005990:Glycerol / Q000097:blood; D006885:Hydroxybutyrates / Q000097:blood; D007328:Insulin / Q000097:blood; D007773:Lactates / Q000097:blood; D009132:Muscles / Q000098:blood supply / Q000378:metabolism*; D009638:Norepinephrine / Q000097:blood; D010100:Oxygen / Q000097:blood; D012039:Regional Blood Flow; D012867:Skin / Q000098:blood supply / Q000378:metabolism*; D013524:Surgical Flaps; D013552:Swine
D001786:Blood Glucose; D006885:Hydroxybutyrates; D007328:Insulin; D007773:Lactates; D005934:Glucagon; D005947:Glucose; D000409:Alanine; D005990:Glycerol; D010100:Oxygen; D020155:3-Hydroxybutyric Acid; D009638:Norepinephrine; D004837:Epinephrine