Time Course for the Changes of Serum Lipoproteins and Apolipoprotein T Concentrations after Major Surgical Trauma in Man

Trauma induces changes in the serum lipoprotein pattern in man. A characteristic apolipoprotein, named apolipoprotein T existing in its isoforms T-I to T-IV, in the high density lipoprotein (HDL) fraction of serum, also appears in response to trauma. In this report eight patients operated on for abdominal aortic aneurysms were studied concerning the time dependency in changes of serum lipoproteins and the appearance of apolipoprotein T. Blood samples for lipoprotein analysis were taken preoperatively, postoperatively on days 1, 2, 4, 6 and thereafter twice a week until discharge from the hospital. The serum lipoprotein concentrations were compared with those from a group of healthy men. The most striking abnormalities were found in serum VLDL where both concentrations of triglycerides and cholesterol decreased during the first 2 days by more than 50%, compared to the initial level, and remained low for about 1 week. Also the concentration of LDL cholesterol in serum decreased about 40% from the preoperative value during the first days. Serum HDL cholesterol either increased during the first 2 days in those patients with a low preoperative concentration or stayed on a subnormal level during the first 4 days. After day 4 the serum HDL cholesterol decreased and reached the minimum level on days 10 to 13. Already on day 1 after trauma apolipoprotein T had reached a high level in order to stay high for several weeks. The apolipoprotein T isoforms had different appearance with time and varied independently of serum cholesterol in HDL.