ABSTRACT
Background: To
investigate the changes in plasma levels of endothelin (ET), nitric oxide (NO),
prostacyclin (PGI2) and thromboxane A2 (TXA2)
in patients undergoing abdominal operation. Materials and Methods: Thirty cases
of abdominal surgery (14 males, 16 females; mean age 48 ± 11 years, ranging
from 24 to 70) were prospectively recruited: Twenty-four cases of
cholelithiasis and cholecystitis, 2 cases of peptic ulcer and 4 cases of portal
vein hypertension. At five different time points (1-3 days after
hospitalization (T1), at surgery beginning, after anesthesia (T2) and at the
first (T3), third (T4) and fifth day (T5) after surgery), plasma levels of
ET-1, NO2-, NO3-, 6-keto-PGF1α and thromboxane B2 (TXB2), the latter
two being stable metabolites of PGI2 and TXA2 respectively, were measured. Results: ET-1 levels increased significantly after
anesthesia and surgery (T1 = 69.2 ± 10.7 vs. T2 = 82.4 ± 14.7 vs. T3 = 96.6 ± 22.8
pg/ml, p < 0.05). TXB2 levels before surgery were significantly
lower than that after (T2 = 67.5 ± 52.7 vs. T3 = 157.6 ± 21.8 pg/ml, p < 0.05).
Pre-surgery NO levels were significantly higher than that after surgery (T1 = 2575
± 50 vs. T2 = 1922 ± 44 vs. T3 = 1692 ± 39 ng/ml, p < 0.05 for T1 vs. T2 and
T3). Pre-surgery levels of 6-keto-PGI1α were significantly higher than that after anesthesia and surgery (T1 = 180.5 ± 17.8
vs. T2 = 132.1 ± 32.6 vs. T3 = 110.9 ± 31.9 pg/ml, p < 0.05 for T1 vs. T2
and T3). Conclusions: Level of vasoconstrictive factors (ET and TXA2)
increased significantly after surgery, while vasodilatory factors (NO and PGI2)
decreased significantly after operation. Imbalance in vasoactive factors encourages
hypercoagulability and then may play a role in the pathobiology of post-surgery
complications, such as deep venous thrombosis (DVT).