AUTHOR=Ozolina Agnese , Nemme Janis , Ozolins Arturs , Bjertnæs Lars J. , Vanags Indulis , Gardovskis Janis , Viksna Ludmila , Krumina Angelika 

TITLE=Fibrinolytic System Changes in Liver Surgery: A Pilot Observational Study

JOURNAL=Frontiers in Medicine

VOLUME=Volume 5 - 2018

YEAR=2018

URL=https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2018.00253

DOI=10.3389/fmed.2018.00253

ISSN=2296-858X

ABSTRACT=Introduction: Bleeding is a complication of liver surgery. Unbalance between tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) might increase bleeding. Our aim was to analyze perioperative fibrinolytic changes during liver surgery.

Materials and Methods: We evaluated 15 patients for inclusion into a prospective pilot study of liver surgery. We assessed fibrinolysis by plasma PAI-1 and t-PA:  before surgery (T1), before Pringle maneuver (T2), at the end of surgery (T3), 24 hours postoperatively (T4), and registered demographic, laboratory data, extent and duration of surgery, hemodynamic parameters, blood loss, transfused volumes of blood products. Data presented as mean ± SD. Significance at P<0.05. 

Results: After exclusion of six patients, who underwent biopsies, we included six women and three men aged 49.1 ± 19.6 years; two patients with liver metastases of colorectal cancer and hepatocellular carcinoma, two with focal nodular hyperplasia, two with hepatic hemangioma and one with angiomyolipoma. Six patients underwent the Pringle maneuver. PAI-1 plasma concentration (n=9) rose from 6.25 ± 2.25 at T1 through 17.30 ± 14.59 ng/ml at T2 and 28.74 ± 20.4 (p=0.007) and 22.5 ± 16.0 ng/ml (p=0.04), respectively, at T3 and T4. Correspondingly, t-PA plasma concentration (n=9) increased from 4.76 ± 3.08 ng/ml at T1 through 8.00 ± 5.10 ng/ml (p = 0.012) at T2 and decreased to 4.25 ± 2.29 ng/ml and 3.04 ± 3.09 at T3 and T4, respectively. Plasma t-PA level at T2 was significantly different from those at T1, T3 and T4 (p<0.004). In Pringle maneuver patients, plasma t-PA levels increased from T1, peaked at T2 (p=0.001), subsequently decreased at T3 and T4 (p=0.011 and p = 0.037), respectively. 
Mean blood loss was 1377.7 ± 1062.8 ml. Seven patients received blood products. Patients with higher PAI-1 levels at T3 received more fresh frozen plasma (r = 0.79; p=0.01) and red blood cells (r = 0.88; p=0.002). 
Conclusions: During liver surgery, fibrinolysis increased, as evidenced by rises in plasma PAI-1and t-PA, especially after start of surgery and following the Pringle maneuver. Transfused volumes of blood products correlated with higher plasma concentrations of PAI-1.Confirming this tendency requires a larger cohort of patients.