European Society of Anaesthesiology.

BackgroundObesity is known as a major risk factor for postoperative vein thrombosis. Thromboelastography (TEG) is used to monitor viscoelastic features of blood clots. The aim of this study was to determine hypercoagulable states in patients undergoing bariatric surgery and to assess dynamics of coagulation parameters in the perioperative setting using TEG.Material/MethodsWe included 60 consecutive patients undergoing bariatric surgery. TEG alterations were assessed at 4 time points: at baseline, after the surgery, and on postoperative day 1 (POD1) and 2 (POD2). Hypercoagulable state was defined when patients showed clot strength (G) of ≥11 dynes/cm2 or maximum amplitude (MA) ≥68 mm.ResultsFourteen patients (23.3%) out of 60 showed hypercoagulability prior to surgery on TEG. Fibrinogen levels were significantly higher in the G ≥11 group compared to the G <11 group, at 4.2 and 3.8 g/l, respectively (p=0.02). Seventeen patients (28.3%) had MA ≥68 mm at baseline. Fibrinogen levels increased significantly from 3.90 at baseline to 4.16 g/l in POD2 (p<0.001). There was an increase in mean reaction time from baseline (6.74 s) to POD2 (7.43 s, p=0.022). We found a correlation between baseline fibrinogen levels and MA (R=0.431, p=0.001) or G (R=0.387, p=0.003). ROC curve analysis showed that fibrinogen levels can predict clot strength (G) ≥11 dynes/cm2 with AUC=0.680 (p=0.044).ConclusionsA considerable proportion of patients referred to bariatric surgery show a trend towards hypercoagulability on TEG. This study shows the potential of hypercoagulation monitoring by TEG in the perioperative setting of bariatric surgery.

No abstract

Background and objective. Hepatic hypoperfusion is regarded as an important factor in the pathophysiology of perioperative liver injury. Although thoracic epidural anesthesia is a widely used technique, limited data are available about the effects on hepatic blood flow with blockade restricted to thoracic segments in humans. The main objective of the present study was to investigate the effects of thoracic epidural anesthesia on hepatic blood flow under general anesthesia in humans. Material and methods. In 40 patients under general anesthesia, we assessed hepatic blood flow using plasma disappearance rate of indocyanine green (PDRICG) as a simple noninvasive method before and after induction of thoracic epidural anesthesia. The epidural catheter was inserted at the Th7/8 or Th8/9, and 1% lidocaine at a mean (range) dose of 8 (6–10) mL was injected. Ephedrine bolus was given to patients who demonstrated a decrease in mean arterial blood pressure below 60 mm Hg after induction of thoracic epidural anesthesia (TEA-E group). Other patients did not receive any catecholamines during the study period (TEA group). Ten patients who did not undergo TEA served as controls (control group). Results. In 7 patients, administration of ephedrine was necessary to avoid a decrease in mean arterial blood pressure below 60 mm Hg. Thus, the TEA-E group consisted of 7 patients and TEA group of 33. In the TEA group, thoracic epidural anesthesia was associated with a mean 2.3% min–1 decrease in PDRICG (P<0.05). In the TEA-E group, all seven patients showed a 2.2% min–1decrease in PDRICG (P<0.05). Patients in the control group showed a mean 1.1% min–1 increase in PDRICG (P<0.05). In contrast to hepatic blood flow, cardiac output was not affected by thoracic epidural anesthesia. Conclusions. In humans, thoracic epidural anesthesia is associated with a decrease in hepatic blood flow. Thoracic epidural anesthesia combined with ephedrine bolus was found to result in further decrease in hepatic blood flow.

Objective. Obesity is a well-known risk factor for thrombotic complications. The aim of the present study was to determine the frequency of thrombosis related ABO, F5, MTHFR, and FGG gene polymorphisms in morbidly obese patients and compare them with the group of nonobese individuals. Methods. Gene polymorphisms were analyzed in 320 morbidly obese patients (BMI > 40 kg/m2) and 303 control individuals (BMI < 30 kg/m2) of European descent. ABO C>T (rs505922), F5 C>G (rs6427196), MTHFR C>T (rs1801133), and FGG C>T (rs6536024) SNPs were genotyped by RT-PCR. Results. We observed a tendency for MTHFR rs1801133 TT genotype to be linked with morbid obesity when compared to CC genotype; however, the difference did not reach the significant P value (OR 1.84, 95% CI 0.83–4.05, P = 0.129). Overall, the genotypes and alleles of rs505922, rs6427196, rs1801133, and rs6536024 SNPs had similar distribution between morbidly obese and nonobese control individuals. Distribution of height and weight means among individuals carrying different rs505922, rs6427196, rs1801133, and rs6536024 genotypes did not differ significantly. Conclusions. Gene polymorphisms ABO C>T (rs505922), F5 C>G (rs6427196), MTHFR C>T (rs1801133), and FGG C>T (rs6536024) were not associated with height, weight, or morbid obesity among European subjects.