Coagulopathy following major liver resection: the effect of rBPI21 and the role of decreased synthesis of regulating proteins by the liver

Does clamping during liver surgery predispose to thrombosis of the hepatic veins? Analysis of 210 cases

AIM: To test whether clamping during liver surgery predisposes to hepatic vein thrombosis.

METHODS: We performed a retrospective analysis of 210 patients who underwent liver resection with simultaneous inflow and outflow occlusion. Intraoperatively, flow in the hepatic veins was assessed by Doppler ultrasonography during the reperfusion phase. Postoperatively, patency of the hepatic veins was assessed by contrast-enhanced CT angiography, when necessary after 3-6 mo follow up.

RESULTS: Twelve patients (5.7%) developed intraoperative liver remnant swelling. However, intraoperative ultrasonography did not reveal evidence of hepatic vein thrombosis. In three of these patients a kinking of the common trunk of the middle and left hepatic veins hindering outflow was recognized and was managed successfully by suturing the liver remnant to the diaphragm. Twenty three patients (10.9%) who developed signs of mild outflow obstruction postoperatively, had no evidence of thrombi in the hepatic veins or flow disturbances on ultrasonography and contrast-enhanced CT angiography, while hospitalized. Long term assessment of the patency of the hepatic veins over a 3-6 mo follow-up period did not reveal thrombi formation or clinical manifestations of outflow obstruction.

CONCLUSION: Extrahepatic dissection and clamping of the hepatic veins does not predispose to clinically important thrombosis.

[Significance of liver trauma for the incidence of sepsis, multiple organ failure and lethality of severely injured patients. An organ-specific evaluation of 24,771 patients from the trauma register of the DGU]

BACKGROUND

The prognosis of multiple injured patients is mainly limited by initial severe hemorrhage causing hemorrhagic shock, subsequent sepsis and multiple organ failure (MOF). Although mechanisms of altered microcirculation, cytokine release etc. have been intensively investigated, little is known about the relevance of severe liver trauma as an independent predictive outcome factor in these patients. This study aimed to clarify the impact of severe liver trauma in one of the largest trauma databases.

PATIENTS AND METHODS

The study was based on data from the German trauma register within the German Society for Trauma Surgery (DGU) and 24,711 patients from 113 hospitals were collected for retrospective analysis between 1993 and 2005. Patients with an injury severity score (ISS) >16, no isolated head injury and primary admission to a trauma center were included. Data were allocated according to the injury pattern into I liver group (severe damage of the liver, AIS>3 and AIS abdomen <3), II Abdomen group (severe abdominal trauma AIS>3, AIS liver <3) and III Control group (liver and/or abdominal trauma AIS<3, other trauma AIS>3).

RESULTS

Out of 24,771 multiple injured patients from 113 trauma centers, 321 individuals were identified which matched the criteria of the liver group. Another 574 patients were allocated to the abdomen group while the majority of patients formed the trauma group (9574). Severe injury of the liver is associated with excessive demands for volume resuscitation and induces a significantly increased risk for sepsis and MOF compared to both other groups (sepsis 19.9% vs 11%; MOF 32.7% vs 16.6%). Furthermore, deleterious outcome is more frequent associated with patients with severe liver trauma (lethality 34.9%) compared to severe abdominal trauma (12%) and the control group (19.5%).

CONCLUSIONS

Severe liver trauma is an independent predictor for severe hemorrhage with a substantial increased risk of sepsis, MOF and trauma-related death. While conservative treatment of patients with severe liver trauma but no hemorrhage is effective, patients with hemodynamic instability seem to form a subgroup where contemporary treatment modalities are not yet sufficient.

Preoperative methylprednisolone administration maintains coagulation homeostasis in patients undergoing liver resection: importance of inflammatory cytokine modulation

Alterations in hemostatic parameters are a common finding after major hepatic resection. There is growing evidence that inflammation has a significant role in inducing coagulation disarrangement that follows major surgery. To determine whether preoperative methylprednisolone administration has a protective effect against the development of coagulation disorders, we evaluated the effect of preoperative steroids administration on changes in hemostatic parameters and plasma levels of inflammatory cytokines in patients undergoing liver surgery. Seventy-three patients undergoing liver resection were randomized to a steroid group or to a control group. Patients in the steroid group received 500 mg of methylprednisolone preoperatively. Serum levels of coagulation parameters (prothrombin time, platelets, fibrinogen, plasma fibrin degradation products [D-dimer], antithrombin III) and inflammatory mediators (IL-6 and TNF-alpha) were measured before and immediately after the operation and on postoperative days 1, 2, and 5. Multivariate analysis was performed to identify factors related to the characteristics of the patients and surgery affecting coagulation parameters between the two groups. Decreases in antithrombin III, platelet count and fibrinogen levels, prolongation of prothrombin time, and increases in the plasma fibrin degradation products were significantly suppressed by the administration of methylprednisolone. Cytokines production was also significantly suppressed by the administration of methylprednisolone, and there was significant correlation between plasma levels of cytokines and coagulation alterations. These findings suggest that preoperative methylprednisolone administration inhibits the development of coagulation disarrangements in patients undergoing liver resection, possibly through suppressing the production of inflammatory cytokines.

New insights into the coagulopathy of liver disease and liver transplantation

The liver is an essential player in the pathway of coagulation in both primary and secondary haemostasis. Only von Willebrand factor is not synthetised by the liver, thus liver failure is associated with impairment of coagulation. However, recently it has been shown that the delicate balance between pro and antithrombotic factors synthetised by the liver might be reset to a lower level in patients with chronic liver disease. Therefore, these patients might not be really anticoagulated in stable condition and bleeding may be caused only when additional factors, such as infections, supervene. Portal hypertension plays an important role in coagulopathy in liver disease, reducing the number of circulating platelets, but platelet function and secretion of thrombopoietin have been also shown to be impaired in patients with liver disease. Vitamin K deficiency may coexist, so that abnormal clotting factors are produced due to lack of gamma carboxylation. Moreover during liver failure, there is a reduced capacity to clear activated haemostatic proteins and protein inhibitor complexes from the circulation. Usually therapy for coagulation disorders in liver disease is needed only during bleeding or before invasive procedures. When end stage liver disease occurs, liver transplantation is the only treatment available, which can restore normal haemostasis, and correct genetic clotting defects, such as haemophilia or factor V Leiden mutation. During liver transplantation haemorrage may occur due to the pre-existing hypocoagulable state, the collateral circulation caused by portal hypertension and increased fibrinolysis which occurs during this surgery.

The use of intrathecal morphine for postoperative pain relief after liver resection: a comparison with epidural analgesia

An epidural catheter is used in some institutions for postoperative analgesia after liver surgery. However, anesthesiologists may not feel comfortable leaving a catheter in the epidural space because of concern about coagulation disturbances and possible bleeding complications caused by impaired liver function. In this study, we tested a single-shot intrathecal morphine technique and compared it to a continuous epidural naropine infusion for postoperative analgesia in liver surgery. Fifty patients were randomly assigned to an epidural analgesia group (EP group; n = 25) and an intrathecal analgesia group (IN group; n = 25). The quality of analgesia assessed by a visual analog scale (VAS), the side effects, and the additional IV analgesic requirements were recorded. We did not observe any signs of cord compression. Time to first pain drug requirement was longer in the EP group compared to the IN group (25 +/- 18.5 h versus 12 +/- 10.3 h; P < 0.05). In both groups, the VAS remained less than 30 mm throughout the 48-h follow-up period. Consumption of IV morphine with a patient-controlled analgesia device in the IN group was larger (mostly from 24 to 48 h after surgery) than the EP group (12.0 +/- 5.54 mg versus 3.1 +/- 2.6 mg, respectively; P < 0.01). The incidence of vomiting was 4% in both groups, whereas the incidence of pruritus (16% versus 0%) and nausea (16% versus 4%) was more frequent in the IN group. No postdural puncture headache and no spinal hematoma occurred. After liver resection, a single dose of intrathecal morphine followed by patient-controlled morphine analgesia can provide satisfactory postoperative pain relief. The quality of this treatment, according to the VAS, is not inferior to continuous epidural analgesia up to 48 h after surgery.

Increased prothrombin time and platelet counts in living donor right hepatectomy: implications for epidural anesthesia

The risks and benefits of adult-to-adult living donor liver transplantation need to be carefully evaluated. Anesthetic management includes postoperative epidural pain relief; however, even patients with a normal preoperative coagulation profile may suffer transient postoperative coagulation derangement. This study explores the possible causes of postoperative coagulation derangement after donor hepatectomy and the possible implications on epidural analgesia. Thirty donors, American Society of Anesthesiology I, with no history of liver disease were considered suitable for the study. A thoracic epidural catheter was inserted before induction and removed when laboratory values were as follows: prothrombin time (PT) > 60%, activated partial thromboplastin time < 1.24 (sec), and platelet count > 100,000 mmf pound sterling (mm3). Standard blood tests were evaluated before surgery, on admission to the recovery room, and daily until postoperative day (POD) 5. The volumes of blood loss and of intraoperative fluids administered were recorded. Coagulation abnormalities observed immediately after surgery may be related mostly to blood loss and to the diluting effect of the intraoperative infused fluids, although the extent of the resection appears to be the most important factor in the extension of the PT observed from POD 1. In conclusion, significant alterations in PT and platelet values were observed in our patients who underwent uncomplicated major liver resection for living donor liver transplantation. Because the potential benefits of epidural analgesia for liver resection are undefined according to available data, additional prospective randomized studies comparing the effectiveness and safety of intravenous versus epidural analgesia in this patient population should be performed.

KUPFFER CELL???DEPLETED RATS HAVE A DIMINISHED ACUTE-PHASE RESPONSE FOLLOWING MAJOR LIVER RESECTION

Partial hepatectomy (PH)-induced Kupffer cell (KC) activation results in a rapid release of cytokines inducing the acute-phase response (APR). This study was done to evaluate the role of Kupffer cells (KCs) in the course of the APR following PH and a consecutive endotoxin challenge. KC depletion was performed in rats by i.v. administration of 1 mL liposome-encapsulated dichloromethylene diphosohonate (Cl2MDP). Control rats received 1 mL NaCl 0.9%. Forty-eight hours later, PH was performed. At 24 h after PH, rats were randomized to receive either 1 mL NaCl 0.9% (saline) or 50 microg/kg LPS i.v. in 1 mL. Animals were sacrificed at 4 h after LPS or saline infusion. The APR was determined by measuring hepatic gene expression of alpha 2-macroglobulin, alpha 1-acid glycoprotein, and IL-6 and expression of hepatic albumin. The APR was significantly depressed in KC-depleted rats. Despite increased IL-6 mRNA synthesis in response to low-dose LPS, no enhancement of acute-phase protein synthesis (APP) was found in KC-depleted rats. Hepatic failure was most profound in KC-depleted rats, as indicated by elevated plasma levels of liver transaminases and ammonia. We conclude that after PH, KC function in the remnant liver is important for the acute-phase reaction and reduces endotoxin-induced hepatocyte damage.

Altered hematologic profiles following donor right hepatectomy and implications for perioperative analgesic management

Living liver donors for adult liver transplant recipients undergo extensive liver resection. Partial donor hepatectomies may alter postoperative drug metabolism and hemostasis; thus, the risks and the benefits of pain management for this unique patient population may need to be reassessed. The safety and efficacy of combined epidural analgesia and field infiltration in our initial living liver donor group are presented. A thoracic epidural catheter was placed before general anesthesia in 2 female and 6 male donors (44.2 +/- 11.3 years old, mean +/- standard deviation [SD], range 26-56). At the end of surgery, incisions were infiltrated (bupivacaine 0.25%), and an epidural infusion was used (bupivacaine 0.1% + hydromorphone hydrochloride 0.02%). Clinical outcomes were followed for 5 days. The time sequence of pain intensity on a 0-10 visual analog scale clustered into 3 phases, the intensity of which differed significantly from each other (2.2 +/- 0.6, 0.69 +/- 0.2, and 2.37 +/- 0.3 respectively, P = 0.028). Right shoulder pain was observed in 75% of the donors. Sedation, pruritus, and nausea were minimal. Consistently maximal international normalized ratio elevation occurred at 17.6 +/- 7 hours postoperatively, then slowly declined. Platelet counts were lowest on day 3. No neurologic injury or local anesthetic toxicity was observed. This 2-site approach provided effective, safe, postoperative analgesia for our donors. Universally, coagulopathy ensued, indicating a potentially increased risk for epidural hemorrhage at epidural catheter removal and mandating close postoperative neurologic and laboratory monitoring. Research is needed to advance the understanding of postoperative coagulopathy and hepatic dysfunction in these donors to further optimize their perioperative management, including that of analgesia.

Antithrombin III inhibits nuclear factor kappaB activation in human monocytes and vascular endothelial cells

The serpin antithrombin III (AT III), the most important natural inhibitor of thrombin activity, has been shown to exert marked anti-inflammatory properties and proven to be efficacious in experimental models of sepsis, septic shock, and disseminated intravascular coagulation. Moreover, clinical observations suggest a possible therapeutic role for AT III in septic disorders. The molecular mechanism, however, by which AT III attenuates inflammatory events is not yet entirely understood. We show here that AT III potently blocks the activation of nuclear factor kappaB (NF-kappaB), a transcription factor involved in immediate early gene activation during inflammation. AT III inhibited agonist-induced DNA binding of NF-kappaB in cultured human monocytes and endothelial cells in a dose-dependent manner, suggesting that AT III interferes with signal transduction leading to NF-kappaB activation. This idea was supported by demonstrating that AT III prevents the phosphorylation and proteolytic degradation of the inhibitor protein IkappaBalpha. In parallel to reducing NF-kappaB activity, AT III inhibited the expression of interleukin-6, tumor necrosis factor-alpha, and tissue factor, genes known to be under the control of NF-kappaB. The observation that chemically modified AT III that lacks heparin-binding capacity had no effect on NF-kappaB activation supports the current understanding that the inhibitory potency of AT III depends on the interaction of AT III with heparinlike cell surface glycosaminoglycans. This hypothesis was underscored by the finding that the AT III beta-isoform, known to have higher affinity for glycosaminoglycans, is more effective in preventing NF-kappaB transactivation than alpha-AT III. These data indicate that AT III can alter inflammatory processes via inhibition of NF-kappaB activation.

Minimally invasive hepatectomy: modulation of systemic reactions to operation or laparoscopic approach?

BACKGROUND

A new concept of surgical stress has been proposed that consists of both aggressiveness of operation and systemic reactions to an operation.

METHODS AND RESULTS

We have investigated a possible modulation of such systemic reactions to operation and have demonstrated the following 3 points: (1) coagulation and fibrinolytic systems are independently activated during hepatectomy and such activation can be modulated by protease inhibitors such as nafamostat mesilate and antithrombin III; (2) elevated thromboxane A2 during hepatectomy is characterized in the prostanoid system, the elevation of thromboxane A2 is inhibited by thromboxane A2 synthetase inhibitor, and postoperative liver injury is reduced; (3) cytokine response induced by hepatectomy is modulated by preoperative administration of methylprednisolone, leading to possible prevention of bacterial translocation. Therefore, modulating systemic reactions to hepatectomy may be important for successful minimally invasive hepatectomy. Another important option for minimally invasive hepatectomy is the use of operative procedures such as laparoscope or thoracoscope. We have investigated the usefulness of a laparoscopic hepatectomy from the standpoints of early and long-term outcome after hepatectomy. Laparoscopic hepatectomy, which is a difficult and dangerous procedure, can be a feasible option and can result in better short-term outcome and a similar long-term outcome after hepatectomy when compared with conventional open hepatectomy. Therefore, the laparoscopic approach is also a viable option for minimally invasive hepatectomy.

CONCLUSIONS

Modulation of systemic reactions to the operation itself and laparoscopic hepatectomy may be new strategies for performing minimally invasive hepatectomy.