Akio Kidokoro

Alterations in coagulation and fibrinolysis during sepsis.

Circulating levels of thrombin-antithrombin III complex (TAT) and plasmin-α2 plasmin inhibitor complex (PIC) in 49 septic patients (23 patients with organ dysfunction (OD), 26 without OD) and 11 postgastrectomy patients were measured to determine the significance of the coagulation-fibrinolytic systems in the development of OD. Tissue plasminogen activator (t-PA), plasminogen activator inhibitor 1 (PAI-1), and thrombomodulin were also measured. The mean level of TAT on the day when OD occurred was significantly higher compared with the maximum level of TAT in septic patients without OD (P < .01) or postoperative patients (P < .01). There was no difference in PIC levels between the three groups. The TAT/PIC ratio was significantly higher in septic patients with OD compared with the other groups (P < .001). Septic patients with OD showed higher levels of PAI-1 (P < .001) but not of t-PA. Thrombomodulin levels were significantly higher in the septic patients with OD compared with the others (P < .001). We conclude that suppression of the fibrinolytic system contributes to the imbalance between coagulation and fibrinolysis, and that this hypercoagulabe millieu on the endothelial surface leads to the onset of OD.

Activated protein C improves the visceral microcirculation by attenuating the leukocyte-endothelial interaction in a rat lipopolysaccharide model

Objective:Abnormalities in the vascular endothelial function play an important role in the development of septic organ dysfunction. The aim of the study was to examine the effect of recombinant human activated protein C on leukocyte-endothelial interaction in endotoxemia. Design:Experimental animal model of sepsis. Setting:University research laboratory. Subjects:Normal Wistar rats. Each animal was infused with 4.5 mg/kg lipopolysaccharide to simulate severe sepsis. Interventions:Rats were injected with endotoxin simultaneously with either a low or a high dose of recombinant human activated protein C (n = 7). One, 2, and 3 hrs after injection, mesenteric microcirculation was observed under intravital microscopy. In another series, tumor necrosis factor, interleukin-6, alanine transaminase, and blood urea nitrogen levels were evaluated (n = 5). Measurements and Main Results:The adhesive leukocyte count on the endothelium was significantly suppressed in both high-dose and low-dose groups (p < .01 and .05, respectively). The bleeding events decreased in the low-dose treatment group compared with both the control (p < .05) and high-dose group (p < .05). Microcirculatory flow as expressed by red blood cell velocity was maintained better in the low-dose group. Comparison of cytokine levels showed a significant decrease in the treatment groups. Organ damage markers were also suppressed in the treatment groups (p < .05) Conclusions:Recombinant human activated protein C demonstrated a protective effect on microcirculation through the inhibition of leukocyte-endothelial interaction and suppression of inflammatory cytokine production.

Association Between The Severity Of Sepsis And The Changes In Hemostatic Molecular Markers And Vascular Endothelial Damage Markers

It is well known that disorders of coagulation and fibrinolysis play a major role in the development of organ dysfunction during sepsis. Furthermore, the importance of the early initiation of anticoagulation therapy for severe cases has been emphasized based on the success of recent clinical trials. The purpose of this study is to search for useful markers for predicting organ dysfunction. Plasma samples were prospectively collected from 78 patients within 48 h after the onset of sepsis. Hemostatic markers and endothelial damage markers were compared between the patients with and without organ dysfunction. The WBC and platelet counts were not different between the groups. In contrast, fibrin/fibrinogen degradation products, D-dimer, thrombin-antithrombin complex, plasmin α2-antiplasmin complex, soluble fibrin, and total plasminogen activator inhibitor-1 were significantly higher, and the antithrombin activity and protein C levels were lower in the patients with organ dysfunction. Thus, the changes in the hemostatic molecular markers were associated with organ dysfunction from an early stage of sepsis, and antithrombin and protein C activities were found to be the most reliable markers.

Increased Plasma Levels of Soluble Thrombomodulin in Patients with Sepsis and Organ Failure

The fact that thrombomodulin (TM) is released into the bloodstream from damaged vascular endothelial cells led us to hypothesize that plasma levels of soluble TM could be an indicator of the development of organ failure. In this study, we examined the changes in plasma levels of TM in 60 septic patients and 13 postsurgical patients, and investigated the circulating levels of interleukin 6 (IL-6) and polymorphonuclear leukocyte elastase (PMN-E) to determine the mechanism causing the excess liberation of TM. The arterial ketone body ratio (AKBR) was also measured as an indicator of the hepatocyte energy state. Of the 60 septic patients, 26 developed organ failure, 10 of whom died. In contrast, none of the postsurgical patients developed organ failure. The mean plasma level of TM was significantly higher in the septic patients who developed organ failure compared to those without organ failure (P<0.001) or the postsurgical patients (P<0.001). Furthermore, those patients whose plasma TM values became elevated over 6.0ng/ml frequently developed complications. A positive correlation was also observed between the plasma TM levels and the IL-6 (P<0.01) and PMNE levels (P<0.01). In contrast, a negative correlation was seen between the plasma TM levels and the AKBR (P<0.01). These findings show that plasma TM could be a useful indicator of impending organ failure during sepsis.

Comparison of the protective effects of type III phosphodiesterase (PDE3) inhibitor (cilostazol) and acetylsalicylic acid on intestinal microcirculation after ischemia reperfusion injury in mice

ABSTRACT Antiplatelet therapy has been proposed as the treatment of choice for ischemia/reperfusion injury. The aim of this study is to elucidate the difference in effect between cilostazol (CZ) and acetylsalicylic acid (ASA) on microcirculatory disturbance in ischemia/reperfusion injury. Either 10 mg/kg of CZ (n = 14) or 100 mg/kg of ASA (n = 14) was administered orally to mice. Thereafter, 20 min of intestinal ischemia, followed by 60-min reperfusion, was applied; then, the status of submucosal microcirculation was observed under intravital microscopy. The blood cell counts and organ damage markers were examined in the portal blood. Next, 5 mm of the ileum was excised and was then histologically examined. Platelet-leukocyte aggregates were often observed in the postcapillary venules, and this formation was significantly reduced by both CZ and ASA. The number of adherent leukocytes was significantly lesser in the CZ-treated mice than in the ASA-treated mice (P < 0.01). The leukocyte number, lactate dehydrogenase, and lactate levels were best maintained in the CZ-treated mice (P < 0.05). The villus height was best preserved in the CZ-treated mice. Cilostazol inhibited not only the platelet aggregation but also the leukocyte adhesion to the endothelium, thereby inducing organ protection.

Factor Xa-inhibitor (DX-9065a) modulates the leukocyte-endothelial cell interaction in endotoxemic rat.

Abnormalities of vascular endothelial function and coagulation play important roles in the development of septic organ dysfunction. DX-9065a is a novel Factor Xa inhibitor that is expected to modulate both coagulation and endothelial function. The purpose of this study is to examine the effect of DX-9065a on leukocyte-endothelial interaction. Rats were injected with 1.0 mg/kg of endotoxin simultaneously with saline, (placebo group), 0.3 mg/kg DX-9065a (low-dose group), or 3.0 mg/kg DX-9065a (high-dose group;n = 6 in each group). At 1 and 3 h after injection, the mesenteric microcirculation was observed under intravital microscopy. In addition, TNF, IL-6, alanine aminotransferase (ALT), blood urea nitrogen (BUN), and lactate levels were measured. The number of leukocytes adhering to the endothelium was significantly reduced in both the high-dose and low-dose groups (P < 0.05 for both, compared to the control group). A comparison of the cytokine levels showed that the peak levels in the treatment groups tended to be lower. Markers of organ damage also showed less increase in the treatment groups (P < 0.05 for both treatment groups compared to the control group). In summary, the Factor Xa inhibitor DX-9065a showed a protective effect on the microcirculation of endotoxemic rats by attenuating leukocyte-endothelial interaction. Although the mechanism for this effect could not be fully elucidated, suppression of both excessive coagulation and cytokine production appear to play a role.

Pretreatment of sivelestat sodium hydrate improves the lung microcirculation and alveolar damage in lipopolysaccharide-induced acute lung inflammation in hamsters

ABSTRACT Damage to the lung microcirculation and alveoli caused by activated leukocytes is known to play an important role in the development of acute lung injury (ALI). The aim of this study is to evaluate the difference in the effect of pretreatment and posttreatment of a synthetic neutrophil elastase inhibitor sivelestat on ALI. Hamsters were instilled with 10.0 mg/kg of lipopolysaccharide (LPS) intratrachealy for 1 h to simulate ALI. Two milligrams per kilogram of sivelestat was injected intraperitoneally either previously or after LPS infusion. One and 24 hours after the infusion of LPS, pulmonary microcirculation was observed under the intravital microscopy. In another series, the blood cell counts were evaluated. The adhesive leukocyte count on the endothelium was significantly lower in pretreatment group compared with control group (P < 0.01), whereas the difference was not significant in the posttreatment group. Similarly, the number of obstructed capillary was significantly lower in the pretreatment group (P < 0.01). The width of interstitum was significantly lower in the pretreatment and posttreatment group (P < 0.01 and 0.05, respectively). A comparison of white blood cell counts showed a better maintenance in pretreatment group (P < 0.05). Pretreatment of sivelestat demonstrated a protective effect on both intravascular and extravascular damage in the lung, whereas posttreatment only suppressed the latter damage.

Laparoscopy-Assisted Low Anterior Resection with a Prolapsing Technique for Low Rectal Cancer

Laparoscopy-assisted low anterior resection (LAR) for low rectal cancer is a difficult procedure, presenting problems with rectal washout, selecting the appropriate distal transection line, and achieving safe anastomosis. To resolve these problems, we used a prolapsing technique to perform laparoscopy-assisted LAR. Total mesorectal excision (TME) is performed laparoscopically. The proximal colon is transected laparoscopically with the aid of an endoscopic stapler, and the distal rectum, including the lesion, are everted and pulled transanally to outside the body. Only washout of and wiping off the distal rectum and intestinal resection are performed extracorporeally. The distal rectum is pushed back through the anus into the pelvis, and intracorporeal anastomosis is completed laparoscopically with a double-stapling technique. Our limited experience suggests that the prolapsing technique helps to prevent problems with laparoscopy-assisted LAR in selected patients with low rectal cancer.

High-dose antithrombin therapy for sepsis: mechanisms of action.

Although extensive antithrombin (AT) supplementation has been shown to attenuate extent of organ failure and reduce the duration of disseminated intravascular coagulation (DIC) in septic patients, it has not yet been possible to show an improved survival rate (1–3). The concept of these sepsis trials is unique; that is, the natural coagulation inhibitor AT improves not only coagulation abnormalities or DIC, but also improves septic organ dysfunction (4). However, for that purpose, the physiological level of AT is insufficient, and 140– 160% of the normal activity, which is obtained after administration of pharmacological dose of AT, is required to attain the full efficacy (5). Because this efficacy of AT to improve organ dysfunction and survival cannot be explained by its anticoagulatory effect itself, the so-called “anti-inflammatory effect” has recently been advocated (6). Although success in the animal models is no guarantee of success in the clinic, former reports on the efficacy of AT in clinical sepsis suggest that the results of the studies in animal models can be translated into clinical efficacy (7, 8). Furthermore, the experimental investigations of AT in septic models have fulfilled all the recommended steps proposed by a recent expert panel on animal models in sepsis (9). Therefore, in this article, we summarize information from experimental data that is currently available regarding the “antiinflammatory effect” of AT, which includes effects on the coagulation system, PGI2 production, cytokine production, and leukocyte-endothelial interaction (Fig. 1).

Kinetics of cytokines and PMN-E in thoracoscopic esophagectomy

BACKGROUND Perioperative increases in the levels of cytokines and polymorphonuclear leukocyte elastase (PMN-E) have been shown to be related to degree of surgical trauma. METHODS We measured the changes in levels of interleukin-6 (IL-6), interleukin-8 (IL-8), and PMN-E in the perioperative period in patients undergoing thoracoscopic esophagectomy (n = 15) and conventional transthoracic esophagectomy (n = 15) for thoracic esophageal cancer. RESULTS Both IL-6 and IL-8 increased markedly immediately after transthoracic esophagectomy and thereafter, but only a slight increase was observed after the thoracoscopic procedure (IL-6: p = 0.047; IL-8: p = 0.03). A difference was also seen in the pattern of changes in PMN-E. Levels of PMN-E increased immediately after transthoracic esophagectomy and continued to be high up to the 3rd postoperative day, but they remained low after the thoracoscopic procedure and showed no increase (p <lt; 0.01). CONCLUSION These results suggest that, compared with transthoracic esophagectomy, thoracoscopic esophagectomy results in less production of cytokines and PMN-E and thus causes less surgical trauma.