Jun Kawasaki

Electron microscopic evaluations of clot morphology during thrombelastography

In this study, we characterized clot morphology with a scanning electron microscope (SEM) at time points corresponding to the commonly used thrombelastography (TEG®) variables, illustrating the correlation of the physical clot formation with TEG® tracings. The first channel of the TEG® analyzer was used to obtain the tracings of clot formation, while the sub-samples for the SEM were obtained from the second TEG® channel. Different types of samples were examined, including whole blood, abciximab-treated whole blood, platelet-rich plasma (PRP), and abciximab-treated PRP. The SEM images were obtained at reaction time, different amplitudes (5–30 mm), maximum amplitude (MA), and at amplitude 60 min after MA. In the whole blood, coarse fibrin and activated platelets were observed at reaction time and fibrin strands progressively became more solid and intertwined at amplitude 10 mm and thereafter. Red blood cells were surrounded with fibrin strands at amplitude 30 mm and were tightly packed by fibrin strands at MA. In abciximab-treated whole blood, red blood cell shape was maintained at MA. The process of fibrin formation and platelet activation was also examined in PRP. Abciximab did not block platelet shape change, although the blockage of fibrin binding to platelets was shown on the TEG® analyzer. In summary, we have shown structural changes of the forming clot in relation to TEG® variables.

Blood component therapy guided by celite-activated thromboelastography for perioperative coagulopathy

Case 1 was a 54-year-old man (weight, 65kg; height, 160cm), who while a bicycling was involved in a head-on collision with a truck. He was brought to the emergency room with findings of a slightly depressed level of consciousness (Glasgow Coma Scale [GCS]II score of 4). His abdomen was distended, and computed tomography (CT) scanning revealed a highresolution lesion that was widespread throughout the mesentery, consistent with intraabdominal bleeding. He was orally intubated, and 1800ml of packed red blood cells (RBC) was administered in the emergency room. Subsequently, he was brought to the operating room for exploratory laparotomy. General anesthesia was maintained with O2 and sevoflurane. We were not able to detect any clot formation on celite-activated TEG immediately after induction of anesthesia (Fig. 1A). The patient showed continuous bleeding, which required crystalloid 5700ml; RBC 3600 ml; and fresh frozen plasma (FFP), 1200ml. Tranexamic acid 1500mg was given because increased fibrinolysis was also suspected from the minimal clot formation. Blood loss was estimated as 12000 ml by the time surgical hemostasis was established. Subsequent TEG showed near-normal reaction (R) time (8.3min), but severely decreased α angle and maximum amplitude (MA; 23° and 19mm), suggesting decreased platelet count (Fig. 1B). It also showed hyperfibrinolysis (Lysis index at 60min [LY60], 17.5%). Platelet count was measured together with the second TEG, and it was 23000/mm3, consistent with a reduced α angle and MA. Thirty-five units of platelets, FFP 560ml, and tranexamic acid 1000mg were given. At the end of the surgery, TEG showed near-normal values (Fig. 1C; R, 2.5min; α, 54°; MA, 47mm; and LY60, 5.5%). There was no increased bleeding from the drainage tube after the operation. Address correspondence to: J. Kawasaki Received: March 14, 2001 / Accepted: August 9, 2001

A Method for Studying Interaction Between Non-Deporalizing Neuromuscular Blockers and Other Drugs in Vivo

In view of clinical set, there are not so many methods for studying interactions between non-deporalizing neuromuscular blockers and other drugs. We schemed out a new methods for studying the interactions mentioned above.