Effect of direct hemoperfusion using polymyxin B immobilized fiber on inflammatory mediators in patients with severe sepsis and septic shock.

The objective of this study was to investigate retrospectively the effect of direct hemoperfusion using polymyxin B immobilized fiber (PMX-DHP) in a cartridge to remove endotoxin on inflammatory mediators in septic patients. PMX-DHP was performed 59 times in 40 patients with severe sepsis and septic shock due to gram-negative bacterial infection. Mean age and APACHE II score were 63 years and 22, respectively. The first treatments with PMX-DHP were started when patient hemodynamics were unstable even after conventional therapies. The second treatments were performed in 19 patients whose hemodynamics were still unstable after the first PMX-DHP. The changes in inflammatory mediator levels were compared from baseline to post treatment with PMX-DHP. Statistical differences were calculated using the Wilcoxon rank sum test. Plasma endotoxin could be detected in 34 patients, which was significantly decreased in 20 cases measured by a chromogenic kinetic limulus amebocyte lysate assay (p=0.0254) and in 14 cases measured by a new limulus turbidimetric time assay (p=0.0196). Monocyte counts in peripheral blood decreased significantly (p=0.0402). Interleukin-6 decreased significantly (p=0.0020). Blood pyruvate also decreased significantly (p=0.0025). At the same time, mean arterial pressure, pulse pressure, systemic vascular resistance index, and urine output were significantly increased. These results indicated that PMX-DHP could decrease inflammatory mediators and be effective to interrupt the pathogenic sequence leading to septic shock due to gram-negative bacterial infection.

[Two cases of pericardial rupture due to blunt chest trauma].

We treated two cases of pericardial rupture from blunt chest trauma. Case 1: A 55-year-old male was injured in an automobile accident. He recovered from the left hemothorax by tube drainage. One year and two months after the trauma, a left pericardial rupture was found during an operation for a left diaphragmatic hernia. As the epicardium adhered firmly to the pericardium, the ruptured pericardium was not sutured. Case 2: A 46-year-old man fell from a tree five meters in height. Chest radiography showed multiple right rib fractures, a pelvic fracture, pneumopericardium, and right hemopneumothorax. After four days, we performed a thoracoscopic examination under local anesthesia. The thoracoscopy revealed a rupture as large as an egg in the right pericardium anterior to the phrenic nerve. Judging from the size of the rupture, cardiac luxation was suspected not to have occurred. So the defect was not repaired. These two patients were discharged uneventfully without cardiac luxation. In the future, the accumulation of thoracoscopic findings may provide adequate information for judging the indication of operative repair in pericardial ruptures.

[Four cases of airway infections caused by MRSA (methicillin resistant Staphylococcus aureus)].

Currently, infections caused by MRSA (methicillin-resistant Staphylococcus aureus) pose a great problem clinically. We present 4 patients with MRSA infections experienced by us. In these patients the infection was localized in the trachea and main bronchus. The first patient was a 62-year-old man. After undergoing operation for early gastric cancer, he had septic shock and was admitted to our center. The second was a 60-year-old man. After he underwent operation for advanced gastric carcinoma at another hospital septicemia developed due to suture failure and he was admitted to our center. The third was a 38-year-old woman who was admitted to our center because of grades II degrees-III degrees burns on 75 to 80% of her body surface area. The fourth was a 60-year-old man who was admitted to our center because of rupture of an aneurysm of the abdominal aorta. It is assumed that MRSA has quite different characteristics from the usual MSSA (methicillin-sensitive Staphylococcus aureus) in that it produces a new penicillin-bound protein (PBP-2') within cells. Thus, from the fiberoptic bronchoscopy findings of our own cases it is considered that there may be cases in which the observed lesion is localized in the central airway alone, without involvement of the segmental bronchi. We believe it necessary to take some prompt measures under a suspicion of airway infection caused by MRSA in the following cases: (1) compromised hosts under tracheal intubation, (2) patients who are under treatment with second or third generation cephalosporins, and (3) patients with production of bloody sputum, and (4) endotoxin-positive patients.

Application of dipole analysis for the diagnosis of myocardial infarction in the presence of left bundle branch block.

The residue value on dipole analysis (the ratio of non-dipolar component to the measured body surface potentials) was estimated mathematically in 16 patients with left bundle branch block. Patients were classified into those with (group A, nine patients) and those without (group B, seven patients) a perfusion defect on thallium-201 myocardial scintigraphy. For the entire QRS complex the residue of group B was smaller than that of normal subjects (20.0 +/- 4.1% versus 24.6 +/- 3.5%, p less than 0.05). Group A showed a greater mean residue value than group B (27.4 +/- 4.4% versus 20.3 +/- 2.4%, p less than 0.01) only during the initial one-third of the QRS complex. All but one patient of group A and only one patient in group B showed a high peak on the residue curve during the initial stage of the QRS complex. The maximal residue value of group A during the initial QRS complex was significantly greater than that of group B (40.9 +/- 10.9% versus 23.4 +/- 5.4%, p less than 0.01). An arbitrarily selected criterion of the maximal residue value greater than or equal to 30% during the initial QRS complex showed a sensitivity of 89% with a specificity of 86% for the diagnosis of myocardial infarction in the presence of left bundle branch block. These results might be related to the complex ventricular activation around the infarcted area even in the presence of left bundle branch block in which intramyocardial conduction with a simple activation front predominates. Dipole analysis appeared to be a valuable method of diagnosing myocardial infarction in the presence of left bundle branch block.

Dipolarity and dipole location during QRS and T waves in normal men estimated from body surface potential distribution.

The dipolarity of the body surface potential distribution and the locus of the main dipole were estimated mathematically at 2 msec intervals in 27 normal men. The nondipolar content showed time-dependent fluctuation during the QRS. It increased sharply at early and later phases of the QRS. The main dipole moved smoothly within the actual cardiac region and was inscribed in a clockwise direction in most cases. The nondipolar content during the ST-T period was smaller and with less fluctuation than that during the QRS. The main dipole during the T wave moved less than 2 cm near the center of the heart. These results indicated that although a fairly large percentage of the body surface potential could be represented by a single moving dipole, the nondipolar content was larger during initial and late phases of the QRS. It was also suggested that the ventricular repolarization process can be better approximated by a single fixed dipole in normal men.