[Anesthetic management of MICS with Port-Access system].

Port-Access system (P-A) is a catheter-based system for minimally invasive cardiac surgery (MICS) characterized by avoidance of full sternotomy with the aid of Endoaortic Clamp Catheter (EAC) for intra-aortic occlusion instead of the conventional external aortic crossclamping. In our hospital, eleven patients underwent MICS using P-A from August in 1998 to the present time. We compared the intra- and post-operative anesthetic management of these patients with that of fifteen patients done by using our conventional MICS method, Saitama Medical School system (SMS). Anesthetic management of these MICS patients is directed toward early extubation, and therefore all patients receive intravenous anesthesia with a small dose of fentanyl combined with inhalational agent or propofol. Without increasing the time of the cardiopulmonary bypass (CPB) and the amount of the intraoperative bleeding, MICS with P-A needs more time to begin CPB than that with SMS because it takes more time to insert these catheters, especially EAC into the suitable position using transesophageal echocardiography (TEE) and fluoroscopy. The time to start CPB must be shortened by skilled cannulation. There is no difference in the postoperative length of ICU and hospital stays between P-A and SMS. In MICS, TEE is the window to the heart for both surgeon and anesthesiologist and used to guide for the placing of the catheters and weaning from CPB, and anesthesiologist should be skillful in using TEE to evaluate the de-airing procedure and assess volume load and contractility of the left ventricle.

[The application of the endotoxin test for globulin and other blood products].

The application of the endotoxin test for globulin and other blood products were investigated by two different limulus amebocyte lysate (LAL) test methods, colorimetric and kinetic turbidimetric methods, using two endotoxin-specific reagents. By the dilution of the blood products in 40 times or more, spiked endotoxin in the products was recovered accurately showing neither inhibition nor enhancement. The definite difference was not shown between the results obtained by the two LAL test methods. According to the method of the endotoxin test described under General Tests of The Japanese Pharmacopeia (thirteenth edition), JPXIII, the maximum valid dilution (MVD) for these products will be calculated to be 40 or more, so it is capable to measure the endotoxin limit for each product. This study indicates that the endotoxin test is applicable to measure the endotoxin content in globulin and other blood products as an alternative method for the rabbit pyrogen test.

[Ultrasound biomicroscopic imaging diagnosis of the anterior segment of the eye with high-frequency ultrasonic diagnostic equipment].

Micro-imaging displays of the anterior segment of the eye, such as of the anterior chamber angle, iris, ciliary body, ciliary zonule of Zinn, and anterior surface of the crystalline lens, were obtained in human eyes in vivo by means of a recently developed, high-frequency, high-resolution ultrasonic diagnostic unit (30 MHz). Much clearer displays than conventional ultrasonic imaging displays (5-15 MHz) were obtained, showing improved resolution, and greater morphologic diagnostic information was provided. Displays considered useful for making measurements were also provided. The subjects were 20 normal volunteers (35 eyes), 36 patients with glaucoma (58 eyes), 6 patients with uveal diseases (6 eyes), and 28 patients with pseudophakia (32 eyes). The equipment used was a model UX-02 ultrasonic diagnostic unit (RION), and the transducer was the three-element annular array type. The frequency was 30 MHz, the resolution was below 50 microns, and tissue penetration was 6 mm. This method enabled close ultrasound biomicroscopic imaging observations of details of the anterior and posterior chambers of the eyes in vivo and was also useful for clinical diagnosis and elucidation of the cause of glaucoma of various types. It also for the first time enabled evaluation of the position of fixation of an intraocular lens loop in the pseudophakic eyes containing an intraocular lens.

Myocardial contractility and ventricular myosin isoenzymes as influenced by cardiac hypertrophy and its regression.

Changes in myocardial contractility and ventricular myosin isoenzymes were examined during pressure-overloaded cardiac hypertrophy in rats. Effects of regression of cardiac hypertrophy were also examined. Cardiac hypertrophy was induced by abdominal aortic constriction in 7-week-old male Wistar rats. Regression of cardiac hypertrophy was obtained by opening the aortic band. Myocardial contractility was estimated by measuring isometrically developed tension and maximum rate of tension rise (+dT/dtmax) in isolated left-ventricular papillary muscles perfused with Tyrode solution (32 degrees C, pH 7.4, bubbled with 95% O2.5% CO2, stimulation frequency: 0.2 Hz). Left-ventricular myosin isoenzymes were separated by pyrophosphate gel electrophoresis and the isoenzyme pattern was determined by densitometry. Isometrically developed tension (T) in hypertrophic myocardium remained unchanged, but +/-dT/dtmax decreased as compared with hearts of normal rats. Decreased +/-dT/dtmax recovered near to the level in normal rats by regression of cardiac hypertrophy. Left-ventricular myosin isoenzyme pattern shifted towards VM-3 in hypertrophied myocardium and shifted again toward VM-1 by regression of cardiac hypertrophy. In conclusion, myocardial contractility and ventricular myosin isoenzymes were changed in pressure-overloaded hypertrophy in rats and these changes were reversible to a normal level by regression of cardiac hypertrophy.

Effects of regression of cardiac hypertrophy on myocardial contractility and ventricular myosin isoenzymes.

The effects of regression of cardiac hypertrophy on myocardial contractility and ventricular myosin isoenzymes were investigated in rats with renovascular hypertension. Six-week-old male Wistar rats were made hypertensive by constriction of one renal artery with a silver clip. Regression of cardiac hypertrophy was induced following the lowering of blood pressure by nephrectomy on the affected side 5-6 weeks after constriction of the renal artery and was maintained for 5-6 weeks. In contrast, myocardial hypertrophy was induced by 10-11 weeks of the hypertensive state. Isometric developed tension of isolated left ventricular papillary muscles was measured, while they were being perfused with Tyrode solution. Left ventricular myosin isoenzymes were separated by pyrophosphate gel electrophoresis. The ventricular to body weight ratio of the nephrectomized group was significantly lower than that of the hypertensive group, although it was greater than that of age-matched normal control rats. There were no significant differences in the isometric developed tension among three groups, the nephrectomized, hypertensive, and normal control rats. However, dT/dtmax tended to decrease in the hypertensive rats and recovered to normal in the nephrectomized rats. The left ventricular myosin isoenzyme pattern was shifted toward VM-3 in hypertensive rats and was shifted back toward VM-1 again in nephrectomized rats.