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J waves appear on an electrocardiogram as an elevation of the J point in the terminal portion of the QRS complex. J waves are often benign, but may be associated with malignant ventricular arrhythmias. In some cases, such problems appear to have been precipitated by propofol infusions. We observed a sudden increase in J waves and profound hypotension following a single intravenous dose of propofol in an 84-year-old woman with early repolarisation in the inferior ventricular wall. When early repolarisation (as shown by electrocardiographic J waves) is observed in the inferior ventricular wall pre-operatively, patients should be carefully monitored. Myocardial ischaemia and the use of drugs that might worsen J waves should be avoided. [ABSTRACT FROM AUTHOR]

Paraneoplastic limbic encephalitis associated with ovarian teratoma has recently been related to the development of antibodies to specific heteromers of the N-methyl--aspartate receptor and exhibits various manifestations including psychiatric symptoms, hypoventilation, seizures and derangement of autonomic nervous system function. Although recovery can sometimes occur spontaneously, early tumour resection with immunotherapy facilitates earlier recovery. Herein, we describe anaesthetic management of a 20-year-old woman who developed general convulsions and decreased level of consciousness, whom we suspected of having paraneoplastic limbic encephalitis and was scheduled for left ovarian tumour resection. Anaesthetic management was successful with no complications but the case acts as focus of discussion for the potential interaction of N-methyl--aspartate receptors and anaesthetic sensitivity. [ABSTRACT FROM AUTHOR]

This paper presents a new type of CMOS time-of-flight (TOF) range image sensor using single-layer gates on field oxide structure for photo conversion and charge transfer. This simple structure allows the realization of a dense TOF range imaging array with 1515 mum2 pixels in a standard CMOS process. Only an additional process step to create an n-type buried layer which is necessary for high-speed charge transfer is added to the fabrication process. The sensor operates based on time-delay dependent modulation of photocharge induced by back reflected infrared light pulses from an active illumination light source. To reduce the influence of background light, a small duty cycle light pulse is used and charge draining structures are included in the pixel. The TOF sensor chip fabricated measures a range resolution of 2.35 cm at 30 frames per second and an improvement to 0.74 cm at three frames per second with a pulsewidth of 100 ns. [ABSTRACT FROM PUBLISHER]

A wide-dynamic-range CMOS image sensor based on synthesis of one long and multiple short exposure-time signals is proposed. A high-speed, high-resolution column-parallel integration type analog-to-digital converter (ADC) with a nonlinear slope is crucial for this purpose. A prototype wide-dynamic-range CMOS image sensor that captures one long and three short exposure-time signals has been developed using 0.25-mum 1-poly 4-metal CMOS image sensor technology. The dynamic range of the prototype sensor is expanded by a factor of 121.5, compared with the case of a single long exposure time. The maximum DNL of the ADC is 0.3 least significant bits (LSB) for the single-resolution mode and 0.7 LSB for the multiresolution mode [ABSTRACT FROM PUBLISHER]

A new type of small magnetic rotary encoder is presented. The device detects the magnetic field of a permanent magnet attached to the end of the rotating shaft using complementary metal-oxide semiconductor (CMOS) magnetic sensors [magnetic field effect transistor (MAGFET) arrays] set in a square arrangement. The sensor array is integrated onto a CMOS chip along with angle-detection circuits, leading to the realization of a compact, cost-effective rotary encoder. A prototype sensor chip with dimensions of 4.3×4.3 mm2 is shown to provide error as low as 3.5° without offset calibration and 0.36° with offset calibration, based on an angle calculation method with mean square estimation. This result shows that the CMOS rotary encoder can achieve resolution of 10 bits/rotation at the cost of calibration. [ABSTRACT FROM PUBLISHER]

Background: Acute normovolemic hemodilution (ANH) causes a decrease in systemic vascular resistance. Similar to vasodilating drugs, ANH might modify ventriculoarterial coupling. Left ventricular elastance (Ees), effective arterial elastance (Ea), stroke work (SW), and pressure volume area (PVA) were used as indicators to examine the effects of ANH on this coupling.Methods: After institutional approval eight dogs were anesthetized with isoflurane and subjected to measurements including aortic pressure, left ventricular (LV) pressure, and LV volume. Left ventricular volume was measured with a conductance catheter. Ees was determined as the slope of the end-systolic pressure-volume relationship. Ea was determined as the ratio of LV end-systolic pressure to stroke volume. Ventriculoarterial coupling was evaluated as the ratio of Ees to Ea. Mechanical efficiency, another criterion for ventriculoarterial coupling, was calculated as the ratio of SW to PVA. Data are expressed as mean+/-SD, and P<0.05 was considered significant.Results: Normovolemic exchange of 50 ml kg-1 of blood for 6% hydroxyethyl starch (ANH50) reduced hemoglobin concentration from 12.8+/-3.0 g dl-1 to 6.4+/-1.3 g dl-1. Acute normovolemic hemodilution 50 did not change Ees significantly although it significantly decreased Ea. Left ventricular elastance/Ea did not change after ANH (1.0+/-0.4 at baseline and 1.2+/-0.5 at ANH50). Acute normovolemic hemodilution 50 significantly increased SW and PVA, preventing SW/PVA from changing significantly after ANH (0.57+/-0.10 at baseline and 0.62+/-0.14 at ANH50).Conclusion: Before ANH, ventriculoarterial coupling was so matched as to maximize SW at the expense of the work efficiency. This relation was preserved at ANH50. [ABSTRACT FROM AUTHOR]

Abstract: The Gyro C1E3 pump was developed not only for cardiopulmonary bypass but also as a short-term assist device. The main purpose of this study was to examine the correlation between the thrombus formation factor and the Gyro C1E3 pumps. Seven pumps were implanted into 3 calves and evaluated for different periods of duration as a paracorporeal left ventricular assist device (LVAD). One pump was subjected to percutaneous cardiopulmonary support condition (PCPS) (total pressure head 500 mm Hg with a pump flow rate of 3 L/min). The anticoagulation treatment consisted of a continuous administration of heparin to maintain an activated clotting time (ACT) of 200–250 during the LVAD study and 250–300 during the PCPS study. After the experiment, the pumps were disassembled and examined. In cases where there were any blood-derived deposits inside the pumps, the dry weight of these thrombi that adhered to the bearing area of the pump was measured. A multiple correlation was attempted to speculate possible thrombus formation. The estimated dry weight of thrombi was calculated from pump flow rate, pumping day, motor speed, and activated clotting time. This equation was estimated dry weight of thrombi = 1.140 × pump flow rate -0.001 motor speed + 1.652 pumping time -0.041 × ACT + 2.198 R2 = 0.944. This study suggested that there was a possibility to calculate the amount of adhered thrombus formation from pump flow rate, motor speed, pumping day, and ACT. [ABSTRACT FROM AUTHOR]

Background: The mechanisms of cardiovascular changes following acute normovolemic hemodilution (ANH) have not been fully elucidated. We tested the hypothesis that inhibition of nitric oxide synthesis attenuates ANH-induced cardiovascular responses.Methods: We observed the effects of N(omega)-nitro-L-arginine methyl ester (L-NAME) pretreatment on ANH-induced cardiovascular responses and compared these effects with those elicited by phenylephrine (PHE). Twenty dogs anesthetized with isoflurane were divided into two groups: one group was pretreated with L-NAME and the other with PHE. Both groups were normovolemically hemodiluted using 6% hydroxyethyl starch to reduce the hemoglobin concentration to approximately 50% of the pretreatment value.Results: Pretreatment with either L-NAME or PHE caused a significant increase in mean aortic blood pressure (MAP) and systemic vascular resistance (SVR) with a significant decrease in cardiac output (CO) and stroke volume (SV). However, no remarkable differences in these variables were seen between groups. In both groups ANH produced increases in heart rate, CO, SV, and maximal left ventricular dP/dt with a significant decrease in SVR. No significant differences in these variables were apparent after ANH except that MAP was decreased in the PHE group but not in the L-NAME group.Conclusion: Our results suggest that nitric oxide does not play a major role in mediation or modulation of the systemic vascular responses to ANH. [ABSTRACT FROM AUTHOR]