A technique is proposed for the design of a modified CMOS regulated cascode having an output impedance significantly greater than that of a conventional regulated cascode. Simulation results for an illustrative design, operating at 10μA from a 1V supply, show an increase in output resistance from 636MΩ and output bandwidth of 55kHz for a conventional circuit to 6.68GΩ and 389kHz, respectively, ...

Women with pulmonary hypertension have a high risk of morbidity and mortality during pregnancy. The inability to increase cardiac output leads to heart failure while further risks are introduced with hypercoagulability and decrease in systemic vascular resistance. There is no proof that new advanced therapies for pulmonary hypertension decrease the risk, though some promising results have been ...

BACKGROUND This simulation study investigated potential modulations of total peripheral resistance (TPR), due to distributed peripheral vascular activity, by means of a lumped model of the arterial tree and a non linear model of microcirculation, inclusive of local controls of blood flow and tissue-capillary fluid exchange. RESULTS Numerical simulations of circulation were carried out to comp...

This paper presents a model-based approach to estimation of cardiac output (CO) and total peripheral resistance (TPR). In the proposed approach, the response of cardiovascular system (CVS), described by the windkessel model, is tuned to the measurements of systolic, diastolic and mean arterial blood pressures (BP) so as to yield optimal individual- and time-specific system time constant that is...

1. Frequent measurements of arterial pressure, cardiac output, heart rate and body weight were carried out in three hypertensive anephric subjects during the reversal of hypertension by carefully controlled stepwise fluid withdrawal over a period of 24 days. 2. The initial 5% decrease of body weight was associated with decrements of arterial pressure and total peripheral resistance of 15 and 35...

Scaling of the Ino,52AI,,,,As insulator thickness of In,,~s2AI,,1,As/n+-Ine,s3Gao.J,As MIS-type FET’s is found experimentally to result in a drastic drop in performance below 200 A. This is demonstrated to arise from an increase in the sheet resistance of the extrinsic portions of the device that accompanies insulator scaling. In order to solve this problem, a recessed-gate MISFET with a very t...

The first haemodynamic change during pregnancy seems to be a rise in heart rate. Starting between two and five weeks this continues well into the third trimester. Stroke volume increases slightly later than the heart rate and continues throughout the second trimester after an augmentation of venous return and a fall of systemic vascular resistance and afterload. Myocardial contractility is prob...

Many basic concepts of cardiac output and arterial pressure control have changed considerably in the past few years. In general, each tissue controls its own local resistance and blood flow regardless of the level of arterial pressure; the sum of the local flows then determines the venous return and cardiac output. However, the arterial pressure is normally controlled by separate mechanisms tha...

Thirty male subjects, aged 29-69, were studied before and during stressful interviews. Coronary blood flow was measured using the radioactive Diodrast technique developed by Sevelius and Johnson. Blood pressure and pulse rate were also measured, cardiac output and peripheral resistance were calculated Significant alterations in these parameters occurred in a patterned way which corresponded to ...

Studies to more clearly determine the mechanisms associated with arginine vasopressin (AVP)-induced vasodilation were performed in normal subjects and in quadriplegic subjects with impaired efferent sympathetic responses. Studies to compare the effects of AVP with the hemodynamic effects of nitroglycerin, an agent that primarily affects venous capacitance vessels, were also performed in normal ...