Simon Hillier

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Pulmonary microvessels (<70 microm) lack a complete muscular media. We tested the hypothesis that these thin-walled vessels do not participate in the hypoxic pressor response. Isolated canine lobes were pump perfused at precisely known microvascular pressures. A videomicroscope, coupled to a computerized image-enhancement system, permitted accurate diameter(More)
Pulmonary hypertension frequently complicates the postoperative management of patients after congenital cardiac surgery. Inhaled nitric oxide is an effective treatment option, but rebound pulmonary hypertension can occur upon its withdrawal. Sildenafil may facilitate its withdrawal by restoring cyclic guanosine monophosphate availability via(More)
Profound hypothermic circulatory arrest (PHCA) is followed by a transient period of increased intracranial pressure and a longer period of neurophysiologic dysfunction. To investigate the effect of cardiopulmonary bypass (CPB) with PHCA on cerebral hemodynamics, we used transcranial Doppler sonography to measure cerebral blood flow velocity in 10 neonates(More)
The piglet scaled cortical impact model creates a focal contusion using a skull-mounted, spring-loaded blunt indentation device scaled to achieve identical tissue strains in subjects with different brain sizes. Preliminary data showed that contusion size increased proportional to subject age. This study details the results from a new, larger series of(More)
Severe veno-occlusive disease (VOD) of the liver is a frequent cause of morbidity and mortality in patients undergoing transplantation. While surgical portosystemic shunts have been reported to be useful in the treatment of severe hepatic VOD with intractable ascites, few of these patients are surgical candidates. We report a case of severe VOD after(More)
Pulmonary vascular distensibility has an important influence on pulmonary hemodynamics. Although many measurements of distensibility have been made on large pulmonary vessels, there is less information on microvascular distensibility. We have measured the distensibility of the smallest (< 70-microns-diam) precapillary arterioles and postcapillary venules.(More)
Direct laryngoscopy and tracheal intubation may be associated with increased heart rate, arterial blood pressure, cardiac index, and systemic vascular resistance. These responses have been attributed to sympathoadrenal stimulation. However, the studies measuring distribution of blood flow to various organs are limited. We prospectively evaluated blood flow(More)
One mission of medical informatics is to provide physicians, nurses, and other health care providers with the technology and tools for interpreting large and diverse data sets, so that appropriate critical care decisions can be facilitated. Ideally, medical data visualization provides the means to transform data into information and contextual knowledge(More)
To directly determine the pressure-diameter relationship of individual pulmonary microvessels, it is necessary to measure the width of the column of blood in the vessel because microvascular walls are invisible when using intravital microscopy. To identify the margins of the blood column accurately, we developed a method for computer enhancement and(More)
A peripheral indicator of the presence and magnitude of brain injury has been a sought-after tool by clinicians. We measured neuron-specific enolase (NSE), myelin basic protein (MBP), and S100B, prior to and after scaled cortical impact in immature pigs, to determine if these purported markers increase after injury, correlate with the resulting lesion(More)