Clinical Research

Members of our faculty have maintained their significant contributions to medical/scientific literature and have continued to play active roles in professional and research societies. Our clinical research faculty examine acute and chronic pain, acupuncture, noninvasive monitoring of cardiovascular function, echocardiography, myocardial preservation during open heart surgery, psychological evaluations of children undergoing surgery, noninvasive monitoring of brain temperature and many other topics.

Among its outstanding features, the Yale University School of Medicine/Yale- New Haven Hospital medical complex offers the potential for collaboration with experts in a wide variety of fields. In addition to the aforementioned collaboration among clinical investigators and basic scientists within our Department, members of our Department have collaborated with clinicians and scientists in a variety of Departments within our Medical Center.

One area of focus in clinical research is the non-invasive assessment of cardiovascular function and volume status. Using a multi-dimensional computerized data acquisition system, we are integrating input from arterioles and capillaries (laser Doppler flowmetry), arteries and veins (plethysmography), with continuous monitors of blood pressure and heart rate to gain insight into two major areas of cardiovascular physiology: a) the regulation of microvascular perfusion, with a focus on autonomically- mediated autoregulatory processes in patients (with disorders such as diabetes) and helathy volunteers; b) the assessment of the cardiovascular responses to volume loss intraoperatively and in healthy volunteers (withdrawal and reinfusion of two units of blood; simulated hypovolemia with the use of lower body negative pressure).

To study the impact of anesthetics on brain function and metabolism, faculty members use magnetic resonance imaging. Functional MR imaging is an objective method of studying the subjective effects of anesthesia. fMRI can measure BOLD (blood oxygen level dependent contrast) a qualitative measure of cerebral metabolism and regional cerebral blood flow (rCBF). BOLD and rCBF are indirect measures of neuronal activity. In collaboration with the MRRC (magnetic resonance research center) we have been studying healthy ASA I volunteers under sevoflurane anesthesia. We study the effect of sevoflurane 0.25 and 0.5 MAC as well as the effect of activation under anesthesia. So far, close to 80 subjects have been imaged. In our first protocol the effect of visual, auditory and motor activation was studied under 0.25 MAC sevoflurane. Cerebral metabolism (BOLD) as well as rCBF was measured, providing direct information on the physiological effects on anesthetics on brains of normal patients.

Other faculty have looked at the effects of hypnosis on perioperative setting. In addition, our faculty have worked to implement a wellness program in anesthesiology residents at Yale, to study its impact on quality of life, stress levels, etc.

Dr. Barash, a former chairman of Anesthesia at Yale, is currently conducting research in two areas: (1) peri-operative cardiovascular anesthesia and (2) healthcare delivery. In particular working with Dr. John Elefteriades (Chief Cardiac Surgery), he is utilizing intra-operative echocardiographic imaging techniques to elucidate the mechanical properties of thoracic aortic aneurysms. Using Quality Assurance databases and information directly gathered in the operating rooms, Dr. Barash and his team are evaluating the logistics of delivering anesthetic care in an inpatient operating room suite of an academic medical center.