Biomedical subjects

L Barker

Publications and source records attributed to L Barker.

40 records · Page 3Linked to original sources

PubMedDate not supplied

A disposable heart-lung machine. Results of animal testing.

A small wave propagation pump (WPP) was incorporated into oxygenators to create a disposable heart-lung machine. The WPP provides undirectional micropulsatile laminar flow of 8 L/min against 800 mmHg. The smaller WPP can generate 4 L/min against 400 mmHg (cardioplegia), or reversed, and can create up to 150 mmHg negative pressure for suction. Power needs were 110 volts and 0.5 amps or 24 volts DC and 1.5 amps. The WPP is self priming (20 cc) and de-aired in less than 3 min. Seven dogs (average weight, 36 kg) were supported for 3 hrs. Flows could accurately be adjusted from 0.005 to 8 L/min. Flow through the oxygenator and perfusion circuit averaged 3.1 L/min (2.0 to 4 L/min). Serial analysis of blood samples showed minimal hemolysis and no significant change in hematocrit, hemoglobin, white blood count, red blood count, or platelet count (p > 0.01). The inexpensive WPP oxygenator combination function as a disposable heart-lung machine.

Animals↗

PubMedDate not supplied

Using magnostrictive metal as a pump for biomedical application.

A new theory of pumping fluids, including blood, has been developed using magnetostrictive technology. This new pump uses the magnetostrictive material known as Terfenol-DTM. A magnetic field is imposed on the Terfenol in periodic pulses causing it to expand and then relax to its original state. The expansion and relaxation of the terfenol cause a smooth, continuous flow of fluid. This pump is currently being built and will be tested as a left ventricular assist device, totally implantable artificial heart, or both.

Electric Power Supplies↗

PubMedDate not supplied

Hemopump support for the failing heart.

Under fluoroscopy, the hemopump is passed through the aortic valve into the left ventricle through a Gortex (WF Gore, Denver, CO) chimney sewn to a surgically exposed femoral artery. The system aspirates the left ventricular blood and actively pumps it into the aorta. Five patients (four men, one woman), aged 47-71 years (mean, 62 years), were candidates for hemopump support because of refractory cardiogenic shock. Three were recovering from repeated coronary artery bypass graft (CABG) surgery, and two required postoperative emergency CABG for failed percutaneous transluminal coronary angioplasty (PTCA). One patient died during insertion, and four had the hemo-pump successfully placed. All patients had low cardiac out-put and had intraaortic balloons in place. Average insertion time took 20 min, with maintenance on the hemopump for an average of 13 hr. One patient was maintained on the hemopump for 12 hr, but because of continued deterioration, was placed on a total artificial heart (Harvik 7-70). Patients 3 (hemopump inserted transthoracically) and 4 had the hemopump discontinued because of brain death, and the fifth survived. This patient is alive and working 1 yr later. The hemopump is an effective left ventricular support system that is less invasive than conventional transthoracic systems.

Aged↗

PubMedDate not supplied

Educating primary care providers about HIV disease: multidisciplinary interactive mechanisms.

As HIV-related prophylactic and therapeutic research findings continue to evolve, the Health Resources and Services Administration (HRSA) of the Public Health Service has created multidisciplinary mechanisms to disseminate new treatment options and educate primary care providers at rural and urban sites throughout our nation's health care system. HRSA has implemented (a) the International State-of-the-Art HIV Clinical Conference Call Series, (b) the national network of AIDS Education and Training Centers, (c) the nationwide HIV Telephone Consultation Service, and (d) the Clinical Issues Subcommittee of the HRSA AIDS Advisory Committee. These collaborative and comprehensive efforts at HIV information dissemination target physicians, nurses, physician assistants, dentists, clinical pharmacists, mental health care providers, case managers, and allied health professionals. The sites where they provide care include public health clinics; county, State and Federal correctional facilities; private practice offices; community and academic hospitals; military and Veterans Administration facilities; hemophilia centers; schools of medicine, nursing, and dentistry; departments of health; chronic care facilities; visiting nurse and home care agencies; health maintenance organizations; and Indian Health Service clinics and hospitals.

Diffusion of Innovation↗