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Biomedical subjects

R K White

Publications and source records attributed to R K White.

29 records · Page 2Linked to original sources

Brain transplantation: prolonged survival of brain after carotid-jugular interposition.

Six isolated canine brains were successfully transplanted for 6 hours to 2 days to the cervical vasculature of dogs. Viability was shown by electrocortical activity and significant uptakes of oxygen and glucose, with production of carbon dioxide. Cerebral blood flows, temperatures, and pressures of the cerebral homograft were continuously monitored by way of an implantable recording module.

Animals↗

Microbially infected thrombus in animals with total artificial hearts.

In a retrospective study of 330 animals with total artificial hearts (TAH), 103 (31%) had microbially infected thrombi (MIT). The incidence of MIT approximated 75% in the animals surviving more than 100 days. The most common pathogen isolated from animals with MIT was Pseudomonas. Most thrombi appeared to have originated from valve junctions and connectors. Methods to prevent MIT should be aimed at eliminating thrombus formation by improved design and materials and controlling the route of bacterial colonization. These findings suggest that bacterial interaction with the thrombus, device-related bacterial colonization, host immunomodulation, and gut barrier function after TAH implantation need further study.

Animals↗

Comparison of microsphere and intraoperative quantitation of bronchial blood flow.

Although significant variation in bronchial blood flow (BBF) has been reported, precise quantitation is difficult because of the small sized vessels and variable anatomy. Ventricular balance is critical to the function of the total artificial heart (TAH), and variation in BBF can alter this balance in the bovine model. Bronchial blood flow was measured in 12 calves by two methods: six by the radioactive labeled microsphere technique (MBBF), and six intraoperatively (IBBF) during cardiopulmonary bypass (CPB). In the MBBF group, BBF ranged from 1.9 ml/kg to 16.0 ml/kg, whereas IBBF varied from 2.6 ml/kg to 10 ml/kg (NS). Cardiac output (CO) was significantly higher (p less than 0.0005) in the MBBF group. Bronchial blood flow in both groups was highly variable. The higher flow in the MBBF group may be attributed to the arteriovenous shunting of microspheres, whereas lower flow in the IBBF group may be secondary to physiologic changes during CPB. This technique, described to measure IBBF, can estimate large variations in the natural right to left shunt that contributes to imbalance in the TAH.

Animals↗