Biomedical subjects
Publications and source records attributed to W Ko.
Central serous chorioretinopathy is an infrequent but benign complication of pregnancy that is found largely in the minority population. White subretinal exudates and multiple recurrences are frequently seen with the central serous chorioretinopathy of pregnancy. Central serous chorioretinopathy usually spontaneously resolves with minimal sequelae without intervention after delivery of the baby.
To define the optimal and safe storage period in the use of the University of Wisconsin Solution (UWS) for extended heart preservation, 34 adult canine hearts were preserved under static and hypothermic conditions for 6, 12, 18, and 24 hours. A group of 10 hearts were used as a control of the preparation used in the study. Left ventricular functions were assessed in an isolated heart preparation equipped with a computerized servo-pump to measure the pressure-volume relationship. The systolic, diastolic and total ventricular performance were derived from the end-systolic pressure-volume relationship, end diastolic pressure-volume pressure relationship, and the stroke work-end diastolic volume relationship, respectively. Myocardial water content and coronary resistance during reperfusion were also analyzed. The study revealed that UWS was able to maintain normal levels of systolic and diastolic functions, and consequently normal level of total ventricular performance after 6 hours of storage. There was a reduction of diastolic function while the systolic function was still well maintained after 12 hours of preservation. The results after 12 hours were poor. There was no increase in the myocardial water content for up to 24 hours of storage; however, the coronary resistance during reperfusion significantly increased in the 18-hour group and the 24-hour group. The findings suggest that UWS may extend the safe period of myocardial preservation beyond the traditional 4 hours of storage closer to 12 hours of storage.
A valveless, single orifice polyurethane ventricle was implanted on the brachiocephalic artery in sheep (n = 14) to provide extraaortic counterpulsation. In parallel, an intraaortic balloon was placed in the descending thoracic aorta. Both devices were pneumatically driven by a standard intraaortic balloon pump (IABP) console at a preload of 40 cc. Severe cardiac failure was induced with high dosages of esmolol. Measured parameters were aortic pressure (PA) and flow (QA), coronary flow (QC), and left ventricular pressure (PLV). Tension time index (TTI), total QA and QC, and end-diastolic aortic pressure (EDP) were computed to compare the efficacy of counterpulsation between assisted and unassisted conditions. Three conditions of inflation/deflation timing were examined: Normal timing (NT), early inflation (EI), and late deflation (LD). Results indicated that extraaortic counterpulsation device actuation yielded statistically significant increases in QC, and significant decreases in EDP and TTI for all timing conditions examined, when compared with unassisted conditions. Flow was significantly increased only for EI and NT timing conditions. Counterpulsation delivered with IABP yielded statistically significant increases in EDP for LD timing, and significant decreases in TTI for NT only. These results indicate that EACD is much less dependent on inflation/deflation timing when compared with IABP. The extraaortic counterpulsation device consistently increases QC and decreases TTI, which enhances the oxygen supply/consumption ratio (S/C) of the left ventricle. The intraaortic balloon pump does not significantly increase S/C in severe cardiac failure, and will increase afterload if deflation timing is not properly set.
Neurofibromatosis is an autosomal dominant disease with multiple systemic and ocular signs and features. The ocular manifestations of neurofibromatosis include a high incidence of iris hamartomas (Lisch nodules), choroidal hamartomas, and eye lid neurofibromas. Other ocular features may include conjunctival neurofibromas, prominent corneal nerves, glial tissue overlying the optic nerve, and bilateral optic atrophy due to optic glioma. Once neurofibromatosis is diagnosed, patients must have long-term ophthalmic evaluations throughout their lifetime, as this is a progressive systemic and ocular disease.
PURPOSE: A multidisciplinary project was undertaken at The New York Hospital-Cornell Medical Center to develop critical pathways for open-heart surgery to help reduce cost, shorten hospital length of stay (LOS), and streamline patient care. METHODS: A critical pathway for elective coronary artery bypass grafting instituted on March 1, 1995, was developed through a cooperative effort involving surgeons, anesthesiologists, nurses, social workers, physical therapists, nutritionists, and patient case managers. Prospective data collected on consecutive patients forming a critical pathway group (n = 114) over a 6-month period were compared with retrospective data on consecutive patients forming a cohort group (n = 382) who underwent elective coronary artery bypass grafting in 1994. RESULTS: The critical pathway group of patients experienced a significantly shorter total hospital LOS (7.7 +/- 2.3 days vs 11.1 +/- 6 days, p < 0.0001) and shorter intensive care unit LOS (1.5 +/- 0.9 days vs 2.0 +/- 2.8 days, p < 0.0001). Direct costs were computed by use of hospital charges multiplied by the Medicare cost-to-charge ratio. Mean hospital direct cost (ancillary resources) was $1181 lower in the critical pathway group when compared with the control group (p < 0.0001). The postoperative mortality and readmission rates were similar for the two groups of patients. CONCLUSIONS: The ongoing analysis of cost, LOSs, and outcomes has made possible a process of continuous quality improvement on the cardiothoracic service in which further areas for improvement are identified and studied. The use of a critical pathway for elective coronary artery bypass grafting at our institution significantly reduced hospital LOS and direct costs while maintaining the overall quality of patient care.