Biomedical subjects

W Quiñones-Baldrich

Publications and source records attributed to W Quiñones-Baldrich.

4 recordsLinked to original sources

PubMed1998

Dexamethasone and enalapril suppress intimal hyperplasia individually but have no synergistic effect.

Vascular injury is associated with complex interactions that lead to development of intimal hyperplasia (IH). We have demonstrated previously that the corticosteroid dexamethasone and the ACE-inhibitor enalapril are effective in suppressing the development of IH. We hypothesize that due to distinctly different pharmacologic mechanisms of action, a synergistic effect would be expected if these agents were given in combination. Forty New Zealand White rabbits underwent balloon catheter denudation of the carotid artery. Animals were divided into four equal treatment groups and received daily intramuscular injections: Group 1, saline; Group 2, enalapril 0.07 mg/kg, Group 3, dexamethasone 0.125 mg/kg; and Group 4, enalapril 0.07 mg/kg plus dexamethasone 0.125 mg/kg. Vessels were harvested at 12 weeks and intimal hyperplasia was measured as a ratio of the absolute area of IH to the normalized area enclosed by the internal elastic lamina (IH/IEL). Mean values for IH/IEL are expressed as a percent (SD): Group 1, 32.31 (14.9); Group 2, 9.47 (2.11); Group 3, 5.40 (4.14); and Group 4, 8.49 (4.27). All treatment groups demonstrated significant suppression of IH compared to the control group (p < 0.01); dexamethasone was more effective than enalapril (p = 0.01). There was no statistical difference in IH suppression between respective agents and the combination group (p > 0.10). Coadministration of dexamethasone and enalapril provides no advantage over single-agent therapy in suppressing the development of IH, suggesting that maximal suppression is obtained with single-agent treatment or that these agents affect IH through a common pathway.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed1996

Intraoperative vascular endoscopy: early and late results.

In a prospective study, 60 consecutive cases of vascular endoscopy were analyzed to examine the role of angioscopy in infrainguinal vascular procedures. A total of 52 patients had 60 separate vascular endoscopy procedures performed as an adjunct to various vascular procedures; results of intraoperative arteriography were available in 38 of 60 cases. All patients were followed for at least 42 months. The 19 patients who underwent thrombectomy with angioscopy were compared with 19 age-matched control subjects who underwent infrainguinal thrombectomy without angioscopy to evaluate the influence of angioscopy on primary and secondary patency rates. Angioscopy allowed observation of 50 lesions; angiography failed to detect three. These findings altered surgical management in 24 cases (40%). Primary patency rates for the control and experimental thrombectomy groups were 38.8% and 6.5% at 42 months, respectively (p = 0.010 based on log-rank test). Secondary patency rates for the control and experimental groups at 42 months were 63.8% and 49%, respectively (p = 0.521). The limb salvage rate was 89% at 42 months for both groups (p = 0.973). Angioscopy provides the clinician with a direct view while he or she is performing vascular procedures. However, there was no statistical improvement in secondary patency and limb salvage rates. Furthermore, the use of angioscopy during thrombectomy may increase the propensity for subsequent intervention as evidenced by the frequency of changes in surgical management and the lower primary patency rate.

Adolescent↗

PubMed1992

Neonatal aortic thrombosis.

Thrombosis of the aorta in the neonate is a potentially catastrophic event. The incidence of this problem has increased concomitantly with the widespread use of umbilical artery catheters in the management of infants who are critically ill. The natural history and appropriate management of this complication has not been well established. This is due in part to the wide spectrum of presentations and lack of consensus regarding its classification. Aortic thrombosis may vary from deposition of a fibrin sheath surrounding the length of an umbilical artery catheter to aggregates of nonocclusive thrombus within the aorta or to complete occlusion of the aorta and concomitant occlusion of its main branches. The reported treatments recommended for this problem have ranged from supportive care only to mandatory surgical intervention in all cases. This spectrum of advocated therapies has resulted in considerable confusion regarding the proper management of this problem. This paper presents two cases of neonatal aortic thrombosis: one case was treated medically and the other case was treated with surgical intervention. We review these cases and the current literature, with specific attention directed towards highlighting the critical elements involved in formulating a reasonable approach to the management of neonatal aortic thrombosis. In addition, we offer an algorithm for management of these patients according to the degree of aortic thrombosis, severity of systemic manifestations, and the general condition of each individual patient.

Aortic Diseases↗

PubMed1991

Chylous ascites following abdominal aortic surgery.

Three patients, two women, one man (mean age 74 years), who had abdominal aortic aneurysms (2) or aortobifemoral surgery (1), developed chylous ascites postoperatively. They were studied to determine their clinical course and develop a plan for management of this complication. In each patient, the ascites was not manifest until abdominal swelling developed two weeks after operation, and the problem was confirmed by the finding of milky fluid on paracentesis. A low serum albumin (mean 2.6 gm) was also characteristic. The ascites was not altered by parenteral nutrition or reduction of dietary fat and ingestion of medium chain triglycerides. In one patient (man, age 93) the ascites resolved spontaneously two months after abdominal aortic aneurysm surgery. Another (woman, age 70) was cured following operative ligation of a lymphatic fistula identified at operation five weeks after abdominal aortic aneurysm repair. In the third (woman, age 60), the ascites resolved immediately following placement of a peritoneal venous shunt six weeks after an aortobifemoral bypass. Chylous ascites is rare after aortic surgery and manifests itself about two weeks after operation, at times after discharge from hospital. It has an indolent course, but may resolve spontaneously up to two months after operation. Its course appears not to be foreshortened by diet, including omission of fat, but can be successfully treated surgically with a shunt or fistula ligation. If done early a protracted hospital course may be avoided.

Aged↗