Biomedical subjects

Carolyn L Kerrigan

Publications and source records attributed to Carolyn L Kerrigan.

7 recordsLinked to original sources

PubMed2005

Analysis of breast reduction complications derived from the BRAVO study.

BACKGROUND: Analysis of complication data derived from the Breast Reduction Assessment: Value and Outcomes (BRAVO) study, a 9-month prospective, multicenter trial, is presented. METHODS: Data derived from 179 patients were analyzed, including bivariate associations between complications and single predictor variables (Fisher's exact test or chi-square testing) or continuous variables (two-sample t test) and, finally, logistic regression. RESULTS: The overall complication rate was 43 percent (77 patients). Simple, bivariate analysis linked preoperative breast volume, shoulder strap grooving, and a vertical incision with an increased incidence of complications (p < 0.05, 0.02, and 0.02, respectively). Delayed wound healing, the most common complication, correlated directly with average preoperative breast volume (p < 0.045), average resection weight/breast (p < 0.027), and smoking (p < 0.029) and inversely with age (p < 0.011). Vertical incision techniques were associated with an increased complication frequency (p < 0.05) without a link to specific complications. Logistic regression analysis associated resection weight as the sole variable for increased risk of complications (p = 0.05) and with absolute number of complications [mean resection weight of 791 g for patients without complications versus 847, 882, and 1752 g for patients with one, two, and three complications, respectively (p = 0.0022)]. Each 10-fold increase in resection weight increased the risk of complication 4.8 times and increased the risk of delayed healing 11.6 times. CONCLUSIONS: Complication data revealed several significant features: (1) resection weight correlated with increased risk and absolute number of complications; (2) delayed healing correlated directly with resection weight and inversely with increasing age, anesthesia times, and preoperative Short Form-36 bodily pain score; (3) a vertical incision may be associated with increased incidence of complications but requires further analysis; and most importantly, (4) the presence of complications had no negative effect on improvement in Short Form-36 and Multidimensional Body-Self Relations Questionnaire scores.

Adult↗

PubMed2002

The effectiveness of surgical and nonsurgical interventions in relieving the symptoms of macromastia.

In this report, the authors evaluate the effectiveness of breast reduction in alleviating the symptoms of macromastia by comparing baseline and postoperative health status using a series of well-validated self-report instruments. The study had a prospective design with a surgical intervention group and two control groups: a hypertrophy control group with bra cup sizes D or larger and a normal control group with bra cup sizes less than D. The effectiveness of nonsurgical interventions in relieving the symptoms of macromastia was also evaluated, both in the operative subjects and in the control groups. Surgical candidates and controls completed a self-administered baseline survey that consisted of the following validated and standardized instruments commonly used to evaluate outcomes: SF-36, EuroQol, Multidimensional Body-Self Relations Questionnaire (MBSRQ), and the McGill Pain Questionnaire (MPQ). A specially designed and validated instrument, the Breast-Related Symptoms (BRS), was also used. There were also questions about prior nonsurgical treatments, comorbid conditions, bra size, and a physical assessment. Additional information obtained on the operative subjects included surgical procedure data, resection weight, and complications. Approximately 6 to 9 months postoperatively, surgical subjects completed the same questionnaire as described above, and a final physical assessment was performed. The cohort included 179 operative subjects with matched preoperative and postoperative data sets, 96 normal controls and 88 hypertrophy controls. The women were predominantly Caucasian, middle-aged, well educated, and employed. Fifty percent of the operative subjects reported breast-related pain all or most of the time in the upper back, shoulders, neck, and lower back preoperatively compared with less than 10 percent postoperatively. Operative subjects and hypertrophy controls tried a number of conservative treatments, including weight loss, but none provided adequate permanent relief. Compared with population norms, the preoperative subjects had significantly lower scores (p < 0.05) in all eight health domains of the SF-36, and in the mental and physical component summary scores. After surgery, the operative subjects had higher means (better health) than national norms in seven of the eight domains and improved significantly from presurgical means in all eight domains (p < 0.05). Before surgery, the operative subjects reported high levels of pain with a Pain Rating Index (PRI) score from the MPQ of 26.6. After surgery, pain was significantly lower with a mean PRI score of 11.7, similar to that of our controls (mean PRI score, 11.2). Regression analysis was used to control for covariate effects on the main study outcomes. Among the operative subjects, benefits from breast reduction were not associated with body weight, bra cup size, or weight of resection, with essentially all patients benefiting from surgery.Breast hypertrophy has a significant impact on women's health status and quality of life as measured by validated and widely used self-report instruments including the SF-36, MPQ, and EuroQol. Pain is a significant symptom in this disease, and both pain and overall health status are markedly improved by breast reduction. In this population, conservative measures such as weight loss, physical therapy, special brassieres, and medications did not provide effective permanent relief of symptoms.

Adult↗

PubMed2002

Presence and activity of nitric oxide synthase isoforms in ischemia-reperfusion-injured flaps.

Nitric oxide is produced from the amino acid L-arginine by nitric oxide synthase, which has three known isoforms: (1) endothelial nitric oxide synthase and (2) brain nitric oxide synthase, both of which are constitutive nitric oxide synthase; and (3) inducible nitric oxide synthase. The authors' hypothesis is that after reperfusion injury, endothelial cell dysfunction leads to disruption of nitric oxide synthase-mediated nitric oxide production and that this may in part explain the deleterious effects of ischemia-reperfusion injury on tissue survival and blood reflow in flaps. An experiment was designed to study the effects of ischemia-reperfusion injury on the bioactivity of all three isoforms of nitric oxide synthase. Buttock skin flaps and latissimus dorsi myocutaneous flaps were elevated in eight pigs. Flaps on one side of the animal were randomized to receive 6 hours of arterial ischemia, whereas flaps on the other side served as controls. At 6 hours of ischemia and at 1, 4, and 18 hours after reflow, tissue biopsy specimens were obtained and were processed for both constitutive nitric oxide synthase and inducible nitric oxide synthase enzyme activity on the basis of the L-citrulline assay. In addition, specimens were processed for Western blot analysis of the three isoforms. The authors' results revealed three key findings: first, there was a statistically significant (p < 0.001) decrease in constitutive nitric oxide synthase activity of ischemia-reperfusion-injured flaps as compared with controls in both skin and muscle for all time intervals measured. Second, Western blot analyses of endothelial nitric oxide synthase and brain nitric oxide synthase showed a significant decrease in the signal intensity in ischemic and reperfused tissue as compared with controls. Third, the inducible nitric oxide synthase isoform's activity and protein remained undetectable in both tissue types for all time points measured. The authors' data demonstrated that following ischemia-reperfusion injury in the pig flap model there was a disruption of constitutive nitric oxide synthase expression and activity, which may lead to decreased nitric oxide production. The significant decrease in nitric oxide synthase activity found in the current study may partly explain the mechanism of tissue damage in flaps subjected to ischemia-reperfusion injury. Knowledge of the kinetics of nitric oxide synthase activity under conditions of ischemia-reperfusion injury has important implications for the choice and timing of delivery of therapeutic agents whose goal is to increase the bioavailability of nitric oxide in reperfused tissue.

Animals↗

PubMed2002

Differing flow patterns between ischemically challenged flap skin and flap skeletal muscle: implications for salvage regimens.

In this study, the authors tested the hypothesis that there is a significant difference in spatial patterns of reflow in skin as opposed to skeletal muscle after an ischemic insult. The authors believe that this pathophysiologic difference between the two flap types has significant implications for flap salvage strategies. Bilateral buttock skin flaps (10 x 18 cm) and latissimus dorsi myocutaneous flaps (10 x 20 cm) were elevated in Landrace pigs (n = 7). Flaps on one side of the animal were randomly assigned to 6 hours of arterial occlusion, with the contralateral side acting as control. At 15 minutes, 1 hour, and 4 hours after reflow, radioactive microspheres (15 microm) were injected into the left ventricle. After 18 hours of reperfusion, skin and muscle viability were estimated by intravenous fluorescein and soaking in nitroblue tetrazolium, respectively. Flow rates in the skin with an ischemia-reperfusion injury were significantly reduced (30 to 53 percent), at all time intervals, compared with controls. The flow rate in the fluorescent skin with ischemia-reperfusion injury of the latissimus dorsi flaps (0.037 ml/min/g at 15 min) was greater than in that of the buttock flaps (0.018 ml/min/g). The muscle flaps with ischemia-reperfusion injury had significantly higher flow rates than control muscle flaps at all time intervals studied (at 1 hour, 0.32 ml/min/g compared with 0.16 ml/min/g, respectively). In flap skeletal muscle, an early hyperemic phase during reperfusion maintains a significant blood flow to all regions, including the area of the flap that is destined for necrosis. In flap skin, however, there is a marked decrease in flow rates. These differences have important implications for the intravascular delivery of therapeutic agents to the damaged portions of the flap. Transdermal drug delivery systems should be explored as an alternative to intravascular regimens for the salvage of flap skin with ischemia-reperfusion injury.

Animals↗

PubMed2002

The effects of the nitric oxide donor SIN-1 on ischemia-reperfused cutaneous and myocutaneous flaps.

Ischemia-reperfusion injury causes tissue damage that leads to a decrease in bioavailability of nitric oxide. The authors hypothesized that an exogenous supply of nitric oxide will have beneficial effects on survival of skin and skeletal muscle subjected to ischemia-reperfusion injury. By using the nitric oxide donor SIN-1 (3-morpholino-sydnonimine) the effects of direct intraarterial infusion of an exogenous source of nitric oxide in reperfused flaps was studied. Bilateral island buttock skin flaps and latissimus dorsi myocutaneous flaps were elevated in eight pigs, for a total of 32 flaps. Flaps were subjected to 6 hours of ischemia followed by 18 hours of reperfusion. Flaps on one side of each animal were randomized to be treated with the nitric oxide donor (treatment group). The contralateral side was treated with an equivalent volume of saline vehicle (infusion control) SIN-1, or saline was administered as a continuous direct intraarterial infusion at the onset of reperfusion and continued during the observation period. Outcomes measured were tissue neutrophil accumulation by using myeloperoxidase assay and tissue survival (intravenous fluorescein and nitroblue tetrazolium for skin and muscle, respectively). In both skin and myocutaneous flaps, SIN-1 treatment caused a significant improvement in survival and a decrease in neutrophil accumulation. Nitric oxide may play an important role in the pathophysiologic process of ischemia-induced reperfusion injury in skin and skeletal muscle. Nitric oxide donors may be a promising family of therapeutic agents for the prevention of ischemia-induced reperfusion injury in cutaneous and myocutaneous flaps.

Animals↗

PubMed2002

Rapid and dynamic regulation of TGF-beta receptors on blood vessels and fibroblasts during ischemia-reperfusion injury.

The pathophysiological mechanisms involved in ischemia-reperfusion injury are poorly understood. Although transforming growth factor (TGF)-beta has been shown to provide protection against ischemia-reperfusion injury in different organ systems, little is known about the regulation of TGF-beta action during this process. Here we analyzed the effect of ischemia and reperfusion on the expression of TGF-beta and its receptors in vivo with a pig skin flap model. Analysis of unoperated skin, nonischemic control flap, ischemic flap, and reperfused flap by immunohistochemistry indicates that ischemia and reperfusion result in rapid and dynamic regulation of type I, II, and III TGF-beta receptors and TGF-beta1 in a cell type-specific manner. Furthermore, hypoxia upregulates type II TGF-beta receptor mRNA in skin fibroblasts in culture. Together, our results reveal that TGF-beta receptors and TGF-beta1 are markedly increased under acute ischemic conditions in the blood vessels and fibroblasts of the skin. We conclude that TGF-beta action is enhanced under ischemic conditions and that it may represent an adaptive response to ischemic injury. The augmented TGF-beta responsiveness may be a critical determinant of the protective effect of TGF-beta during ischemia-reperfusion injury.

Activin Receptors, Type I↗

PubMedDate not supplied

Reduction mammaplasty: defining medical necessity.

The authors evaluated existing and new criteria for defining the medical necessity for breast reduction surgery. Two cohorts of women (those requesting breast reduction surgery [N = 266] and a group of controls [N = 184]) completed a questionnaire including breast-specific symptom severity, the Short Form 36, the EuroQol, the McGill Pain Questionnaire, and the Multidimensional Body Self Relations Questionnaire. To evaluate prediction validity, the most widely accepted decision criteria and a new definition of medical necessity were applied to the data set to determine whether women meeting the definition had more favorable outcomes than those who did not as measured by validated self-report instruments. For existing criteria, women not meeting and meeting the criterion gained equal benefit from surgery. Women meeting the new definition (> or = 2 of 7 physical symptoms all or most of the time) had significantly greater improvement scores on 4 of the 5 health burden measures compared to women not meeting this definition. The authors conclude that medical necessity for breast reduction surgery is better defined by self-report of symptoms than by existing criteria.

Adult↗