Search PubMed⌕ Search

Biomedical subjects

M Miller

Publications and source records attributed to M Miller.

At least 1,045 records · Page 58Linked to original sources

Hyperthermia-induced seizures in rat pups with preexisting ischemic brain injury.

To investigate the mechanism(s) relating perinatal brain injury to increased seizure sensitivity in the developmental age period, we studied hyperthermia-induced seizures in rat pups with a preexisting unilateral ischemic cerebral injury. At 2 days of age, the pups underwent a carotid artery ligation followed by 20 min of anoxia. By light microscopy, there were no pathologic changes in the postischemic cerebral cortex at 5, 10, or 20 days of age. Seizures were induced by hyperthermia at 5, 10, 15, or 20 days of age. Seizure temperature thresholds increased with maturation in both postischemic and control animals. Temperature thresholds for behavioral seizures were significantly lower at 10, 15, and 20 days in postischemic pups, compared with control animals. By EEG criteria, seizure thresholds also were lower at 10 and 15 days in the postischemic pups compared with control animals. Preictal EEG slowing appeared at the same temperature in experimental and control animals at all ages. We conclude that the rat pup is an appropriate model for the study of enhanced epileptogenesis in the presence of a perinatal ischemic encephalopathy.

Animals↗

Effect of interictal epileptiform discharges on nocturnal plasma prolactin concentrations in epileptic patients with complex partial seizures.

To investigate the effect of interictal epileptiform discharges (IEDs) on plasma prolactin (PRL) level, we studied 18 epileptic patients with complex partial seizures (CPS) who did not experience clinical or subclinical ictal events during all-night monitoring with polygraphic recording and video imaging. The density of IEDs peaked during non-REM stages and was significantly reduced during REM stage. Mean plasma PRL concentrations in epileptic patients, when sampled at 30-min intervals, showed a moderate but significant elevation during non-REM (p less than 0.001) and awake stages (p less than 0.005), but not during REM stage, when compared with 10 nonepileptic control subjects studied in a similar fashion. The data obtained in this physiologically controlled environment indicate that the cumulative effect of IEDs may modify PRL regulatory mechanisms, resulting in a modest elevation of plasma concentrations independent of ictal discharges.

Adult↗

Differential response of growth hormone, cortisol, and prolactin to seizures and to stress.

Plasma concentrations of growth hormone (GH), cortisol, and prolactin (PRL), following a spontaneous generalized seizure in epileptic men were compared with similar measurements made in nonepileptic, stressed men to determine the role of stress in the hormonal response to seizures. Nonepileptic, nonstressed men served as control subjects. GH concentrations increased significantly within 60 min postictally, and as expected, so did cortisol and PRL. A subgroup of alcoholic patients exhibited a smaller GH response to seizures. Stressed patients had significantly less elevated cortisol and PRL plasma values, but no rise of GH. The data suggest that neurogenic stimuli responsible for the postictal release of GH, cortisol, and PRL are, at least in part, independent of stress mechanisms and that GH response is blunted in alcoholic patients.

Adult↗

Rapid recovery of octogenarians following coronary artery bypass grafting.

BACKGROUND: Rapid recovery protocols for coronary artery bypass grafting (CABG) have resulted in major decreases in postoperative hospital length of stay (LOS) when applied to younger patients undergoing elective procedures. However, the effectiveness of rapid recovery protocols when applied to octogenarians has not been thoroughly studied. METHODS: Thirty-seven consecutive octogenarians underwent isolated CABG utilizing cardiopulmonary bypass (CPB). A protocol emphasizing preoperative placement of the intra-aortic balloon pump, reduced CPB time, early extubation, perioperative steroids, thyroid hormone, and aggressive postoperative diuresis was used. RESULTS: The 30-day operative mortality for the entire series was 5.4%. Twenty-five patients (71%, group I) were discharged in < 10 days postoperatively (average LOS of 6.3 +/- 1.6 days), while ten patients (29%, group II) were discharged at 10 or more days postoperatively (average LOS of 20.3 +/- 8.0, p < 0.001). Patients in group II were found to have a higher incidence of obesity (50% vs 4%, p < 0.01), symptomatic peripheral vascular disease (60% vs 8%, p < 0.01), and preoperative ambulatory difficulties (50% vs 0%, p < 0.01). The incidence of complications was 31% for the entire series, with no differences between the groups. CONCLUSION: Octogenarians performed well under a rapid recovery protocol, with 71% being discharged in < 10 days postoperatively, while patients with obesity, symptomatic peripheral vascular disease, and ambulatory difficulties rehabilitated more slowly.

Aged↗

Simplified Parsonnet risk scale identifies limits to early patient discharge.

BACKGROUND: Fast-track recovery after coronary artery bypass surgery has influenced patient care positively. Predicting patients who fall off track and require prolonged (> or =7 days) hospitalization remains uncertain. The Parsonnet risk assessment score is effective in predicting length of stay, but is limited by inaccurate subdivision of risk categories. We simplified the Parsonnet risk scale to better identify patients eligible for fast-track recovery. METHOD: The cases of 604 consecutive patients who underwent isolated coronary artery bypass grafting (CABG) using cardiopulmonary bypass (CPB) were reviewed retrospectively. A rapid recovery protocol emphasizing reduced CPB time, preoperative intra-aortic balloon pump (IABP) criteria, and atrial fibrillation prophylaxis was applied to all patients. The five original divisions of the Parsonnet risk scale were reduced to three risk categories: Low (0-10; Group A), Intermediate (11-20; Group B), High (> 20; Group C). Comparisons of progressive risk categories were analyzed to identify predictive factors associated with fast-track outcomes. RESULTS: The thirty-day operative mortality for the entire group was 3.6%. Three clinical features were identified that distinguished risk progression-female gender, reoperative CABG, and increased age. Additionally, the presence of diabetes (p < 0.05), congestive heart failure (p < 0.01), and peripheral vascular disease (p < 0.001) distinguished Groups A and B, while acute myocardial infarction (p < 0.05) influenced outcomes in Group C. Group A (48%) mean risk score 5.9+/-3.2 was compared to Group B (34%) 14.8+/-2.6, which was further compared to Group C (18%) 26.4+/-2.8. The mean length of stay for Group A (5.3+/-4.1 days) was notably less than Group B (6.1+/-4.7 days; p < 0.05); however, both groups responded favorably to fast-track techniques. Group C did not respond comparably (9.2+/-9.2 vs 6.1+/-4.7 days; p < 0.001) and experienced prolonged recovery. The simplified Parsonnet risk scale did not identify differences in operative mortality and revealed only pneumonia (p < 0.05) and atrial fibrillation (p < 0.01) to be greater in Group C. As risk increased, significantly less revascularization was performed (Group A 3.6+/-1.2 grafts/patient vs Group B 3.3+/-1.2 [p < 0.01]; Group B 3.3+/-1.2 vs Group C 2.5+/-1.0 [p < 0.001]). CONCLUSION: A simplified Parsonnet risk scale (three categories) is an effective tool in identifying factors limiting fast-track recovery. Low- and intermediate-risk patients represent the majority (82%) and respond well to fast-track methods. High-risk patients (18%) are limited by a greater percentage of female patients, reoperative CABG, and the very elderly, resulting in fast-track failure. Strategies to improve recovery in high-risk patients may include evolving off-pump techniques.

Aged↗

Nursing assessment of patients with non-acute wounds.

Accurate and thorough assessment of patients with wounds is essential in order to provide correct treatment. In relation to patients with open, non-acute wounds, the areas that need assessing include general health and specific underlying disease process, care being given and local wound environment. This article outlines specific details of the assessment process. It includes a breakdown of factors affecting healing, a discussion of the importance of diagnosis of cause, an outline of factors within care provision that may have a negative effect on healing, and areas relevant to the wound itself that should be assessed.

Chronic Disease↗

Environmental correlates of adolescent substance use and misuse: implications for prevention programs.

The research in the areas of peer, family and community environmental effects on adolescent substance use and misuse clearly and consistently shows that peer substance use behavior is the primary predictor of adolescent alcohol use. Peer norms, however, are more important in the prediction of adolescent alcohol misuse. Parental norms and monitoring are secondary to the peer variables, but still of significance in the prediction of adolescent alcohol use and misuse. The intrapersonal construct of susceptibility to peer pressure is as important as the peer and parent variables in the prediction of both alcohol use and misuse in adolescence.

Adolescent↗

Defining home health care nursing: implications for continuing nursing education.

The purpose of this qualitative interpretivist study was to analyze and articulate the characteristics of nursing practice in the home health care context. Researchers sought to describe expert home health care nursing practice and how it developed. Twenty-one nurses, at various stages of practice development, were asked to write three clinical narratives describing their home health care practice. Data were analyzed to elicit themes and characteristics of nursing practice in the home health care context. Findings indicate that in the context of home health care, expert nursing practice develops along a continuum, until nurses can integrate physiological data with environmental and family data to provide seamless, intuitive, and highly complex nursing care. The results of this research can assist continuing education and staff development providers as they develop educational programs designed to facilitate professional development of new graduates and newly employed nurses in home health care.

Community Health Nursing↗

The relationship between soft tissue anomalies around the orbit and globe and astigmatic refractive errors: a preliminary report.

Corneoscleral limbal masses were created in ten rabbit eyes and upper eyelid colobomas were produced in an additional ten eyes. The resultant changes in corneal curvature were recorded over a one-month period using streak retinoscopy and photokeratometry. By these methods, we have determined that forces at or near the corneoscleral limbus can produce changes in the corneal curvature that lead to refractive errors primarily of the astigmatic variety. There is a shift of the axis of astigmatism towards the meridian 90 degrees away from the external force or an increase of astigmatism along the meridian where the force was exerted. In this study, corneal curvature changed significantly in the coloboma and epibulbar mass groups when compared to the control group. This study supported a causal relationship between soft tissue anomalies and astigmatic refractive errors seen clinically in certain syndromes, such as Goldenhar and mandibulo-facial dysostosis. These findings suggest that patients observed with periorbital soft tissue defects may be at risk for the development of unilateral anisometropic refractive errors and secondary amblyopia. Recognition of this entity is essential in order that adequate therapy can be instituted at an early age.

Animals↗

Fetal alcohol syndrome.

Significant alcohol ingestion during pregnancy can cause a spectrum of malformation of various degrees of severity in offspring. The full expression of "fetal alcohol syndrome" includes reduced growth, facial anomalies, and mental retardation. Affected infants are usually of near-term gestation, but small in weight and length. They continue to exhibit decreased growth postnatally. Mental retardation appears to be related to the degree of dysmorphic severity of appearance. It is primarily caused by central nervous system pathology rather than social environment. The most prevalent ophthalmologic finding in our series of a short horizontal palpebral fissure appears to be due primarily to a marked increased in intercanthal distances between the medial canthi (primary telecanthus) and to less extent mild displacement of the lateral canthi. Ptosis, often asymmetric, was noted in a number of patients. Comitant convergent strabismus was present in about 50% of our cases; a few had amblyopia. An important observation was the frequent and often high degree of myopia in these children. Low-incidence anomalies include corneal opacities (Peters anomaly in one), cataract, tortuosity of retinal vessels, and long eyelashes. Our findings plus many observations in the literature establish that children with fetal alcohol syndrome are at considerable risk for a variety of eye problems.

Child↗