Quantification of Left Ventricular Twisting Mechanics by Velocity Vector Imaging in an Animal Model of Pericardial Adhesions

Diagnosis of constrictive pericarditis remains clinically challenging. Untwisting of the left ventricle (LV) is essential for normal LV diastolic function. Echocardiography is able to measure LV twisting mechanics. We designed an animal model of constrictive pericarditis to determine how pericardial-epicardial adhesions impair LV twisting mechanics. In eight open-chest pigs, the heart was exposed while preserving the pericardium. We simulated early constrictive pericarditis by pericardial constriction and patchy adhesions induced with instant glue and pericardial-epicardial stitches. Using Velocity Vector Imaging™ (VVI), LV magnitudes of twisting and untwisting were measured along with hemodynamic data at baseline and after the experimental intervention. Significant decreases in end-diastolic volume, ejection fraction, stroke volume, and late diastolic filling velocity reflected the effects of the pericardial adhesions. Magnitude of LV untwisting rate decreased from –80 ± 23°/s to –26 ± 10 °/s (p = 0.0009). LV twisting rate dropped from 78 ± 20°/s to 40 ± 8°/s (p = 0.0039) and LV twist magnitude decreased from 9 ± 2° to 5 ± 2 ° (p = 0.0081). Patchy pericardial adhesions are associated with reductions in LV untwisting rate and twisting magnitude, consistent with a negative impact of constrictive pericarditis on systolic and diastolic function. Impairments in LV twisting mechanics may have a diagnostic role in the detection of early stages of constrictive pericarditis. (E-mail: belohlavek.marek@mayo.edu)     

The prevalence and characteristics of Streptococcus pneumoniae isolates expressing serotypes 6C and 6D in Hong Kong prior to the introduction of the 7-valent pneumococcal conjugate vaccine

A study was conducted to determine the prevalence of the 2 newly described types, 6C and 6D, among pneumococcal isolates collected in Hong Kong before availability of the 7-valent pneumococcal conjugate vaccine. A total of 154 serogroup 6 isolates obtained from nasopharynx (n = 106), blood (n = 22), respiratory (n = 24), and cerebrospinal fluid (CSF) (n = 2) during 1995 to 2001 were analyzed by polymerase chain reaction typing. Five nasopharyngeal and 2 sputum isolates were found to belong to 6C and 6D, respectively. The isolates were genetically diverse, but one 6C and two 6D isolates exhibited some clonal relationship. Phylogenetic analysis of the wchA-wciN(β)-wciO nucleotide sequences showed that the Hong Kong 6C/6D isolates had 2 allelic profiles, which were more closely related to 6C/6D isolates from Fijian and Korea than were those from Brazil and the United States. However, all of the wciP gene sequences for both Hong Kong and non-Hong Kong isolates clustered together: 6C isolates with the wciP-9 allele and 6D isolates with the wciP-5 allele. In conclusion, the prevalence of the 2 newly described serotypes was low before the era of the pneumococcal conjugate vaccine. Nonetheless, results from the molecular studies indicated that the evolution of the capsular genes have involved complex pathways.     

Influences on Decision Making Among Primiparous Women Choosing Elective Caesarean Section in the Absence of Medical Indications: Findings From a Qualitative Investigation

ObjectivePatient-initiated elective Caesarean section (PIECS) is increasingly prevalent and is emerging as an urgent issue for individual maternity practitioners, hospitals, and policy makers, as well as for maternity patients. This qualitative study sought to explore women’s experiences of the decision-making process leading to elective operative delivery without medical indication.MethodsWe conducted 17 exploratory qualitative in-depth interviews with primiparous women who had undergone a patient-initiated elective Caesarean section in the absence of any medical indication. The study took place in five hospitals (three urban, two semi-rural) in British Columbia.ResultsThe findings revealed three themes within the process of women deciding to have a Caesarean section: the reasons for their decision, the qualities of the decision-making process, and the social context in which the decision was made. The factors that influenced a patient-initiated request for delivery by Caesarean section in participants in this study were diverse, culturally dependent, and reflective of varying degrees of emotional and evidence-based influences.ConclusionPIECS is a rare but socially significant phenomenon. The a priori decision making of some women choosing PIECS does not follow the usual diagnosis-intervention trajectory, and the care provider may have to work in reverse to ensure that the patient fully understands the risks and benefits of her decision subsequent to the decision having been made, while still ensuring patient autonomy. Results from this study provide a context for a woman’s request for an elective Caesarean section without medical indication, which may contribute to a more efficacious informed consent process.     

International adoption families: a unique health care journey

The purpose of this study was to identify and describe the health care experiences of families with an internationally adopted child. Content analysis of data from 107 adoptive parents was used to identify themes that characterized health care experiences of the families. Four themes were identified: a) Coming home: Like a lobster thrown into a boiling pot; b) Vigilance: Is my child healthy today? Will my child be healthy tomorrow?; c) Unique health care needs of international adoption families: We are different; and d) Importance of support by health care providers: Do they know or care? Health care providers need to be aware of the unique experiences of the increasing number of international adoption families. The themes identified provide insight into the health care experiences of international adoption families and the crucial role of health care providers in helping international adoption families feel supported on their journey.     

Understanding clinical expertise: Nurse education,experience, and the hospital context

Clinical nursing expertise is central to quality patient care. Research on factors that contribute to expertise has focused largely on individual nurse characteristics to the exclusion of contextual factors. To address this, we examined effects of hospital contextual factors and individual nurse education and experience on clinical nursing expertise in a cross‐sectional analysis of data from 8,611 registered nurses. In a generalized ordered logistic regression analysis, the composition of the hospital staff, particularly the proportion of nurses with at least a bachelor of science in nursing degree, was associated with significantly greater odds of a nurse reporting a more advanced expertise level. Our findings suggest that, controlling for individual characteristics, the hospital context significantly influences clinical nursing expertise. © 2010 Wiley Periodicals, Inc. Res Nurs Health 33:276–287, 2010     

Patient falls: Association with hospital Magnet status and nursing unit staffing

The relationships between hospital Magnet® status, nursing unit staffing, and patient falls were examined in a cross‐sectional study using 2004 National Database of Nursing Quality Indicators (NDNQI®) data from 5,388 units in 108 Magnet and 528 non‐Magnet hospitals. In multivariate models, the fall rate was 5% lower in Magnet than non‐Magnet hospitals. An additional registered nurse (RN) hour per patient day was associated with a 3% lower fall rate in ICUs. An additional licensed practical nurse (LPN) or nursing assistant (NA) hour was associated with a 2–4% higher fall rate in non‐ICUs. Patient safety may be improved by creating environments consistent with Magnet hospital standards. © 2010 Wiley Periodicals, Inc. Res Nurs Health 33:413–425, 2010