Outlook Magazine, Spring 1980

https://digitalcommons.wustl.edu/outlook/1057/thumbnail.jp

Non-contrast Magnetic Resonance Angiography for Evaluation of Peripheral Arterial Disease

Peripheral arterial disease (PAD) is a major cause of morbidity and mortality in the USA with an estimated prevalence of up to 20% in those over 75 years. Vascular disease and kidney impairment frequently coexist; prevalence of moderate to severe renal dysfunction in PAD patients is estimated at 27-36%. Knowledge of location, severity, and extent of PAD is imperative for accurate diagnosis and treatment planning. However, all established imaging modalities that are routinely used for treatment planning are contra-indicated in kidney disease patients. Contrast-enhanced x-ray and CT angiography are unsafe due to exposure to nephrotoxic contrast material and ionizing radiation. Recently, the FDA has also warned against the use of gadolinium-enhanced MRA (Gd-MRA) due to evidence that gadolinium could trigger a life-threatening condition known as nephrogenic systemic fibrosis (NSF) in patients with moderate to severe kidney dysfunction. There is a clinical need to develop vascular imaging techniques that are safe in patients with coexisting PAD and renal insufficiency. The focus of this thesis was the development of a non-contrast alternative to Gd-MRA for imaging of peripheral vessels from renal to pedal arteries with MRI. A new imaging sequence for non-contrast visualization of the abdominal and pelvic arteries was designed, implemented, and validated in a small cohort of PAD patients against Gd-MRA. In addition, an existing fast spin-echo based technique for unenhanced imaging of the lower extremities was optimized for improved performance in a clinical setting

Hysterectomy

This book is intended for the general and family practitioners, as well as for gynecologists, specialists in gynecological surgery, general surgeons, urologists and all other surgical specialists that perform procedures in or around the female pelvis, in addition to intensives and all other specialities and health care professionals who care for women before, during or after hysterectomy. The aim of this book is to review the recent achievements of the research community regarding the field of gynecologic surgery and hysterectomy as well as highlight future directions and where this field is heading. While no single volume can adequately cover the diversity of issues and facets in relation to such a common and important procedure such as hysterectomy, this book will attempt to address the pivotal topics especially in regards to safety, risk management as well as pre- and post-operative care

Health Sciences handbook

2004 handbook for the faculty of Health Science

Health Sciences handbook

2006 handbook for the faculty of Health Science

Optimisation of gestational age estimates in low-income settings

Accurate estimates of gestational age are fundamental to the provision of obstetric care, helping to facilitate appropriate antenatal care schedules and the identification and management of high-risk pregnancies. At a population level, accurate estimates of gestational age are required for the global reporting of obstetric and neonatal outcomes, for example, the rates of pre-term birth, and are a key component of strategies to reduce neonatal morbidity and mortality. Early pregnancy ultrasound is considered the most accurate way to determine gestational age and is undertaken as part of routine care in high-income settings. However, despite the recommendation from the World Health Organisation that all women receive at least one ultrasound prior to 24 weeks’ gestation, this remains unavailable to the majority of women in low-income settings. Instead, gestational age is derived from the last menstrual period or by measurement of the symphysis fundal height, methods known to be considerably less accurate. There are a number of barriers to the widespread provision of ultrasound as part of routine care in low- and middle- income settings, not least the lack of trained practitioners. Although effective, the length and complexity of many previous training programmes has been prohibitive, with practitioners struggling to secure cover for their clinical duties in order to provide or attend training. Furthermore, few initiatives have explored the widespread implementation of these programmes and how they may be sustained within pre-existing healthcare structures. Ultrasound determination of gestational age relies on the assumption that the size of the fetus is consistent with its age and is therefore best performed prior to 14 weeks’ gestation, when natural variation in fetal size is least apparent. Unfortunately, the majority of women in low- and middle- income countries do not seek antenatal care until later and would therefore require dating by different biometric parameters. In high-income settings the gold standard would be a combination of measurements, however there are concerns about the time investment required to develop such skills. The work in this Thesis explores the development of a novel strategy to optimise estimates of gestational age in Malawi, through the development and implementation of a bespoke education package to teach midwives how to date pregnancies using ultrasound measurement of the fetal femur length. A systematic review investigated the previous initiatives that had been undertaken to train practitioners in low- and middle- income countries to determine gestational age using ultrasound, finding major inconsistences in the current provision of ultrasound training and highlighting the need for a more consistent and robust approach. Less than half of the programmes met international recommendations for the delivery of safe and sustainable training, and many had not considered how ultrasound may be integrated into clinical practice thereafter. The evidence synthesised went on to inform the development of a new programme, where it was hypothesised that ultrasound-naive midwives could be taught to date pregnancies using fetal femur length. Pilot work helped to shape and refine the programme, which was delivered by local teams across six sites in Malawi in 2021. All but one midwife completed the course, with all demonstrating significant increases in their knowledge, confidence, and practical skills, achieving the criteria specified for competency within the specified two weeks. Skills were sustained at a 3-month follow up, and of the images submitted for remote image review, over 87% were deemed acceptable. These results suggest that femur length is a sufficiently simple measurement to be taught effectively over a short timescale, making it a potentially viable option for the upscale of ultrasound to date pregnancies in this setting. A mixed methods study, run by the wider collaborative group, evaluated the implementation of ultrasound into routine services, however the work in this Thesis focused more specifically on the provision of the programme itself. Outcomes were reported in the context of an implementation framework, providing valuable insight into factors influencing the longterm sustainability of such endeavours. It is clear this is an important area for ongoing research. In conclusion, this Thesis proposes that measurement of fetal femur length should be considered a potential option for the determination of gestational age in low- and middle- income settings. Not only is it considerably more accurate than the current standard of care, but midwives with no prior experience of ultrasound can be trained to perform these measurements, confidently and competently, after just two weeks of training, a substantially shorter training duration than many previous initiatives. Although many implementation challenges persist, this programme provides a potentially more sustainable means by which to provide a greater number of women more accurate estimates of gestational age

Cerebrovascular Hemodynamics, Postural Stability, Gait Dynamics, and Falls in Older Adults

Injurious falls in community-living older adults are associated with standing up suggesting that cerebral hypoperfusion following a postural transition might be a contributing factor. A large population study has recently indicated that one fifth of older adults do not fully recover BP after standing from a supine posture. The purposes of this thesis were to provide a comprehensive assessment between posture-related cerebral hypoperfusion and impaired postural stability, altered gait and falls in older adults. This thesis measured arterial blood pressure regulation and cerebral tissue oxygenation (tSO2) during orthostatic stressors including 3 different transitions to standing in older adults (n=77, ages 69-100 years, average = 86.6±6.6 years) and 2 different transitions to walking in a sub-group of these older adults (n=27, ages 71-101 years, average = 86.8±5.3 years). Primary results included the finding that, like the altered blood pressure responses, 19.5% of older adults had low tSO2 on standing, and they had poorer postural stability. It was also found that a brief 10-s sitting-pause time improved tSO2 and postural stability when performing a supine-sit-stand. Prospective tracking of older adults for 6-months revealed a trend to an increased likelihood of a future fall in those who had the greatest drop in tSO2 on standing. Older adults with low tSO2 (≤60%) during walking had compromised gait dynamics (increased step-step variability). Although gait speed was not directly related to reduced tSO2, the increased mean gait cycle time and stance time associated with changes in OxHb of the older adults with low tSO2 were significantly associated with reduced gait speed. Increased vascular stiffness was associated with lower CBF and altered cerebrovascular hemodynamics while walking as well as lower gait speed. Collectively, the findings from these two investigations support a relationship between cerebral hypoperfusion induced by transitions from supine to upright posture and compromised standing and walking stability with consequences for increased fall risk