4. Electronic Theses and Dissertations (ETDs) - Faculties submissions
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Item Characterising skeletopathy in an animal model of type 2 diabetes(University of the Witwatersrand, Johannesburg, 2022-11) Dlamini, Gcwalisile Frances; Ndou, RobertType two diabetes (T2D) is a chronic, progressive heterogonous syndrome with a genetic and environmental origin. It is now recognized as an epidemic with a high morbidity and mortality rate. The endocrinology of type 2 diabetes (T2D) and its predisposing factors have been studied extensively, while diabetic skeletopathy has received negligible research. Previous studies report that fractures in T2D vary with specific sub regions in bones, therefore prompting our study to focus mainly on the femoral head and neck as well as the humerus head. Femoral neck fractures are the commonest, followed by the proximal femur, distal radius and proximal humerus. Susceptibility to fracture is a sequelae of poor bone remodeling. Poor bone remodeling is established at molecular and cellular levels. It depends on the activity of osteoblasts, osteocytes and osteoclasts, which are under the influence of TGF-β1, a pro-osteogenic cytokine, together with BMP3, an anti-osteogenic cytokine. T2D induced bone marrow adipocity and the accumulation of AGEs in cortical bone have also been implicated in increasing susceptibility to fracture. It is still unclear how T2D affects molecular and cellular elements that culminate in weaker bones observed in diabetic patients. In addition, it is debatable if T2D affects the skeleton at disease onset or later in the disease. Therefore, this study aimed to characterize T2D induced skeletopathy and related it to age, in the Zucker Diabetic Sprague Dawley (ZDSD) rat, using the femur and humerus. This study initially confirmed the diabetic state by monitoring animal weights, fasting blood glucose levels, and fasting oral glucose tolerance tests (OGTTs) every fortnight. Then triglyceride levels and quantified serum levels of osteoregulatory hormones such as insulin and osteocalcin were monitored. To assess oxidative stress, Malondialdehyde (MDA) serum levels were also determined by ELISA. Once diabetes was successfully induced, rats were grouped according to strain and age at termination. Termination age was at 20 weeks and 28 weeks . The Sprague Dawley (SD) rats were the controls, while the Zucker Diabetic Sprague Dawley rats (ZDSD) were the experimental groups. These were designated as SD20WK (n=8) and ZDSD20WK (n=7) respectively. Another batch was designated as SD28WK (n=8), and ZDSD (n=15) that were terminated at 28 weeks of age. The latter were further divided into moderate diabetes (ZDSD28WK-MOD) (n=9) and severe diabetes (ZDSD28WK-SVD) groups (n=6). Bilateral humeri and femora were harvested then fixed in 10% buffered formalin. Right proximal femora and humeri were scanned using a 3D-μCT scanner (Nikon XTH 225L) to analyse trabecular morphometric parameters, cortical bone area and medullary canal area. Biomechanical strength was analyzed by three point bending tests using a universal tensile tester. Left proximal femora and humeri were processed for histology. Some sections were stained with Haematoxylin and Eosin (H&E) to assess normal histologic morphology and adipocyte quantification. Remnant sections were immunolabelled using the anti-TRAP and anti-ALP antibodies for osteocyte and osteoblast quantification respectively, to assess osteolysis and osteogenesis. Immunolocalization of AGEs, TGF-β1 and BMP3 was also conducted to investigate their role in diabetic skeletopathy. We found that diabetes affected osteoblastogenesis as measured by ALP positive cells and bone marrow adipocytes. TRAP positive osteocytes numbers were increased in the presence of T2D, suggesting an increased osteolysis. There was reduced TGFB1 expression with increased BMP3 expression. The number of AGEs immuno-positive cells as well as its extracellular expression was increased. Our finding suggest that osteoblast and osteocyte numbers are regulated by TGFβ1 and BMP3 in both bones, under the influence of AGEs. Our findings from osteometry, 3-point bending tests and Micro CT support that diabetes weakens bone. The diabetic effect results in lighter, shorter hollow bones that perform poorly under loading, as well as exhibit unfavourable trabeculae microarchitecture. Our findings confirm that T2D causes increased fragility in the proximal femur and humerus as well the mid-diaphysis. These perturbations occur early and late in the disease, and they are also exacerbated by the presence of hyperglycemia. We conclude that the ZDSD rat can be used as a translational model for diabetic skeletopathy at cellular and molecular level, and it can be extrapolated to humans after consideration of other factors like, basal metabolism, age, sex and skeletal loading patterns. We recommend optimal control of blood glucose levels at all stages of the disease to reduce the incidence of fractures in diabetic patients.Item Support programme for healthcare professionals involved in adverse events in public hospitals in Gauteng(University of the Witwatersrand, Johannesburg, 2022-12) Nkosi, Elizabeth Malefu; Armstrong, Sue; Nkosi-Mafutha, NokuthulaBackground: Adverse events in the healthcare services result not only in administrative and financial costs to the healthcare institution, but also in personal costs to the patients and their families, who are often angry, disappointed, and sad. In the current litigious healthcare climate, relatives, supported by legal advisors, often seek redress as a way of managing their distress. Thus, patients are not the only victims of adverse events. The healthcare professionals that are directly involved often shoulder the blame, sometimes fairly, and sometimes unfairly, while they too need psychological support. A culture of blame in institutions can lead to healthcare professionals involved in an adverse event being marginalised, feeling personally responsible for the event and that they have failed the patient, and they are left to suffer in silence. While anecdotal evidence exists that such stress may lead to negative coping mechanisms, the researcher has not identified any research study conducted in public hospitals in Gauteng, South Africa that identifies and describes the influence that the involvement in an adverse event has on healthcare professionals. Such evidence is required to develop a support programme that could assist healthcare professionals who have been directly involved in adverse events, to minimise the concomitant stress, and to enable these professionals to continue to provide quality care after such an event. Aim: The purpose of this study was to develop, describe, and evaluate the implementation of a support programme for healthcare professionals involved in adverse events in public hospitals. Methodology: A sequential, multimethod research design was used. The study was conducted in five phases. Phase 1 consisted of a scoping review of the international literature that focused on the experiences of the nurses and doctors. The question asked in the scoping review was: What is known from existing literature about the support programmes for healthcare professionals involved in adverse events in clinical settings, and are they effective? Phase 2 involved storytelling that explored the impact of adverse events on involved healthcare professionals. Smith and Liehr’s (2005) methodology was used, that is, healthcare professionals who were directly involved in or affected by one or more adverse events in the public hospitals in Gauteng narrated their experiences. Phase 3 used semi-structured interviews with the managers to explore how best to support health professionals involved in adverse events. Phase 4 involved developing a support programme according to the Wits Trauma Model developed by Eagle, Friedman and Shumkler, from the Psychology Department of the University of the Witwatersrand, in 1993 (Eagle, 2000). Phase 5 focused on confirming and validating the programme to support healthcare professionals involved in adverse events in public hospitals. This phase was subdivided into two sections: Phase 5.1 comprised the Delphi group; and Phase 5.2 comprised the Focus group. In the first round involving the Delphi group, technical data was collected from the experts who validated the programme by means of the survey that was distributed on Research Electronic Data Capture. Concerns arising out of the first round with the Delphi group and that required attention were addressed during the Focus group discussion. Results: Hospitals were not aware of the magnitude of second victimhood and hence the delay in reviewing the structures in place to provide support to those involved. Just (fair) culture principles were not adhered to as there were no guidelines for their implementation, hence the second victims were left traumatised and in isolation following their involvement in adverse events, and they experienced blaming by management instead of being provided with much needed support. Limitations: The limitations to the study include the small sample size during the data collection phases, due to the Coronavirus disease of 2019 pandemic. Due to the restrictions that were implemented it was not possible to contact all the staff as they had been relocated to other healthcare facilities, were absent, or had resigned. Those who were snowballed were no longer at the facilities where they were originally identified, and therefore the researcher was unable to capture their experiences. Objectivity was not maintained as the documents for the Delphi group were hand-delivered, participants were able to identify the researcher, and hence the social desirability concern. The face-to-face encounters made adherence to anonymity impossible. The model components were not practical in terms of the developed programme. Round two of the Delphi group could not be scheduled, thus challenging the study model. Conclusion: The impact of adverse events on healthcare professionals remains an underestimated health concern. Experiences are magnified by unsupportive work environments, and are evident in increased hostility, blaming, fear of punishment, and reputational harm. The second victims require support to enable them to recover and learn from their involvement. The programme was developed, which included the summarised structure and the detailed process for implementation by hospital management on how to manage the adverse events in public hospitals in Gauteng.Item Could Not Sing in the Dead Heat: Liner Notes Under the Sun(University of the Witwatersrand, Johannesburg, 2022) Ramphalile, Molemo Karabo; Schuhmann, AntjeOn the one hand we place blackness as a historical if inconsistent category inextricable with morbidity, disfavour, depravity, mystery, wretchedness, penumbra, opacity or absence of light, and the abyssal – in both secular and religious metaphysical symbolism. On the other hand we place space as a historical and physical category denoting area, range, clearance, scope, volume, expanse, lacunae, aperture, margin, and in its instance as verb – opening, arranging, ordering, placing, separating, and locating; which in cosmography, geography and cartography finds its varied imaginative and applied interpretation. We coalesce what is in both hands in order to envisage how blackness persistently becomes and comes to be the extractable property of sub-Saharan Africans. Through various ontological-cosmographic- geographic designations such as Torrid Zone, ‘land of the blacks’ or even terra nullius, we encounter visualisations of a territory and expanse that is always either completely devoid of people or inadequately peopled, that is, the territory whence blackness as inextricably embodied (or fleshened) exists and is cultivated. Blackness: not only does it determine our modes of being, or non-being, in this world, but for us in this study, it is also an experiential, experimental and analytical lens permitting the suggestion and scribing of historical narratives and discourses that centre the inveterate decentring of blacks. In the tradition of liner notes, this study is written in a performative relation to the subject or object at hand; there under the sun, in the dead heat.Item Voiding cystourethrography in the renal pre-transplantation workup: an essential investigation?(University of the Witwatersrand, Johannesburg, 2022-10) Sofianos, Zelia; Rajkumar, Leisha; Lucas, SusanINTRODUCTION: Due to resource constraints in the South African public healthcare sector, patients with End-Stage Renal Disease (ESRD) are eligible for renal replacement therapy only if they are also found to be eligible for renal transplant. AIM: The aim of this study is to document Voiding Cystourethrogram (VCUG) findings in potential renal transplant candidates to assess the contribution of the VCUG as a standard investigation in the renal transplant workup. METHODS: Of the patients who underwent VCUG in Klerksdorp/Tshepong Hospital Complex (North West province, South Africa) from 1 January 2019 to 31 March 2020, 85 patients were included in the study and their VCUG findings retrospectively analysed. RESULTS: The mean age was 40.0 years (range 21-62 years), with males constituting 57.7% of patients and females 42.3%. Lower urinary tract abnormalities were identified in 24.7% of patients, some of whom had more than one abnormality. Of the total abnormalities, VUR (vesicoureteral reflux) accounted for 15.3%, bladder diverticula for 5.9%, urethral strictures for 3.5% and a significant post-void residual volume for 4.7%. No comorbidities were found to have a statistically significant association with the presence of VCUG abnormalities. CONCLUSIONS: To ensure that patients with End-Stage Renal Disease are adequately prepared for renal dialysis and potential renal transplant, and that their comorbidities and lower urinary tract are optimised should abnormalities be identified on VCUG, the VCUG remains an essential investigation in the renal transplant workup.Item Emergency Department Turnover Intention: Are Job Satisfaction and Burnout Really the Main Culprits?(University of the Witwatersrand, Johannesburg, 2022-11) Jonker, Yvonne Denise; Motara, Feroza; Moolla, MuhammedBackground: Patient presentations to emergency departments (ED) keep increasing. High staff turnover is detrimental to the healthcare worker (HCW), the organisation and the patient. While high levels of burnout (BO) and low levels of job satisfaction (JS) lead to a higher intention to leave (ItL), there are other factors affecting the ItL that need to be evaluated. Objective: To determine the levels of BO, JS and ItL, including when, where and why HCWs want to leave in order to find ways to reduce staff turnover. Methods: This was a prospective observational cross-sectional study conducted in two tertiary-level EDs in Johannesburg, South Africa namely Chris Hani Baragwanath Academic Hospital (CHBAH) and Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). Doctors and nurses were invited to complete self-administered questionnaires between 24 November 2020 and 24 March 2021. After analysis the results for doctors and nurses and the two units were compared in order to bring understanding to the different facets affecting staff turnover. Results: A total of 78 respondents (66% of doctors and 58% of nurses) completed questionnaires and were included for analysis. According to the Copenhagen Burnout Inventory 79% of CHBAH doctors, 62% of CHBAH nurses, 79% of CMJAH doctors and 84% of CMJAH nurses suffered from severe personal burnout, while 68% of CHBAH doctors, 62% of CHBAH nurses, 95% of CMJAH doctors and 68% of CMJAH nurses suffered from severe work-related BO and 42% for CHBAH doctors, 24% of CHBAH nurses, 47% of CMJAH doctors and 32% of CMJAH nurses had severe patient-related burnout. Doctors had significantly higher patient-related burnout (p=0.012). JS was average for all staff but nurses were significantly less satisfied (p=0.003). While 42% of staff intended to leave within a year, of which half wanted to leave as soon as possible, a total of 73 % wanted to leave within 5 years. CMJAH staff had higher levels of BO, lower levels of JS and higher levels of ItL. Higher levels of BO and lower levels of JS increased the ItL. The main reasons for leaving were career-related. Conclusion: Burnout levels were higher than similar populations before and during the Covid-19 pandemic, while job satisfaction levels were average. Although burnout and job satisfaction affected intention to leave, the main reasons for wanting to leave were career-related indicating that even when work conditions and burnout could be addressed successfully, the turnover of staff in tertiary level EDs may remain high.Item Analysis of Orthopaedic Injuries in Polytrauma Patients at Charlotte Maxeke Johannesburg Academic Hospital(University of the Witwatersrand, Johannesburg, 2022) Laney, Wezley; Naicker, Dharshen; Milner, BrendaBackground: Traumatic injuries represent a significant burden globally, accounting for ten percent of the global burden of disease. In South Africa we commonly see patients who have sustained major trauma, often with multiple injuries. This significant burden of trauma necessitates the demand for rapid diagnostic assessment of injuries for appropriate therapeutic intervention. A whole body computed tomography (CT pan scan) allows for a rapid multisystem injury diagnosis of trauma patients. There is a scarcity of literature evaluating the extent of orthopaedic injuries in polytrauma patients. Study Aim: The aim of the study was to evaluate the local epidemiology of orthopaedic injuries in polytrauma patients who have undergone a CT pan scan. Methods: A retrospective, observational analysis, based at Charlotte Maxeke Johannesburg Academic Hospital, was done of polytrauma patients who underwent a CT pan scan, during a 2-year period from 01/01/2018 – 31/12/2019. A database was compiled by accessing the picture archiving and communication system for CT reports. The qualitative data was reported using frequencies and percentages. Categorical variables were analysed using the Chi-squared test (or Fisher’s exact test). Results: Over the two-year study period a total of 296 polytrauma patients had a reported CT pan scan performed. Of these, 85% were male and 15% were female with a median age of 33 years. The most common mechanism of injury was motor vehicle accidents (33.1%). The prevalence of orthopaedic injuries in polytrauma patients was 53.3%. A total of 1012 injuries were found. One hundred and ninety-six (196) spinal fractures were detected; a total of 137 pelvic/sacral fractures, 101 long bone fractures with 75% lower limbs and 25% were upper limb fractures. The most common non-orthopaedic injury sustained was a chest injury. The most common combination of orthopaedic and non-orthopaedic injuries identified in the study was a chest injury with an associated pelvic/sacral fracture secondary to a PVA. Interpersonal and intentional injuries were significantly associated with a higher risk of thoracic spine fractures (RR 1.8, CI 1.1-2.9). Road traffic accidents were significantly associated with a higher risk of scapular/clavicular fractures (RR 2.0, CI 1.2-3.5) and a higher risk of tibial/fibula fractures (RR 3.5, CI 1.2-10.3) Conclusion: The majority of polytrauma patients seen at CMJAH were young males, who sustained injuries during road traffic accidents. Fractures accounted for 94% of all orthopaedic injuries. The most common orthopaedic injury detected in our cohort, overall, was a spinal fracture, most commonly involving the cervical spine. A patient involved in a road traffic accident is 3.5 times more likely to sustain a tibia/fibular fracture as opposed to any other fracture. The most common non-orthopaedic injury sustained was a chest injury. Importantly, 1 in 4 of these patients sustained an associated cervical spine injury and 1 in 3 a pelvic injury, similarly with head injuries. The most common combination of injuries is a chest injury with an associated pelvic/sacral fracture secondary to a pedestrian vehicle accident. The findings highlight the significant burden of orthopaedic injuries in polytrauma patients. In addition, the findings of this study, highlight injury patterns that should be anticipated in polytrauma patients.Item Adherence to the Standard Treatment Guidelines in managing patients with hypertension at Chiawelo Community Health Centre, Gauteng, South Africa(University of the Witwatersrand, Johannesburg, 2022-04) Dawduth, Nikkeeta; Torlutter, MicheleBackground: Hypertension is a highly prevalent chronic disease, causing significant morbidity and mortality and is poorly managed and controlled in primary care, with only 24.5 to 56% of patients being controlled. Aim: The aim of the study was to determine health care worker adherence to the Standard Treatment Guidelines in managing hypertensive patients in primary care. Methods: The study was conducted at Chiawelo Community Practice Johannesburg. A retrospective file review was done on 261 hypertensive patients and information extracted to determine whether health care workers performed correct baseline tests at diagnosis; correct investigations were done on ongoing basis; lifestyle modification was addressed; and correct pharmacological therapy was prescribed and titrated. Data analysis included descriptive statistics and bivariate analysis. Results: A total of 77% of participants were female and 23% were male of which 80.5% participants had co-morbidities. Patients were treated by a doctor in 97% of cases; 84.3% by clinical associate, and 0.6% by a nurse only over time. Baseline findings recorded in the file at diagnosis were: weight 65.9%, height 73.2%, potassium 32.2%, BMI 50.2%, abdominal circumference 51.7%, and urine dipsticks 47.9%. Vitals and investigations recorded in the file: BP 99.6%, weight 19.5%, blood glucose 86.6%, creatinine 95.4%, eGFR 94.3% and urine protein 3.4%. Lifestyle modification was recorded for 23.7% and medication adherence was checked and recorded for 36.4% of patients. The correct antihypertensive medications were prescribed in 96.5% of patients but titrated correctly in only 73.5% of patients. 52.8% of patients were controlled on treatment. Conclusion: Adherence to guidelines by health care workers was suboptimal and several aspects of care warrants quality improvement processes.Item Clinical course and outcomes of confirmed and suspected Pneumocystis jirovecii pneumonia in Sowetan children living with HIV(University of the Witwatersrand, Johannesburg, 2022-07) Darji, Mohiniben; Moore, David PaulIntroduction: Pneumocystis jirovecii is an important opportunistic pathogen in children living with HIV (CLWH), responsible for the majority of community acquired pneumonia (CAP) admissions in infancy. There is scanty evidence on long-term survival rates in children hospitalised with P. jirovecii pneumonia (PCP), especially in settings with a high burden of paediatric HIV. Methods: Admissions to general paediatric wards at Chris Hani Baragwanath Academic Hospital over the period 01 January 2011 to 31 December 2019 were assessed for a discharge diagnosis of PCP. PCP was classified as being confirmed or presumed, based on laboratory criteria. Only CLWH were included in the study. Results: Over the 9-year study period, 390 cases of PCP were diagnosed, of which 297 (76.2%) were in CLWH. The majority of the PCP episodes were presumed (262/297, 88.2%). Sixteen children had recurrent PCP admissions. There was no difference between the median age of children at admission with confirmed PCP or presumed PCP (4.07 months vs 3.66 months; P=0.590). Children with presumed PCP were significantly underweight (weight-for-age Z-score -2.88 vs -1.74; P<0.001) and wasted (weight-for-length Z-score -1.15 vs -0.38; P=0.039) compared to those with confirmed PCP. Children with presumed PCP had a higher prevalence of confirmed pulmonary tuberculosis (7/18 (38.9%) vs 1/35 (2.9%); P=0.002). The majority (56.1%) of patients were initiated on antiretroviral therapy (ART) one week after the PCP admission episode. Of 58 PCP episodes in which data on mechanical ventilation was available, 18 (31.0%) were ventilated. Case fatality was 44.4% in ventilated patients, and the overall in-hospital case fatality was 24.8%. One-hundred, twenty-five children were followed up at the outpatient ART Clinic, of which 42 (33.6%) were still in care at the end of the study. The median duration of co-trimoxazole preventive therapy was 1278 days. Conclusion: PCP was often the first presentation of HIV infection. Children with PCP still have poor outcomes. Despite the decline in PCP admissions, there was a high in-hospital mortality rate.Item The Impact of Enterprise and Supplier Development Programmes on the Growth of SMMEs in Gauteng, South Africa(University of the Witwatersrand, Johannesburg, 2022) Ramokgopa, Lebogang; Mlothswa, SamukeleWhile various studies have investigated the challenges that Small Medium and Micro Enterprises (SMMEs) face and many of them outline the support that is required by SMMEs, there have been limited studies that look into the effectiveness of government support interventions that are implemented through the public and private sectors. The effectiveness of Broad-Based Black Economic Empowerment Commission (B-BBEE) and Enterprise and Supply Development (ESD) support programmes and their impact on SMME growth have not been extensively interrogated through research. This knowledge is particularly important to investigate because SMMEs play a significant role in improving economic growth and reducing unemployment and equality levels. As such, this study sought to assess the impact of B-BBEE ESD programme support on the growth of SMMEs. The study employed qualitative methods and thematic analysis was used to analyse data. The sample size included 10 beneficiaries of B-BBEE ESD in Gauteng province, obtaining their views on participation experience. The findings suggest that ESD initiatives assist SMMEs in both financial and nonfinancial ways. However, participants usually believed that the benefits were limited and that partnerships may provide more value. Further, findings from the study highlighted the presence of constraints that impede ESD's capacity to provide an optimal service offering to SMMEs, resulting in restricted visibility for small enterprises. Some internal and external difficulties in delivering services to SMMEs were outlined based on the experience of beneficiaries. As such, it was recommended that enterprise and supplier development programs should avoid attempting to be all things to all people. The emphasis should be on an area in which they excel and on providing that service to SMMEs. This allows them to impart their specialized knowledge to small enterprises. To be effective, this focus should be sector or industry specificItem Blood management strategies in posterior corrective surgery for idiopathic scoliosis(University of the Witwatersrand, Johannesburg, 2022-11) Aftab, Mohammad Hamza Sultan; Ukunda, U.N.; Robertson, A.J.F.; Milner, B.Background: Corrective surgery for idiopathic scoliosis is associated with large volumes of blood loss and a need for blood transfusion. The aim of the study was to measure blood loss and blood products used intra-operatively in corrective surgery, and to identify modifiable factors that may influence blood loss. Methods: The study was a retrospective review of patients who underwent posterior corrective surgery for idiopathic scoliosis between 2015 and 2020. A total of 43 patients were identified, of which 36 met the inclusion criteria. Sociodemographic data, intra-operative blood loss parameters, transfusion requirements, and use of tranexamic acid, intra-operative cell salvage and ultrasonic bone scalpel were documented. Data were analysed to identify factors affecting intra-operative blood loss and blood transfusion. Results: The 36 patients (30 female, 6 male) had a median age of 16 (interquartile range: 13-17) years. The mean duration of surgery was 355 (+/-75.38) minutes and the average number of segments fused was 10.25 (+/- 1.87). The mean estimated blood loss was 722.22 (+/-328.30) mL with the mean percentage blood loss being 22.99 (+/-11.61) %. A total of 11 patients (30.56%) received a blood transfusion; in these patients every 139.58 mL of blood lost resulted in 1 unit of blood being transfused (p=0.005). Statistically significant differences in mean estimated blood loss were found with the use of tranexamic acid (p=0.018) and ultrasonic bone scalpel (p=0.01). The use of intra-operative cell salvage did not result in statistically significant differences in mean estimated blood loss. A direct correlation was also found with estimated blood loss and the duration of surgery (p=0.025), and the number of segments fused (p=0.005). Conclusion: Modifiable factors affecting intra-operative blood loss include the use of tranexamic acid, ultrasonic bone scalpel, duration of surgery and the number of segments fused. A multifactorial blood management strategy should be implemented to decrease blood loss and reduce the need for blood transfusion in corrective scoliosis surgery.