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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Review of Damage Control Laparotomy (DCL) outcomes in a Major Urban Trauma Center

Kruger, Andries Michiel 15 September 2020 (has links)
Introduction Damage control laparotomy (DCL) in an urban trauma centre is associated with high mortality. Aim The purpose of this prospective study was to review the outcomes of DCL in a level one urban trauma centre, looking particularly at primary closure rate and other factors influencing outcomes. Methods All patients undergoing DCL for penetrating trauma from May 2015 to July 2017 were retrieved from the prospectively recorded eTHR data base. Data retrieved were basic demographics, mechanism of injury, perioperative vitals and biochemical parameters. Injury severity was described by the Revised Trauma Score (RTS), Penetrating Abdominal Trauma Index (PATI), Injury Severity Score (ISS) and Trauma and Injury Severity Score (TRISS). Indications for DCL were determined as well as length of ICU stay, days of ventilation, number of procedures and primary abdominal closure rates. Complications and mortality were recorded. Results During the study period, 51 patients underwent DCL. Three patients sustained stab wounds and 47 patients suffered from gunshots. Only 1 female was included in the study with the other 50 being male. The mean age was 28 years and 4 months (range 15 to 48 years). Indications for laparotomy were haemodynamic instability (n = 27) and peritonism in stable patients (n = 22). The means for the different severity scores were RTS 7.36, ISS 17.5, TRISS 93.76 and PATI 28. Means were calculated for different physiological markers of trauma (lowest pH 7.12, highest lactate 7.11, lowest core temp 34.9˚C and lowest systolic BP 63.8 mmHg). The organs most commonly injured, in decreasing frequency, were small bowel (n = 33), large bowel (n = 25), abdominal vasculature (n = 22), liver (n = 18), stomach (n = 14), kidney (n = 10), diaphragm (n = 10), spleen (n = 9) and pancreas (n = 8). DCL procedures performed were abdominal packing (n = 36), bowel ligation (n = 30), vascular shunting (n = 5) and shunting of the ureter (n = 1). The median number of laparotomies done per patient was 3, with a primary fascial closure rate of 69%. The mortality rate was 29%. Conclusion DCL in our setting is associated with a 29% mortality rate. Severe acidosis, massive blood transfusion in first 24hours and median PATI score more than 47 are independent factors associated with increased mortality.
62

Randomised study of EndoRings™-assisted vs. standard colonoscopy for detection of polyps in at risk individuals with Lynch Syndrome

Dhar, Rohin 11 September 2020 (has links)
Introduction: Lynch syndrome (LS) is an autosomal dominant condition and is the most common cause of inherited colorectal cancer (CRC), contributing to approximately 3%-5% of newly diagnosed cases of colorectal malignancy. LS affected individuals bear 18% – 53% lifetime risk for development of CRC. The only therapeutic approach to prevent development of CRC among individuals with LS is periodic colonoscopic screening for detection and removal of adenomas and polyps, which are the precursors for cancer. Despite being the current gold standard, and accounting for all other variables (such as experience of the physician), conventional colonoscopy has been known to sometimes miss detecting adenomas/polyps, specifically those present in the folds of the colonic mucosa and on the inner luminal wall of the colonic flexures. EndoRings™ assisted colonoscopy has therefore been developed to improve colonoscopy outcomes in terms of enhancing adenoma detection rates (ADR)/polyp detection rates (PDR) and involves flexible silicone rings mechanically stretching the colonic folds and thus enhancing total colon visualisation. Objectives: The present study aims to primarily investigate the efficacy of EndoRings™ assisted colonoscopy compared to traditional colonoscopy in terms of ADR/PDR in a known cohort of individuals with LS in a South African setting. Methods: The study was conducted as a cross-sectional randomised controlled trial. Individuals from the Northern Cape province of South Africa with LS were enrolled into the study during our Annual Northern Cape Colonoscopy Outreach trip for the year 2015. A total of 54 individuals (per-protocol) were included in the study and randomised blindly using computer randomisation into a control arm undergoing standard colonoscopy (n=27) and a study arm undergoing EndoRings™-assisted colonoscopy (n=27). Number of polyps detected (the primary outcome) along with a set of secondary outcomes was recorded in real time on data sheets for each individual and statically analysed using IPython. Results: The female to male ratio in the EndoRings™ group was 19:8 versus 15:12 in the standard colonoscopy group (P = 0.40) whereas the mean age of patients was 43.98±15.27 years and 44.26±14.67 years (P = 0.05) respectively. The average number of polyps detected in the EndoRings™ group was 1.4 versus 0.9 in the non-EndoRings™ group (P = 0.60). Conclusion: The present study outcomes observed comparable ADR/PDR in EndoRings™ assisted versus standard colonoscopy with no statistically significant difference. This result may be due to the study's limitations (small sample size) and design. Though no statistically significant conclusions could be reached, EndoRings™ assisted colonoscopy was perceived as being helpful in terms of increasing total colonic visualisation and allowing better scope stabilisation during interventions. Comparable intubation times, withdrawal times, total procedure times and similar complication rates were observed in both study arms. Although this study demonstrated non-inferiority of EndoRings™ compared to standard colonoscopy, further studies with a larger sample size in an easily accessible population over a longer study period are recommended.
63

Five-year review of breast-conserving therapy (BCT) for breast carcinoma: Surgical margins, re-excision and local recurrence in a single tertiary center

Nashidengo, Pueya Mekondjo January 2017 (has links)
Background: Breast cancer burden is on the increase in the developing world. Breast-conserving therapy (BCT) is prescribed for early breast cancer. It is the wide local excision of the tumour usually followed by radiation treatment to the breast. It is the mainstay treatment for carefully selected patients with early breast cancer presenting to the Groote Schuur Hospital's Oncology and Endocrine Surgical unit, Cape Town South Africa. There has not been a formal audit to review the outcomes of BCT in the unit. Objectives: The objective of this study is to determine and analyse the excision margins for all the wide local excisions and the re-excision and local recurrence rates during the study period. Methods: This is a histopathological and oncology records review of the patients that have undergone BCT in the unit from the 1st of January 2006 until the 31st of December 2010. The University of Cape Town's Faculty of Health Sciences Human Research Ethics Committee granted approval. Data points accrued included patient age, pathological tumour size and nodal status, histological tumour type, oestrogen receptor status, presence of lymphovascular invasion, volume of specimen excised, margin status, management of involved or close margins, completeness of radiotherapy, ipsilateral breast recurrence rate and total duration of follow up. Results: A total of 192 patients had BCT during the study period. The mean age is 53 years (range 25 to 84 years). A median of 229.5 cm3 volume of specimen was excised (range 4 cm3 to 10530 cm3). Infiltrating ductal carcinoma was the commonest histological type at 79.1%. 42.7% were pT1 tumours, 49.0% pT2 tumours and 2.6 % pT3. The resection margin status are: positive margins rate of 15.1%, 8.3 % close margin (≤ 1 mm), 35.9% 1 – 5 mm, 23.4% 6 – 10 mm and > 10 mm 17.2%. An overall of 26 (13.5%) patients underwent a repeat surgical procedure. 16 (8.3%) had re-excision and 10 (5.2%) had a mastectomy. Residual tumour was present in 50% of the re-excisions and 63.6% of mastectomies. As per category of the resection margins, 68.9% of patients with positive margins had repeat surgery (48.3% re-excision and 20.6% mastectomy). 31.1% of patients with positive margins did not have repeat surgery despite the indication due to advanced age, loss to follow up or residual tumour on the deep chest wall margin. 80.8% patients completed radiotherapy treatment post breast-conserving surgery. At a median follow up of 60 months (range 1 to 108 months), a total of 11 (6.8%) patients had ipsilateral breast local recurrence. Median time to recurrence is 39 months (range 12 to 106 months). Conclusion: Positive and close margin re-excision and local recurrence rates in our unit are acceptable and comparable to other units in South Africa and internationally.
64

The incidence and impact of Human Papillomavirus in HIV infected transplant patients

Botha, Janie January 2018 (has links)
Background: Human Papillomavirus (HPV) is a common sexually transmitted infection, associated with condylomata acuminata, anogenital squamous intraepithelial lesions, and ultimately invasive squamous cell carcinoma. HPV types 16 and 18 are the most common subtypes in individuals with cervical cancer. The association with these two subtypes in individuals with squamous carcinoma of the anus is fundamentally the same as with cervical cancer, and also affects the same high risk phenotype. Human imunnodeficiency virus (HIV) positive transplant patients have two modes of immunosuppression - the disease itself and the additional immunosuppression required after transplantation, which intuitively places them at a higher risk for this type of infection, if compared to their HIV negative counterparts. Aim: The first aim is to determine the prevalence of HPV-associated cytological and pathological abnormalities of the anus in HIV positive kidney transplant recipients and the second aim is to determine if HIV positive solid organ recipients carry higher risk for having HPV of the anus than HIV negative solid organ recipients. Materials and methods: This is a cross sectional study, conducted at the Transplant unit of Groote Schuur Hospital. 14 HIV positive renal transplant recipients and 14 age matched HIV negative renal transplant recipients with similar immunosuppression regimens and time from transplantation were selected. Ethical approval for the study was obtained from the UCT Ethics committee (HREC/REF: 595/2014). Informed consent was obtained from all participants. Samples for cytology and histology were taken from the anal canal. Demographic data was collected, date of HIV diagnosis, duration on anti-retroviral drugs, time since transplant, type of immunosuppression, whether there was visible condylomata or not and if there were any lesions suspicious of cancer. Cytology and histology was correlated with clinical findings. The statistics were analysed with Stata® software. Results: Mean age was 40.8y ±7.5 (range 27-52) in the HIV positive study group and 41y ±14.4 (range20-62) in the HIV negative control group. HIV positive patients were screened 40.1 months ± 21 (range 13-74.6m) post renal transplant. HIV negative patients were screened 55.9 months ± 23.3 (range 8.9-80 m) post renal transplant. Two HIV positive patients had anal warts, compared to 1 in the HIV negative group. No statistically significant difference could be demonstrated between the occurrence of intra-epithelial neoplasm on cytology in the HIV positive and negative groups. However, HIV positive patients had a higher incidence of HPV on histology that was statistically significant. There was no evidence of squamous intra-epithelial neoplasm found on histology in either group. Conclusions: Evidence of HPV of the anus was demonstrated in both groups, there was no demonstrable statistical significance in occurrence between the two groups' cytology. Histology, however, yielded a significant number of patients with HPV in the HIV positive group. None of the patients had evidence of invasive malignancy.
65

Damage control laparatomy for abdominal gunshot wounds: indications, mortality and long term outcomes

Twier, Khaled January 2017 (has links)
Background: Outcomes of patients subjected to damage control laparotomy (DCL) for abdominal gunshot wounds (GSWs) remains relatively unknown. There is limited evidence as to which variables may reliably predict morbidity and mortality. The aim of this study was to evaluate the impact of DCL on long term morbidity and survival, to determine clinical characteristics associated with increased mortality, and to evaluate the indications for DCL in patients with abdominal GSWs. Methods: A retrospective study of patients who underwent a damage control laparotomy for abdominal GSWs at Groote Schuur Hospital (GSH) was conducted. Data was collected on 50 consecutive trauma patients over a 4.5 years period (between August 1st, 2004 and September 30th, 2009). Patients were stratified by, age, preoperative and intraoperative physiological parameters, trauma indices, numbers and locations of abdominal GSWs, extra abdominal involvement, intensive care unit and hospital length of stay, morbidity and mortality. Unadjusted and adjusted estimates of the association between these factors and the odds of survival were computed with univariate and multivariate logistic regression. Results: Most of the patients were male (96%) with a mean age 29.7 year. Most patients had a single abdominal gunshot wound (60%). Liver injuries were the most common injury (58%) followed by small bowel (44%), 20 majors venous (40%), and colonic injury (38%) injuries. The overall mortality was 54%. The mean of length stay in the intensive care unit was 7 days with overall mean hospital length of stay of 13 days. Factor an associated with a decreased odd of survival included Penetrating abdominal trauma index(PATI) >25, pre-operative infusion of less than two litres of crystalloids, intra-operative blood lactate level >8mmol/L, massive transfusion >10 units PRBCs. Conclusion: The overall mortality of patients requiring DCL for abdominal GSWs was 54%. In this limited study, there is significant evidence that after controlling for confounding PATI score of >25 is associated with a decreased odds of survival (OR:0.20, p-value 0.04).
66

The current management of penetrating cardiac trauma

Nicol, Andrew John January 2012 (has links)
Includes bibliographical references. / The vast majority of patients with penetrating cardiac injuries do not reach the hospital alive as the pre-hospital mortality rate for these injuries is in the region of 86%. The patients that do reach the hospital alive are potential survivors and it is obviously crucial that any cardiac injury is detected and managed appropriately. Most of these injuries present with either cardiac tamponade or hypovolaemic shock and are relatively straightforward to diagnose and require immediate surgery. There is, however, a group of patients that are relatively stable with an underlying cardiac injury and it is in these patients that a potential or occult cardiac injury needs to be identified.
67

Development of a multi-stage purification process for serum-derived exosomes and evaluation of their regenerative capacity

de Boer, Candice 11 September 2020 (has links)
Exosomes are secreted membrane vesicles (30-100 nm) found in tissue culture media and various body fluids that have potential as therapeutics and disease biomarkers. Current literature has reported regenerative benefits for blood-derived exosomes but the majority of these studies purified exosomes using ultracentrifugation (UC), a method that has been found to have high levels of protein contamination. Here the regenerative capacity of exosomes isolated by size exclusion chromatography (SEC), a method shown to reduce protein contamination, from human serum was assessed. SEC isolates were found to contain suitably sized vesicles and exosomal markers (CD9, CD81 and TSG101). These isolates allowed for cellular uptake of a range of fluorescent labels and enhanced cellular fibroblast proliferation and endothelial sprout formation in a 3D spheroid-based angiogenesis assay. Further to this, functionality was shown to be retained after incubation of the isolates for 21 days at 37°C. Though a promising indication of regenerative potential, it was found that the isolates contained significant levels of ApoB containing lipoproteins (up to 15 µg ApoB/ml). It was shown that these lipoproteins were predominately the very low and intermediate density lipoproteins. It was found that low-density lipoprotein can impact exosome uptake studies that use fluorescent nucleic acid, protein and lipid dyes. As a substantial extraneous lipoprotein content could also interfere with other downstream applications and analyses such as proteomic analysis, a multistep purification method was developed. A simple 3-step density gradient (DG) UC was introduced prior to SEC that incorporated a high-density iodixanol cushion overlaid by a 18% iodixanol step containing UC concentrated human serum that was then overlaid with 6% iodixanol. This DG relied on flotation to remove lipoproteins. After the multi-step purification (UC DG SEC) ApoB and ApoA1 were not detectable by enzyme-linked immunosorbent assay and western blotting respectively. The UC DG SEC isolates were positive for CD9 and TSG101 and morphologically, as viewed by transmission electron microscopy, had the canonical exosome shape and size. Nanoparticle tracking analysis showed that though exosome marker levels were similar, there were 100 times more particles in SEC purified isolates relative to those from UC DG SEC, emphasising the extent of lipoprotein removal. Proteomic analysis identified 224 proteins in UC DG SEC isolates relative to the 135 from SEC, with substantial increases in exosome-associated proteins and reductions in lipoproteins. The UC DG SEC exosomes still elicited a significant increase in cell proliferation of human dermal fibroblasts but no increase in endothelial sprout formation. After subcutaneous implantation in a rat model, the highly purified exosomes potentially increased an angiogenic response. In conclusion, we show that serum SEC-derived exosomes with much reduced protein content do have regenerative properties but contain contaminating lipoproteins. Our new isolation technique isolated purer serum exosomes that retained cell proliferation stimulation and potentially enhanced an in vivo angiogenic response. This approach should render the isolated exosomes more suitable for biomarker discovery, molecular composition determination and biological function analysis.
68

Upper limb ischaemia : a twelve year experience

Du Toit, Johannes Marthinus January 2014 (has links)
Includes bibliographical references. / Introduction: Upper limb ischaemia (ULI) is a relatively uncommon, but well recognized vascular entity. The sequalae of impaired function or amputation of an arm can be devastating to the individual with loss of independence and / or livelihood. There remains much to be learned that can only be established through good quality studies. This project was aimed at developing a comprehensive, but broad overview of ULI, specific to the population we serve. Aims: The objective was to review the Vascular Surgery Unit’s experience with ULI, with particular emphasis on defining the pattern and distribution of disease and pathological profile, describing key demographic and clinical features and reporting on conventional clinical outcomes. Areas of interest, with the potential for further research, were identified. Methods: Retrospective descriptive study. All patients that underwent a surgical intervention for ULI between January 2000 and December 2011, were included in the audit. Approval from the Department of Surgery Research Committee and Human Research Ethics Committee was obtained prior to accessing data (Appendix 1 & 2).A research folder was compiled for each patient. On completion of the data collection process, the findings were analyzed and compared to current literature on this topic. Results: Sixty-four patients with ULI were managed surgically during the 12 year study period. A male: female ratio of 0.60 (as opposed to 0.96 from 2011 Census figures), was reported. The thrombo-embolic subgroup of patients (n=30), were notably younger than expected (mean age of 55 years) compared to the UEAOD subgroup (n=12, mean age of 57 years). Approximately 48% were of mixed ethnicity, correlating well with 2011 Census figures. Referrals were predominately received from Secondary Hospitals (84%) situated within the Cape Metropole. 55% Presented with acute ULI, of which 40% were classified as Rutherford grade IIa and 17% diagnosed with established compartment syndrome. The majority of chronic ULI patients, presented with signs of tissue necrosis (48%).Other indications for intervention included upper extremity claudication symptoms (31%), rest pain (14%) as well as neuro-vascular symptoms (7%). A disproportionately high prevalence of cigarette smoking (83%,with an average of 31 pack years)was identified in the UEAOD subgroup. 27% Of patients were not receiving adequate pharmacological therapies aimed at addressing pre-existing risk factors, as proposed by the TASC II document. Thrombo-embolism was the single largest aetiological factor identified (47%),with the majority of occlusions (57%) occurring at the level of the brachial artery. A left-sided predominance with a ratio of 2:1, was noted. Approximately 47% of patients with UEAOD, were younger than 55 years. A clear proximal pattern of disease was observed (66% of lesions within the subclavian artery). Eighty-nine procedures were performed in 64 patients (78 open, 5 exclusively endovascular with a combined open / endovascular approach implemented in 6 patients). The 30-day mortality rate was 7.8%. Systemic complications were observed in 13% with 23% sustaining some form of procedural complication. Twenty amputations were performed in 64 patients, of which 6 were major amputations. The 30-day amputation rate after an attempt at revascularization, was 12.5%. Adherence to follow-up was poor (51% at 6 months), limiting interpretation of follow-up data. Conclusion: Although few firm conclusions could be drawn, this review has expanded our overall perspective of ULI, specific to the population we serve. It is anticipated that the publication of our institutional data will create a clinical awareness and facilitate future research projects in this field. A collaborative research effort between South African vascular units will facilitate comparison of different institutional experiences and enable pooled data analysis, perhaps further defining the pattern of upper limb vascular disease by identifying distinct geographical confounders.
69

Management of left-sided malignant colonic obstruction : an audit of a stent based protocol

Warden, C January 2011 (has links)
Includes abstract. / Includes bibliographical references. / Colonic self-expanding metallic stents (SEMS) are proven to be safe and effective in the management of selected cases of malignant colonic obstruction. Since 2005, we have used endoscopic decompression with SEMS as the primary treatment of all patients with left-sided obstructing colorectal cancer, in the absence of perforation. The purpose of the study was to assess the safety and efficacy of this management protocol.
70

Should abdomino-perineal resection be considered when a defunctioning stoma is required for anal canal squamous cell carcinoma?

Kloppers, Jacobus Christoffel January 2014 (has links)
Includes bibliographical references. / Combined modality treatment (CMT) is the preferred treatment for anal squamous cell carcinoma, but a small subgroup needs a defunctioning colostomy with temporary intent. The aim of this study was to evaluate the stoma closure rate of patients needing defunctioning colostomies prior to CMT for anal squamous cell carcinoma (SCC) at Groote Schuur Hospital (GSH). The key objective was to assess if abdomino-perineal resection (APR) should be offered as primary treatment modality for the subgroup of patients needing a defunctioning stoma and CMT.

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