Browsing by Subject "Time Factors"

Now showing 1 - 8 of 8
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    Avoiding allogenic blood transfusions in endoscopic angiofibroma surgery
    (2016) Wasl, Hisham; McGuire, Jessica; Lubbe, Darlene
    BackgroundSurgical approaches for many tumours are often limited by blood loss, exposure and risk to vital anatomical structures. Therefore, the standard of care for certain skull base tumours has become endoscopic transnasal resection. Other surgical disciplines often use cell salvage techniques, but review of the otolaryngology literature revealed very few case reports. This study investigated the value and safety of salvage-type autologous blood transfusion during the endoscopic resection of juvenile nasopharyngeal angiofibromas (JNA).MethodsJNA is a rare vascular nasal tumour and the study extended over a 3-year period to obtain adequate patient numbers. All patients undergoing endoscopic resection during this period were included in the population sample. Ten patients with JNA were identified and underwent embolization prior to the endoscopic resection. In all cases the intraoperative blood salvage apparatus was used. Close post-operative monitoring was performed.ResultsHomologous blood transfusion could be avoided in all cases. Postoperative monitoring revealed transient bacteraemia in two cases where the leukocyte filter was not used, but no evidence of septicaemia.ConclusionsPerioperative cell saver and autologous blood transfusion in endonasal JNA surgery is safe. Homologous blood transfusion can be avoided by using this technique. The use of cell salvage allows for single stage surgery without the need to abandon surgery due to excessive blood loss and its future use is promising.
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    Open Access
    Changes in self-reported HIV testing during South Africa's 2010/2011 national testing campaign: gains and shortfalls
    (2016) Maughan-Brown, Brendan; Lloyd, Neil; Bor, Jacob; Venkataramani, Atheendar S
    HIV counselling and testing is critical to HIV prevention and treatment efforts. Mass campaigns may be an effective strategy to increase HIV testing in countries with generalized HIV epidemics. We assessed the self-reported uptake of HIV testing among individuals who had never previously tested for HIV, particularly those in high-risk populations, during the period of a national, multisector testing campaign in South Africa (April 2010 and June 2011).
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    Long-Term Left Ventricular Remodelling in Rat Model of Nonreperfused Myocardial Infarction: Sequential MR Imaging Using a 3T Clinical Scanner
    (2012) Saleh, Muhammad G; Sharp, Sarah-Kate; Alhamud, Alkathafi; Spottiswoode, Bruce S; van der Kouwe, André J W; Davies, Neil H; Franz, Thomas; Meintjes, Ernesta M
    Purpose. To evaluate whether 3T clinical MRI with a small-animal coil and gradient-echo (GE) sequence could be used to characterize long-term left ventricular remodelling (LVR) following nonreperfused myocardial infarction (MI) using semi-automatic segmentation software (SASS) in a rat model. Materials and Methods. 5 healthy rats were used to validate left ventricular mass (LVM) measured by MRI with postmortem values. 5 sham and 7 infarcted rats were scanned at 2 and 4 weeks after surgery to allow for functional and structural analysis of the heart. Measurements included ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV), and LVM. Changes in different regions of the heart were quantified using wall thickness analyses. Results. LVM validation in healthy rats demonstrated high correlation between MR and postmortem values. Functional assessment at 4 weeks after MI revealed considerable reduction in EF, increases in ESV, EDV, and LVM, and contractile dysfunction in infarcted and noninfarcted regions. Conclusion. Clinical 3T MRI with a small animal coil and GE sequence generated images in a rat heart with adequate signal-to-noise ratio (SNR) for successful semiautomatic segmentation to accurately and rapidly evaluate long-term LVR after MI.
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    Meeting national response time targets for priority 1 incidents in an urban emergency medical services system in South Africa: More ambulances won’t help
    (2015) Stein, Christopher; Wallis, Lee; Adetunji, Olufemi
    BACKGROUND: Response time is viewed as a key performance indicator in most emergency medical services (EMS) systems. OBJECTIVE: To determine the effect of increased emergency vehicle numbers on response time performance for priority 1 incidents in an urban EMS system in Cape Town, South Africa, using discrete-event computer simulation. METHOD: A simulation model was created, based on input data from part of the EMS operations. Two different versions of the model were used, one with primary response vehicles and ambulances and one with only ambulances. In both cases the models were run in seven different scenarios. The first scenario used the actual number of emergency vehicles in the real system, and in each subsequent scenario vehicle numbers were increased by adding the baseline number to the cumulative total. RESULTS: The model using only ambulances had shorter response times and a greater number of responses meeting national response time targets than models using primary response vehicles and ambulances. In both cases an improvement in response times and the number of responses meeting national response time targets was observed with the first incremental addition of vehicles. After this the improvements rapidly diminished and eventually became negligible with each successive increase in vehicle numbers. The national response time target for urban areas was never met, even with a seven-fold increase in vehicle numbers. CONCLUSION: The addition of emergency vehicles to an urban EMS system improves response times in priority 1 incidents, but alone is not capable of the magnitude of response time improvement needed to meet the national response time targets.
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    Risk factors for unstructured treatment interruptions and association with survival in low to middle income countries
    (2016) McMahon, James H; Spelman, Tim; Ford, Nathan; Greig, Jane; Mesic, Anita; Ssonko, Charles; Casas, Esther C; O’Brien, Daniel P
    Abstract Background Antiretroviral therapy (ART) treatment interruptions lead to poor clinical outcomes with unplanned or unstructured TIs (uTIs) likely to be underreported. This study describes; uTIs, their risk factors and association with survival. Methods Analysis of ART programmatic data from 11 countries across Asia and Africa between 2003 and 2013 where an uTI was defined as a ≥90-day patient initiated break from ART calculated from the last day the previous ART prescription would have run out until the date of the next ART prescription. Factors predicting uTI were assessed with a conditional risk-set multiple failure time-to-event model to account for repeated events per subject. Association between uTI and mortality was assessed using Cox proportional hazards, with a competing risks extension to test for the influence of lost to follow-up (LTFU). Results 40,632 patients were included from 11 countries across 33 sites (17 Africa, 16 Asia). Median duration of follow-up was 1.61 years (IQR 0.54–3.31 years), 3386 (8.3 %) patients died, and 3453 (8.5 %) were LTFU. There were 14,817 uTIs, with 10,162 (25 %) patients having more than one uTI. In the adjusted model males were at lower risk of uTI (aHR 0.94, p < 0.01, and age 20–59 was protective compared to <20 years (20–39 years aHR 0.87, p < 0.01; 40–59 years aHR 0.86, p < 0.01). Preserved immune function, as measured by higher CD4 cell count, was associated with a reduced rate of uTI compared to CD4 <200 cells/μL (CD4 200–350 cells/μL aHR 0.89, p < 0.01; CD4 >350 cells/μL aHR 0.87, p < 0.01), whereas advanced clinical disease was associated with increased uTI rate (WHO stage 3 aHR 1.10, p < 0.01; WHO stage 4 aHR 1.21, p < 0.01). There was no relationship between uTI and mortality after adjusting for disease status and considering LTFU as a competing risk. Conclusions uTIs were frequent in people in ART programs in low-middle income countries and associated with younger age, female gender and advanced HIV. uTI did not predict survival when loss to follow-up was considered a competing risk. Further evaluation of uTI predictors and interventions to reduce their occurrence is warranted.
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    Temporary vascular shunting in vascular trauma: A 10-year review from a civilian trauma centre
    (2013) Oliver, J C; Gill, H; Nicol, A J; Edu, S; Navsaria, P H
    BACKGROUND: Temporary intravascular shunts (TIVSs) can replace immediate definitive repair as a damage control procedure in vascular trauma. We evaluated their use in an urban trauma centre with a high incidence of penetrating trauma. METHOD: A retrospective chart review of all patients treated with a TIVS in a single centre between January 2000 and December 2009. RESULTS: Thirty-five TIVSs were placed during the study period: 22 were part of a damage control procedure, 7 were inserted at a peripheral hospital without vascular surgical expertise prior to transfer, and 6 were used during fixation of a lower limb fracture with an associated vascular injury. There were 7 amputations and 5 deaths, 4 of the TIVSs thrombosed, and a further 3 dislodged or migrated. Twenty-five patients underwent definitive repair with an interposition graft, 1 primary anastomosis was achieved, and 1 extra-anatomical bypass was performed. Five patients with non-viable limbs had the vessel ligated. CONCLUSIONS: A TIVS in the damage control setting is both life- and limb-saving. These shunts can be inserted safely in a facility without access to a surgeon with vascular surgery experience if there is uncontrollable bleeding or the delay to definitive vascular surgery is likely to be more than 6 hours. A definitive procedure should be performed within 24 hours.
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    The burden of imported malaria in Cape Town, South Africa
    (2014) Opie, Jessica; Freeks, Roschelle; Du Pisani, Louis Almero
    BACKGROUND: The Western Cape Province of South Africa (SA) is not malaria endemic; however, a considerable number of patients present with malaria to our healthcare services. OBJECTIVES: To establish the frequency of patients presenting with malaria at Groote Schuur Hospital (GSH), Cape Town, SA, and to describe their demographics, clinical outcomes and laboratory findings. METHODS: An observational, retrospective, descriptive study was conducted, which included all patients presenting with smear-positive malaria to GSH over a 4-year period between 1 April 2008 and 31 March 2012. RESULTS: During the study period, 134 malaria patients presented to GSH for management; 85% (n=114) were male, median age was 27 years. Of the total smear-positive tests, 96% (n=128) were Plasmodium falciparum, 3% (n=4) P. ovale, and in 1% (n=2) the species was not identified. The number of malaria patients increased markedly, from 6 cases in 2008 to 50 cases in 2012. Of the patients, 48.3% (n=57) were from Somalia, 8.5% (n=10) from SA and 29% (n=30) from other African countries. One SA patient acquired transfusion-transmitted malaria from a pooled platelet product, and the other SA patients had travelled to malaria-endemic areas. The remaining cases were from countries outside of Africa, including 13% (n=15) from Bangladesh. Almost two-thirds (62%; n=72) were admitted to hospital with a median length of stay of 3 days (range 1 - 32). Clinical outcomes were good with only one death and the remaining patients being discharged. CONCLUSION: Imported malaria is imposing a significant burden on health resources. The costs of medical care for the emergency treatment of foreign nationals needs to be recognised, and adequately budgeted for.
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    Validation of a guideline-based composite outcome assessment tool for asthma control
    (2007) Spencer, Sally; Mayer, Bhabita; Bendall, Kate L; Bateman, Eric D
    BackgroundA global definition of asthma control does not currently exist. The purpose of this study was to validate two new guideline-based composite measures of asthma control, defined as totally controlled (TC) asthma and well controlled (WC) asthma.MethodsWe used data from 3416 patients randomised and treated in the multi-centre Gaining Optimal Asthma controL (GOAL) study. The criteria comprising the asthma control measures were based on Global Initiative for Asthma/National Institutes of Health guidelines. This validation study examined the measurement properties of the asthma control measures using data from run-in, baseline, 12 and 52 weeks. Forced expiratory volume in 1 second (FEV1) and the Asthma Quality of Life Questionnaire (AQLQ) were used as the reference criteria in the validation analysis.ResultsBoth measures had good discriminative ability showing significant differences in FEV1 and AQLQ scores between control classification both cross-sectionally and longitudinally (p < 0.001). Overall both of the composite measures accounted for more of the variance in FEV1 after 52 weeks than the individual components of each asthma control measure. Both of the reference criteria were independently related to each asthma control measure (p < 0.0001). The measures also had good predictive validity showing significant differences in FEV1 and AQLQ scores at 52 weeks by control classification at 12 weeks (p < 0.0001).ConclusionThe guideline-based composite asthma control measures of WC asthma and TC asthma have good psychometric properties and are both valid functional indices of disease control in asthma.