Browsing by Author "Kahn, Delawir"

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    A retrospective audit of the outcomes of the Fellow Of College Of Surgeons (FCS) (General Surgery) Final Examinations
    (2018) Kahn, Miriam; Kahn, Delawir; Navsaria, Pradeep H; Klopper, Juan
    Background and aim: An audit of the Fellowship of the College of Surgeons FCS (SA) Final Examination results has not been previously performed. The purpose of this study was to review and determine any predictors of outcome. Methods: The results of the FCS (SA) Final Examinations from October 2005, to and including, October 2014, were retrieved from the College of Medicine of South Africa database. The current format of the examinations consists of: two written essay question papers, an OSCE, two clinical cases and two vivas. These were retrospectively reviewed and analyzed. Predictors of failure or success were determined. Analysis was performed using IPython for scientific computing. Assumptions for the normal distribution of numerical values were made based on the Kolmogorov-Smirnov test and quantile-quantile plots. Normally distributed variables were analyzed by parametric tests. In all other cases nonparametric tests were employed. An alpha value of 0.05 was chosen to indicate statistical significance, using a confidence level of 95%. Results: During the 10-year study period, 472 candidates attempted the examinations. A total of 388 (82,2%) candidates were successful in the written component of the examination and were subsequently invited to participate in the oral/clinical component of the examinations. 9 Overall, 296 (62,7%) of candidates passed and 176 (37,3%) failed. A total of 19 candidates achieved less than 50% for both papers, yet still managed an average of more than 45%. A total of 15 (79%) of these candidates went on to fail the examination. There were 51 candidates who were invited to the oral examinations despite an average of less than 50% in the two papers, and 34 (67%) failed the overall examination. Similarly, 126 candidates were invited having failed one of the two papers of which 81 (64.3%) ultimately failed. A total of 49 candidates failed the OSCE, 82% of these candidates failed overall. There was strong correlation between paper one and paper two (r = 0.56, p-value < 0.01), oral one and oral two (r = 0.41, p-value < 0.01) and case one and case two (r = 0.38, p-value < 0.01). Similar correlations were seen between the averages of the papers versus the orals (r = 0.52, p-value < 0.01), the papers versus the cases (r = 0.5, p-value < 0.01) and the papers versus the OSCE (r = 0.54, p-vale < 0.01). Conclusion: The written papers are the main determinant of invitation to the second part of the examination. Candidates with marginal scores in the written component had an overall failure rate of 67%. Failing one paper and passing the other, resulted in an overall failure rate 64,3%. Failing the OSCE resulted in an overall 82% failure rate. With the high failure rate of candidates with marginal scores and with the inter-examination variability of the papers, it might be prudent to revisit both the process of invitation selection and the decision to continue with the long-form for the written component.
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    A Straight Left Heart Border: A New Radiological Sign of a Hemopericardium
    (2014) Nicol, Andrew John; Navsaria, Pradeep Harkison; Beningfield, Steve; Kahn, Delawir
    Background: Detection of a cardiac injury in a stable patient after a penetrating chest injury can be difficult. Ultrasound of the pericardial sac may be associated with a false negative result in the presence of a hemothorax. A filling in of the left heart border inferior to the pulmonary artery, called the straight left heart border (SLHB), is a radiological sign on chest X-ray that we have found to be associated with the finding of a hemopericardium at surgery. The aim of the present study was to determine if this was a reliable and reproducible sign. Methods: This was a prospective study of patients with a penetrating chest injury admitted between 1 October 2001 and 28 February 2009, who had no indication for immediate surgery, and were taken to the operating room for creation of a subxiphoid pericardial window (SPW). The chest X-ray was reviewed by a single trauma surgeon prior to surgery. Results: A total of 162 patients with a possible occult cardiac injury underwent creation of a SPW. Fifty-five of the 162 patients (34 %) were noted to have a SLHB on chest X-ray and a hemopericardium confirmed at SPW. The sensitivity of the SLHB sign was 40 %; specificity, 84 %; and positive predictive value, 89 %. (p = 0.005, Odds ratio 3.48, lower 1.41, upper 8.62). Conclusions: The straight left heart border is a newly described radiological sign that was highly significant in predicting the presence of a hemopericardium and should alert the clinician to a possible occult cardiac injury.
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    Acute Appendicitis in the Public and Private Sectors in Cape Town, South Africa
    (2014) Yang, Estin; Kahn, Delawir; Cook, Colin
    Compared to the Western world, the incidence of appendicitis is relatively low in South Africa, but with higher complication and rupture rates. Although there have been numerous studies published on appendicitis in South Africa, the literature is notably missing outcome data in the private sector. Therefore, this study aims to compare acute appendicitis in the public and private sectors in Cape Town, exploring patient characteristics, perforation rates, outcomes, and return to work.
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    An audit of the workload of an acute surgery unit in a tertiary academic hospital before and after the closure of a referring community hospital
    (2015) Moodie, Quintin Keith; Klopper, Juan; Kahn, Delawir
    Aim: An audit of the workload of an Acute Care Surgery Unit in a Tertiary Academic Hospital and an assessment of the impact on this Unit by the closure of a busy Community Hospital. Background: The primary mission of the Acute Care Surgery service is to provide timely surgical assessment, operative and/or non-operative management of the acutely ill non-trauma surgical patient. Both locally and internationally, fewer surgeons are perusing general practice, opting instead for subspecialty training, with no or only minimal time spent in emergency surgical care. This is demonstrated for example by evidence that some colorectal surgeons refer diseases of the appendix to the general surgeon, reflecting the narrow point of care that is being practiced in certain fields of surgery. In many cases acute care surgery has been described as a multidisciplinary approach involving Emergency and Trauma Surgery, and Critical Care Medicine.(1-3) In South Africa the rules and regulation by the Health Professions Council stipulates the requirement of training and qualifying as a General Surgeon, before pursuing Fellowship training in a field of subspeciality. As treatment paradigms shift and surgical emergency disease management evolves, we need properly trained surgeons that are willing to pursue the optimal emergency care (surgical or non-operative) for specific conditions in patients presenting with these acute surgical emergencies.(2,4) Groote Schuur Hospital (GSH) is privileged in its provision of an Acute Care Surgical Unit (ACSU) that functions in a tertiary environment and is affiliated with the University of Cape Town (UCT), the leading ranked University on the African Continent. The ACSU in GSH has 28 dedicated beds, and functions as a secondary and tertiary level General Surgery Unit excluding all acute trauma care. Provision is also made for the management of primary level surgical diseases. A neighboring surgical referral hospital, GF Jooste Hospital (GFJH), has 90 dedicated surgery beds. It is a Community Hospital, which caters for primary and secondary level diseases. Acute care is also given to tertiary level trauma and emergency surgical diseases. The unit at GFJH will be closing to allow for a reconstruction of the building, and thus the patient population will require access to alternate facilities whilst awaiting the reopening. A subset of these patient will have to be accommodated at GSH.
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    The current management of penetrating cardiac trauma
    (2012) Nicol, Andrew John; Kahn, Delawir
    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.
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    Evaluation of encapsulated liver cell spheroids in a fluidised-bed bioartificial liver for treatment of ischaemic acute liver failure in pigs in a translational setting
    (Public Library of Science, 2013) Selden, Clare; Spearman, Catherine Wendy; Kahn, Delawir; Miller, Malcolm; Figaji, Anthony; Erro, Eloy; Bundy, James; Massie, Isobel; Chalmers, Sherri-Ann; Arendse, Hiram
    Liver failure is an increasing problem. Donor-organ shortage results in patients dying before receiving a transplant. Since the liver can regenerate, alternative therapies providing temporary liver-support are sought. A bioartificial-liver would temporarily substitute function in liver failure buying time for liver regeneration/organ-procurement. Our aim: to develop a prototype bioartificial-liver-machine (BAL) comprising a human liver-derived cell-line, cultured to phenotypic competence and deliverable in a clinical setting to sites distant from its preparation. The objective of this study was to determine whether its use would improve functional parameters of liver failure in pigs with acute liver failure, to provide proof-of-principle. HepG2cells encapsulated in alginate-beads, proliferated in a fluidised-bed-bioreactor providing a biomass of 4-6×10 10 cells, were transported from preparation-laboratory to point-of-use operating theatre (6000miles) under perfluorodecalin at ambient temperature. Irreversible ischaemic liver failure was induced in anaesthetised pigs, after portal-systemic-shunt, by hepatic-artery-ligation. Biochemical parameters, intracranial pressure, and functional-clotting were measured in animals connected in an extracorporeal bioartificial-liver circuit. Efficacy was demonstrated comparing outcomes between animals connected to a circuit containing alginate-encapsulated cells (Cell-bead BAL), and those connected to circuit containing alginate capsules without cells (Empty-bead BAL). Cells of the biomass met regulatory standards for sterility and provenance. All animals developed progressive liver-failure after ischaemia induction. Efficacy of BAL was demonstrated since animals connected to a functional biomass (+ cells) had significantly smaller rises in intracranial pressure, lower ammonia levels, more bilirubin conjugation, improved acidosis and clotting restoration compared to animals connected to the circuit without cells. In the +cell group, human proteins accumulated in pigs' plasma. Delivery of biomass using a short-term cold-chain enabled transport and use without loss of function over 3days. Thus, a fluidised-bed bioreactor containing alginate-encapsulated HepG2cell-spheroids improved important parameters of acute liver failure in pigs. The system can readily be up-scaled and transported to point-of-use justifying development at clinical scale.
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    Flow velocity measurement in haemodialysis access using 4D MRI
    (2016) Downs, Jennifer; Kahn, Delawir; Franz, Thomas
    Treatment of renal failure while awaiting transplant requires vascular access, which comes with both complications and failure rates. In order to improve this, information about the AVF or AVG itself, as well as the haemodynamics is required. This data will then be used for computer modelling techniques and computational flow dynamics. Previously, the required imaging was provided by contrasted MRI, contraindicated in renal failure. Haemodynamic data was prvided by, amongst other things, duplex Doppler. New MRI software that provides imaging data as well as haemodynamic information without using contrast could be used to provide new high-quality data for modelling. Methods: This was a prospective pilot study. Six control cases (with no history of vascular illness or surgery of any kind to the right upper arm), as well as three grafts and five fistulae underwent phase contrast MR angiography of the right upper arm with a Siemens Magnetom Symphony 1.5T MRI Scanner. Images were then processed using Supertool in Matlab, and flow velocities at predetermined points on the brachial artery and cephalic vein, graft and fistula were calculated. Results: Velocities ranged from 5.8 cm/sec in a volunteer's brachial artery to 85.5 cm/sec in an arteriovenous fistula patient's brachial artery. Flow volumes in the cephalic vein or access varied from 6.9 ml/min. in a volunteer and up to 4398.1 ml/min. in an arteriovenous fistula. Graphical representations show marked haemodynamic changes throughout the imaged vessels. Conclusion: This technique provides good imaging and quantitative data about small vessel haemodynamics.
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    Global surgery - socioeconomic and geographic maldistribution of surgical resources
    (2016) Dell, Angela June; Kahn, Delawir
    Surgery is an indispensable part of any health system and improving access to safe surgery remains a challenge in the developing world. Surgery is emerging as a priority in global health, unfortunately information around the burden of surgical diseases or the available surgical resources is limited. South Africa is an Upper Middle Income Country (UMIC) and currently provides reasonable surgical services, however these services vary across regions, between urban and rural settings, as well as between public and private hospitals. There is no reliable data regarding the available surgical resources in South Africa, namely surgical beds, operating theatres and surgeons. These variables are essential in developing a National Surgical Plan to address the burden of surgical disease, however they are limited in the information they provide they provide regarding surgical capacity and need to be assessed in context with more robust indicators. This aim of this study was to quantify some of the specific surgical resources as identified by the World Health Organization (WHO) and the Lancet Commission. This research will contribute to the growing body of research regarding global surgery in South Africa and attempt to provide an analysis of metrics used to evaluate surgical systems. The research hypothesis was that the surgical resources in South Africa were limited, and that surgeons, theatres and hospital beds per capita are inadequate compared to developed countries and do not meet global recommendations. This involved a descriptive analysis of surgical resources and included the total number of hospitals, of hospital beds, the number of surgical beds, the number of general surgeons (specialist and non-specialist), and the number of functional operating theatres in South Africa. The surgical resources were analysed, both according to province and district, and a comparison was performed based on the population density. A comparison of the public and private facilities was undertaken with regard to the total numbers, as well as per population density. Lastly, a comparison was performed with other high and low income countries around the world. The results showed one hospital per 100 000 population, 186.64 hospital beds, 41.55 surgical beds, 1.78 specialist general surgeons, 2.90 non-specialist general surgeons, and 3.59 operating theatres per 100 000 people in South Africa. These numbers fell far below international recommendations, as well as developed countries such as the United Kingdom (UK) and United States of America (USA). Surgical resources were concentrated in metropolitan areas, and there were differences between the public and private sectors, with private hospitals having a greater number of surgical beds and operating theatres per population than public hospitals. These data indicated how surgical providers and basic infrastructure were distributed in South Africa, which will allow more accurate planning by government policymakers. Recommendations need to be tailored according to each sector as the needs of the patients and resources available are different. There is a need to acknowledge the major shortage of healthcare providers with implementation of the National Health Insurance (NHI). There is a need for validated instruments to accurately collect data and for reliable electronic information sharing which will improve data collection and analysis between rural and urban areas. Existing resources need to be utilized more effectively. These results showed that regional hospitals lack both specialist and non-specialist general surgeons. The international consensus was that performing surgery at district level hospitals improved access and lowered cost, however this will need recruitment of additional skilled personnel and infrastructure in order to support surgery at this level. This national audit has provided much needed data on the some of the available surgical resources may influence critical decision-making about funding distribution, resource and training post allocations, as well as address inequalities in service delivery.
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    Improvement of liver transplantation by reducing preservation-reperfusion injury
    (1999) van As, Arjan Bastiaan; Kahn, Delawir
    The liver differs from other solid organs in that it has a dual blood supply, receiving arterial blood via the hepatic artery and venous blood via the portal vein. The reperfusion injury which occurs after ischemia, has been studied to only a limited extent in the liver. In particular, the relative contribution of the portal venous blood and the hepatic arterial blood to the reperfusion injury has not been documented previously. During liver transplantation, implantation of the new liver is achieved by anastomosing the suprahepatic vena cava, the infrahepatic vena cava and the portal vein. At this stage, the liver is reperfused with portal venous blood only. Thereafter the hepatic arterial anastomosis is undertaken. The delay in providing the liver allograft with arterial blood will depend upon the difficulty in the dissection of the hepatic artery. The impact of the delay in rearterialization of the liver allograft has not been studied previously. Currently, the University of Wisconsin Solution is the gold standard for liver preservation. Celsior is a new cardioplegic solution, which has also been suggested for use for liver preservation. However, its role as a liver preservation solution has been studied to a limited extent. The aim of this study was: 1. To document the reperfusion injury after liver transplantation. 2. To document the relative contribution of the portal venous blood and the hepatic arterial blood to the reperfusion injury. 3. To investigate the impact of early rearterialization on the reperfusion injury after liver transplantation. 4. To investigate the effect of the new preservation solution, Celsior, on the reperfusion injury after liver transplantation. Large White X-Landrace pigs were subjected to orthotopic liver transplantation. The donor liver was stored in Eurocollins solution for 3 hours. The animals were randomly allocated to either rearterialization 60 minutes after portal reperfusion, rearterialization 20 minutes after portal reperfusion, simultaneously portal and arterial reperfusion, and rearterialization 20 minutes before portal venous reperfusion. In another experiment, the donor livers were stored in either Eurocollins solution, University of Wisconsin Solution, or Celsior. Blood samples were taken at various intervals and subjected to the following biochemical investigations. Malondialdehyde and vitamin A were used as markers of reperfusion injury. Hyaluronic acid levels were used as markers of endothelial cell function. Serum AST was used as a marker of hepatocellular injury. In summary, these studies showed that there was a significant reperfusion injury after portal venous reperfusion with no additional injury after rearterialization. Early rearterialization also resulted in a lesser reperfusion injury. There was also less hepatocellular injury with early rearterialization. Histological evidence of injury was also less in the livers which were rearterialized early. In addition, the livers preserved in Celsior had evidence of a lesser reperfusion injury. Thus in conclusion, in liver transplantation early rearterialization might result in better early graft function.
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    The inhibition of the Human Immunodeficiency Virus type 1 activity by crude and purified human pregnancy plug mucus and mucins in an inhibition assay
    (BioMed Central Ltd, 2008) Habte, Habtom; de Beer, Corena; Lotz, Zoe; Tyler, Marilyn; Schoeman, Leann; Kahn, Delawir; Mall, Anwar
    BACKGROUND:The female reproductive tract is amongst the main routes for Human Immunodeficiency Virus (HIV) transmission. Cervical mucus however is known to protect the female reproductive tract from bacterial invasion and fluid loss and regulates and facilitates sperm transport to the upper reproductive tract. The purpose of this study was to purify and characterize pregnancy plug mucins and determine their anti-HIV-1 activity in an HIV inhibition assay. METHODS: Pregnancy plug mucins were purified by caesium chloride density-gradient ultra-centrifugation and characterized by Western blotting analysis. The anti-HIV-1 activities of the crude pregnancy plug mucus and purified pregnancy plug mucins was determined by incubating them with HIV-1 prior to infection of the human T lymphoblastoid cell line (CEM SS cells). RESULTS: The pregnancy plug mucus had MUC1, MUC2, MUC5AC and MUC5B. The HIV inhibition assay revealed that while the purified pregnancy plug mucins inhibit HIV-1 activity by approximately 97.5%, the crude pregnancy plug mucus failed to inhibit HIV-1 activity. CONCLUSION: Although it is not clear why the crude sample did not inhibit HIV-1 activity, it may be that the amount of mucins in the crude pregnancy plug mucus (which contains water, mucins, lipids, nucleic acids, lactoferrin, lysozyme, immunoglobulins and ions), is insufficient to cause viral inhibition or aggregation.
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    Laparoscopy and loop colostomy : a new approach to extra-peritoneal rectal injuries
    (2003) Navsaria, Pradeep H; Kahn, Delawir
    Distal rectal washout and presacral drainage appear to have little or no influence on the morbidity and mortality in patients with low-energy trauma to the rectum. The ever-increasing popularity and obvious advantages of minimal access surgery have prompted surgeons to apply its use to a variety of surgical diseases, including trauma-related conditions. This study retrospectively reviews and examines the safety and efficacy of laparoscopy and the formation of a diverting sigmoid loop colostomy through an abdominal wall trephine, in a limited number of carefully selected patients with isolated extra-peritoneal rectal injuries. The patient is thus spared a major laparotomy wound. The value of distal rectal washout and presacral drainage in such injuries is also examined.
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    The pathological outcomes related to symptomatic impacted third molars and follicles as found in a private practice in South Africa
    (2013) Berezowski, Brian Mark; Kahn, Delawir; Phillips, Vincent Michael
    The aim of this study primarily was to review pathological reports of all symptomatic third molar teeth removed in a private practice, and to use the data to support or refute routine removal of third molar teeth. All patients who underwent third molar tooth removal for symptoms,either systemic or local ,in a private practice over a twenty year period between 1987 and 2007 were included in the study. Specimens were sent for histological assessment by Oral Pathologists. The patient records were reviewed retrospectively. A total of 3427 third molar teeth were included in the study. There were 68.75% specimens which had some sort of pathology. Only 0.3% of specimens were reported as normal dental follicular tissue. There were 31.25% specimens of hyperplastic follicular tissue which was considered non pathologic as they consisted of normal dental follicular tissue with a mild chronic inflammatory cell infiltrate. However the 68.75% pathologic lesions consisted of 14.44% specimens with early dentigerous cysts, 8.11% with dentigerous cysts, 42.80% of paradental cysts and the remainder with other pathologies. The majority of the patients were in the second and third decades and mostly female. The age distribution of the patients suggested a progression from hyperplastic follicular tissue with a peak occurring at 17 years, to early dentigerous cysts at 19 years, to dentigerous cysts at 21 years. Paradental cyst formation, with a peak incidence at 19 years of age formed a large number of the pathological lesions found, and accounted for a large number of patients seeking treatment, owing to the symptoms associated. This study represents an analysis of the largest number of symptomatic third molar teeth submitted for histological assessment known. The data obtained was used to review the guidelines for the management of third molar teeth. From this study it can be concluded that symptomatic impacted third molar teeth should be removed early in the third decade in order to avoid general or local symptoms suffered by these patients.
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    A review of living donor liver transplantation: why is regeneration more rapid in the recipient compared to the donor?
    (2009) Ibirogba, Sheriff B; Kahn, Delawir
    Living donor liver transplantation (LDLT) is now well established and performed on a routine basis in many major centres around the world. LDLT is feasible because of the capacity of both the remnant donor liver and the transplanted partial liver to undergo liver regeneration. However it has been demonstrated that liver regeneration in the recipient is rapid, whereas restoration of liver mass in the donor is delayed. This discrepancy in the rate of regeneration could be due to the presence of hepatotrophic factors and the use of immunosuppression in the recipient. The aims of the studies were to determine if hepatotrophic factors and immunosuppression (Cyclosporine) could modify the restoration of the liver mass after partial hepatectomy in rats.
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    The role of crude human saliva and purified salivary MUC5B and MUC7 mucins in the inhibition of Human Immunodeficiency Virus type 1 in an inhibition assay
    (BioMed Central Ltd, 2006) Habte, Habtom H; Mall, Anwar S; de Beer, Corena; Lotz E, Zoe; Kahn, Delawir
    BACKGROUND: Despite the continuous shedding of HIV infected blood into the oral cavity and the detectable presence of the AIDS virus at a high frequency, human saliva is reported to inhibit oral transmission of HIV through kissing, dental treatment, biting, and aerosolization. The purpose of this study was to purify salivary MUC5B and MUC7 mucins from crude saliva and determine their anti-HIV-1 activities. METHODS: Following Sepharose CL-4B column chromatography and caesium chloride isopycnic density-gradient ultra-centrifugation, the purity and identity of the mucins was determined by SDS-PAGE and Western blotting analysis respectively. Subsequently an HIV-1 inhibition assay was carried out to determine the anti-HIV-1 activity of the crude saliva and purified salivary mucins by incubating them with subtype D HIV-1 prior to infection of the CD4+ CEM SS cells. RESULTS: Western blotting analysis confirmed that the mucin in the void volume is MUC5B and the mucin in the included volume is MUC7. The HIV inhibition assay revealed that both the crude saliva and salivary MUC5B and MUC7 mucins inhibited HIV-1 activity by 100%. CONCLUSION: Although the mechanism of action is not clear the carbohydrate moieties of the salivary mucins may trap or aggregate the virus and prevent host cell entry.
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    A study comparing outcomes of appendectomy between HIV-infected and HIV-negative patients
    (2017) Sobnach, Sanju; Kahn, Delawir
    Background: The high prevalence of Human Immunodeficiency Virus (HIV) has added a new dimension to the management and outcomes of many general surgical conditions in South Africa. However, there is a paucity of data describing the impact of HIV status on surgical outcomes in our setting. Appendicitis is the most common gastrointestinal emergency, and its surgical outcomes in areas of high HIV prevalence are poorly described in the literature. Thus, the aim of this study is to describe and compare the outcomes of appendectomy between HIV-infected (HIV+) and HIV-negative (HIV-) patients. Methods: This is a retrospective study of patients undergoing appendectomy at a large regional hospital over a 12-month period. Demographic data, duration of pre-hospital symptoms, HIV status, surgical approach, operative findings, histopathology reports, hospital stay and complications were recorded. Data for the HIV+ and HIV-patient cohorts were then described, analysed and compared. Statistical analysis was performed using the Chi-Squared or Fisher's exact test for non-continuous variables, and non- parametric ANOVA and Wilcoxon ranked sum test for continuous variables. A P-value less than 0·05 was considered statistically significant. Results: The study group comprised 134 patients; 18 (13.4 %) tested positive for HIV. HIV+ patients were significantly older (mean age of 29.3 vs. 20.3 years, P= 0.002) and had longer duration of pre-hospital symptoms (mean of 3.94 vs. 2.57 days, P= 0.03). Postoperative complications (44.4 % vs. 17.2 %, P= 0.03) and lengthier hospital stays (7.28 days vs. 5.95 days, P= 0.004) were also more frequently seen in the HIV+ patients. There were no differences in appendiceal rupture rates, histopathological findings and mortality. Conclusion: HIV infection is common in patients admitted with clinical features of acute appendicitis in South Africa. Presentation in HIV+ patients was delayed, and surgery was associated with significant postoperative morbidity and longer hospital stay.
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    The flaws of laser Doppler in negative-pressure wound therapy research
    (2014) Kairinos, Nicolas; McKune, Andrew; Solomons, Michael; Hudson, Donald A; Kahn, Delawir
    Recent studies, using modalities other than laser Doppler, have indicated that perfusion during negative-pressure wound therapy (NPWT) is reduced, contrary to world literature. The aim of the present study was to evaluate whether the measuring technique of the laser Doppler could be influenced by the compressive nature of NPWT dressings and whether this could explain the conflicting findings. A hypothesis that it may be possible for laser Doppler to record similar readings to those obtained during NPWT by merely compressing tissues manually was tested on 12 NPWT dressings, with each undergoing an alternating series of manual compressive forces and NPWT (−125 mmHg). During the periods of NPWT (n = 12), the mean perfusion recording increased in five experiments, reduced in six, and remained unchanged in one. During the period when manual pressure was applied (n = 12), there was a mean increase in perfusion in six experiments and a reduction in six. The type of change in perfusion (increase or decrease) was the same for both NPWT and manual pressure in 10 of the 12 experiments. In conclusion, laser Doppler can incorrectly record increased perfusion when tissues are compressed, implying that it is flawed in the field of NPWT research as tissues are always compressed to some degree by the NPWT dressing.
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    The interaction between exercise induced muscle damage and fatigue on neural regulation and exercise performance during submaximal and maximal running
    (2018) Noel, Colin Byron; Kahn, Delawir; Lambert, Mike
    Aim: To study the effects of muscle damage and fatigue on neuromuscular preactivation and performance during submaximal and maximal running. Setting: University of Cape Town, Sports Science Institute of South Africa. Methods: 12 male distance runners (19 - 39 years of age) with a minimum weekly training distance of 40 kilometers per week were randomly assigned to either control (n = 6) or experimental (n = 6) groups. Subjects’ visited the laboratory over an 11 day period during which testing included a submaximal and maximal run (5 km time trial) on the first and last day of testing. Neuromuscular preactivation, rating of perceived exertion, heart rate and performance times were recorded during the performance trials. The intervention between performance trials included two 40 minute bouts on a treadmill at 70 % peak treadmill running speed at –10 º elevation (experimental) or horizontal (control). Results: Running performance in the 5 km time trial (5K) improved in the experimental group alone by an average of 40 seconds over 5 km (P < 0.04) in the presence of muscle damage and without altered neuromuscular preactivation. There was no evidence any interaction between altered neuromuscular activity with regard to fatigue and muscle damage during submaximal and maximal running. Evidence of muscle damage in the experimental group was supported by a significant group versus time interaction effect in subjective pain score for daily living and increased plasma creatinine kinase levels in the experimental group (P<0.03). A significant decrease in rating of perceived exertion (RPE) was observed in both groups during both the submaximal (P<0.04) and 5 km time trial (P<0.03) post intervention. There was an interaction effect for group versus pre-post 5K (P<0.06), with the post 5K RPE in the experimental group showing an average decreased RPE score of 2.6 for each kilometer and the control group an average decrease in RPE score of only 0.03. Conclusion: The research design of this study was appropriate to study the interaction between fatigue and muscle damage during submaximal and maximal running. This study suggests that there is no neuromuscular compensation after muscle damage and that EMG is regulated similarly for both fatigue and muscle damage during submaximal and maximal running. Improvement in running performance and decreased rating of perceived exertion after muscle damage is due to some unknown variable.
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    Violence against women : a prospective study of women presenting to a South African trauma centre
    (2015) Dedekind, Britta; Nicol, Andrew; Kahn, Delawir
    Background - Violence against Women is a major public health issue, and it is universally under reported. Objective - To conduct an injury surveillance of severe or life threatening violent acts against women, to determine the demographics of the injured women and to identify the nature of the perpetrators. Methods - A standardized structured questionnaire administered in an interview conducted on female patients admitted to the Trauma Centre at Groote Schuur Hospital as a result of interpersonal violence. Age, level of education, employment status, housing and substance abuse was recorded.