MSc (Med), Surgery, Faculty of Health Sciences, University of the Witwatersrand

A growing body of evidence suggests that the potential exists to reduce morbidity and high mortality rates associated with major surgery in high-risk patients. Dopexamine is a dopamine analogue with agonist activity at β2-adrenoceptors and dopaminergic receptors that has been used to maintain tissue perfusion in critically ill and high-risk surgical patients with the aim of improving clinical outcomes. Postoperative complications occur more frequently in the presence of poor tissue microvascular flow and oxygenation, and dopexamine has been shown to improve these abnormalities. However, the effect of dopexamine on clinical outcomes is less clear, and the findings of randomized trials have proved inconsistent. These conflicting findings might be explained by dose-related differences in the hemodynamic and immunologic effects of dopexamine. The series of investigations that make up this thesis set out to explore the nature of any such dose-related effects and reveal potent anti-inflammatory effects of dopexamine in the absence of haemodynamic effects.

A Research Report submitted to the Faculty of Medicine of the University of the Witwatersrand Johannesburg in partial fulfilment of the requirements for the degree of Master of Medicine in the discipline of surgery 1991 / Severe intra-abdominal infection (IAI) carries a high mortality. Methods of treatment such as radical peritonaal debridement, continuos post-operative lavage and local intra-peritonaal instillation of anti-biotics have not improved. [Abbreviated Abstract. Open document to view full version] / MT2016

Objective: The primary objective was to describe the level of surgical trainee autonomy during non-trauma emergency laparotomy (NTEL) operations in Rwanda and South Africa. The secondary objective was to identify potential associations between trainee autonomy, and patient mortality and reoperation. Design, Setting, and Participants: This was a prospective, observational study of NTEL operations at three teaching hospitals in South Africa and Rwanda over a oneyear period from September 1, 2017 – August 31, 2018. A total of 543 operations on adults over the age of 18 years who underwent NTEL performed by the acute care and general surgery services were included. Results: surgical trainees led three quarters of NTEL operations, and of these, 72% were performed autonomously in Rwanda and South Africa. Trainees were less likely to perform the operations autonomously for patients who were: age ≥ 60 years, had ASA classification ≥ III, had cancer or TB. Notably, trainee autonomy was not significantly associated with reoperation or mortality. Conclusions: trainees were able to gain autonomous surgical experience without impacting mortality or reoperation outcomes, while still providing surgical support in a high-demand setting. More in-depth studies to understand the association of high trainee autonomy with surgical competency and patient safety is needed.

Purpose: Sonography provides a fast, portable, and noninvasive method for patient assessment. However, the benefit of providing real-time ultrasound (US) imaging and fluid quantification shortly after patient arrival has not been explored. The objective of this study was to prospectively validate a US hemoperitoneum scoring system developed at our institution and determine whether sonography can predict a therapeutic operation. Methods: For 12 months, prospective data on all patients undergoing a trauma sonogram were recorded. All sonograms positive for free fluid were given a hemoperitoneum score. The US score was compared with initial systolic blood pressure and base deficit to assess the ability of sonography to predict a therapeutic laparotomy. Results: Forty of 46 patients (87%) with a US score ≥ 3 required a therapeutic laparotomy. Forty-six of 54 patients with a US score < 3 (85%) did not need operative intervention. The sensitivity of sonography was 83% compared with 28% and 49% for systolic blood pressure and base deficit, respectively, in determining the need for therapeutic operation. Conclusion: We conclude that the majority of patients with a score ≥ 3 will need surgery. The US hemoperitoneum scoring system was a better predictor of a therapeutic laparotomy than initial blood pressure and/or base deficit.

A anestesia do paciente equino acometido por síndrome do abdômen agudo ainda é uma das situações mais desafiadoras enfrentada pelo médico veterinário anestesiologista na pratica clínica. Apesar dos inúmeros avanços alcançados na área de ventilação mecânica, monitoramento avançado do status volêmico e atendimento do paciente critico, o equilíbrio entre a melhor estratégia de ventilação, de modo a minimizar a ocorrência de shunt e espaço morto, e a otimização dos parâmetros de oxigenação e hemodinâmica para que a perfusão sanguínea para os tecidos periféricos seja mantida, ainda não foi determinada para cavalo afetado por síndrome cólica. O objetivo deste trabalho foi avaliar o impacto de dois valores diferentes de pressão positiva ao final da expiração (PEEP) sobre os parâmetros de ventilação, oxigenação, hemodinâmica e consumo de fármacos vasopressores em equinos submetidos a laparotomia exploratória em decorrência de quadros de abdômen agudo de diferentes etiologias. Para isso foram utilizados 20 animais, sendo 12 machos e 8 fêmeas, pesando 431&#177;95 kg e encaminhados para o serviço de cirurgia de grandes animais da Faculdade de Medicina Veterinária e Zootecnia de Universidade de São Paulo (FMVZ/USP). Após avaliação pré-anestésica os animais foram pré-medicados com xilazina (0,6mg/kg-1) pela via intravenosa, decorridos 10 minutos realizou-se a indução da anestesia com cetamina (2,2mg/kg-1) associada a diazepam (0,05mg/kg-1). Os animais foram então posicionados em decúbito dorsal, mantidos em ventilação mecânica por volume controlado, com volume corrente de 14mL/kg e submetidos a manobra de recrutamento alveolar por escalonamento da PEEP, de maneira crescente a cada 5 minutos até 22 cmH2O, seguida do escalonamento decrescente, de forma que os animais foram então divididos sistematicamente em 2 grupos: PEEP constante de 12 cmH2O (Grupo PEEP12, n=10) ou PEEP constante de 17 cmH2O (Grupo PEEP17, n=10) durante todo o procedimento anestésico. O grupo PEEP12 apresentou valores de pressão arterial média (PAM) e pH significativamente maiores durante todo o período após a instituição do tratamento, bem como menor consumo de dobutamina e noradrenalina para a manutenção da PAM&gt;60 mmHg. No grupo PEEP12 houve ainda uma tendência de valores maiores de base excesso após a instituição do tratamento. Não houve diferença entre os dois grupos para os valores dos parâmetros de oxigenação no período pós anestésico. / The equine patient suffering from acute abdomen syndrome anesthesia remains one of the biggest challenges for the veterinary anesthesiologist. Despite many advances on mechanical ventilation, volemic status monitoring and critical care patient management it is still extremely difficult to achieve the balance between the best ventilation strategy to minimize the occurrence of ventilation mismatch and the optimization of cardiovascular parameters to keep blood perfusion to peripheral tissues within normal ranges. Therefore, the aim of this study was to assess the effects of a stepwise increase in airway pressure recruitment and two different values of positive end expiratory pressure (PEEP) on ventilatory, oxygenation and hemodynamics parameters as well as vasoactive drugs consumption on horses undergoing exploratory laparotomy. Thus, twenty client-owned horses, weighing 431&#177; 95 kg, refered to the Large Animal Surgery Service of the Faculty of Veterinary Medicine and Animal Science, at the University of São Paulo were included on the study. The animals were premedicated with xilazine (0,6mg/kg-1) and after 10 minutes the anesthesia was induced with ketamine (2,2 mg/kg-1) and diazepam (0,05 mg/kg-1). The subjects were positioned in dorsal recumbence, maintained in volume controlled mechanical ventilation, with tidal volume of 14ml/kg. After 30 min of instrumentation the recruitment maneuver (RM) was performed by PEEP titration with increments of 5 cmH2O every 5 min up to a PEEP of 20 cmH2O followed by decremental PEEP titration until 12 cmH20 (Group PEEP12, n=10) or 17 cmH2O (Group PEEP 17, n=10) until the end of surgical procedure. The Group PEEP12 had significantly higher values of mean arterial blood pressure (MAP) and pH for 100 minutes after the RM was performed. The animals in this group also needed less vasoactive drugs (dobutamine and noradrenaline) to keep the MAP&gt;60mmHg during the whole anesthesia time. There was no difference between group PEEP12 a group PEEP 17 regarding oxygenation parameters 30 minutes after the anesthesia was ended.

A anestesia do paciente equino acometido por síndrome do abdômen agudo ainda é uma das situações mais desafiadoras enfrentada pelo médico veterinário anestesiologista na pratica clínica. Apesar dos inúmeros avanços alcançados na área de ventilação mecânica, monitoramento avançado do status volêmico e atendimento do paciente critico, o equilíbrio entre a melhor estratégia de ventilação, de modo a minimizar a ocorrência de shunt e espaço morto, e a otimização dos parâmetros de oxigenação e hemodinâmica para que a perfusão sanguínea para os tecidos periféricos seja mantida, ainda não foi determinada para cavalo afetado por síndrome cólica. O objetivo deste trabalho foi avaliar o impacto de dois valores diferentes de pressão positiva ao final da expiração (PEEP) sobre os parâmetros de ventilação, oxigenação, hemodinâmica e consumo de fármacos vasopressores em equinos submetidos a laparotomia exploratória em decorrência de quadros de abdômen agudo de diferentes etiologias. Para isso foram utilizados 20 animais, sendo 12 machos e 8 fêmeas, pesando 431&#177;95 kg e encaminhados para o serviço de cirurgia de grandes animais da Faculdade de Medicina Veterinária e Zootecnia de Universidade de São Paulo (FMVZ/USP). Após avaliação pré-anestésica os animais foram pré-medicados com xilazina (0,6mg/kg-1) pela via intravenosa, decorridos 10 minutos realizou-se a indução da anestesia com cetamina (2,2mg/kg-1) associada a diazepam (0,05mg/kg-1). Os animais foram então posicionados em decúbito dorsal, mantidos em ventilação mecânica por volume controlado, com volume corrente de 14mL/kg e submetidos a manobra de recrutamento alveolar por escalonamento da PEEP, de maneira crescente a cada 5 minutos até 22 cmH2O, seguida do escalonamento decrescente, de forma que os animais foram então divididos sistematicamente em 2 grupos: PEEP constante de 12 cmH2O (Grupo PEEP12, n=10) ou PEEP constante de 17 cmH2O (Grupo PEEP17, n=10) durante todo o procedimento anestésico. O grupo PEEP12 apresentou valores de pressão arterial média (PAM) e pH significativamente maiores durante todo o período após a instituição do tratamento, bem como menor consumo de dobutamina e noradrenalina para a manutenção da PAM&gt;60 mmHg. No grupo PEEP12 houve ainda uma tendência de valores maiores de base excesso após a instituição do tratamento. Não houve diferença entre os dois grupos para os valores dos parâmetros de oxigenação no período pós anestésico. / The equine patient suffering from acute abdomen syndrome anesthesia remains one of the biggest challenges for the veterinary anesthesiologist. Despite many advances on mechanical ventilation, volemic status monitoring and critical care patient management it is still extremely difficult to achieve the balance between the best ventilation strategy to minimize the occurrence of ventilation mismatch and the optimization of cardiovascular parameters to keep blood perfusion to peripheral tissues within normal ranges. Therefore, the aim of this study was to assess the effects of a stepwise increase in airway pressure recruitment and two different values of positive end expiratory pressure (PEEP) on ventilatory, oxygenation and hemodynamics parameters as well as vasoactive drugs consumption on horses undergoing exploratory laparotomy. Thus, twenty client-owned horses, weighing 431&#177; 95 kg, refered to the Large Animal Surgery Service of the Faculty of Veterinary Medicine and Animal Science, at the University of São Paulo were included on the study. The animals were premedicated with xilazine (0,6mg/kg-1) and after 10 minutes the anesthesia was induced with ketamine (2,2 mg/kg-1) and diazepam (0,05 mg/kg-1). The subjects were positioned in dorsal recumbence, maintained in volume controlled mechanical ventilation, with tidal volume of 14ml/kg. After 30 min of instrumentation the recruitment maneuver (RM) was performed by PEEP titration with increments of 5 cmH2O every 5 min up to a PEEP of 20 cmH2O followed by decremental PEEP titration until 12 cmH20 (Group PEEP12, n=10) or 17 cmH2O (Group PEEP 17, n=10) until the end of surgical procedure. The Group PEEP12 had significantly higher values of mean arterial blood pressure (MAP) and pH for 100 minutes after the RM was performed. The animals in this group also needed less vasoactive drugs (dobutamine and noradrenaline) to keep the MAP&gt;60mmHg during the whole anesthesia time. There was no difference between group PEEP12 a group PEEP 17 regarding oxygenation parameters 30 minutes after the anesthesia was ended.

Yes / IMPORTANCE Patients undergoing emergency laparotomy have high mortality, but few studies exist to improve outcomes for these patients. OBJECTIVE To assess whether a collaborative approach to implement a 6-point care bundle is associated with reduction in mortality and length of stay and improvement in the delivery of standards of care across a group of hospitals. DESIGN, SETTING, AND PARTICIPANTS The Emergency Laparotomy Collaborative (ELC) was a UK-based prospective quality improvement study of the implementation of a care bundle provided to patients requiring emergency laparotomy between October 1, 2015, and September 30, 2017. Participants were 28 National Health Service hospitals and emergency surgical patients who were treated at these hospitals and whose data were entered into the National Emergency Laparotomy Audit (NELA) database. Post-ELC implementation outcomes were compared with baseline data from July 1, 2014, to September 30, 2015. Data entry and collection were performed through the NELA. INTERVENTIONS A 6-point, evidence-based care bundle was used. The bundle included prompt measurement of blood lactate levels, early review and treatment for sepsis, transfer to the operating room within defined time goals after the decision to operate, use of goal-directed fluid therapy, postoperative admission to an intensive care unit, and multidisciplinary involvement of senior clinicians in the decision and delivery of perioperative care. Change management and leadership coaching were provided to ELC leadership teams. MAIN OUTCOME AND MEASURES Primary outcomes were in-hospital mortality, both crude and Portsmouth Physiological and Operative Severity Score for the enumeration of Mortality and morbidity (P-POSSUM) risk-adjusted, and length of stay. Secondary outcomes were the changes after implementation of the separate metrics in the care bundle. RESULTS A total of 28 hospitals participated in the ELC and completed the project. The baseline group included 5562 patients (2937 female [52.8%] and a mean [range] age of 65.3 [18.0-114.0] years), whereas the post-ELC group had 9247 patients (4911 female [53.1%] and a mean [range] age of 65.0 [18.0-99.0] years). Unadjusted mortality rate decreased from 9.8% at baseline to 8.3% in year 2 of the project, and so did risk-adjusted mortality from a baseline of 5.3% to 4.5% post-ELC. Mean length of stay decreased from 20.1 days during year 1 to 18.9 days during year 2. Significant changes in 5 of the 6 metrics in the care bundle were achieved. CONCLUSIONS AND RELEVANCE A collaborative approach using a quality improvement methodology and a care bundle appeared to be effective in reducing mortality and length of stay in emergency laparotomy, suggesting that hospitals should adopt such an approach to see better patient outcomes and care delivery performance. / This study was funded by The Health Foundation, United Kingdom, as part of a Scaling Up Award.

Der Median- und der Oberbauchquerschnitt werden als operative Zugänge bei Pankreas- und Magenoperationen verwendet. Bislang ist jedoch ungeklärt, welche Schnittführung hinsichtlich der Lungenfunktion, des Wundschmerzempfindens und der Morbidität vorteilhafter ist. Zwischen 4/96 und 4/98 wurden alle Patienten, die wegen einer Pankreas- oder Magenerkrankung elektiv primär operiert wurden, in eine prospektiv-randomisierte Studie aufgenommen. Ziel der Studie war es, unter Einschluß der Parameter Wundheilung, Lungenfunktion (FVC und FEV 1) und Wundschmerzempfinden als Hauptzielkriterien den günstigsten Zugangsweg für eine Pankreas- bzw. Magenoperation zu bestimmen. Als Nebenzielkriterien wurden die Operationsdauer, der Temperaturverlauf, die Inzidenz pulmonaler Komplikationen, die Bewertung des kosmetischen Ergebnisses sowie die Dauer des Klinikaufenthaltes und die Kliniksletalität untersucht. Insgesamt wurden 94 Patienten in die Studie aufgenommen, von denen 52 am Pankreas (quer : median = 27:25) und 42 am Magen (quer : median=20:22) operiert wurden. Für die FVC und das FEV 1 konnten postoperativ bei allen Patienten signifikant erhöhte Werte nach einem Oberbauchquerschnitt gegenüber einem Medianschnitt gezeigt werden. Es bestand allerdings keine Korrelation zur Inzidenz postoperativer pulmonaler Komplikationen oder Wundkomplikationen. Die Patienten mit einem Oberbauchquerschnitt gaben im postoperativen Verlauf ein signifikant geringeres Wundschmerzempfinden an. Die Eröffnungszeit des Oberbauches war bei einer medianen Laparotomie signifikant vermindert. Für die Verschlußzeit und die gesamte Operationsdauer bestanden wie auch für die Inzidenz allgemeiner Komplikationen sowie die Kliniksletalität und die Dauer des Kliniksaufenthaltes keine signifikanten Unterschiede zwischen den beiden operativen Zugängen. Die Bewertung des kosmetischen Ergebnisses zeigte bei einer signifikant kürzeren Wundlänge nach einer medianen Laparotomie ebenfalls keinen signifikanten Unterschied. Nach einem Oberbauchquerschnitt kommt es postoperativ zu einer besseren Lungenfunktion und zu einem niedrigeren Wundschmerzempfinden ohne Einfluß auf die Komplikationsrate. / The median and the transverse laparotomy are both common incisions in operations of the pancreas and the stomach. The aim of this study was to determine which of the two incisions is best with respect to the pulmonary function, the incisional pain and the morbidity. In a series between 4/96 and 4/98 all patients undergoing major laparotomy for a disease of the pancreas or the stomach were enrolled in this study. The healing of the wound, the pulmonary function (FVC and FEV1), and the incisional pain were taken into account. Further parameters were the duration of the operation, the body temperature, the incidence of postoperative pulmonary complications, the cosmetic result of the wound healing, the duration of the hospitalisation, and the lethality. In total, 94 patients met the study criteria. 52 were operated for a disease of the pancreas (transverse:midline = 27:25) and 42 for a disease of the stomach (transverse:midline = 20:22). After a transverse incision compared to a midline incision the patients had a significantly higher FVC and FEV1. But there was no correlation to the incidence of postoperative pulmonary complications or complications of the wound healing. The patients with a transverse incision suffered significantly lower incisional pain. In contrast, midline incisions took less time to perform. No differences were noticed with regard to the incidence of further postoperative complications, the letality and the duration of hospital stay. Neither were there any evident differences between the cosmetic results of the two ways of aproach. The respiratory function is better, and the sensation of pain lower after a transverse incision but there is no influence on the number of postoperative complications.

Orientador: José Jurandir Fagliari / Banca: Rafael Resende Faleiros / Banca: Delphim da Graça Macoris / Banca: José Dantas Ribeiro / Banca: Daniela Gomes da Silva / Resumo: Este estudo teve como objetivo geral comparar os efeitos da laparotomia exploratória e do uso da fenilbutazona em bovinos e bubalinos. Para isso foram avaliados o perfil bioquímico, o proteinograma e o hemograma de 28 animais dos quais 14 eram búfalas e 14 vacas, todas fêmeas não lactantes, distribuídas em quatro grupos - VT: vacas tratadas com fenilbutazona; VC: vacas controle; BT: búfalas tratadas com fenilbutazona e BC: búfalas controle. Os animais dos grupos VT e BT receberam dose única de 10 mg/kg de fenilbutazona, por via intravenosa, uma hora antes da cirurgia. Foram coletadas amostras de sangue antes da laparotomia (0h) e 1(1h), 6(6h), 12(12h), 24(24h), 48(48h), 72(72h), 96(96h) e 120 horas (120h) e 15(15d) e 30(30d) dias após a intervenção. Os valores de creatinina foram mais elevados nas búfalas, e não sofram alteração devido à cirurgia, ou ao tratamento. O tratamento com fenilbutazona aumentou a concentração sérica de HDL em vacas e búfalas. Dentre as proteínas de fase aguda, a concentração de ceruloplasmina se elevou em todos os grupos de 48 horas a 120 horas após a cirurgia. A concentração sérica de haptoglobina se elevou mais nos grupos das búfalas do que nas vacas. A hemopexina foi verificada apenas na espécie bubalina e apenas até o 5º dia. O tratamento com fenilbutazona não alterou a contagem de hemácias nem o volume globular. Todas as vacas e búfalas apresentaram neutrofilia 12 horas após a laparotomia. O teor de fósforo aumentou no grupo controle das búfalas (BC) e no grupo tratado (BT), às 72h e 96h, respectivamente. O magnésio se apresentou, no início do experimento (0h) e ao final (30d), significativamente maior nos grupos das búfalas (BT e BC). A laparotomia e ou o tratamento com fenilbutazona não interferiram nas concentrações de sódio, potássio e cálcio ionizado / Abstract: This study aims to compare the effect of exploratory laparotomy and treated with phenylbutazone in bovine and buffaloes. To pursue this purpose, biochemical profile, proteinogram and blood count cell tests were performed in 28 animals, of which 14 were buffaloes and 14 cows, all of then non-nursing, distributed in four groups - VT: cows treated with phenylbutazone; VC: control cows; BT: buffaloes treated with phenylbutazone and BC: control buffaloes. Animals from VT and BT received a single administration of 10 mg/kg of phenylbutazone, intravenously one hour before surgery. Blood samples were taken before laparotomy (0h) and 1(1h), 6(6h), 12(12h), 24(24h), 48(48h), 72(72h), 96(96h) e 120 horas (120h) e 15(15d) e 30(30d) days after surgery. Creatinine values were higher in buffaloes, and there were no changes, despite surgery or treatment. HDL showed different values in both species, due to surgical procedure. The use of phenylbutazone increased serum HDL in cows and buffaloes. Among acute phase proteins, serum haptoglobin showed higher values in buffaloes than in cows. Hemopexina was foundetected only in buffaloes and until the 5th day. Treatment with phenylbutazone did not change RBCs or globular volume values. Cows and buffaloes showed neutrophilia 12 hours after laparotomy. Phosphorus content increased in control buffaloes (BC) and in the treated buffaloes (BT) at 72h and 96h, respectively. Magnesium presented higher itself at the beginning of the experiment (0h) and end (30d) in buffaloes groups (BT and BC). Laparotomy or treatment with phenylbutazone did not changed sodium, potassium and calcium ionized values / Doutor