INTRODUCTION: The Modified Blalock Taussig (BT) shunt is the most common palliative procedure in neonatal cardiac repair to secure pulmonary blood flow (3-6) despite high mortality and morbidity rates of 4-14% (3,5) and 9-18% (4,5) respectively. The high risk of thrombosis and stenosis associated with the polytetrafluoroethylene (PTFE) material that is currently used for BT shunts significantly contributes to these high mortality and morbidity rates. Thrombosis and stenosis occur in 3-12% of patients (1,5), primarily due to the lack of endothelium of the synthetic PTFE graft. This study hypothesizes that a preserved autologous umbilical vein could be a feasible replacement for the PTFE graft. Experiments were performed to examine and optimize preservation methods of umbilical veins for use as BT shunts. METHODS: Umbilical cords (n=45) were collected from healthy neonates and umbilical vein segments were preserved in either static (n=145) or flow conditions (n=84) for 7 days or 14 days in varying media. Samples of each vein were collected at time of harvest (Day 0) and at the end of culture and compared by burst pressure, histopathology, platelet adhesion and scanning electron microscopy (SEM). RESULTS: Burst pressure strength of veins from Day 0 to up to two weeks of preservation did not significantly differ (431 ± 229 mmHg vs 438 ± 244 mmHg). Overall histology demonstrated an improved morphology in endothelial and medial layers of the segments preserved in flow culture with UW + 5% HPL for 7 days. Platelet adhesion testing demonstrated significantly less platelet attachment in flow samples compared to static, indicating less endothelial injury. SEM showed greater cellular flow-alignment and consistency of the endothelium in flow samples. CONCLUSION: Flow culture utilizing UW plus 5% HPL adequately preserves morphology and function of the endothelium. Preserved autologous umbilical veins stand as a viable option to replace the current PTFE graft used for BT shunts due to the presence of an endothelium.

Clostridium difficile ist einer der führenden Nosokomialkeime in Bezug auf postoperative Diarrhoe. Die Inzidenz ist steigend und der Verlauf bei fulminanter Infektion häufig fatal. Es besteht der Anspruch der Vermeidung schwerer Verläufe und der horizontalen Verbreitung des Erregers. Ziel der Arbeit war, für den prä-, intra- und postoperativen Zeitraum Risikofaktoren zu identifizieren, welche Einfluss auf Ausprägung und Schwere der Infektion hatten. Die vorliegende klinische Studie umfasst 2.823 Patienten mit Diarrhoe nach kardiochirurgischem Eingriff, darunter 1.256 Patienten mit Clostridium-difficile-Nachweis, welche im Herzzentrum Leipzig von April 1999 bis April 2011 operativ versorgt worden sind. Die Datenanalyse erfolgte retrospektiv an zuvor festgelegten Parametern, die mittels statistischer Verfahren analysiert wurden. Besonderes Augenmerk wurde auf die Entwicklung gastrointestinaler Komplikationen und die Mortalität gelegt. Risikofaktoren für eine fulminante CDI waren u.a. männliches Geschlecht, kardiopulmonale Komorbiditäten, Diabetes mellitus Typ II, Verwendung von Assist-Systemen, perioperative Transfusionstherapie, sowie lange Operationszeiten und ein verlängerter Aufenthalt auf Intensivstation. Das Überleben bei fulminanter Infektion war mit einer Sterblichkeit von 63,4% bei einer 30-Tages-Mortalität von 21,6% deutlich schlechter als das der Vergleichsgruppen. Die Identifikation der perioperativen Risikofaktoren soll eine individualisierte Stratifizierung und damit die optimale Überwachung von Hochrisikopatienten für einen frühen Therapiebeginn und im besten Falle eine Prävention möglich machen.

There is significant variation between individual patients in the magnitude and pattern of their systemic response to cardiac surgery. Poor outcomes in these patients have been associated with a dysfunctional host response. This thesis seeks to define such variability at the level of gene expression by sequential analysis of transcription before and after surgery for a low risk group of patients undergoing elective cardiac surgery and cardiopulmonary bypass (CPB) patients using expression microarray profiling. To that aim, we analysed sequential global gene expression patterns in circulating peripheral blood leukocytes. We also investigated the role of DNA sequence variation in modulating the observed changes in gene expression. This approach allowed us to identify important genetic modulators and novel biological pathways and gain new insights into the mechanisms that regulate the host response to surgery.

Background: Decreased right ventricular function after coronary artery bypass graft surgery is a well-known phenomenon. The use of an artificial circuit and of cardioplegia during cardiopulmonary bypass (conventional coronary artery bypass graft surgery) has been evoked as possible reason for this dysfunction. With the availability of cardiac stabilisers (Octopus or Starfish®), bypass surgery on a beating heart is now possible without the use of cardioplegia and cardiopulmonary bypass (off-pump coronary artery bypass graft surgery). Avoiding the potential damaging effects of cardiopulmonary bypass and keeping a nearly continuous perfusion in the coronary arteries of the beating heart have been postulated to offer a better protection of the myocardium with a better outcome and to reduce the perioperative morbidity. Aims: If right ventricular dysfunction is known to occur after conventional coronary artery bypass graft surgery, nothing is known about right ventricular function after off-pump coronary artery bypass graft surgery. Therefore we performed two prospective, randomised, controlled trials to assess and compare the short-term and medium-term effects of conventional and off-pump coronary artery bypass graft surgery on the global and regional right ventricular function. We used transoesophageal and transthoracic echocardiography as investigating tools of right ventricular systolic and diastolic function. Materials and Methods: Fifty consecutive patients scheduled for elective coronary bypass graft surgery and for whom the surgeon regarded off-pump and on-pump techniques as equally suitable were randomised. We performed a transthoracic echocardiography the day before surgery and 3 months after surgery, and a transoesophageal echocardiography just before opening and just after closure of the sternum. Results: Just after closure of the sternum, we could not observe a better protection of the right ventricular function by the off-pump surgery. Cardiac index and right ventricular ejection fraction were equally preserved in the 2 groups. Systolic and diastolic myocardial function (investigated by Tissue Doppler imaging) was impaired only in the off-pump group, but the intergroup difference was not statistically significant. Three months after surgery, there were no differences between the 2 groups: global right ventricular systolic function was equally preserved and right ventricular systolic and diastolic myocardial function equally impaired. Conclusions: These 2 studies do not allow for concluding that off-pump coronary artery bypass graft surgery would better preserve right ventricular systolic and diastolic function than conventional coronary artery bypass graft surgery, just after surgery or 3 months later. In any event, our studies provided the opportunity to acquire experience in systematically evaluating the right ventricle using transoesophageal echocardiography. / Introduction: La dysfonction ventriculaire droite après chirurgie coronaire est un phénomène bien connu. L'utilisation d'un circuit artificiel ainsi que d'une solution de cardioplégie pendant la circulation extra-corporelle (CEC) (chirurgie coronaire classique) a été évoquée comme origine possible de cette dysfonction. Une chirurgie sur cœur battant (chirurgie coronaire sans CEC) est actuellement possible grâce à l'utilisation de stabilisateurs cardiaques (Octopus ou Starfish®). Ce type de chirurgie sans CEC permet d'éviter l'utilisation de la CEC et de solutions de cardioplégie et d'en supprimer ainsi les effets délétères. Elle permet également de maintenir une perfusion quasi continue des artères coronaires. Ces différents éléments ont été évoqués comme offrant une meilleure protection myocardique ainsi qu'un meilleur devenir des patients, et comme pouvant réduire la morbidité périopératoire. Buts : La survenue d'une dysfonction ventriculaire droite après chirurgie coronaire classique est un phénomène bien connu, par contre nous savons peu de chose sur la fonction ventriculaire droite après chirurgie coronaire sans CEC. Pour cette raison, nous avons entrepris deux études prospectives, randomisées et contrôlées afin d'étudier et de comparer les effets à court et moyen terme de la chirurgie coronaire classique et sans CEC. Nous avons utilisé l'échographie cardiaque transthoracique et transœsophagienne comme outil de mesure de la fonction systolique et diastolique du ventricule droit. Matériel et Méthode : Nous avons randomisé cinquante patients consécutifs, programmés pour une chirurgie coronaire élective et pour laquelle le chirurgien estimait qu'une chirurgie sans CEC était aussi appropriée qu'une chirurgie avec CEC. Une échographie cardiaque transthoracique était réalisée la veille de l'intervention ainsi que 3 mois plus tard, une échographie transoesophagienne était réalisée juste avant l'ouverture et après la fermeture du sternum. Résultats : Juste après la fermeture du sternum, la fonction ventriculaire droite dans le groupe sans CEC n'était pas mieux protégée que dans le groupe avec CEC. L'index cardiaque et la fraction d'éjection ventriculaire droite étaient préservés de manière équivalente dans les 2 groupes. La fonction régionale systolique et diastolique du ventricule droit (étudiée par Doppler tissulaire) n'était altérée de manière significative que dans le groupe sans CEC, mais la différence intergroup n'était pas statistiquement significative. A 3 mois également, les 2 groupes ne différaient pas : la fonction systolique globale du ventricule droit était préservée de manière équivalente ; la fonction régionale systolique et diastolique du ventricule droit était altérée de manière équivalente. Conclusions : Ces 2 études ne nous permettent pas de conclure à une meilleure protection de la fonction systolique et diastolique ventriculaire droite par la chirurgie coronaire sans CEC, que ce soit juste en fin de chirurgie ou 3 mois plus tard. D'autre part, ces études nous ont permis d'acquérir de l'expérience dans l'analyse systématique du ventricule droit par échographie cardiaque transoesophagienne.

Background: Elevated blood glucose in patients undergoing cardiac surgery pose increased risks of sternal incision infections, kidney disease, irregular heartbeats, extended hospital stays, and death. Elevated blood glucose also increases the costs of healthcare from prolonged lengths of stay and increased complications. The Surgical Care Improvement Project (SCIP) #4 performance measure is used to evaluate achievement of a target blood glucose control < 200 milligram/deciliter (mg/dl) post cardiac surgery on postoperative days 1 and 2. In the institution where this study was carried out, blood sugar control in the cardiac surgery patient has presented a challenge. Purpose: The purpose of this practice inquiry was to identify patient characteristics and outcomes in cardiac surgery patients who met the SCIP #4 performance measure versus those patients who did not. Methods: A retrospective nested case-control design was used. Risk factors for postoperative hyperglycemia and in-hospital outcomes were compared between cardiac surgery patients who were SCIP #4 met defined as 6AM BG ≤ 200 mg/dl on postoperative days 1 and 2 and those that were SCIP #4 not met, defined as 6AM BG > 200 mg/dl on postoperative days 1 or 2. Results: Results from this study showed that preoperative hemoglobin AIC and history of diabetes were two major contributors for SCIP #4 not-met status. There was a trend towards a longer length of stay in the SCIP #4 not met group as compared to the met group (9.01 ± 7.33 versus 7.30 ± 4.93 days, respectively; p = . 096). Mortality was 3 times more prevalent in the SCIP #4 not met than the met group (6.2% versus 2.1%, respectively); however, this different did not reach statistical significance (p = .129). Renal failure was four-fold more frequent in patients who were SCIP #4 not-met than who were SCIP #4 met (13.6% vs. 4.1%, respectively; p = 0.003). Conclusions: Results from this study showed that SCIP #4 not met is associated with development of postoperative renal failure in the hospital and a trend towards longer length of stay. History of diabetes and preoperative hemoglobin AIC level should be taken into consideration when evaluating strategies for managing hyperglycemia. Future research is needed to study the relationship between SCIP #4 met status and long-term outcomes. The use of preoperative hemoglobin A1C to identify patients at high risk for uncontrolled postoperative glucose and plan effective glucose control should be studied. Such study may include implementing intravenous insulin on all patients with diabetes and elevated hemoglobin A1C levels and comparing the short and long term outcomes.

No description available.

No description available.

Magister Scientiae (Physiotherapy) - MSc(Physio) / An increase of cardiac surgeries globally has been associated with an increasing number of people with cardiovascular disease in both developed and developing countries. Following cardiac surgery, pulmonary complications are an important cause of morbidity leading to significant prolonged hospitalisation, mortality and overall hospital costs. Physiotherapists have been part of cardiac multidisciplinary team playing a role in prevention and managing respiratory complications post-operatively. Numbers of studies have investigated on the efficacy of physiotherapy interventions in managing patients following cardiac surgery. However, there is no consensus in the literature with regards to intensity, duration of the session and content of therapy in this specialised area of cardio-pulmonary. These variations of physiotherapy intervention have made difficult to find agreement on the necessity of physiotherapy care in the post-operative management of patients following cardiac surgery. To date, however, there have been limited or no studies done on the role of physiotherapy in the Cardiac Unit setting. Thus, the aim of the study was to investigate the role of physiotherapy in the post-operative management of patients following cardiac surgery at Muhimbili National Hospital (MNH), Tanzania. An explanatory sequential mixed method study design was used. A descriptive retrospective study design was chosen for the quantitative phase using a convenient sample of all 105 patients’ records operated from January 2010 to 31st December 2013. With regards to the qualitative phase, 2 Cardiac Surgeons and 10 Physiotherapists working at MNH were conveniently sampled to explore their perceptions on the post-operative role of physiotherapy in the management of patients following cardiac surgery at MNH. Ethical clearance was obtained from the University of the Western Cape and Muhimbili National Hospital to conduct the study. Anonymity and confidentiality was ensured for all participants and their participation was voluntary. They were allowed to withdraw from the study anytime without any negative consequences. Following ethical issues; quantitative data (i.e. profile and process of care of patients) was collected by means of a data extraction sheet while the two separate semi-structured interview guides were used for qualitative data. A total of 105 patients’ records were obtained. Quantitative data was analysed using SPSS 22.0 version. A descriptive statistics was used. The mean age of the study sample was 30.6 (SD=10.5). More than half (54.3%) were females and males 45.7% of the sample. The results show that Rheumatic Heart Disease (RHD) accounted for the majority (74.3%) of cardiac diseases. Double valve repair accounted for 71.4%. A decline in the number of surgeries performed were noted from 2010 (48.6%) to 2013 (10.5%). The mean number of days spent in Intensive Care Unit (ICU) were 6.4 (SD=5.3) and in the ward 12.2 (SD=7.8). A total of 21.4% of the sample developed post-operative complications and 10.5% of the total sample died. A substantial number of patients (77.7%) were referred for physiotherapy treatment post-operatively, with most of these referrals (70.0%) on the first day post-operatively. The majority (37.8%) of the patients received 3 physiotherapy sessions in the ICU with most of these patients (79.3%) being seen once a day in the ICU and (65.8%) in the ward. Physiotherapists prescribed (53.7%) a combination of breathing exercises, active limb mobilisation, incentive spirometry and progressive ambulation in the ICU. A combination of breathing exercises, active limb mobilisations, endurance training and posture correction was frequently (89.5%) prescribed in the ward. Content analysis was used to analyse qualitative data. Cardiac Surgeons were aware of the role of Physiotherapists on the post-operative management of patients following cardiac surgery. They also identified shortcomings on the side of Physiotherapists’ in terms of poor co-operation, inadequate skills and a lack of motivation to work in the Cardiac Unit. On the other hand, Physiotherapists revealed that there was communication breakdown between them and Cardiac Surgeons. They added that they were not motivated to work in the Cardiac Unit due to their inadequate skills in the area of investigation, training and lack of working facilities. Although they had consensus on different techniques, they had variations on the application procedure, intensity and frequency. Cardiac Surgeons and Physiotherapists agreed that hospital management should motivate Physiotherapists by opening a Physiotherapy Unit within the Cardiac Complex and train Physiotherapists in the area of cardio-pulmonary. From these findings it can be concluded that, poor communication and lack of trained Physiotherapists in the field of cardio-pulmonary is a setback which need to be addressed. Also, lack of standard treatment procedure among Physiotherapists brings variations in this world of evidence based practice.

No description available.

Cardiac post-surgery inpatients lack the amount and quality of sleep needed for optimal recovery. I aimed to investigate the non-pharmacological sleep promotion practices used by nurses and the factors that influence their use. Guided by the Theoretical Domains Framework, I developed and administered a survey to registered nurses working in the Cardiac Intensive Care Unit and the cardiac surgery ward in one cardiac centre. Findings revealed that common sleep promotion practices included orientating inpatients to the room (n=88, 96.7%), and providing additional bedding (n=86, 96.6%). The most common enablers were knowledge regarding its benefits (n=72, 100%) and an understanding of its importance (n=77, 98.7%); the most common barriers were an absence of recognition from important healthcare professionals (n=61, 85.9%) and having competing priorities (n=60, 83.3%). These findings can be used in the development of interventions to promote nurses’ use of sleep promotion practices and to improve inpatients’ sleep quality.