Ultrasound-guided pudendal nerve block in cats undergoing perineal urethrostomy: a prospective, randomised, investigator-blind, placebo-controlled clinical trial

The objective of this study was to evaluate the clinical usefulness, in terms of analgesic efficacy and safety, of ultrasound-guided pudendal nerve block performed with bupivacaine in cats undergoing perineal urethrostomy. Eighteen client-owned male cats scheduled for perineal urethrostomy were enrolled in the study and assigned to one of two treatment groups. The pudendal nerve block was performed under general anaesthesia as described elsewhere, with 0.3 ml/kg of either saline (group C) or 0.5% bupivacaine (group B) - the total injection volume being split equally on the two sites of injection (left and right). Intra-operatively, assessment of nociception was based on the rescue analgesics requirement, as well as on the evaluation of changes in physiological parameters in comparison with the baseline values. Post-operative pain assessment was performed using three different pain scales at recovery and then 1, 2 and 3 h after recovery. Cats in group B showed lower heart rates and required fewer analgesics during surgery than group C. Post-operatively, group B had lower pain scores and needed less rescue buprenorphine than group C. Iatrogenic block-related complications were not observed. In conclusion, the ultrasound-guided pudendal nerve block can be considered clinically useful in feline medicine as it provides reliable analgesia in cats undergoing perineal urethrostomy.

Endoscopically assisted nerve decompression of rare nerve compression syndromes at the upper extremity

BACKGROUND Besides carpal tunnel and cubital tunnel syndrome, other nerve compression or constriction syndromes exist at the upper extremity. This study was performed to evaluate and summarize our initial experience with endoscopically assisted decompression. MATERIALS AND METHODS Between January 2011 and March 2012, six patients were endoscopically operated for rare compression or hour-glass-like constriction syndrome. This included eight decompressions: four proximal radial nerve decompressions, and two combined proximal median nerve and anterior interosseus nerve decompressions. Surgical technique and functional outcomes are presented. RESULTS There were no intraoperative complications in the series. Endoscopy allowed both identifying and removing all the compressive structures. In one case, the proximal radial neuropathy developed for 10 years without therapy and a massive hour-glass nerve constriction was observed intraoperatively which led us to perform a concurrent complementary tendon transfer to improve fingers and thumb extension. Excellent results were achieved according to the modified Roles and Maudsley classification in five out of six cases. All but one patient considered the results excellent. The poorest responder developed a CRPS II and refused post-operative physiotherapy. CONCLUSION Endoscopically assisted decompression in rare compression syndrome of the upper extremity is highly appreciated by patients and provides excellent functional results. This minimally invasive surgical technique will likely be further described in future clinical studies.

Early re-do surgery for glioblastoma is a feasible and safe strategy to achieve complete resection of enhancing tumor.

BACKGROUND Complete resection of enhancing tumor as assessed by early (<72 hours) postoperative MRI is regarded as the optimal result in glioblastoma surgery. As yet, there is no consensus on standard procedure if post-operative imaging reveals unintended tumor remnants. OBJECTIVE The current study evaluated the feasibility and safety of an early re-do surgery aimed at completing resections with the aid of 5-ALA fluorescence and neuronavigation after detection of enhancing tumor remnants on post-operative MRI. METHODS From October 2008 to October 2012 a single center institutional protocol offered a second surgery within one week to patients with unintentional incomplete glioblastoma resection. We report on the feasibility of the use 5-ALA fluorescence guidance, the extent of resection (EOR) rates and complications of early re-do surgery. RESULTS Nine of 151 patients (6%) with glioblastoma resections had an unintentional tumor remnant with a volume >0.175 cm(3). 5-ALA guided re-do surgery completed the resection (CRET) in all patients without causing neurological deficits, infections or other complications. Patients who underwent a re-do surgery remained hospitalized between surgeries, resulting in a mean length of hospital stay of 11 days (range 7-15), compared to 9 days for single surgery (range 3-23; p=0.147). CONCLUSION Our early re-do protocol led to complete resection of all enhancing tumor in all cases without any new neurological deficits and thus provides a similar oncological result as intraoperative MRI (iMRI). The repeated use of 5-ALA induced fluorescence, used for identification of small remnants, remains highly sensitive and specific in the setting of re-do surgery. Early re-do surgery is a feasible and safe strategy to complete unintended subtotal resections.

The Impact of Pre-Operative Malperfusion on Outcome in Acute Type A Aortic Dissection: Results From the GERAADA Registry

BACKGROUND Malperfusion adversely affects outcomes in patients with acute type A aortic dissection, but reliable quantitative data are lacking. OBJECTIVES The aim of this study was to analyze the impact of various forms of malperfusion on early outcome. METHODS A total of 2,137 consecutive patients enrolled in GERAADA (German Registry for Acute Aortic Dissection Type A) who underwent surgery between 2006 and 2010, of whom 717 (33.6%) had any kind of pre-operative malperfusion, were retrospectively analyzed. RESULTS All-cause 30-day mortality was 16.9% and varied substantially according to the number of organ systems affected by malperfusion (none, 12.6%; 1 system, 21.3%; 2 systems, 30.9%; 3 systems, 43.4%; p < 0.001). Pre-operative cerebral malperfusion, comatose state, peripheral malperfusion, visceral malperfusion, involvement of supra-aortic branches, coronary malperfusion, and renal malperfusion were all independent predictors of developing any post-operative malperfusion syndrome. When survival was considered, age, peripheral malperfusion, involvement of supra-aortic branches, coronary malperfusion, spinal malperfusion, a primary entry in the descending aorta, and pre-operative comatose state were independent predictors, again with increasing significance. CONCLUSIONS Malperfusion remains a severe clinical condition with strong potential for adverse outcomes in patients undergoing surgery for acute type A aortic dissection. The GERAADA registry suggests that the impact of the number of organs involved and the type of malperfusion on outcome differs substantially. Introducing an appropriate classification system, such as "complicated" and uncomplicated" acute type A aortic dissection, might help predict individual risk as well as select a surgical strategy that may quickly resolve malperfusion.

Minimally invasive approach to lumbosacral decompression in a cadaveric canine model

AIMS To determine efficacy of a minimally invasive (MI) surgical approach using a human MI lumbar retractor for canine lumbosacral dorsal laminectomy and partial discectomy and to compare this technique to the standard open surgical (OS) approach. METHODS Lumbosacral dorsal laminectomy and partial discectomy was performed on 16 large-breed canine cadavers using either a standard OS (n=8) or MI (n=8) approach. Skin and fascial incision length, procedure time, and intraoperative complications were recorded. Postoperatively specimens were evaluated for laminectomy and discectomy dimensions, and visible damage to the cauda equina and exiting nerve roots. RESULTS Median length of skin and fascial incisions in the OS group were longer than in the MI group (p<0.001). Median laminectomy length was similar between both approaches (p=0.234) but width was greater for the MI than OS approach (p=0.002). Both approaches achieved similar partial discectomy width (p=0.279). Overall surgical time was longer for MI approaches compared to OS, with a median of 18.5 (min 15.5, max 21.8) minutes for MI compared to 14.6 (min 13.1, max 16.9) minutes for OS (p=0.001). CONCLUSIONS The MI approach reduced incision lengths while retaining comparable laminectomy and discectomy dimensions. For this in vitro model the MI approach required more time to complete, but this difference may not be relevant in clinical cases. CLINICAL RELEVANCE Dogs undergoing lumbosacral dorsal laminectomy are commonly large-breed dogs. The traditional open approach requires a large skin incision and soft tissue dissection, especially in overweight animals. A MI approach accomplishing the same surgical result while minimising soft tissue trauma could reduce post-operative pain and recovery time, and may lower wound-related complications. Clinical studies are needed to confirm postoperative benefit and assess operating times in vivo.

Use of a perineural coiled catheter at the sciatic nerve in dogs after tibial plateau levelling osteotomy – preliminary observations

The analgesic effects of peripheral nerve blocks can be prolonged with the placement of perineural catheters allowing repeated injections of local anaesthetics in humans. The objectives of this study were to evaluate the clinical suitability of a perineural coiled catheter (PCC) at the sciatic nerve and to evaluate pain during the early post-operative period in dogs after tibial plateau levelling osteotomy. Pre-operatively, a combined block of the sciatic and the femoral nerves was performed under sonographic guidance (ropivacaine 0.5%; 0.3 mL kg−1 per nerve). Thereafter, a PCC was placed near the sciatic nerve. Carprofen (4 mg kg−1 intravenously) was administered at the end of anaesthesia. After surgery, all dogs were randomly assigned to receive four injections of ropivacaine (group R; 0.25%, 0.3 mL kg−1) or NaCl 0.9% (group C; 0.3 mL kg−1) every 6 h through the PCC. Pain was assessed by use of a visual analogue scale (VAS) and a multi-dimensional pain score (4Avet) before surgery (T-1), for 390 min (T0, T30, T60, T120, T180, T240, T300, T360 and T390) as well as 1 day after surgery (Day 1). Methadone (0.1 mg kg−1) was administered each time the VAS was ≥40 mm or the 4Avet was ≥5. At T390 dogs received buprenorphine (0.02 mg kg−1). Data were compared using Mann–Whitney rank sum tests and repeated measures analysis of variance. Regardless of group allocation, 55% of dogs required methadone. VAS was significantly lower at T390 (P = 0.003), and at Day 1 (P = 0.002) and so was 4Avet at Day 1 (P = 0.012) in group R than in group C. Bleeding occurred in one dog at PCC placement and PCC dislodged six times of 47 PCCs placed. Minor complications occurred with PCC but allowed four repeated administrations of ropivacaine or saline over 24 h in 91.5% of the cases.

Supplemental cardioplegia immediately before graft implantation may improve early post-transplantation outcome

Gebiet: Chirurgie Abstract: Background: Preservation of cardiac grafts for transplantation is not standardized and most centers use a single administration of crystalloid solution at the time of harvesting. We investigated possible benefits of an additional dose of cardioplegia dispensed immediately before implantation. – – Methods: Consecutive adult cardiac transplantations (2005?2012) were reviewed. Hearts were harvested following a standard protocol (Celsior 2L, 4?8°C). In 2008, 100 ml crys-talloid cardioplegic solution was added and administered immediately before implanta-tion. Univariate and logistic regression analyses were used to investigate risk factors for post-operative graft failure and mid-term outcome. – – Results: A total of 81 patients, 44 standard (?Cardio???) vs. 37 with additional cardiople-gia (?CardioC?) were analyzed. Recipients and donors were comparable in both groups. CardioC patients demonstrated a reduced need for defibrillation (24 vs. 48%, p D0.03), post-operative ratio of CK-MB/CK (10.1_3.9 vs. 13.3_4.2%, p D0.001), intubation time (2.0_1.6 vs. 7.2_11.5 days, p D0.05), and ICU stay (3.9_2.1 vs. 8.5_7.8 days, p D0.001). Actuarial survival was reduced when graft ischemic time was >180 min in Cardio?? but not in CardioC patients (p D0.033). Organ ischemic time >180 min (OR: 5.48, CI: 1.08?27.75), donor female gender (OR: 5.84, CI: 1.13?33.01), and recipient/donor age >60 (OR: 6.33, CI: 0.86?46.75), but not the additional cardioplegia or the observation period appeared independent predictors of post-operative acute graft failure. – – Conclusion: An additional dose of cardioplegia administered immediately before implan-tation may be a simple way to improve early and late outcome of cardiac transplantation, especially in situations of prolonged graft ischemia.A large, ideally multicentric, randomized study is desirable to verify this preliminary observation.

Complications of misoprostol and other abortion induction methods in the developing world: A systematic review

OBJECTIVE: To systematically review published literature to examine the complications associated with the use of misoprostol and compare these complications to those associated with other forms of abortion induction. ^ DATA SOURCES: Studies were identified through searches of medical literature databases including Medline (Ovid), PubMed (NLM), LILACS, sciELO, and AIM (AFRO), and review of references of relevant articles. ^ STUDY SELECTION AND METHODS: A descriptive systematic review that included studies reported in English and published before December 2012. Eligibility criteria included: misoprostol (with or without other methods) and any other method of abortion in a developing country, as well as quantitative data on the complication of each method. The following is information extracted from each study: author/year, country/city, study design/study sample, age range, setting of data collection, sample size, the method of abortion induction, the number of cases for each method, and the percentage of complications with each method. RESULTS: A total of 4 studies were identified (all in Latin America) describing post-abortion complications of misoprostol and other methods in countries where abortion is generally considered unsafe and/or illegal. The four studies reported on a range of complications including: bleeding, infection, incomplete abortion, intense pelvic pain, uterine perforation, headache, diarrhea, nausea, mechanical lesions, and systemic collapse. The most prevalent complications of misoprostol-induced abortion reported were: bleeding (7-82%), incomplete abortion (33-70%), and infection (0.8-67%). The prevalence of these complications reported from other abortion methods include: bleeding (16-25%), incomplete abortion (15-82%), and infection (13-50%). ^ CONCLUSION: The literature identified by this systematic review is inadequate for determining the complications of misoprostol used in unsafe settings. Abortion is considered an illicit behavior in these countries, therefore making it difficult to investigate the details needed to conduct a study on abortion complications. Given the differences between the reviewed studies as well as a variety of study limitations, it is not possible to draw firm conclusions about the rates of specific-abortion related complications.^

Injetor intravascular de CO2: estudo in vivo de viabilidade inicial do dispositivo e de qualidade de imagem

INTRODUÇÃO: Durante procedimentos endovasculares, estão presentes os riscos relacionados ao uso dos contrastes iodados, tais como a nefropatia por contraste, uma vez que é fundamental o emprego de um meio de contraste para a obtenção das imagens radiológicas vasculares. A injeção intravascular de gás CO2 purificado é reconhecidamente uma alternativa relativamente mais segura ao contraste iodado, contudo, seu manuseio artesanal pode também trazer dificuldades técnicas e riscos aos pacientes. Para contemplar estas questões, foi desenvolvido o protótipo de um injetor intravascular de CO2 medicinal, microprocessado, dedicado à obtenção de imagens angiográficas. OBJETIVOS: Realizar os testes de viabilidade técnica inicial do protótipo em modelo in vivo. MÉTODOS: Realizar a angioplastia da artéria renal esquerda de 10 porcos, divididos em 2 grupos: Grupo 1 (n=5) injeção de contraste iodado, Grupo 2 (n=5) injeção de CO2 através do protótipo. Monitorização clínica e laboratorial dos animais no pré, intra e pós-operatório, com exames de função renal na véspera e 48h após os procedimentos e 3 gasometrias arteriais seriadas no intra-operatório. Observação clínica foi mantida por 48h no pós- operatório. RESULTADOS: Os procedimentos de angioplastia com CO2 foram realizados com sucesso técnico de 100%, sem necessidade de complementação com injeção de contraste iodado no Grupo 2. Não foram identificadas falhas no protótipo em funcionamento. Não foram identificadas alterações clínicas ou radiológicas sugestivas de contaminação por ar ambiente do sistema de CO2 e nem alterações laboratoriais nos animais. As imagens angiográficas obtidas no Grupo 2 foram consideradas, numa avaliação subjetiva, relativamente inferiores às imagens obtidas no Grupo 1. DISCUSSÃO: A qualidade inferior de imagem no Grupo 2 pode ser atribuída ao equipamento de fluoroscopia utilizado, com software desatualizado em relação aos equipamentos atuais, que incluem pré-configurações para angiografia com CO2; no entanto, ainda assim todos os procedimentos propostos no Grupo 2 foram realizados com sucesso técnico, o que nos leva a classificar as imagens deste grupo 2 como satisfatórias. O manuseio do aparelho mostrou-se ágil e eficiente, com a programação dos parâmetros sendo realizada com facilidade através do visor \"touch screen\", comparativamente superior ao método artesanal de injeção de CO2 com seringas em selo d\'água. CONCLUSÕES: O protótipo do aparelho injetor intravascular de CO2 funcionou de forma adequada durante os testes e as imagens obtidas permitiram a compleição com sucesso dos procedimentos. Portanto, os resultados positivos obtidos sugerem que o equipamento é tecnicamente viável

Hiperparatiroidismo primário em doentes jovens

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2014

Two knees or not two knees? Patient costs and outcomes following bilateral and unilateral total knee joint replacement surgery for OA

Aims: This study aims to address medical and non-medical direct costs and health outcomes of bilateral and unilateral total knee replacement from the patients' perspective during the first year post-surgery. Methods: Osteoarthritis patients undergoing primary unilateral total knee or bilateral total knee replacement (TKR) surgery at three Sydney hospitals were eligible. Patients completed questionnaires pre-operatively to record expenses during the previous three months and health status immediately prior to surgery. Patients then maintained detailed prospective cost diaries and completed SF-36 and WOMAC Index each three months for the first post-operative year. Results: Pre-operatively, no significant differences in health status were found between patients undergoing unilateral TKR and bilateral TKR. Both unilateral and bilateral TKR patients showed improvements in pain, stiffness and function from pre-surgery to 12 months post-surgery. Patients who had bilateral TKR spent an average of 12.3 days in acute hospital and patients who had unilateral TKR 13.6 days. Totally uncemented prostheses were used in 6% of unilateral replacements and 48% of bilateral replacements. In hospital, patients who had bilateral TKR experienced significantly more complications, mainly thromboembolic, than patients who had unilateral TKR. Regression analysis showed that for every one point increase in the pre-operative SF-36 physical score (i.e. improving physical status) out-of-pocket costs decreased by 94%. Out-of-pocket costs for female patients were 3.3 times greater than for males. Conclusion: Patients undergoing bilateral TKR and unilateral TKR had a similar length of stay in hospital and similar out-of-pocket expenditures. Bilateral replacement patients reported better physical function and general health with fewer health care visits one year post procedure. Patients requiring bilateral TKR have some additional information to aid their decision making. While their risk of peri-operative complications is higher, they have an excellent chance of good health outcomes at 12 months and are not going to be doubly 'out-of-pocket' for the experience. (C) 2004 OsteoArthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Postoperative analgesic requirements - total laparoscopic hysterectomy versus vaginal hysterectomy

Background: There is limited information available on the requirement for postoperative analgesic drugs in patients submitted to total laparoscopic hysterectomy (TLH) compared with patients undergoing vaginal hysterectomy (VH). Aim: To compare the postoperative analgesic requirements in patients who underwent a TLH with patients who had a VH. Methods: Chart review of 53 patients who had TLH and 47 who had VH and were seen postoperatively by an acute pain management service in order to assess postoperative analgesic requirements. Patient controlled analgesia (PCA) was part of the standard protocol for postoperative pain management. Analgesic requirement was recorded as the mean doses of morphine and number of days that patients used non-steroidal anti-inflammatory drugs (NSAIDs), oxycodone and tramadol. Results: The requirement for total morphine was approximately half the dose in patients who had a TLH (10.8 +/- 12.6 mg) compared with patients who had a VH (19.4 +/- 21.9 mg) (P 0.017). The length of use of NSAIDs was significantly reduced in patients who had undergone a TLH (2.0 +/- 0.95 days) as compared with patients who had a VH (2.85 +/- 1.1 days) (P < 0.0001). Conclusions: Patients submitted to TLH require less postoperative analgesic drugs when compared with patients who had VH. Prospective randomised trials are warranted to compare analgesic requirements between patients submitted to TLH and VH.

Circadian rhythm disruption and post-surgical recovery

Circadian rhythms, patterns of each twenty-four hour period, are found in most bodily functions. The biological cycles of between 20 and 28 hours have a profound effect on an individual's mood, level of performance, and physical well being. Loss of synchrony of these biological rhythms occurs with hospitalization, surgery and anesthesia. The purpose of this comparative, correlational study was to determine the effects of circadian rhythm disruption in post-surgical recovery. Data were collected during the pre-operative and post-operative periods in the following indices: body temperature, blood pressure, heart rate, urine cortisol level and locomotor activity. The data were analyzed by cosinor analysis for evidence of circadian rhythmicity and disruptions throughout the six day study period which encompassed two days pre-operatively, two days post-operatively, and two days after hospital discharge. The sample consisted of five men and five women who served as their own pre-surgical control. The surgical procedures were varied. Findings showed evidence of circadian disruptions in all subjects post-operatively, lending support for the hypotheses.

Benefits of laparoscopic colorectal surgery in the geriatric patient

Background. Our aim is the retrospective valuation of results in over 75 year-old patients, with colorectal cancer, treated with laparoscopic and laparotomic surgery, considering how laparoscopic surgery has improved these patients’ outcome. Patients and methods. We took all over 75 year-old patients, affected by colorectal cancer, treated with colectomy. Patients has been divided into two groups: laparotomy group and laparoscopy group. Data concerning patients, i.e., age, sex, BMI, ASA, comorbidities, were collected with data concerning the operation (surgical time, conversion percentage). Postoperative outcomes – i.e., gas evacuation, bowel movements, solid and liquid feeding, need to ICU, complications, re-surgery, hospitalization and type of discharge, mortality – were evaluated. Results. A total of 145 patients are included: laparotomy 80 and laparoscopy 51. Two groups are homogeneous for age, sex, BMI, ASA, comorbidities. Surgical times are the same. Need to Intesive Care Unit (ICU) is lower in laparoscopy. Gas evacuation and bowel movements are earlier in laparoscopy. Liquid and solid diet is earlier in laparoscopy. Hospitalization was earlier after laparoscopy. Discharge at home is more frequent in laparoscopy. Major and minor complications are lower in laparoscopy. Post-operative mortality is lower in laparoscopy. Conclusions. Laparoscopy improves over 75 year-old patients’ outcomes, after elective surgery for colorectal cancer. Surgery trauma, anaesthesia, nutritional and hemodynamic alterations, are factors that break the old patients’ fragile physiologic balance. Less traumatic surgery improves old patients’ outcomes.

An investigation of the clinical utility of preoperative cardiopulmonary exercise testing in patients undergoing major pancreatic surgery

Pancreaticoduodenectomy with or without adjuvant chemotherapy remains the only modality of possible cure in patients with cancer involving the head of the pancreas and the periampullary region. While mortality rates after pancreaticoduodenectomy have improved considerably over the course of the last century, morbidity remains high. Patient selection is of paramount importance in ensuring that major surgery is offered to individuals who will most benefit from a pancreaticoduodenectomy. Moreover, identifying preoperative risk factors provides potential targets for prehabilitation and optimisation of the patient's physiology before undertaking surgery. In addition to this, early identification of patients who are likely to develop postoperative complications allows for better allocation of critical care resources and more aggressive management high risk patients. Cardiopulmonary exercise testing is becoming an increasingly popular tool in the preoperative risk assessment of the surgical patient. However, very little work has been done to investigate the role of cardiopulmonary exercise testing in predicting complications after pancreaticoduodenectomy. The impact of jaundice, systemic inflammation and other preoperative clinicopathological characteristics on cardiopulmonary exercise physiology has not been studied in detail before in this cohort of patients. The overall aim of the thesis was to examine the relationships between preoperative clinico-pathological characteristics including cardiopulmonary exercise physiology, obstructive jaundice, body composition and systemic inflammation and complications and the post-surgical systemic inflammatory response in patients undergoing pancreaticoduodenectomy. Chapter 1 reviews the existing literature on preoperative cardiopulmonary exercise testing, the impact of obstructive jaundice, perioperative systemic inflammation and the importance of body composition in determining outcomes in patients undergoing major surgery with particular reference to pancreatic surgery. Chapter 2 reports on the role of cardiopulmonary exercise testing in predicting postoperative complications after pancreaticoduodenectomy. The results demonstrate that patients with V˙O2AT less than 10 ml/kg/min are more likely to develop a postoperative pancreatic fistula, stay longer in hospital and less likely to receive adjuvant therapy. These results emphasise the importance of aerobic fitness to recover from the operative stress of major surgery without significant morbidity. Cardiopulmonary exercise testing may prove useful in selecting patients for intensive prehabilitation programmes as well as for other optimisation measures to prepare them for major surgery. Chapter 3 evaluates the relationship between cardiopulmonary exercise physiology and other clinicopathological characteristics of the patient. A detailed analysis of cardiopulmonary exercise test parameters in jaundiced versus non-jaundiced patients demonstrates that obstructive jaundice does not impair cardiopulmonary exercise physiology. This further supports emerging evidence in contemporary literature that jaundiced patients can proceed directly to surgery without preoperative biliary drainage. The results of this study also show an interesting inverse relationship between body mass index and anaerobic threshold which is analysed in more detail in Chapter 4. Chapter 4 examines the relationship between preoperative cardiopulmonary exercise physiology and body composition in depth. All parameters measured at cardiopulmonary exercise test are compared against body composition and body mass index. The results of this chapter report that the current method of reporting V˙O2, both at peak exercise and anaerobic threshold, is biased against obese subjects and advises caution in the interpretation of cardiopulmonary exercise test results in patients with a high BMI. This is particularly important as current evidence in literature suggests that postoperative outcomes in obese subjects are comparable to non-obese subjects while cardiopulmonary exercise test results are also abnormally low in this very same cohort of patients. Chapter 5 analyses the relationship between preoperative clinico-pathological characteristics including systemic inflammation and the magnitude of the postoperative systemic inflammatory response. Obstructive jaundice appears to have an immunosuppressive effect while elevated preoperative CRP and hypoalbuminemia appear to have opposite effects with hypoalbuminemia resulting in a lower response while elevated CRP in the absence of hypoalbuminemia resulted in a greater postoperative systemic inflammatory response. Chapter 6 evaluates the role of the early postoperative systemic inflammatory response in predicting complications after pancreaticoduodenectomy and aims to establish clinically relevant thresholds for C-Reactive Protein for the prediction of complications. The results of this chapter demonstrate that CRP levels as early as the second postoperative day are associated with complications. While post-operative CRP was useful in the prediction of infective complications, this was the case only in patients who did not develop a post-operative pancreatic fistula. The predictive ability of inflammatory markers for infectious complications was blunted in patients with a pancreatic fistula. Chapter 7 summarises the findings of this thesis, their place in current literature and future directions. The results of this thesis add to the current knowledge regarding the complex pathophysiological abnormalities in patients undergoing pancreaticoduodenectomy, with specific emphasis on the interaction between cardiopulmonary exercise physiology, obstructive jaundice, systemic inflammation and postoperative outcomes. The work presented in this thesis lays the foundations for further studies aimed at improving outcomes after pancreaticoduodenectomy through the development of individualised, goal-directed therapies that are initiated well before this morbid yet necessary operation is performed.