Preoperative Supervised Exercise Improves Outcomes After Elective Abdominal Aortic Aneurysm Repair: A Randomized Controlled Trial.

OBJECTIVE: The aim of the study was to assess the impact of a preoperative medically supervised exercise program on outcomes after elective abdominal aortic aneurysm (AAA) repair. BACKGROUND: Functional capacity is an important predictor of postoperative outcomes after elective AAA repair. Improving patients' preoperative fitness with exercise has the potential to positively influence recovery. METHODS: A randomized controlled trial was performed at a tertiary vascular unit. Patients scheduled for open or endovascular AAA repair were randomized to either 6 weeks of preoperative supervised exercise or standard treatment using sealed envelopes. The primary outcome measure was a composite endpoint of cardiac, pulmonary, and renal complications. Secondary outcome measures were 30-day mortality, lengths of hospital and critical care stay, Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, reoperation, and postoperative bleeding. RESULTS: One hundred twenty-four patients were randomized (111 men, mean [SD] age 73 [7] y). Fourteen patients sustained postoperative complications in the exercise group (22.6%), compared with 26 in the nonexercise group (41.9%; P = 0.021). Four patients (2 in each group) died within the first 30 postoperative days. Duration of hospital stay was significantly shorter in the exercise group (median 7 [interquartile range 5-9] vs 8 [interquartile range 6-12.3] d; P = 0.025). There were no significant differences between the groups in the length of critical care stay (P = 0.845), APACHE II scores (P = 0.256), incidence of reoperations (P = 1.000), or postoperative bleeding (P = 0.343). CONCLUSIONS: A period of preoperative supervised exercise training reduces postoperative cardiac, respiratory, renal complications, and length of hospital stay in patients undergoing elective AAA repair.

Comparison of Use of Short Form-36 Domain Scores and Patient Responses for Derivation of Preference-Based SF6D Index to Calculate Quality-Adjusted Life Years in Patients with Intermittent Claudication.

BACKGROUND: The short form 36 (SF36) questionnaire is used for assessment of generic quality of life. Responses to the individual question in SF36 are also used for calculation of the SF6D index score. This score is used for calculation of quality adjusted-life years (QALYs) in economical analyses. As the individual patient questionnaires are not always available for performing systematic reviews and meta-analyses, a new formula has been developed for derivation of SF6D index score from the reported SF36-domain scores. This study aimed to evaluate the validity of this formula for use in patients with intermittent claudication. METHODS: A retrospective review of a prospectively collected database of a randomized controlled trial was performed. A total of 178 patients were recruited. Clinical indicators of ischemia were recorded. All patients completed SF36 questionnaires. Response and domain-based SF6D scores (R-SF6D and D-SF6D) and QALYs were calculated. Correlation and agreement analysis were performed. RESULTS: Response rate was 88% (n = 781) over a 1-year follow-up period. Domain-based SF6D score (mean, 0.684; standard deviation [SD] 0.110) was significantly higher (paired t-test, P = 0.001) than the response-based score (mean, 0.627; SD, 0.110) with a mean difference of 0.056 (95% confidence interval, 0.053-0.060). Mean QALY calculated using D-SF6D score (0.503; SD, 0.116) was also significantly higher than the QALY calculated from the R-SF6D score (0.467; SD, 0.121). Bland-Altman comparison showed strong agreement (limit of agreement -0.167 to 0.054) between the 2 methods with equal variances (Pitman's test, P = 0.629). D-SF6D scores showed stronger correlation with clinical indicators of ischemia (r = 0.246-0.602) compared with that of R-SF6D scores (r = 0.233-0.549). CONCLUSIONS: Domain-based estimation of SF6D score is a valid and reliable method with strong agreement to the gold standard response-based scores in claudicants. However, adjustments may be required in studies using a mixture of D-SF6D and R-SF6D scores for QALY calculation.

Outcomes after open repair of ruptured abdominal aortic aneurysms in octogenarians: a 20-year, single-center experience.

BACKGROUND: The purpose of this study was to evaluate morbidity, mortality, and survival in octogenarians undergoing open repair of ruptured abdominal aortic aneurysms (RAAAs) in comparison to younger patients. METHODS: This investigation was a retrospective analysis of a prospectively maintained database from a tertiary referral center. We included all consecutive RAAA patients who underwent open repair from 1990 to 2011. Univariate and multivariate analyses were used to identify predictors of inferior short- and long-term outcomes. RESULTS: Overall, 463 patients were identified, of whom 138 (30%) were octogenarians (group 2), with a mean age of 84 ± 0.47 years. There were 96 (69%) men and 42 women (31%). There were more women in group 2 (31%) compared with the <80-year-old patients of group 1 (14%) (P < 0.001). The 30-day mortality for group 2 was 43.5% compared with 28.0% for group 1 (P < 0.001). Preoperatively, 63% of group 1 patients presented with shock compared with 65% of those in group 2 (P = 0.751). There was no difference between the two groups in terms of preoperative systolic blood pressure (SBP), duration of operation, and intraoperative blood loss (P > 0.05). Median preoperative hemoglobin (P < 0.001) and creatinine (P = 0.031) levels were significantly different between the groups. There was no significant difference between the two groups in terms of postoperative complications and length of hospital stay. Median long-term survival for octogenarians (group 2) was 5.4 years compared with 12.4 years for the younger patient group (group 1) (P < 0.001). Multivariate analysis identified age as an independent predictor of 30-day mortality (odds ratio [OR] = 1.154, 95% confidence interval [CI] 1.037-1.285) and inferior long-term survival (OR = 1.074, 95% CI 1.011-1.141). History of cigarette smoking also predicted worse long-term outcomes (OR = 3.044, 95% CI 1.318-7.032) as did multiorgan failure in the postoperative course (OR = 1.363, 95% CI 1.080-14.130). CONCLUSIONS: Advanced age is associated with high surgical mortality; however, for octogenarians surviving surgical repair, long-term outcome is acceptable. Therefore, with responsible decision-making, surgical intervention is justifiable in the elderly. Smoking and multiorgan failure were both predictive of worse survival.

Supervised exercise program improves aerobic fitness in patients awaiting abdominal aortic aneurysm repair.

BACKGROUND: Aerobic fitness is an important predictor of postoperative outcome in major surgery. In this study, we assess the effects of a period of preoperative exercise on aerobic fitness as measured by cardiopulmonary exercise testing (CPET) in patients scheduled for abdominal aortic aneurysm (AAA) repair. METHODS: As part of a randomized trial, the first patients recruited in the intervention group were enrolled in a supervised exercise program of six week duration. Treadmill CPET parameters were measured before and after exercise preoperatively for these patients. These parameters were as follows: peak oxygen uptake (VO2 peak), anaerobic threshold (AT), and ventilator equivalents for oxygen and carbon dioxide (VE/VO2 and VE/VCO2, respectively). Total exercise time and the time at which AT was achieved were also recorded. A comparison between pre- and postexercise parameters was made to detect for a possible improvement in aerobic fitness. RESULTS: Twenty patients with AAA (17 men; mean age: 74.9 ± 5.9 years) were included in this study. Thirty-five percent of patients had a history of ischemic heart disease, 25% of obstructive airway disease, and 15% of cerebral vascular events. Seventy percent were previous smokers, and 15% were current smokers. Fifty-five percent of patients were taking aspirin and 75% were undergoing statin therapy. The median (interquartile range) VO2 peak at baseline was 18.2 (15.4-19.9) mL/kg/min, and after exercise was 19.9 (17.1-21.1; P = 0.048). Median AT at baseline was 12.2 (10.5-14.9), and 14.4 (12.3-15.4) after exercise (P = 0.023). Time of exercise tolerated also improved from a median of 379 to 604 sec (P = 0.001). No significant changes were seen in VE/VO2, VE/VCO2, or the time at which AT was achieved. CONCLUSION: This study shows that cardiopulmonary aerobic fitness improves after a period of supervised exercise in patients scheduled for AAA repair. This is justification for a randomized trial to assess whether this affects morbidity and mortality after AAA repair.

Role of pre-operative multiple gated acquisition scanning in predicting long-term outcome in patients undergoing elective abdominal aortic aneurysm repair.

OBJECTIVE: To determine whether resting pre-operative left ventricular ejection fraction (LVEF) estimated by multiple gated acquisition scanning (MUGA) predicts long-term survival in patients undergoing elective abdominal aortic aneurysm (AAA) repair. METHODS: A retrospective study of MUGA scans which were performed to estimate pre-operative resting LVEF in 127 patients [106 (83 %) males, mean age 74 ± 7.6 years] who underwent elective AAA repair over a period of 4 years from March 2007. We compared outcomes and long-term survival between patients who had a pre-operative LVEF ≤ 40 % (Group 1, n = 60) and LVEF > 40 % (Group 2, n = 67). RESULTS: Overall 19 (15 %) patients died during the follow-up period (13 patients in group 1 and 6 patients in group 2). 30-day mortality was 8 %. There was no significant difference between group 1 and 2 in terms of patients' mean age or median length of hospital stay (8 days for both groups, p = 0.61). However, group 2 had more females than group 1(18 vs. 3, p = 0.001). Median survival for patients in group 2 was significantly higher than patients in group 1 (1,258 days vs. 1,000 days, p = 0.03). In a Cox regression model which included age, sex, smoking status and LVEF as covariates, only smoking status and LVEF predicted survival [Hazard ratio (HR) = 1.06, p = 0.04 and HR = 0.93, p = 0.00, respectively]. CONCLUSION: This study shows that there is a role for pre-operative MUGA scan assessment of resting LVEF in predicting long-term survival post elective AAA repair and that the lower the pre-operative LVEF the poorer the long-term outcome.

A randomized placebo controlled trial of the effect of preoperative statin use on matrix metalloproteinases and tissue inhibitors of matrix metalloproteinases in areas of low and peak wall stress in patients undergoing elective open repair of abdominal aortic aneurysm.

BACKGROUND: A double-blind, randomized controlled trial was carried out to study the effects of statins on matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs) in areas of peak and low abdominal aortic aneurysm (AAA) wall stress. METHODS: A total of 40 patients undergoing elective open AAA repair were randomized to receive either atorvastatin 80 mg (n = 20) or placebo (n = 20) for 4 weeks preoperatively. Finite element analysis was used to determine AAA wall stress distribution. Full thickness aortic samples were obtained at surgery from areas of low and peak wall stress, snap-frozen, and stored at -80°C for subsequent MMP-2, -8, and -9 and TIMP-1 and -2 analyses. Statistical analysis was performed using SPSS 16.0 (SPSS Inc, Chicago, IL). RESULTS: Both groups were well matched (p > 0.05) regarding age, gender, comorbidities, and duration of hospital stay. There were no statistically significant differences in levels of MMPs and TIMPs between the statin and placebo group and between areas of low and peak AAA wall stress. CONCLUSION: The short-term use of statins is not associated in reducing levels of MMP 2, 8, and 9 and TIMP-1 and -2 in areas of low and peak wall stress in patients with AAA.

Patients' perspective of functional outcome after elective abdominal aortic aneurysm repair: a questionnaire survey.

BACKGROUND: To evaluate patients' awareness, functional outcome, and satisfaction after abdominal aortic aneurysm (AAA) repair. METHODS: A study-specific questionnaire was developed with collaboration of a multidisciplinary team. Lists of patients who underwent elective open AAA repair and endovascular aneurysm repair (EVAR) between January 2006 and December 2008 were obtained from the departmental database and cross-checked against hospital database for survival status. Emergency AAA repairs were excluded. Study questionnaires were posted to 138 patients (113 open, 25 EVAR) with self-addressed stamped return envelopes. Statistical analysis was performed using SPSS v16.0. RESULTS: Response rate was 89% (n = 123; 102 open, 21 EVAR). Seventy-one percent (n = 88) were unaware of this condition before diagnosis. Ninety-seven percent (n = 120) indicated their understanding of the need for surgery. Ninety-two percent (n = 113) stated that the operation was adequately explained to them. Ninety percent (n = 111) reported full recovery after surgery, with 60% (n = 74) recovering within 6 months. Eighty-seven percent (n = 108) were satisfied with the overall experience, and 85% (n = 105) stated that they would recommend the operation to family and/or friends if required. CONCLUSIONS: There is a lack of awareness regarding AAA in elderly population. However, after being diagnosed, patients understand the implications and are satisfied with the overall results and would recommend AAA repair to family and/or friends if required.

An analysis of relationship between quality of life indices and clinical improvement following intervention in patients with intermittent claudication due to femoropopliteal disease.

OBJECTIVES: To establish the relationship between quality of life (QOL) index scores and clinical indicators of lower limb ischemia. METHODS: One hundred seventy-eight patients (108 men, median age 70 years) with femoropopliteal lesions suitable for angioplasty were recruited. Assessments were performed prior to and at 1, 3, 6, and 12 months following intervention (angioplasty and/or supervised exercise program). Clinical indicators of lower limb ischemia (treadmill walking distances, ankle pressures), generic (SF36, EuroQol), and disease-specific (Kings College VascuQol) quality of life questionnaires were analyzed. Correlation analysis was performed for index scores (SF-6D, EQ-5D, VascuQol) and individual domain scores using nonparametric tests. RESULTS: All clinical indicators of lower limb ischemia and quality of life index scores showed a statistically significant improvement as result of intervention (Friedman test, P < .001). Both generic QOL index scores (SF-6D, EQ-5D) showed moderate but statistically significant correlation (Spearman's rank correlation, P < .001) with treadmill walking distances (SF-6D r = 0.533, EQ-5D r = 0.500) and weak but significant correlation to resting and postexercise ankle-brachial pressure index (SF-6D r = 0.253, EuroQol r = 0.214). Disease-specific index scores (VascuQol) showed similar moderate correlation to treadmill walking distances (r = 0.584, P < .001) and weak but statistically significant correlation with resting and postexercise ABPI (r = 0.377, P < .001). All index scores showed strong and statistically significant (P< .001) correlation with patient-reported walking distance (SF-6D r = 0.604, EQ-5D r = 0.511, VascuQol r = 0.769). All domains of SF36 showed similar correlation with clinical indicators except general health. The strongest correlation was seen with treadmill walking distances in the domains of physical function (r = 0.538) and bodily pain (r = 0.524). CONCLUSION: All generic and disease-specific QOL scores show statistically significant improvement with angioplasty and/or supervised exercise in patients with claudication due to femoropopliteal atherosclerosis. However, the degree of improvement seen in clinical indicators of lower limb ischemia is not reflected in these scores. These findings support the use of composite outcome measures with mandatory, independent assessment of QOL as an independent outcome measure in intervention studies in these patients.

Perioperative, Postoperative, and Long-Term Outcomes Following Open Surgical Repair of Ruptured Abdominal Aortic Aneurysm.

We investigated factors that affected perioperative, postoperative, and long-term outcomes of patients who underwent open emergency surgical repair of ruptured abdominal aortic aneurysms (RAAA). All patients who underwent open emergency surgical repair from 1990 to 2011 were included (463 patients; 374 [81%] male; mean age 74.7 ± 8.7years). Logistic and Cox regression analyses were performed to explore the association of variables with outcomes. Preoperatively, median (interquartile range) hemoglobin was 11.2 (9.5-12.8) g/dL, and median creatinine level was 140 (112-177) µmol/L. Intraoperatively, the median operative time was 2.25 (2-3) hours, and median estimated blood loss was 1.5 (0.5-3) L; 250 (54%) patients required intraoperative inotropes, and a median of 6 (4-8) units of blood was transfused. Median length of hospital stay was 11 (7-20) days. In-hospital mortality rate was 35.6%, and 5-year mortality was 48%. Age, distance traveled, operation duration, postoperative myocardial infarction (MI), and multi-organ failure (MOF) were predictors of in-hospital mortality and long-term outcome. Additionally, postoperative acute renal failure predicted in-hospital mortality. In patients with RAAA undergoing open surgical repair, the strongest predictors of in-hospital mortality and long-term outcome were postoperative MOF and MI and operative duration.

28-Day emergency surgical re-admission rates as a clinical indicator of performance.

With the introduction of clinical governance, the NHS Executive has identified 28-day emergency re-admission rates as a clinical indicator to be used to assess and compare performance between NHS trusts. We undertook a 3-month retrospective audit of patients identified from the trust computer as having been re-admitted as an emergency within 28 days of discharge from the general surgical division. We wanted to examine reasons for re-admission, possible errors in coding and any preventable factors in these patients subsequently re-admitted acutely.

Chylous ascites complicating elective abdominal aortic aneurysm repair: case report and review of treatment options.

INTRODUCTION: Chylous ascitis is a rare complication of abdominal aortic aneurysm (AAA) surgery with only 38 cases reported since the early 70s. Due to their anatomical relation with the abdominal aorta, cisterna chyli injury is more common following open AAA repairs when compared to other surgeries; 81% of all postsurgical chylous ascites reported. CASE PRESENTATION: We present a case of severe chylous ascitis following elective AAA repair in a 76-year-old caucasian male who gradually developed abdominal distension following discharge. A conservative approach was followed by a peritoneovenous shunt insertion, but this had no clinical benefit. The site of chyle leak was identified and ligated at relaparatomy to eventually resolve his ascitis. CONCLUSION: Many reports in literature demonstrate successful conservative measures and highlight the importance of nutritional status in the course of persistent postoperative chylous ascitis. In our experience, complete resolution only came after relaparatomy and repair of leaking lymphatics.

Peak wall stress measurement in elective and acute abdominal aortic aneurysms.

BACKGROUND: Abdominal aortic aneurysm (AAA) rupture occurs when wall stress exceeds wall strength. Engineering principles suggest that aneurysm diameter is only one aspect of its geometry that influences wall stress. Finite element analysis considers the complete geometry and determines wall stresses throughout the structure. This article investigates the interoperator and intraoperator reliability of finite element analysis in the calculation of peak wall stress (PWS) in AAA and examines the variation in PWS in elective and acute AAAs. METHOD: Full ethics and institutional approval was obtained. The study recruited 70 patients (30 acute, 40 elective) with an infrarenal AAA. Computed tomography (CT) images were obtained of the AAA from the renal vessels to the aortic bifurcation. Manual edge extraction, three-dimensional reconstruction, and blinded finite element analysis were performed to ascertain location and value of PWS. Ten CT data sets were analyzed by four different operators to ascertain interoperator reliability and by one operator twice to ascertain intraoperator reliability. An intraclass correlation coefficient was obtained. The Mann-Whitney U test and independent samples t test compared groups for statistical significance. RESULTS: The intraclass correlation coefficient was 0.71 for interoperator reliability and 0.84 for intraoperator reliability. There was no statistically significant difference in the mean (SD) maximal AAA diameter between elective (6.47 [1.30] cm) and acute (7.08 [1.39] cm) patients (P = .073). The difference in PWS between elective (0.67 [0.30] MPa) and acute (1.11 [0.51] MPa) patients (P = .008) was statistically significant, however. CONCLUSION: Interoperator and intraoperator reliability in the derivation of PWS is acceptable. PWS, but not maximal diameter, was significantly higher in acute AAAs than in elective AAAs.

Differential functions of tissue factor in the trans-activation of cellular signalling pathways.

In this study we examined the ability of tissue factor (TF) alone, or in conjunction with factor VIIa, factor Xa and TFPI in activating a number of key signalling pathways associated with cellular growth, stress and differentiation responses in human endothelial cells. We used luciferase reporter systems to demonstrate the activation of p42/44 MAPK by the TF-FVIIa complex, mediated via the PAR1 receptor. TF alone was capable of interacting with the cell surface and was sufficient to activate the JNK-SAPK pathway and subsequently AP-1, but the level of activation was enhanced by the activity of FXa on PAR1 and 2. Furthermore, the phosphorylated form of the transmembrane-cytoplasmic domain of TF was directly responsible for activation of these pathways. CREB activation occurred in response to TF-FVIIa in a non-protease dependent manner but was lowered on addition of FXa. Finally, NFkappaB activation occurred in response to FVIIa or FXa, with the latter exhibiting higher levels of activation. In conclusion, we have shown that TF is capable of activating differing signalling pathways, via more than one mechanism. The differential influence of TF is modified depending on the presence of other coagulation factors and ultimately acts as a deciding factor in the determination of cellular fate.

A nonrandomised controlled trial of endovenous laser therapy and surgery in the treatment of varicose veins.

Endovenous laser therapy (EVLT) is a minimally invasive treatment for varicose veins. This study compares early quality-of-life (QoL) outcomes following EVLT and surgery. Two nonrandomized groups were studied: an EVLT group with 70 patients, median age 49 (interquartile range [IQR] 35-58) years, and a surgery group with 62 patients, median age 49 (IQR 35-61) years. Patients were assessed prior to and at 1, 6, and 12 weeks following the procedure using the Short Form 36 (SF-36), the Aberdeen Varicose Veins Questionnaire (AVVQ), and the Venous Clinical Severity Score (VCSS). Follow-up at 1, 6, and 12 weeks was 100%, 77%, and 70% following EVLT and 100%, 85%, and 47% following surgery. SF-36 scores were significantly better in the EVLT group at 1 week (Physical Functioning, Role Physical, Bodily Pain, Vitality, and Social Functioning domains) and at 6 weeks (Physical Functioning and Role Physical). At 12 weeks, no significant differences were evident between the groups. AVVQ scores were significantly better in the EVLT group at 6 and 12 weeks. VCSS scores were significantly improved in both groups at 12 weeks. EVLT and surgery provide similar QoL improvements in patients with varicose veins. EVLT, however, removes the QoL limitations experienced by patients in the early postoperative period.

Pretreatment with hyperbaric oxygen and its effect on neuropsychometric dysfunction and systemic inflammatory response after cardiopulmonary bypass: a prospective randomized double-blind trial.

OBJECTIVE: Animal studies have shown that pretreatment with hyperbaric oxygen can induce central nervous system ischemic tolerance and also modulate the inflammatory response. We evaluated this therapy in patients undergoing cardiopulmonary bypass. METHODS: Sixty-four patients were prospectively randomized to group A (n = 31; atmospheric air, 1.5 atmospheres absolute) or group B (n = 33; hyperbaric oxygen, 2.4 atmospheres absolute) before on-pump coronary artery bypass grafting. Age, sex, body mass index, diabetes, hypertension, smoking, coronary disease severity, left ventricular function, Parsonnet score, Euroscore, bypass time, myocardial ischemia time, and number of grafts were comparable in both groups. Canadian Cardiovascular Society angina, New York Heart Association dyspnea, and previous myocardial infarction were significantly higher in group B. Inflammatory markers were analyzed before surgery and 2 and 24 hours after bypass. Neuropsychometric testing was performed 48 hours before surgery and 4 months after surgery and included trail making A and B, the Rey auditory verbal learning test, grooved peg board, information processing table A, and digit span forward and backward. Neuropsychometric dysfunction was defined as more than 1 SD deterioration in more than 2 neuropsychometric tests. Chi-square tests, Fisher tests, t tests, and analysis of variance were used as appropriate for statistical analysis. RESULTS: Group A had a significant postoperative increase in the inflammatory markers soluble E-selectin, CD18, and heat shock protein 70. This was not observed in group B. Neuropsychometric dysfunction was also significantly higher in group A compared with group B. There was no difference in any other early postoperative clinical outcome. CONCLUSIONS: Our results seem to indicate that pretreatment with hyperbaric oxygen can reduce neuropsychometric dysfunction and also modulate the inflammatory response after cardiopulmonary bypass. However, further multicenter randomized trials are needed to clinically evaluate this form of therapy.